CN117766984A - Antenna assembly and electronic equipment - Google Patents

Abstract

The embodiment of the application provides an antenna assembly, which comprises a radiation branch, a feed source, a first lumped element and a second lumped element. The radiating branch comprises a first end, a second end and a feeding point, wherein the first end is an open-circuit end. The feed source is connected with the feed point and is used for exciting the radiation branches to work in a preset frequency band. The first lumped element is connected between the second end and the ground and is used for forming a first high-frequency radiation zero point at a first high-frequency which is higher than the highest frequency of the preset frequency band and is smaller than or equal to the preset frequency interval. The second lumped element is connected between the second end and the ground and is used for forming a first low-frequency radiation zero point at a first low-frequency, wherein the first low-frequency is lower than the lowest frequency of the preset frequency band and the frequency interval between the first low-frequency and the lowest frequency of the preset frequency band is smaller than or equal to the preset frequency interval. The application also provides electronic equipment. The method and the device can effectively ensure the radiation performance of the preset frequency band.

Description

Antenna assembly and electronic equipment

Technical Field

The present disclosure relates to the field of communications technologies, and in particular, to an antenna assembly and an electronic device having the antenna assembly.

Background

At present, with the popularization of 5G communication technology, the communication experience of people is better, the antennas are more and more, and the antenna frequency bands required to be supported are more and more. In some cases, in order to ensure interference between antennas, a filter is often required to be added to perform filtering processing to suppress nearby frequency bands outside the supported frequency band, so as to ensure radiation performance of the antennas operating in the preset frequency band. However, in the prior art, a special filter is required to be additionally added, resulting in an increase in size and cost.

Disclosure of Invention

The application provides an antenna assembly and electronic equipment, so as to solve the problem.

In a first aspect, an antenna assembly is provided that includes a radiating stub, a feed, a first lumped element, and a second lumped element. The radiating branch comprises a first end, a second end and a feeding point, wherein the first end is an open-circuit end. The feed source is connected with the feed point and is used for exciting the radiation branch to work in a preset frequency band. The first lumped element is connected between the second end and the ground and is used for forming a first high-frequency radiation zero point at a first high-frequency, wherein the first high-frequency is higher than the highest frequency of the preset frequency band, and the frequency interval between the first high-frequency and the highest frequency of the preset frequency band is smaller than or equal to the preset frequency interval. The second lumped element is connected between the second end and the ground and is used for forming a first low-frequency radiation zero point at a first low-frequency, wherein the first low-frequency is lower than the lowest frequency of the preset frequency band, and the frequency interval between the first low-frequency and the lowest frequency of the preset frequency band is smaller than or equal to the preset frequency interval.

In a second aspect, there is also provided an electronic device comprising an antenna assembly. The antenna assembly includes a radiating stub, a feed, a first lumped element, and a second lumped element. The radiating branch comprises a first end, a second end and a feeding point, wherein the first end is an open-circuit end. The feed source is connected with the feed point and is used for exciting the radiation branch to work in a preset frequency band. The first lumped element is connected between the second end and the ground and is used for forming a first high-frequency radiation zero point at a first high-frequency, wherein the first high-frequency is higher than the highest frequency of the preset frequency band, and the frequency interval between the first high-frequency and the highest frequency of the preset frequency band is smaller than or equal to the preset frequency interval. The second lumped element is connected between the second end and the ground and is used for forming a first low-frequency radiation zero point at a first low-frequency, wherein the first low-frequency is lower than the lowest frequency of the preset frequency band, and the frequency interval between the first low-frequency and the lowest frequency of the preset frequency band is smaller than or equal to the preset frequency interval.

According to the electronic equipment and the antenna assembly, one end of the radiation branch is grounded through the first lumped element and the second lumped element, and the first high-frequency radiation zero point and the first low-frequency radiation zero point are formed on two sides of the preset frequency band respectively through the first lumped element and the second lumped element, and the frequency interval between the frequency corresponding to the first high-frequency radiation zero point and the highest frequency of the preset frequency band and the frequency interval between the frequency corresponding to the first low-frequency radiation zero point and the lowest frequency of the preset frequency band are smaller than or equal to the preset frequency interval, so that the radiation efficiency of a nearby frequency band of the preset frequency band can be reduced, the suppression of the nearby frequency band of the preset frequency band can be effectively realized, the radiation performance of the preset frequency band can be ensured, and the cost and the space are effectively saved because an independent filter is not required to be additionally increased.

Drawings

In order to more clearly describe the technical solutions in the embodiments or the background of the present application, the following description will describe the drawings that are required to be used in the embodiments or the background of the present application.

Fig. 1 is a schematic diagram of a simple structure of an antenna assembly according to an embodiment of the present application.

Fig. 2 is a further schematic structural diagram of an antenna assembly in some embodiments of the present application.

Fig. 3 is a schematic diagram illustrating radiation efficiency curves of an antenna assembly according to some embodiments of the present application.

Fig. 4 is a schematic diagram of impedance curves of an antenna assembly according to some embodiments of the present application.

Fig. 5 is a further schematic structural diagram of an antenna assembly in some embodiments of the present application.

Fig. 6 is a schematic diagram of magnetic field coupling between a radiating branch and the first parasitic branch of an antenna assembly to create a phase difference at a second high frequency in some embodiments of the present application.

Fig. 7 is a schematic diagram of magnetic field coupling between a radiating branch and the second parasitic branch of an antenna assembly to create a phase difference at a second low frequency in some embodiments of the present application.

Fig. 8 is a more specific structural schematic diagram of an antenna assembly in some embodiments of the present application.

Fig. 9 is a more specific further structural schematic diagram of an antenna assembly in some embodiments of the present application.

Fig. 10 is a more specific further structural schematic diagram of an antenna assembly in some embodiments of the present application.

Fig. 11 is a schematic diagram of return loss curves of an antenna assembly in some embodiments of the present application.

Fig. 12 is another radiation efficiency curve of an antenna assembly in some embodiments of the present application.

Fig. 13 is a normalized radiation pattern of an antenna assembly in some embodiments of the present application.

Fig. 14 is another normalized radiation pattern of an antenna assembly in some embodiments of the present application.

Fig. 15 is a block diagram of an electronic device in some embodiments of the present application.

Fig. 16 is a schematic view showing a part of the internal structure of the electronic apparatus.

Fig. 17 is a schematic plan view of an electronic device in some embodiments of the present application.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without any inventive effort, are intended to be within the scope of the invention.

In the description of the embodiments of the present invention, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "thickness", "width", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not imply or indicate that the apparatus or element to be referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. The term "coupled" as used herein includes direct coupling, indirect coupling, and electrical coupling. In the description of the embodiments of the present invention, the terms "first", "second", and the like are not particularly limited, but rather, in order to distinguish between the same-named objects, the terms "first", "second", and the like refer to the same-named objects in the case of the description. Herein, "a" and/or "B" in the present application include "a" or "B", and "a" and "B", etc.

Referring to fig. 1, a simplified structure of an antenna assembly 1 according to an embodiment of the present application is shown. As shown in fig. 1, the antenna assembly 1 comprises a radiating stub 11, a feed 12, a first lumped element 13 and a second lumped element 14. The radiating branch 11 includes a first end 11a, a second end 11b, and a feeding point F1, where the first end 11a is an open end. The feed source 12 is connected with the feed point F1 and is used for exciting the radiation branch 11 to work in a preset frequency band. The first lumped element 13 is connected between the second end 11b and ground, and the first lumped element 13 is configured to form a first high-frequency radiation zero point at a first high-frequency, where the first high-frequency is higher than a highest frequency of the preset frequency band and a frequency interval between the first high-frequency and the highest frequency of the preset frequency band is smaller than or equal to a preset frequency interval. The second lumped element 14 is connected between the second end 11b and ground for forming a first low frequency radiation zero at a first low frequency, wherein the first low frequency is lower than the lowest frequency of the preset frequency band and the frequency interval between the first low frequency and the lowest frequency of the preset frequency band is smaller than or equal to the preset frequency interval.

Therefore, in the present application, the first high-frequency radiation zero and the first low-frequency radiation zero are formed on two sides of the preset frequency band by the first lumped element 13 and the second lumped element 14, and the frequency interval between the frequency corresponding to the first high-frequency radiation zero and the highest frequency of the preset frequency band and the frequency interval between the frequency corresponding to the first low-frequency radiation zero and the lowest frequency of the preset frequency band are smaller than or equal to the preset frequency interval, so that the radiation efficiency of the nearby frequency band of the preset frequency band can be reduced, the suppression of the nearby frequency band of the preset frequency band can be effectively realized, the radiation performance of the preset frequency band can be ensured, and the cost and the space are effectively saved because no additional independent filter is not needed.

The formation of the radiation zero at a certain frequency means that the radiation efficiency at the certain frequency is very low and is similar to zero radiation efficiency, wherein the radiation zero is also a trough point of the radiation efficiency, and when the radiation zero is at a certain frequency, the radiation efficiency in a certain surrounding frequency range is pulled down to a lower value, so that the radiation efficiency in a certain surrounding frequency range is a frequency band which cannot be supported by the antenna assembly 1 due to the low radiation efficiency. Therefore, when the frequency interval between the frequency corresponding to the first high-frequency radiation zero point and the highest frequency of the preset frequency band and the frequency interval between the frequency corresponding to the first low-frequency radiation zero point and the lowest frequency of the preset frequency band are smaller than or equal to the preset frequency interval, the frequency band in a certain frequency range around the first high-frequency radiation zero point is close to the highest frequency of the preset frequency band and forms a stop band at the high frequency of the preset frequency band, and the frequency band in a certain frequency range around the first low-frequency radiation zero point is close to the lowest frequency of the preset frequency band and forms a stop band at the low frequency of the preset frequency band. Therefore, the radiation efficiency of the frequency bands at both sides of the preset frequency band is suppressed, and since the antenna assembly 1 supports the preset frequency band and the electromagnetic wave signals of the frequency bands at both sides of the preset frequency band are interference signals, the radiation efficiency of the frequency bands at both sides of the preset frequency band is suppressed, that is, the interference signals are filtered out, so that the radiation performance of the preset frequency band can be ensured or improved.

The first high-frequency and the first low-frequency in the present application refer to the high-frequency and the low-frequency relative to the preset frequency band, and not refer to frequencies in a frequency band such as a high-frequency band or a low-frequency band in a 4G or 5G communication network. That is, as described above, the first high frequency is a frequency higher than the highest frequency of the preset frequency band and having a frequency interval with the highest frequency of the preset frequency band less than or equal to a preset frequency interval, and the first low frequency is a frequency lower than the lowest frequency of the preset frequency band and having a frequency interval with the lowest frequency of the preset frequency band less than or equal to a preset frequency interval.

Referring to fig. 2, a schematic diagram of an antenna assembly 1 according to some embodiments of the present application is shown. As shown in fig. 2, the first lumped element 13 and the second lumped element 14 each include at least one capacitor C1 and at least one inductor L1, the first lumped element 13 is configured to cause the radiation branch 11 to be impedance mismatched at the first high frequency to form a first high frequency radiation zero, and the second lumped element 14 is configured to cause the radiation branch 11 to be impedance mismatched at the first low frequency to form a first low frequency radiation zero.

That is, in some embodiments, the first lumped element 13 and the second lumped element 14 may be lumped elements composed of a combination of a capacitor and an inductor including at least one capacitor C1 and at least one inductor L1. And the first lumped element 13 is for impedance mismatch of the radiating branch 11 at the first high frequency to form a first high frequency radiation zero, and the second lumped element 14 is for impedance mismatch of the radiating branch 11 at the first low frequency to form a first low frequency radiation zero.

Wherein, in this application, an impedance mismatch at a certain frequency refers to an impedance mismatch at that frequency.

In some embodiments, when the antenna assembly 1 is impedance matched at a certain frequency or frequency band, the radiation efficiency at the frequency or frequency band is optimal, and when the impedance of the antenna assembly 1 is not matched at the certain frequency or frequency band, that is, the impedance is mismatched, the radiation efficiency at the frequency or frequency band is low, so that the transmission and reception of electromagnetic wave signals of the frequency or frequency band cannot be supported. Further, an impedance mismatch in the present application may refer to a complete mismatch in impedance, resulting in substantially zero radiation efficiency at that frequency, while exhibiting a radiation null.

Therefore, in this application, by adding the first lumped element 13 and the second lumped element 14, where the first lumped element 13 and the second lumped element 14 each include at least one capacitor C1 and at least one inductor L1, the at least one capacitor C1 and the at least one inductor L1 included in the first lumped element 13 as a whole have corresponding impedance values, so that the matching impedance of the antenna assembly 1 is changed, and the radiating branch 11 is impedance mismatched at the first high frequency. Similarly, the second lumped element 14 includes at least one capacitor C1 and at least one inductor L1, which together have a certain impedance value, which causes a change in the matching impedance of the antenna assembly 1, and causes an impedance mismatch of the radiating branch 11 at the first low frequency.

The number of the capacitors C1 and the inductors L1 included in the first lumped element 13, and specific capacitance values and inductance values may be a structure and a value obtained by previously performing impedance mismatch of the radiating branch 11 at the first high frequency according to a simulation test. Likewise, the number of capacitances C1 and inductances L1 and specific capacitance and inductance values included in the second lumped element 14 may be a structure and a value obtained by previously impedance-mismatched the radiating branch 11 at the first low frequency according to a simulation test.

In some embodiments, as shown in fig. 2, the first lumped element 13 includes a first capacitor C11 and a first inductor L11 connected in series between the second terminal 11b and ground, and the second lumped element 14 includes a second capacitor C12 and a second inductor L12 connected in series between the second terminal and ground.

That is, in some embodiments, the first lumped element 13 may include a first capacitor C11 and a first inductor L11 connected in series between the second terminal 11b and ground, and the second lumped element 14 may include a second capacitor C12 and a second inductor L12 connected in series between the second terminal 11b and ground. As mentioned above, the capacitance value of the first capacitor C11 and the inductance value of the first inductor L11 included in the first lumped element 13 may be values obtained by impedance mismatch of the radiating branch 11 at the first high frequency according to a simulation test in advance. Similarly, the capacitance value of the second capacitor C12 and the inductance value of the second inductor L12 included in the second lumped element 14 may be values obtained by previously matching the impedance of the radiating branch 11 at the first low frequency according to a simulation test.

In some embodiments, the first lumped element 13 includes a first capacitor C11 and a first inductor L11 connected in series between the second end 11b and ground, and the second lumped element 14 may specifically include a second capacitor C12 and a second inductor L12 connected in series between the second end 11b and ground, where a product of a capacitance value of the first capacitor C11 and an inductance value of the first inductor L11 is smaller than a product of a capacitance value of the second capacitor C12 and an inductance value of the second inductor L12. That is, assuming that the capacitance value of the first capacitor C11 is C11, the inductance value of the first inductor L11 is L11, the capacitance value of the second capacitor C12 is C12, and the inductance value of the second inductor L12 is L12, L11×c11 is smaller than L12×c12.

When the lumped element comprises a capacitor and an inductor which are connected in series, and a radiation zero point is formed at a certain frequency, a frequency f0 at the radiation zero point is formed, that is, the frequency f0 corresponding to the radiation zero point satisfies the relation:

wherein L is an inductance value of an inductance included in the lumped element, and C is a capacitance value of a capacitance included in the lumped element.

Therefore, in this application, when the product of the capacitance value of the first capacitor C11 and the inductance value of the first inductor L11 of the first lumped element 13 is smaller than the product of the capacitance value of the second capacitor C12 and the inductance value of the second inductor L12 of the second lumped element 14, the frequency corresponding to the radiation zero point formed by the first lumped element 13 will be higher than the frequency corresponding to the radiation zero point formed by the second lumped element 14. Thus, the first lumped element 13 may form a first high frequency radiation zero at a first high frequency and the second lumped element 14 may form a first low frequency radiation zero at a first low frequency.

In some embodiments, the capacitance value of the first capacitor C11 may be 0.8pF (picofarad), and the inductance value of the first inductor L11 may be 3.3nH (nanohenry); the capacitance value of the second capacitor C12 is 1.1pF, and the inductance value of the second inductor L12 is 3.3nH. It is to be understood that these specific values are merely exemplary and that other suitable values are possible as previously described.

In fig. 2, only the first lumped element 13 includes a first capacitor C11 and a first inductor L11 connected in series between the second terminal 11b and ground, and the second lumped element 14 includes a second capacitor C12 and a second inductor L12 connected in series between the second terminal and ground. In some embodiments, the first lumped element 13 and the second lumped element 14 may also comprise other structures. For example, the first lumped element 13 may include a first capacitor C11 and a first inductor L11 connected in parallel between the second terminal 11b and the ground, or may further include a parallel structure or a series structure of a plurality of capacitors and a plurality of inductors, and the second lumped element 14 may also include a second capacitor C12 and a second inductor L12 connected in parallel between the second terminal and the ground, or may also include a parallel structure or a series structure of a plurality of capacitors and a plurality of inductors. It is only necessary that the first lumped element 13 is satisfied such that the radiating branches 11 are impedance mismatched at the first high frequency and the second lumped element 14 is such that the radiating branches 11 are impedance mismatched at the first low frequency.

In this application, the first lumped element 13 is connected between the second end 11b and the ground, including that the first lumped element 13 is connected between the end of the second end 11b and the ground, and also includes that the first lumped element 13 is connected between the position of the radiating branch 11 near the second end 11b and the ground, and likewise, the second lumped element 14 is connected between the second end 11b and the ground, including that the second lumped element 14 is connected between the end of the second end 11b and the ground, and also includes that the second lumped element 14 is connected between the position of the radiating branch 11 near the second end 11b and the ground.

That is, in the present application, the first lumped element 13 and the second lumped element 14 are connected to the second end 11b of the radiating stub 11, not to be connected to the second end 11b in a strict sense, but may include connection to a position of the radiating stub 11 near the second end 11b, for example, a distance between a position of the first lumped element 13 and the second lumped element 14 connected to the radiating stub 11 and the second end 11b is less than a predetermined distance, for example, 1 cm, and it is considered that the first lumped element 13 and the second lumped element 14 are connected to the second end 11b of the radiating stub 11.

Wherein in some embodiments the locations where the first lumped element 13 and the second lumped element 14 are connected to the radiating stub 11 may be the same or different.

Wherein, as shown in fig. 1 and 2, the first end 11a of the radiating stub 11 is an open end, and the second end 11b of the radiating stub 11 or a position near the second end 11b is grounded through the first lumped element 13 and the second lumped element 14, and the feeding point F1 is located between the connection position of the first lumped element 13 and the second lumped element 14 and the first end 11a, the radiating stub 11 substantially forms an inverted-F antenna (IFA, inverted F antenna).

Wherein, in some embodiments, the preset frequency interval is 350MHz.

That is, in some embodiments, the first lumped element 13 forms a first high frequency radiation zero at a first high frequency that is higher than and spaced less than or equal to 350MHz from the highest frequency of the preset frequency band. The second lumped element 14 forms a first low frequency radiation zero at a first low frequency that is lower than and spaced from the lowest frequency of the predetermined frequency band by less than or equal to 350MHz.

When a certain frequency is the radiation zero point, the radiation efficiency in a certain surrounding frequency range is reduced to a lower value, for example, lower than a preset radiation efficiency value, so that the certain surrounding frequency range is a frequency band which cannot be supported by the antenna component 1 due to low radiation efficiency, therefore, when a first high frequency corresponding to the first high frequency radiation zero point is higher than the highest frequency of the preset frequency band and the frequency interval between the first high frequency zero point and the highest frequency of the preset frequency band is smaller than or equal to 350MHz, the radiation efficiency in the certain surrounding frequency range of the first high frequency is reduced to be lower than the preset radiation efficiency value, and the certain surrounding frequency range which takes the first high frequency as the center frequency is reduced to be lower than the preset radiation efficiency value, for example, 200MHz, 400MHz and the like, therefore, when the frequency interval between the lowest frequency of the certain surrounding frequency range of the first high frequency and the highest frequency band is higher than the highest frequency of the preset frequency band, the radiation efficiency in the vicinity of the preset frequency band can not be restrained, and the radiation efficiency can not be effectively restrained at the highest frequency of the left or right of the frequency band, and the adjacent frequency ranges can not be restrained at the highest frequency of the preset frequency band, and the highest frequency can be restrained at the highest frequency of the left frequency.

Similarly, when the first low-frequency radiation zero point corresponds to a first low-frequency higher than the lowest frequency of the preset frequency band and the frequency interval between the first low-frequency radiation zero point and the lowest frequency of the preset frequency band is smaller than or equal to 350MHz, the radiation efficiency in a certain frequency range around the first low-frequency is lowered to a lower value, for example, the radiation efficiency value is also lower than the preset radiation efficiency value, and the certain frequency range around the first low-frequency radiation zero point which is lowered to the lower value generally has hundreds of MHz, for example, 400MHz, etc., so that the interval between the highest frequency of the certain frequency range around the first low-frequency radiation zero point and the lowest frequency of the preset frequency band is only about 100MHz, and therefore, a frequency band which is lower in radiation efficiency and cannot work starts to appear at a frequency about 100MHz lower than the lowest frequency of the preset frequency band, and therefore, adjacent frequency bands around the lowest frequency of the preset frequency band can be effectively restrained. Therefore, adjacent frequency bands on the high side and the low side of the preset frequency band can be effectively restrained, and radiation performance in the preset frequency band is ensured or improved.

The preset radiation efficiency value can be a critical value for representing whether the radiation efficiency meets the electromagnetic wave receiving and transmitting condition, and when the radiation efficiency of a certain frequency band is higher than or equal to the preset radiation efficiency value, the radiation efficiency meets the electromagnetic wave receiving and transmitting condition, and the device can work in the frequency band with the radiation efficiency higher than or equal to the preset radiation efficiency value to a certain extent; when the radiation efficiency of a certain frequency band is lower than the preset radiation efficiency value, the radiation efficiency cannot meet the electromagnetic wave receiving and transmitting condition, and cannot work in the frequency band with the radiation efficiency lower than the preset radiation efficiency value.

In some embodiments, the preset radiant efficiency value may be-17 dB. It is clear that in some embodiments, the preset radiation efficiency value may also be other suitable values, for example, -15dB, -14dB values.

Wherein a predetermined frequency band is a desired operating frequency band of the antenna assembly 1, it is optimal that the radiation efficiency in a frequency range from the highest frequency of the predetermined frequency band to a higher frequency is reduced to a lower value, e.g. lower than the predetermined radiation efficiency value, and the radiation efficiency in a frequency range from the lowest frequency of the predetermined frequency band to a lower frequency is reduced to a lower value, e.g. lower than the predetermined radiation efficiency value. However, since the radiation efficiency generally cannot be suddenly changed, a certain buffer frequency interval is required, and generally, the buffer frequency interval is about 100MHz, so that the frequency selectivity is better, that is, the operation frequency band is selected, and the effect of suppressing the adjacent frequency bands of the operation frequency band is better. Therefore, in general, when the radiation efficiency in a frequency range from about 100MHz higher than the highest frequency of the preset frequency band is reduced to a lower value, and the radiation efficiency in a frequency range from about 100MHz lower than the lowest frequency of the preset frequency band is reduced to a lower value, effective suppression of adjacent frequency bands on both sides of the preset frequency band can be better achieved, and the radiation performance in the preset frequency band is ensured or improved.

Therefore, in the present application, when the first high-frequency corresponding to the first high-frequency radiation zero point is higher than the highest frequency of the preset frequency band and the frequency interval between the first high-frequency radiation zero point and the highest frequency of the preset frequency band is less than or equal to 350MHz, and the first low-frequency corresponding to the first low-frequency radiation zero point is higher than the lowest frequency of the preset frequency band and the frequency interval between the first low-frequency radiation zero point and the lowest frequency of the preset frequency band is less than or equal to 350MHz, the radiation efficiency of a certain frequency range around the first high-frequency can be reduced to a lower value approximately, and the interval between the lowest frequency around the first high-frequency range and the highest frequency of the preset frequency band is only about 100MHz, and the radiation efficiency of a certain frequency range around the first low-frequency range is reduced to a lower value approximately, and the interval between the highest frequency around the first low-frequency range and the lowest frequency of the preset frequency range is only about 100 MHz. Therefore, adjacent frequency bands near the lowest frequency of the preset frequency band can be effectively restrained.

In some embodiments, the preset frequency interval may also be other values, for example, 400MHz, 370MHz, 300MHz, etc., as long as the lowest frequency of a certain frequency range around the first high frequency is approximately close to the highest frequency of the preset frequency band and the highest frequency of a certain frequency range around the first low frequency is approximately close to the lowest frequency of the preset frequency band. For example, it is sufficient that the interval between the lowest frequency of the certain frequency range around the first high frequency and the highest frequency of the preset frequency band is close to 100MHz, for example 150MHz, and the interval between the highest frequency of the certain frequency range around the first low frequency and the lowest frequency of the preset frequency band is close to 100MHz, for example 150 MHz.

Fig. 3 is a schematic diagram illustrating radiation efficiency curves of the antenna assembly 1 according to some embodiments of the present application. Fig. 3 may be a schematic diagram of a radiation efficiency curve obtained by performing a simulation test on the antenna assembly 1 shown in fig. 1 or fig. 2 operating in a preset frequency band.

Wherein fig. 3 schematically shows a radiation efficiency curve Sr1, as mentioned above, forming a radiation zero at a certain frequency means that the radiation efficiency at said frequency is very low, approximately zero radiation efficiency, wherein the radiation zero is also the trough point of the radiation efficiency, i.e. the trough point of the radiation efficiency curve. As shown in fig. 3, the antenna assembly 1 in the present application, through the first lumped element 13 and the second lumped element 14, two radiation efficiency dips, i.e. two radiation zero points, i.e. the aforementioned first high frequency radiation zero point H10 and first low frequency radiation zero point L10, appear.

In some embodiments, the frequency range of the preset frequency band may be 2.2 GHz-2.5 GHz, that is, greater than or equal to 2.2GHz and less than or equal to 2.5GHz. As can be seen from the radiation efficiency curve Sr1 of fig. 3, the frequency corresponding to the first high-frequency radiation zero H10, that is, the first high-frequency is approximately 2.55GHz, and the frequency interval between the first high-frequency radiation zero H10 and the highest frequency 2.5GHz of the preset frequency band is smaller than the preset frequency interval, and the frequency interval between the first low-frequency radiation zero L10, that is, the first low-frequency is approximately 1.86GHz, and the lowest frequency 2.2GHz of the preset frequency band is smaller than the preset frequency interval.

As mentioned above, when a certain frequency is the radiation zero point, the radiation efficiency in a certain frequency range around the surrounding is pulled down to a lower value. As shown in fig. 3, the radiation efficiency of the first high-frequency radiation null H10 and the radiation efficiency of the first low-frequency radiation null L10 are both approximately-25 dB, which is already substantially equal to the radiation null with zero radiation efficiency. As shown in fig. 3, the radiation efficiency in the frequency range close to 100MHz centered around the frequency 2.55GHz corresponding to the first high-frequency radiation zero H10 is lower than the preset radiation efficiency value, for example, -17dB; and the radiation efficiency in the frequency range which is approximately 200MHz and takes the frequency 1.86GHz corresponding to the first low-frequency radiation zero L10 as the center is lower than the preset radiation efficiency value. Therefore, the adjacent frequency bands on the high side and the low side of the preset frequency band can be effectively restrained, and the radiation performance in the preset frequency band is ensured or improved.

Fig. 4 is a schematic diagram of impedance curves of the antenna assembly 1 according to some embodiments of the present application. Wherein fig. 4 may be a real and imaginary value of the impedance of the antenna assembly 1 at different frequencies, as exemplified by the antenna assembly 1 in fig. 1 or fig. 2.

The real part curve Z1 and the imaginary part curve Z2 of the impedance are specifically shown in fig. 4, where the impedance generally includes a resistor and a reactance, the resistor is the real part of the impedance, and the reactance is the imaginary part of the impedance. In fig. 4, the real impedance curve Z1 is a curve with black square points, and the imaginary impedance curve Z2 is a curve with white dots.

As can be seen from fig. 4, the real part of the impedance of the antenna assembly 1 is near zero in a certain frequency range including the frequency 2.55GHz corresponding to the first high-frequency radiation zero H10, i.e. including the first high-frequency, for example, from the frequency range approximately from 2.55GHz to 2.7GHz shown in fig. 4, the real part of the impedance of the antenna assembly 1 is near zero. Likewise, in a certain frequency range including the frequency 1.86GHz corresponding to the first low-frequency radiation zero point L10, that is, including the first low-frequency, the real part of the impedance of the antenna assembly 1 is also near zero, for example, from a frequency range of approximately 1.7GHz to 2.0GHz as shown in fig. 4, the real part of the impedance of the antenna assembly 1 is near zero.

Since the antenna assembly 1 of the present application mainly radiates the radiation branch 11, the impedance of the antenna assembly 1 mainly refers to the impedance of the radiation branch 11.

In general, when the real part of the impedance of the antenna assembly 1 is close to zero, the impedance mismatch is illustrated, and the reflection coefficient at this time is high, which seriously affects the radiation efficiency. Therefore, in this application, the foregoing use of the first lumped element 13 to cause the radiation branch 11 to be impedance mismatched at the first high frequency to form a first high frequency radiation zero may specifically refer to the use of the first lumped element 13 to cause the real part of the impedance of the radiation branch 11 at the first high frequency to be zero, while forming the first high frequency radiation zero at the first high frequency. The foregoing second lumped element 14 is used to make the impedance of the radiation branch 11 mismatched at the first low frequency to form a first low frequency radiation zero, which may also specifically refer to making the real part of the impedance of the radiation branch 11 at the first low frequency zero by the second lumped element 14, and forming the first low frequency radiation zero at the first low frequency.

Wherein, as shown in fig. 4, the first lumped element 13 makes the real part of the impedance of the radiation branch 11 at the first high frequency zero, and also makes the real part of the impedance in a certain frequency range including the first high frequency near zero, so that the radiation efficiency in a certain frequency range including the first high frequency is lower, for example, lower than the preset radiation efficiency value. Likewise, the second lumped element 14 makes the real part of the impedance of the radiating stub 11 at the first low frequency zero, and also makes the real part of the impedance in a certain frequency range including the first low frequency near zero, so that the radiation efficiency in a certain frequency range including the first low frequency is low, for example, lower than the preset radiation efficiency value.

In another aspect, the real impedance part of the radiating branch 11 is zero or near zero, and thus the current of the antenna component 1 is concentrated on the corresponding lumped element, so that the radiating branch 11 does not radiate and does not support the transmission and reception of electromagnetic wave signals of the frequencies.

Here, fig. 3 and fig. 4 are only for explaining the principle that the first lumped element 13 and the second lumped element 14 implement the radiation zero to perform the frequency band suppression, the preset frequency band may also be other frequency ranges, and specific values of the first high-frequency, the first low-frequency, and the like may be designed to other values as needed.

In some embodiments, the radiating stub 11 has an equivalent electrical length λ ₁ 4, wherein the lambda ₁ And the wavelength corresponding to the preset frequency band is obtained. Therefore, the radiation branch 11 can support the receiving and transmitting of the electromagnetic wave signals of the preset frequency band under the excitation of the feed source 12. The wavelength corresponding to the preset frequency band may specifically be a wavelength corresponding to a center frequency or a resonant frequency of the preset frequency band.

Referring to fig. 5, a further schematic structure of the antenna assembly 1 according to some embodiments of the present application is shown.

As shown in fig. 5, the antenna assembly 1 further includes a first parasitic branch 15 and a second parasitic branch 16, where the first parasitic branch 15 is coupled with the radiating branch 11 and is magnetic field coupled, and the first parasitic branch 15 is configured to form a second high-frequency radiation zero point at a second high-frequency, where the second high-frequency is higher than a highest frequency of the preset frequency band and a frequency interval between the second high-frequency radiation zero point and the highest frequency of the preset frequency band is smaller than or equal to the preset frequency interval. The second parasitic branch 16 is coupled to the radiation branch 11 and is an electric field coupling, and the second parasitic branch 16 is configured to form a second low-frequency radiation zero at a second low-frequency, where the second low-frequency is lower than a lowest frequency of the preset frequency band and a frequency interval between the second low-frequency and the lowest frequency of the preset frequency band is less than or equal to the preset frequency interval.

That is, in some embodiments, the antenna assembly 1 forms a second high-frequency radiation zero at a second high-frequency through a first parasitic branch 15 in addition to the first high-frequency radiation zero at the first high-frequency through the first lumped element 13, and the second high-frequency is also higher than the highest frequency of the preset frequency band and a frequency interval from the highest frequency of the preset frequency band is smaller than or equal to the preset frequency interval; and forming a second low-frequency radiation zero at a second low-frequency through the second parasitic branch 16 in addition to forming a first low-frequency radiation zero at the first low-frequency through the second lumped element 14, and the second low-frequency is also lower than the lowest frequency of the preset frequency band and a frequency interval from the lowest frequency of the preset frequency band is less than or equal to the preset frequency interval. Therefore, in the present application, the first lumped element 13 and the first parasitic branch 15 may form a radiation zero at a frequency higher than the preset frequency band and close to the preset frequency band, and the second lumped element 14 and the second parasitic branch 16 may form a radiation zero at a frequency lower than the preset frequency band and close to the preset frequency band, so that adjacent frequency bands on two sides of the preset frequency band can be further accurately suppressed, and frequency selectivity of the preset frequency band is improved.

The second high-frequency and the second low-frequency in the present application also refer to the high-frequency and the low-frequency relative to the preset frequency band, and do not refer to frequencies in the frequency band such as the high-frequency band or the low-frequency band in the 4G or 5G communication network. That is, as described above, the second high frequency is a frequency higher than the highest frequency of the preset frequency band and having a frequency interval with the highest frequency of the preset frequency band less than or equal to a preset frequency interval, and the second low frequency is a frequency lower than the lowest frequency of the preset frequency band and having a frequency interval with the lowest frequency of the preset frequency band less than or equal to a preset frequency interval.

Wherein in some embodiments, the second high frequency may be the same as or different from the first high frequency, and the second low frequency may be the same as or different from the first low frequency. The radiation zero points generated by the lumped element and the parasitic branches have a certain difference in characteristics, for example, the bandwidth of the radiation zero point generated by the lumped element is wider, that is, the surrounding frequency range of the radiation efficiency is reduced to a lower value is larger, and the radiation zero point generated by the parasitic branches is steeper in the decreasing slope of the radiation efficiency. Thus, in some embodiments, even though the second high frequency is the same as the first high frequency, the second low frequency is the same as the first low frequency, it is helpful to suppress adjacent frequency bands on both sides of the preset frequency band.

In some embodiments, the second high frequency is different from the first high frequency, and the second low frequency is also different from the first low frequency. That is, by the first lumped element 13 and the first parasitic branch 15, radiation zeros are formed at two different frequencies higher than and close to the preset frequency band, while by the second lumped element 14 and the second parasitic branch 16, radiation zeros may be formed at two different frequencies lower than and close to the preset frequency band. When the second high-frequency is different from the first high-frequency, the second low-frequency is also different from the first low-frequency, two adjacent frequency bands on two sides of the preset frequency band can be well restrained, so that the frequency range with the radiation efficiency lower than the preset radiation efficiency value is wider, and the frequency interval between the frequency range with the radiation efficiency lower than the preset radiation efficiency value and the preset frequency band is small, thereby realizing good frequency band selectivity. In this application, the following description will mainly take an example that the second high-frequency is different from the first high-frequency, and the second low-frequency is also different from the first low-frequency.

When there are only two radiation zeros, i.e., the first high-frequency radiation zero and the first low-frequency radiation zero, the frequency range with the radiation efficiency lower than the preset radiation efficiency value may be narrower due to only one radiation zero, or the frequency interval between the frequency range with the radiation efficiency lower than the preset radiation efficiency value and the preset frequency band may be larger, so that the adjacent frequency band cannot be well suppressed.

For example, as shown in fig. 3, the frequency range of the preset frequency band may be 2.2 GHz-2.5 GHz, that is, 2.2GHz or more and 2.5GHz or less, when the first lumped element 13 forms the first high-frequency radiation zero point at the first high-frequency, the frequency corresponding to the first high-frequency radiation zero point H10, that is, the first high-frequency is approximately 2.55GHz, and the frequency interval between the first high-frequency radiation zero point H10 and the highest frequency 2.5GHz of the preset frequency band is small, so that effective suppression can be performed relatively quickly at the high frequency side of the preset frequency band, however, as shown in fig. 3, the radiation efficiency is lower than the frequency range of the preset radiation efficiency, for example, -17dB, and is smaller than 100MHz, so that the radiation efficiency may rise at the frequency not far from the highest frequency interval of the preset frequency band, and thus the wide suppression cannot be realized. As mentioned above, when a certain frequency is the radiation zero point, the radiation efficiency in a certain frequency range around the surrounding is pulled down to a lower value. As shown in fig. 3, when the second lumped element 14 forms the first low-frequency radiation zero point at the first low-frequency, the radiation efficiency in the frequency range of approximately 200MHz centered on the first low-frequency is lower than the preset radiation efficiency value by the frequency corresponding to the first low-frequency radiation zero point L10, that is, the first low-frequency is 1.86GHz, so that the suppression of a wider frequency band can be achieved, but the frequency interval between the first low-frequency and the lowest frequency 2.2GHz of the preset frequency band reaches 340MHz, the interval is larger, and a frequency interval with a wider radiation efficiency close to the preset frequency band exists on the low-frequency side of the preset frequency band, so that the suppression of a frequency cannot be achieved faster on the low-frequency side of the preset frequency band.

Therefore, in the present application, the first parasitic branch 15 forms a radiation zero at a second high-frequency position higher than the preset frequency band and close to the preset frequency band, and the second parasitic branch 16 forms a radiation zero at a second low-frequency position lower than the preset frequency band and close to the preset frequency band, so that adjacent frequency bands on two sides of the preset frequency band can be further accurately suppressed, the frequency selectivity of the preset frequency band is improved, and the radiation performance of the preset frequency band is improved.

Wherein, as shown in fig. 5, the first parasitic branch 15 includes a first ground terminal G1 and a first open-circuit terminal O1, the second parasitic branch 16 includes a second ground terminal G2 and a second open-circuit terminal O2, the first ground terminal G1 and the second ground terminal G2 are grounded, wherein the first ground terminal G1 of the first parasitic branch 15 is adjacent to the feed point F1 of the radiation branch 11 and the second open-circuit terminal O2 of the second parasitic branch 16 is adjacent to the first end 11a of the radiation branch 11, which is closer to the feed point F1 of the radiation branch 11 than the second ground terminal G2 of the second parasitic branch 16.

Wherein, when the radiation branch 11 resonates, the electric field is mainly concentrated at the open end of the radiation branch 11, that is, at the first end 11a, and the magnetic field is concentrated at the feeding position of the radiation branch 11, that is, near the feeding point F1, so when the first ground end G1 of the first parasitic branch 15 is adjacent to the feeding point F1 of the radiation branch 11 and is closer to the feeding point F1 of the radiation branch 11 than the second ground end G2, the first parasitic branch 15 will be magnetically coupled with the radiation branch 11, and when the second open end O2 of the second parasitic branch 16 is adjacent to the first end 11a of the radiation branch 11, the second parasitic branch 16 will be electrically coupled with the radiation branch 11.

Wherein the proximity of the second open end O2 of the second parasitic branch 16 to the first end 11a of the radiating branch 11 may mean that a distance between the second open end O2 of the second parasitic branch 16 and the first end 11a of the radiating branch 11 is less than a preset distance, for example less than 1 cm.

In some embodiments, the equivalent electrical length of the radiating branch 11 meets the resonance requirement of a preset frequency band, the resonance frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the preset frequency band and the second high-frequency band, and the resonance frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low-frequency band.

Wherein, the fact that the equivalent electrical length of the radiation branch 11 meets the resonance requirement of the preset frequency band may mean that the equivalent electrical length of the radiation branch 11 is λ ₁ 4, wherein the lambda ₁ And the wavelength corresponding to the preset frequency band is obtained. The resonant frequency corresponding to the equivalent electrical length of the first parasitic branch 15 refers to 1/4 of the wavelength corresponding to the resonant frequency of the equivalent electrical length of the first parasitic branch 15, and the resonant frequency corresponding to the equivalent electrical length of the second parasitic branch 16 refers to 1/4 of the wavelength corresponding to the resonant frequency of the equivalent electrical length of the second parasitic branch 16.

The resonant frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the preset frequency band and the second high-frequency, specifically, the resonant frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the highest frequency of the preset frequency band and the second high-frequency, the resonant frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low-frequency, and specifically, the resonant frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the lowest frequency of the preset frequency band and the second low-frequency.

In some embodiments, the first parasitic branch 15 has an equivalent electrical length λ ₂ 4, wherein the lambda ₂ For the wavelength corresponding to the frequency between the preset frequency band and the second high-frequency, the equivalent electrical length of the second parasitic branch 16 is λ ₃ 4, wherein the lambda ₃ And the wavelength is the wavelength corresponding to the frequency between the preset frequency band and the second low-frequency.

The equivalent electrical length of the radiating branch 11 meets the resonance requirement of a preset frequency band, the resonance frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the preset frequency band and the second high-frequency, the resonance frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low-frequency, and when the first parasitic branch 15 and the radiating branch 11 are magnetically coupled, the currents at the second high-frequency in the radiating branch 11 and the first parasitic branch 15 are inverted, so that a second high-frequency radiation zero is formed; when the second parasitic branch 16 is coupled to the radiating branch 11 by an electric field, the currents at the second low frequency in the radiating branch 11 and the second parasitic branch 16 will be inverted, forming a second low frequency radiation zero.

In some embodiments, the resonant frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the preset frequency band and the second high-frequency, and the first parasitic branch 15 may be designed according to the frequency at which the second high-frequency radiation zero point is expected to occur, that is, the second high-frequency, so that the equivalent electrical length of the first parasitic branch 15 is 1/4 of the wavelength corresponding to a certain frequency located between the highest frequency of the preset frequency band and the second high-frequency. Likewise, the resonant frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low-frequency, and the second parasitic branch 16 may be designed in advance according to the frequency at which the second low-frequency radiation zero point is expected to occur, that is, the second low-frequency, so that the equivalent electrical length of the second parasitic branch 16 is 1/4 of the wavelength corresponding to a certain frequency located between the lowest frequency of the preset frequency band and the second low-frequency.

In some embodiments, the radiating branch 11 is parallel to the first parasitic branch 15 and the second parasitic branch 16.

Further, since the first parasitic branch 15 and the radiating branch 11 are magnetically coupled, and the equivalent electrical length of the radiating branch 11 meets the resonance requirement of the preset frequency band, the resonance frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the preset frequency band and the second high frequency, so that the current at the second high frequency in the radiating branch 11 and the first parasitic branch 15 will be inverted, and since the radiating branch 11 is parallel to the first parasitic branch 15, the directions of the current at the second high frequency in the radiating branch 11 and the first parasitic branch 15 are opposite, so that the electromagnetic wave signals of the second high frequency generated by the radiating branch 11 and the first parasitic branch 15 cancel each other, which is equivalent to that the antenna assembly 1 has no signal at the second high frequency, and the radiation efficiency is almost zero, so as to form a second high frequency radiation zero. In addition, since the second parasitic branch 16 is electrically coupled to the radiation branch 11, and since the resonant frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low frequency band, the currents of the radiation branch 11 and the second parasitic branch 16 at the second low frequency band will be inverted, and since the radiation branch 11 is substantially parallel to the second parasitic branch 16, the directions of the currents of the radiation branch 11 and the second parasitic branch 16 at the second low frequency band are opposite, and the generated electromagnetic wave signals cancel each other, which is equivalent to that the antenna assembly 1 as a whole has no electromagnetic wave signal at the second low frequency band, and the radiation efficiency is almost zero, thereby forming a second low frequency radiation zero.

Wherein the radiation branch 11 is parallel to the first parasitic branch 15 and the second parasitic branch 16, only for better implementation of the radiation zero. In some embodiments, the radiating branch 11 may not be parallel to the first parasitic branch 15 and the second parasitic branch 16, and only the current at the second high-frequency in the radiating branch 11 and the first parasitic branch 15 needs to be inverted, so that the phase of the electromagnetic wave signal radiated to the second high-frequency in the free space through the radiating branch 11 and the first parasitic branch 15 may be inverted, so that the second high-frequency radiation zero point can be basically realized. Likewise, the second low frequency radiation zero point can be basically realized by inverting the phases of the electromagnetic wave signals of the second low frequency radiated into the free space through the radiation branch 11 and the second parasitic branch 16, respectively, only by inverting the currents of the radiation branch 11 and the second parasitic branch 16 at the second low frequency.

The radiation branches 11, the first parasitic branches 15, and the second parasitic branches 16 are stripe shapes, and the radiation branches 11 are substantially parallel to the first parasitic branches 15 and the second parasitic branches 16, which may mean that the extension directions of the radiation branches 11, the first parasitic branches 15, and the second parasitic branches 16 are substantially parallel. The extending directions of the radiating branch 11, the first parasitic branch 15, and the second parasitic branch 16 may be the extending directions of the longest sides of the radiating branch 11, the first parasitic branch 15, and the second parasitic branch 16.

In some embodiments, the radiating branch 11, the first parasitic branch 15, and the second parasitic branch 16 may be straight or bent bars. When the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 are straight, the longest sides of the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 may be the longest straight sides of the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16. When the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 are bent bars, the longest sides of the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 may be the longest bent line sides of the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 extending in the bending direction.

Herein, the radiation branch 11 is parallel to the first parasitic branch 15 and the second parasitic branch 16, which means substantially parallel, but not strictly parallel, for example, an angle between the radiation branch 11 and the extending directions of the first parasitic branch 15 and the second parasitic branch 16 is within a certain angle range, for example, 30 °, and may be regarded as substantially parallel.

Referring to fig. 6, a schematic diagram of magnetic field coupling between the radiating branch 11 and the first parasitic branch 15 of the antenna assembly 1 to generate a phase difference at a second high frequency in some embodiments of the present application is shown.

When magnetic field coupling occurs between two branches, the two branches are equivalent to series connection of an inductor. As shown in fig. 6, the radiation branch 11 and the first parasitic branch 15 are coupled by a magnetic field, which is equivalent to connecting an inductor L0 in series, and the inductor generates a phase difference of-90 °.

The feed source 12 specifically generates a feed signal to the feed point F1, excites the radiation branch 11 to operate in a preset frequency band, and excites the first parasitic branch 15 and the second parasitic branch 16 through coupling of the radiation branch 11, that is, can be regarded as coupling the feed signal to be transmitted from the radiation branch 11 to the first parasitic branch 15 and the second parasitic branch 16, where the feed signal may be an ac signal with a corresponding frequency, and after the radiation branch 11 and the first parasitic branch 15 and the second parasitic branch 16 are fed, the currents in the radiation branch 11 and the first parasitic branch 15 and the second parasitic branch 16 are described above.

In fig. 6 a first path P1 of the feed signal generated by the feed 12 conducted through the radiating branch 11 and a second path P2 conducted through the radiating branch 11 and the first parasitic branch 15 are schematically shown. Wherein the first path P1 is illustrated with solid arrows and the second path P2 is illustrated with dashed arrows. Wherein, at a second high frequency at which the antenna assembly 1 operates, the frequency of the feed signal may be the second high frequency.

When the equivalent electric length of a certain branch is higher than the frequency of the conducted feed signal, the equivalent electric length of the branch is smaller than 1/4 of the wavelength corresponding to the feed signal, and when the feed signal is conducted through the branch, the phase is advanced by 90 degrees, and a phase difference of +90 degrees is generated. Correspondingly, when the resonance frequency corresponding to the equivalent electrical length of a certain branch is lower than the frequency of the conducted feed signal, the equivalent electrical length of the branch is larger than 1/4 of the wavelength corresponding to the feed signal, and when the feed signal is conducted through the branch, the phase is delayed by 90 degrees, so that a phase difference of-90 degrees is generated. When the resonance frequency corresponding to the equivalent electrical length of a certain branch is equal to the frequency of the conducted feed signal, namely, the branch resonates at the moment, and no phase difference is generated when the feed signal is conducted through the branch.

When the initial phase of the feed signal output by the feed source 12 is set to be 0 ° and the frequency is the second high frequency, the equivalent electrical length of the radiating branch 11 meets the resonance requirement of the preset frequency band, and the equivalent electrical length of the radiating branch 11 is greater than 1/4 of the wavelength corresponding to the second high frequency because the preset frequency band is lower than the second high frequency, so that the phase of the radiating branch 11 lags by 90 ° when the feed signal is conducted, that is, the phase of the feed signal is generated by-90 °, and therefore, the phase of the feed signal after passing through the first path P1 is finally-90 °. And because the radiation branch 11 and the first parasitic branch 15 are coupled by a magnetic field, which is equivalent to connecting an inductance L0 in series, the inductance generates a phase difference of-90 degrees, and thus, when the feed signal is coupled and conducted to the first parasitic branch 15, a phase difference of-90 degrees is generated. And since the resonance frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the preset frequency band and the second high frequency and is also lower than the second high frequency, a phase difference of-90 ° is also generated, and thus, the phase of the feeding signal passing through the second path P2 is finally-90 ° + -90 ° + -90 ° = -270 °.

Thus, the phases of the electromagnetic wave signals emitted into free space through the first path P1 and said second path P2 will be-90 ° and-270 °, respectively, exhibiting a phase difference of 180 °, i.e. an inversion.

It can be seen that, when the equivalent electrical length of the radiating branch 11 meets the resonance requirement of the preset frequency band and the resonance frequency corresponding to the equivalent electrical length of the first parasitic branch 15 is located between the preset frequency band and the second high-frequency band, the first parasitic branch 15 and the radiating branch 11 are magnetically coupled, so that currents at the second high-frequency band in the radiating branch 11 and the first parasitic branch 15 are inverted.

Referring to fig. 7, a schematic diagram of magnetic field coupling between the radiating branch 11 and the second parasitic branch 16 of the antenna assembly 1 to generate a phase difference at a second low frequency in some embodiments of the present application is shown.

When electric field coupling occurs between two branches, the two branches are equivalent to a capacitor connected in series. As shown in fig. 7, the radiation branch 11 and the second parasitic branch 16 are coupled by an electric field, which is equivalent to a capacitor C0 connected in series, and the capacitor generates a phase difference of +90°.

In fig. 7, a first path P1 of the feed signal generated by the feed 12 conducted through the radiating branch 11 and a third path P3 conducted through the radiating branch 11 and the second parasitic branch 16 are illustrated. Wherein the first path P1 is illustrated with solid arrows and the third path P3 is illustrated with dashed arrows. Wherein, when the antenna assembly 1 is operated at a second low frequency, the frequency of the feed signal may be the second low frequency.

When the initial phase of the feed signal output by the feed source 12 is set to be 0 ° and the frequency is the second low frequency, the equivalent electrical length of the radiation branch 11 meets the resonance requirement of the preset frequency band, and the equivalent electrical length of the radiation branch 11 is smaller than 1/4 of the wavelength corresponding to the second low frequency because the preset frequency band is higher than the second low frequency, so that the phase of the radiation branch 11 is advanced by 90 ° when the feed signal is conducted, that is, the phase of the feed signal is generated by +90°, and therefore, the phase of the feed signal after passing through the first path P1 is finally +90 °. Because of the electric field coupling between the radiation branch 11 and the second parasitic branch 16, which is equivalent to connecting a capacitor C0 in series, as described above, the capacitor may generate a phase difference of +90°, and thus, when the feed signal is coupled to the second parasitic branch 16, a phase difference of +90° is generated. Since the resonant frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low frequency band and is also higher than the second low frequency band, a +90° phase difference is also generated, and thus, the phase of the feeding signal passing through the third path P3 is finally 90 ° +90 ° +90= +270 °.

Thus, the phases of the current/feed signals conducted through the first path P1 and the third path P3 are +90° and +270° respectively, exhibiting a phase difference of 180 °, i.e., an inversion phase.

It can be seen that, when the equivalent electrical length of the radiating branch 11 meets the resonance requirement of the preset frequency band and the resonance frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low-frequency band, when the second parasitic branch 16 is electrically coupled with the radiating branch 11, the currents at the second low-frequency band in the radiating branch 11 and the first parasitic branch 15 will be inverted.

Wherein, as shown in fig. 1, the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 may be substantially straight.

In some embodiments, the radiating branch 11, the first parasitic branch 15, and the second parasitic branch 16 may also be bent strips, i.e., substantially "L" -shaped, to effectively reduce the overall volume.

Referring to fig. 8, a more specific structural diagram of the antenna assembly 1 according to some embodiments of the present application is shown. In which a more specific structural configuration of the radiating stub 11, the first parasitic stub 15 and the second parasitic stub 16 in the antenna assembly 1 in some embodiments is illustrated in fig. 8.

As shown in fig. 8, the radiating stub 11 includes a main stub 111, a feed stub 112, and a ground stub 113, one end of the main stub 111 is a first end 11a of the radiating stub 11, the other end of the main stub 111 is connected to the feed stub 112 and the ground stub 113, the feed point F1 is disposed at the feed stub 112, one end of the ground stub 113 not connected to the main stub 111 is a second end 11b of the radiating stub 11, the first lumped element 13 and the second lumped element 14 are connected between the ground stub 113 and the ground, and the main stub 111 is parallel to the first parasitic stub 15 and the second parasitic stub 16.

That is, in some embodiments, the radiating stub 11 may include a main stub 111, a feed stub 112, and a ground stub 113 in some embodiments, where the feed stub 112 is primarily used for feeding, corresponding to the function of forming a part of a feed connection. And the ground stub 113 is mainly used for connection to ground, the first lumped element 13 and the second lumped element 14 are therefore connected between the ground stub 113 and ground. Thus, the aforementioned first lumped element 13 is connected between the second end 11b and ground, and the second lumped element 14 is connected between the second end 11b and ground, in particular between the ground stub 113 located at the second end 11b of the radiating stub 11.

In some embodiments, the main branch 111 of the radiating branch 11 mainly plays a role of radiation, so the equivalent electrical length of the radiating branch 11 is mainly the equivalent electrical length of the main branch 111. That is, in some embodiments, the equivalent electrical length of the main branch 111 may be λ ₁ 4, wherein the lambda ₁ And the wavelength corresponding to the preset frequency band is obtained.

In some embodiments, the main branch 111 is parallel to the first parasitic branch 15 and the second parasitic branch 16, that is, the aforementioned radiating branch 11 is parallel to the first parasitic branch 15 and the second parasitic branch 16, mainly referring to the main branch 111 being parallel to the first parasitic branch 15 and the second parasitic branch 16.

In some embodiments, the main branch 111, the feed branch 112, and the ground branch 113 are integrally formed conductive structures. Obviously, in other embodiments, the main branch 111, the feeding branch 112 and the grounding branch 113 may be connected together by welding, conductive glue bonding, or the like.

Wherein, as shown in fig. 8, the main branch 111 further includes a first branch portion 1111 and a second branch portion 1112, the first branch portion 1111 and the second branch portion 1112 are vertically connected, the second branch portion 1112 is connected with the feeding branch 112 and the grounding branch 113, and the second branch portion 1112 is the same as the extension direction of the feeding branch 112. As shown in fig. 8, the first parasitic branch 15 includes a first parasitic main branch 151 and a first parasitic ground branch 152, and the first parasitic main branch 151 and the first parasitic ground branch 152 are vertically connected and respectively parallel to the first branch portion 1111 and the second branch portion 1112; the second parasitic branch 16 includes a second parasitic main branch 161 and a second parasitic ground branch 162, and the second parasitic main branch 161 and the second parasitic ground branch 162 are vertically connected and also respectively parallel to the first branch portion 1111 and the second branch portion 1112.

That is, in some embodiments, the main branch 111 of the radiation branch 11 is substantially in an "L" structure, the first parasitic branch 15 and the second parasitic branch 16 are also substantially in an "L" structure, the main branch 111 is parallel to the first parasitic branch 15 and the second parasitic branch 16, specifically, the first branch portion 1111 and the second branch portion 1112 are parallel to the first parasitic main branch 151 and the first parasitic ground branch 152 of the first parasitic branch 15, respectively, and are parallel to the second parasitic main branch 161 and the second parasitic ground branch 162 of the second parasitic branch 16, respectively.

Thus, in some embodiments, the main branch 111 of the radiating branch 11 has a substantially "L" structure, and the first parasitic branch 15 and the second parasitic branch 16 also have substantially "L" structures, so that the overall size of the antenna assembly 1 can be effectively reduced while ensuring that the electrical length meets the requirements, which is advantageous for volume miniaturization.

In some embodiments, as shown in fig. 8, the second parasitic main branch 161 is formed with a notch K1 to increase the equivalent electrical length of the second parasitic branch 16.

As mentioned above, the resonance frequency corresponding to the equivalent electrical length of the second parasitic branch 16 is located between the preset frequency band and the second low frequency band, that is, between the lowest frequency in the preset frequency band and the second low frequency band, so that the equivalent electrical length of the second parasitic branch 16 needs to be greater than the equivalent electrical lengths of the radiation branch 11 and the first parasitic branch 15, and therefore, by forming the notch K1 in the second parasitic main branch 161, the equivalent electrical length of the second parasitic branch 16 can be increased without increasing the overall size of the second parasitic branch 16, which is also beneficial to the miniaturization of the volume.

The number of the notches K1 formed on the second parasitic main branch 161 may be at least one, as shown in fig. 8, the number of the notches K1 formed on the second parasitic main branch 161 may be two, that is, the first notch K11 and the second notch K12 are included, where the size of the first notch K11 is greater than the size of the second notch K12, and the first notch K11 may be a notch formed from one side of the second parasitic main branch 161 and is close to the second parasitic grounding branch 162, and the second notch K12 is a notch formed from the other side of the second parasitic main branch 161 and is located at an end of the second parasitic main branch 161 far from the second parasitic grounding branch 162.

The end of the second parasitic main branch 161 away from the second parasitic ground branch 162 is the second open end O2 of the second parasitic branch 16.

Thus, by the notch K1 formed in the second parasitic main branch 161, a curved path for the flow of the power can be formed, and the equivalent electrical length can be increased.

It is obvious that fig. 8 is only an example, and the second parasitic main branch 161 may be notched elsewhere, or notched with different dimensions, to increase the equivalent electrical length.

In some embodiments, as shown in fig. 8, the first parasitic branch 15 and the second parasitic branch 16 are disposed on the same side of the radiation branch 11, and the first parasitic branch 15 is located between the radiation branch 11 and the second parasitic branch 16 and is spaced apart from both the radiation branch 11 and the second parasitic branch 16.

Wherein, as described above, since the main branch 111 of the radiation branch 11 further includes the first branch portion 1111 and the second branch portion 1112, the first branch portion 1111 and the second branch portion 1112 are vertically connected, the second branch portion 1112 is connected with the feeding branch 112 and the grounding branch 113, and the second branch portion 1112 is the same as the extension direction of the feeding branch 112, the second branch portion 1112 and the feeding branch 112 are larger in size as a whole. Therefore, the space surrounded by the "L" shaped structure formed by the first branch 1111 and the second branch 1112 and the feeding branch 112 is large, so that the first parasitic branch 15 and the second parasitic branch 16 can be disposed in the space, which is advantageous for miniaturization of the whole volume.

As shown in fig. 8, the first parasitic branch 15 and the second parasitic branch 16 are disposed on the same side of the radiating branch 11, specifically, on a side of a bending direction of the "L" shaped bending structure formed by the radiating branch 11, that is, on a side of a space surrounded by the "L" shaped structure formed by the first branch portion 1111 and the second branch portion 1112 and the feeding branch 112.

Wherein the first parasitic branch 15 is located between the radiation branch 11 and the second parasitic branch 16, it is ensured that the first parasitic branch 15 is closer to the feeding point F1 of the radiation branch 11, and that magnetic field coupling occurs between the first parasitic branch 15 and the radiation branch 11.

Wherein, as shown in fig. 8, the first open end O1 of the first parasitic branch 15 is also relatively close to the first end 11a of the radiating branch 11, which is the open end, but because the first parasitic branch 15 has undergone magnetic field coupling, and the first parasitic branch 15 is relatively short compared to the first branch portion 1111 of the main branch 111 of the radiating branch 11, as shown in fig. 8, the second parasitic main branch 161 of the second parasitic branch 16 extends through the first branch portion 1111 of the main branch 111 of the radiating branch 11, that is, extends through the first end 11a of the radiating branch 11, which is the open end, and is further located in the electric field radiation area of the first end 11a, so that electric field coupling occurs between the second parasitic branch 16 and the radiating branch 11.

Referring to fig. 9, another more specific structure of the antenna assembly 1 according to some embodiments of the present application is shown. In some embodiments, the first parasitic branch 15 and the second parasitic branch 16 may be disposed on two sides of the radiating branch 11, the radiating branch 11 is disposed between the first parasitic branch 15 and the second parasitic branch 16, and spaced apart from the first parasitic branch 15 and the second parasitic branch 16, and the second parasitic ground branch 162 of the second parasitic branch 16 is closer to the feed point F1 of the radiating branch 11 than the first parasitic ground branch 152 of the first parasitic branch 15, and the second open end O2 of the second parasitic branch 16 is closer to the first end 11a of the radiating branch 11, which is an open end.

That is, in some embodiments, the first parasitic branch 15 and the second parasitic branch 16 may be disposed on two sides of the radiating branch 11, where the first parasitic ground branch 152 of the first parasitic branch 15 is only required to be closer to the feed point F1 of the radiating branch 11 than the second parasitic ground branch 162 of the second parasitic branch 16, so that magnetic field coupling between the first parasitic branch 15 and the radiating branch 11 is ensured, and since the radiating branch 11 is located in parallel with both the first parasitic branch 15 and the second parasitic branch 16, and the second open end O2 of the second parasitic branch 16 is close to the first end 11a of the radiating branch 11, which is an open end, the second parasitic branch 16 is also ensured to be electrically coupled with the radiating branch 11.

The difference between the structure of the antenna assembly 1 shown in fig. 9 and the structure of the antenna assembly 1 shown in fig. 8 is that the first parasitic branch 15 and the second parasitic branch 16 are respectively disposed on two sides of the radiating branch 11, and other structures are the same as the structure of the antenna assembly 1 shown in fig. 8, and particularly, see the relevant content of fig. 8.

In some embodiments, as shown in fig. 8 and 9, the antenna assembly 1 further includes a dielectric substrate 17, and the radiation branch 11, the first parasitic branch 15, the second parasitic branch 16, and the like are disposed on the dielectric substrate 17.

The radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 may be LDS (laser formed) metal structures formed on the dielectric substrate 17 by a laser technology. The LDS antenna is a metal antenna pattern directly plated on the dielectric substrate 17 by laser technology. Alternatively, the radiating stub 11, the first parasitic stub 15, and the second parasitic stub 16 may also be FPC (flexible printed circuit, flexible circuit board) metal structures disposed on the dielectric substrate 17. The FPC antenna refers to a metal antenna pattern formed on the FPC, and the FPC antenna may be fixed on the dielectric substrate 17 by bonding, embedding, soldering, or the like.

The dielectric substrate 17 is made of an insulating material, such as a plastic material, a resin material, a ceramic material, or the like.

As shown in fig. 8 and 9, the radiation branch 11, the first parasitic branch 15, the second parasitic branch 16, and the like are all disposed on the same surface of the dielectric substrate 17.

The dielectric substrate 17 may be substantially plate-shaped, and the surface of the dielectric substrate 17 may be specifically a surface of the dielectric substrate 17 having the largest area.

Referring to fig. 10, a more specific schematic structure of the antenna assembly 1 according to some embodiments of the present application is shown. As shown in fig. 10, in some embodiments, the radiating stub 11, the first parasitic stub 15, and the second parasitic stub 16 may also be disposed on two opposing surfaces of the dielectric substrate 17. For example, as shown in fig. 10, the radiation stub 11 and the first parasitic stub 15 are disposed on one surface of the dielectric substrate 17, and the second parasitic stub 16 is disposed on the other surface of the dielectric substrate 17.

Thus, in some embodiments, even if the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 are disposed on different surfaces of the dielectric substrate 17, due to the small thickness of the dielectric substrate 17, the magnetic field coupling and the electric field coupling between the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 may still be achieved without being greatly affected, as long as the structural positional relationship among the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 still satisfies the aforementioned relationship, and the magnetic field coupling between the radiation branch 11 and the first parasitic branch 15, and the electric field coupling between the radiation branch 11 and the second parasitic branch 16 may still be achieved.

Wherein, the thickness of the dielectric substrate 17 may be a dimension in a direction perpendicular to a surface of the dielectric substrate 17 having the largest area.

In some embodiments, the difference between fig. 10 and fig. 8 is that the second parasitic branch 16 is disposed on the other surface of the dielectric substrate 17, as shown by the dashed line in fig. 10. The first parasitic branch 15 is located between the radiation branch 11 and the second parasitic branch 16, and for the structure shown in fig. 10, it may also refer to that the first parasitic branch 15 is located between projections of the radiation branch 11 and the second parasitic branch 16 on the surface where the radiation branch 11 is located.

In some embodiments, when the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 are disposed on two opposite surfaces of the dielectric substrate 17, the structural positional relationship among the radiation branch 11, the first parasitic branch 15, and the second parasitic branch 16 may also be a structural positional relationship between a branch on the main surface and a branch projection on the main surface after a branch projection is formed by taking a certain surface as the main surface and projecting a branch not on the main surface onto the main surface.

In some embodiments, the frequency range of the preset frequency band is 2.2 GHz-2.5 GHz. Obviously, the frequency range of the preset frequency band may be any other frequency range, for example, a frequency range of a low-frequency band, for example, 700 MHz-1000 MHz, and so on.

Referring to fig. 11, a schematic diagram of a return loss curve of an antenna assembly 1 according to some embodiments of the present application is shown. Fig. 11 may be a schematic diagram of a return loss curve obtained by performing a simulation test by taking the antenna assembly 1 shown in fig. 8 as an example, which operates in a preset frequency band.

Fig. 11 shows a return loss curve S11. Wherein, as shown in fig. 8, when the first high-frequency radiation zero is formed by the first lumped element 13 and the second high-frequency radiation zero is formed by the first parasitic branch 15, and when the first low-frequency radiation zero is formed by the second lumped element 14 and the second low-frequency radiation zero is formed by the second parasitic branch 16, the frequency range of the return loss lower than-6 dB is approximately 2.2GHz to 2.5GHz.

The lower the return loss of a certain frequency band, the better the radiation performance of the antenna assembly 1 in the frequency band, the higher the radiation efficiency, and in general, the better the radiation performance when the return loss is lower than-6 dB. Therefore, as can be seen from fig. 11, when the first high-frequency radiation zero is formed by the first lumped element 13 and the second high-frequency radiation zero is formed by the first parasitic branch 15, and when the first low-frequency radiation zero is formed by the second lumped element 14 and the second low-frequency radiation zero is formed by the second parasitic branch 16, it is possible to have a lower return loss and a better antenna radiation performance in a preset frequency band having a frequency range of 2.2GHz to 2.5GHz.

Fig. 12 is a schematic diagram showing another radiation efficiency curve of the antenna assembly 1 according to some embodiments of the present application. Fig. 12 is a schematic diagram of radiation efficiency curves obtained by performing simulation test on the antenna assembly 1 shown in fig. 8 operating in a preset frequency band.

In fig. 12, the radiation efficiency curve Sr2 is schematically shown, and as mentioned above, forming a radiation zero at a certain frequency means that the radiation efficiency at the frequency is very low, and is approximately zero, where the radiation zero is also the trough point of the radiation efficiency, that is, the trough point of the radiation efficiency curve. As shown in fig. 12, the antenna assembly 1 in the present application, in which the first high-frequency radiation zero is formed by the first lumped element 13 and the second high-frequency radiation zero is formed by the first parasitic branch 15, and in which the first low-frequency radiation zero is formed by the second lumped element 14 and the second low-frequency radiation zero is formed by the second parasitic branch 16, four radiation efficiency dips, that is, four radiation zero points, occur. Specifically, the first high-frequency radiation zero H10 and the second high-frequency radiation zero H20 distributed on the high-frequency side of the preset frequency band, and the first low-frequency radiation zero L10 and the second low-frequency radiation zero L20 distributed on the low-frequency side of the preset frequency band are shown in fig. 12.

As can be seen from the radiation efficiency curve Sr2 of fig. 12, the frequency corresponding to the first high-frequency radiation zero H10, that is, the first high-frequency is approximately 2.62GHz, the frequency corresponding to the second high-frequency radiation zero H20, that is, the second high-frequency is approximately 2.77GHz, and the frequency interval between the second high-frequency radiation zero H10 and the highest frequency 2.5GHz of the preset frequency band is smaller than the preset frequency interval. The frequency corresponding to the first low-frequency radiation zero L10, that is, the first low-frequency is approximately 1.96GHz, and the frequency corresponding to the second low-frequency radiation zero L20, that is, the second low-frequency is approximately 2.1GHz, and the frequency interval between the second low-frequency radiation zero L10 and the lowest frequency 2.2GHz of the preset frequency band is smaller than the preset frequency interval.

As mentioned above, when a certain frequency is the radiation zero point, the radiation efficiency in a certain frequency range around the surrounding is pulled down to a lower value. As shown in fig. 12, compared to the radiation efficiency graph shown in fig. 3, in fig. 12, since the second high-frequency radiation zero H20 is further formed by the first parasitic branch 15 and the second low-frequency radiation zero L20 is further formed by the second parasitic branch 16, the radiation efficiency corresponding to the first high-frequency radiation zero H10 is approximately-28 dB, the radiation efficiency corresponding to the first low-frequency radiation zero L10 is already substantially equal to the radiation zero with the radiation efficiency of zero, the radiation efficiency corresponding to the second high-frequency radiation zero H20 is approximately-26 dB, the radiation efficiency corresponding to the second low-frequency radiation zero L20 is approximately-18 dB, and the radiation efficiency corresponding to the second low-frequency radiation zero L20 is already substantially equal to the radiation zero with the radiation efficiency of zero except for the radiation efficiency corresponding to the second low-frequency radiation zero L20.

And as shown in fig. 12, due to the presence of the first high-frequency radiation zero H10 and the second high-frequency radiation zero H20, the radiation efficiency in the frequency range of about 2.6GHz to 2.9GHz is lower than the preset radiation efficiency value, for example-17 dB, and due to the presence of the first low-frequency radiation zero L10 and the second low-frequency radiation zero L20, the radiation efficiency in the frequency range of about 1.7GHz to 2.1GHz is lower than the preset radiation efficiency value, for example-17 dB.

It can be seen that the antenna assembly 1 of the present application has good frequency selectivity, a stop band bandwidth and a stop band depth when the first high frequency radiation zero is formed by the first lumped element 13 and the second high frequency radiation zero is formed by the first parasitic branch 15, and the first low frequency radiation zero is formed by the second lumped element 14 and the second low frequency radiation zero is formed by the second parasitic branch 16, and the efficiency on both sides of the preset frequency band is lower than-17 dB, the stop band bandwidth is larger than 200MHz, and the minimum in-stop band efficiency is lower than-27 dB; meanwhile, the radiation efficiency in the preset frequency band is larger than-1.75 dB, the adjacent frequency bands of the preset frequency band are effectively restrained, and the radiation efficiency in the preset frequency band is effectively improved.

In some embodiments, when the second high-frequency radiation zero is further formed by the first parasitic branch 15, and when the second low-frequency radiation zero is further formed by the second parasitic branch 16, the first high-frequency radiation zero formed by the first lumped element 13 and the first low-frequency radiation zero formed by the second lumped element 14 have a certain offset compared with the one shown in fig. 3, but the offset is not large, and the first low-frequency radiation zero is further close to the lowest frequency of the preset frequency band, so that the frequency band selectivity can be effectively improved.

Wherein, as shown in fig. 12, in some embodiments, the first high-frequency is approximately 2.62GHz, and the frequency corresponding to the second high-frequency radiation zero H20, that is, the second high-frequency is approximately 2.77GHz, and the first high-frequency is lower than the second high-frequency; the frequency corresponding to the first low-frequency radiation zero L10, that is, the first low-frequency is approximately 1.96GHz, the frequency corresponding to the second low-frequency radiation zero L20, that is, the second low-frequency is approximately 2.1GHz, and the first low-frequency is lower than the second low-frequency. In other embodiments, the first high frequency may also be higher than the second high frequency and the first low frequency may also be higher than the second low frequency.

Please refer to fig. 13, which is a normalized radiation pattern of the antenna assembly 1 in some embodiments of the present application.

The normalized radiation pattern shown in fig. 13 may be obtained by performing a simulation test on the antenna assembly 1 shown in fig. 8 operating in a preset frequency band. Specifically, let the plane in which the antenna assembly 1 is located be an XOY plane (for example, as shown in fig. 16), that is, let the plane in which the radiation branch 11, the first parasitic branch 15, etc. of the antenna assembly 1 are located be an XOY plane, the direction perpendicular to the plane in which the antenna assembly 1 is located be the Z direction, and fig. 13 may be a normalized radiation pattern of XOZ plane that intercepts the three-dimensional radiation pattern. Wherein, the X direction may be a direction parallel to the extending direction of the first branch portion 1111 of the radiation branch 11, and the Y direction may be a direction perpendicular to the extending direction of the first branch portion 1111 of the radiation branch 11.

As can be seen from fig. 13, the main radiation direction, i.e. the beam direction, of the antenna assembly 1 is mainly two opposite directions in the X direction, i.e. in the two directions of 0 ° and 180 ° in fig. 11, which are also both ends in the extending direction of the first stub portion 1111, thus having good directivity.

Referring to fig. 14, another normalized radiation pattern of the antenna assembly 1 in some embodiments of the present application is shown.

The normalized radiation pattern shown in fig. 14 may also be obtained by performing a simulation test, for example, in which the antenna assembly 1 shown in fig. 8 operates in a preset frequency band. Specifically, fig. 14 is a normalized radiation pattern of the YOZ plane taken from the stereoscopic radiation pattern. Here, as described above, the X direction may be a direction parallel to the extending direction of the first branch portion 1111 of the radiation branch 11, and the Y direction may be a direction perpendicular to the extending direction of the first branch portion 1111 of the radiation branch 11.

As can be seen from fig. 14, on the YOZ plane, the beam directions of the antenna assembly 1 are relatively balanced, so that a certain omnidirectional radiation characteristic can be realized.

Therefore, in the antenna assembly 1 in the present application, the first high-frequency radiation zero point and the first low-frequency radiation zero point are formed on two sides of the preset frequency band respectively through the first lumped element 13 and the second lumped element 14 at one end of the radiation branch 11, and the radiation efficiency of the frequency band nearby the preset frequency band can be reduced through the first lumped element 13 and the second lumped element 14, and the radiation performance of the frequency band nearby the preset frequency band can be ensured by effectively realizing the suppression of the frequency band nearby the preset frequency band. Because the antenna component 1 integrates the filtering function, the suppression of the nearby frequency bands of the preset frequency band can be effectively realized without adding an additional independent filter, the radiation performance working in the preset frequency band is ensured, the cost is effectively saved, and the space is also saved.

In addition, when the antenna component 1 of the present application forms the second high-frequency radiation zero through the first parasitic branch 15 in addition to the first high-frequency radiation zero through the first lumped element 13, and forms the second low-frequency radiation zero through the second parasitic branch 16 in addition to the first low-frequency radiation zero through the second lumped element 14, the antenna component 1 can have better frequency selectivity, a stop band bandwidth and a stop band depth, the stop band bandwidths of which the efficiencies are lower than-17 dB on both sides of the preset frequency band are both greater than 200MHz, and the minimum in-stop band efficiency is lower than-27 dB; meanwhile, the radiation efficiency in the preset frequency band is larger than-1.75 dB, the adjacent frequency bands of the preset frequency band are effectively restrained, and the radiation efficiency in the preset frequency band is effectively improved.

Referring to fig. 15, a block diagram of an electronic device 100 according to some embodiments of the present application is shown. Wherein, as shown in fig. 15, the electronic device 100 may comprise an antenna assembly 1. The antenna assembly 1 may be the antenna assembly 1 in any of the foregoing embodiments.

Therefore, in the electronic device 100 of the present application, the filtering function is integrated through the antenna assembly 1 itself, and the suppression of the nearby frequency band of the preset frequency band can be effectively achieved without adding an independent filter, so as to ensure the radiation performance working in the preset frequency band.

Please refer to fig. 16, which is a schematic diagram illustrating a part of the internal structure of the electronic device 100. As shown in fig. 16, the electronic device 100 further includes a ground plate 2, and the ground plate 2 is used to provide a ground potential.

The ground may be the ground plate 2. For example, the first lumped element 13 and the second lumped element 14 may be connected between the second end 11b of the radiating stub 11 and the ground plane 2.

Wherein, in some embodiments, the ground plate 2 may be a middle frame of the electronic device 100.

As shown in fig. 16, at least the radiation stub 11 of the antenna assembly 1 is disposed adjacent to one end D1 of the ground plate 2. For example, the radiating stub 11, the first lumped element 13, the second lumped element 14, the first parasitic stub 15, the second parasitic stub 16, and the like of the antenna assembly 1 may be disposed in a region adjacent to the one end D1 of the ground plane 2, and the first lumped element 13, the second lumped element 14 may be directly connected to the end face of the one end D1 of the ground plane 2 to be grounded.

As shown in fig. 16, in some embodiments, when the antenna assembly 1 further includes a dielectric substrate 17, the dielectric substrate 17 may be stacked with the ground plane 2, and the target portion 171 of the dielectric substrate 17 extends beyond the end D1 of the ground plane 2, and the radiating branch 11, the first lumped element 13, the second lumped element 14, the first parasitic branch 15, and the second parasitic branch 16 of the antenna assembly 1 are disposed on the target portion 171 of the dielectric substrate 17. For example, the surface of the target portion 171 of the dielectric substrate 17 facing the ground plate 2.

When the dielectric substrate 17 and the ground plate 2 are stacked, the dielectric substrate 17 may be disposed on a side of the ground plate 2 facing away from the display screen, that is, the dielectric substrate 17 may be closer to the rear surface side of the electronic device 100 than the ground plate 2.

Fig. 16 and the foregoing views of fig. 1 may be schematic views from the display screen side of the electronic device 100.

Obviously, in some embodiments, the dielectric substrate 17 may also include only the target portion 171 located on the side of the end D1 of the ground plate 2, without being disposed in a stacked manner with the ground plate 2. For example, the dielectric substrate 17 may be fixed to a position corresponding to the end D1 of the ground plate 2 on the inner periphery of the frame of the electronic device 100 or to an end surface of the end D1 of the ground plate 2.

Please refer to fig. 17, which is a schematic plan view of the electronic device 100 according to some embodiments of the present application. As shown in fig. 17, the electronic device 100 includes a top end D11, a bottom end D12, and two side ends D13, where at least the radiating stub 11 of the antenna component 1 is disposed adjacent to one end D1 of the ground plate 2, and the end D1 of the ground plate 2 may be an end close to the top end D11 of the electronic device 100.

Accordingly, as shown in fig. 17, most of the structure of the antenna assembly 1 is located substantially at the top end D11 of the electronic device 100. It is obvious that in other embodiments, the end D1 of the ground plate 2 may be an end close to the bottom end D12 of the electronic device 100, or the end D1 of the ground plate 2 may be an end close to one of the side ends D13 of the electronic device 100, and most of the structure of the antenna assembly 1 may also be located substantially at the bottom end D12 or one of the side ends D13 of the electronic device 100.

As shown in fig. 17, the electronic device further includes a motherboard 3, and the feed source 12 and the like may be disposed on the motherboard 3. As shown in fig. 17, the electronic device 100 may include a middle frame 4, and as described above, the ground plate 2 may be the middle frame 4.

In some embodiments, as shown in fig. 17, the electronic device 100 may further include a frame 5, and in some embodiments, the radiating branch 11, the first parasitic branch 15, the second parasitic branch 16, and the like of the antenna assembly 1 may also be a plurality of branches formed on the frame 5 by being separated by a slit. For example, on a frame surface of the frame 5 facing the end surface of the end D1 of the ground plate 2, the radiation branch 11, the first parasitic branch 15, the second parasitic branch 16, and the like may be formed separately by a slit penetrating the frame surface, at a portion of the frame 5 near the end D1 of the ground plate 2. Wherein the gap may be filled with an insulating material while maintaining the integrity of the rim 5.

In some embodiments, the electronic device 100 further includes a memory, a battery, etc., which are not described in detail herein, since they are not related to the improvement of the present application.

The electronic device 100 of the present application may be any electronic device with an antenna, such as a mobile phone, a tablet computer, a notebook computer, and the like.

According to the electronic device 100 and the antenna assembly 1 thereof, one end of the radiation branch 11 is grounded through the first lumped element 13 and the second lumped element 14, and the first high-frequency radiation zero and the first low-frequency radiation zero are formed on two sides of the preset frequency band through the first lumped element 13 and the second lumped element 14 respectively, and the frequency interval between the frequency corresponding to the first high-frequency radiation zero and the highest frequency of the preset frequency band and the frequency interval between the frequency corresponding to the first low-frequency radiation zero and the lowest frequency of the preset frequency band are smaller than or equal to the preset frequency interval, so that the radiation efficiency of the nearby frequency band of the preset frequency band can be reduced, the suppression of the nearby frequency band of the preset frequency band can be effectively realized, and the radiation performance of the preset frequency band is ensured. Because the antenna component 1 integrates the filtering function, the suppression of the nearby frequency bands of the preset frequency band can be effectively realized without adding an independent filter, the radiation performance working in the preset frequency band is ensured, the cost is effectively saved, and the space is also saved. In addition, when the electronic device 100 and the antenna assembly 1 of the present application form the second high-frequency radiation zero through the first parasitic branch 15 in addition to the first high-frequency radiation zero through the first lumped element 13, and form the second low-frequency radiation zero through the second parasitic branch 16 in addition to the first low-frequency radiation zero through the second lumped element 14, the frequency selectivity is better, the stopband bandwidth and the stopband depth are better, the stopband bandwidths of which the efficiencies are lower than-17 dB at both sides of the preset frequency band are both greater than 200MHz, and the minimum in-stopband efficiency is lower than-27 dB; meanwhile, the radiation efficiency in the preset frequency band is larger than-1.75 dB, the adjacent frequency bands of the preset frequency band are effectively restrained, and the radiation efficiency in the preset frequency band is effectively improved.

Various embodiments of the present application are directed to structures that are not specifically described in some embodiments, and in no way conflict, reference may be made to the contents of corresponding structures in other embodiments.

The foregoing description is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and should be covered in the scope of the present application; embodiments of the present application and features of embodiments may be combined with each other without conflict. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (20)

1. An antenna assembly, the antenna assembly comprising:

the radiating branch comprises a first end, a second end and a feed point, wherein the first end is an open-circuit end;

the feed source is connected with the feed point and is used for exciting the radiation branch to work in a preset frequency band;

the first lumped element is connected between the second end and the ground and is used for forming a first high-frequency radiation zero point at a first high-frequency, wherein the first high-frequency is higher than the highest frequency of the preset frequency band, and the frequency interval between the first high-frequency and the highest frequency of the preset frequency band is smaller than or equal to the preset frequency interval;

And the second lumped element is connected between the second end and the ground and is used for forming a first low-frequency radiation zero point at a first low-frequency, wherein the first low-frequency is lower than the lowest frequency of the preset frequency band, and the frequency interval between the first low-frequency and the lowest frequency of the preset frequency band is smaller than or equal to the preset frequency interval.

2. The antenna assembly of claim 1, wherein the first lumped element and the second lumped element each comprise at least one capacitance and at least one inductance, the first lumped element being configured to cause the radiating branch to be impedance mismatched at the first high frequency to form a first high frequency radiation zero, the second lumped element being configured to cause the radiating branch to be impedance mismatched at the first low frequency to form a first low frequency radiation zero.

3. The antenna assembly of claim 2, wherein the first lumped element comprises a first capacitance and a first inductance in series between the second terminal and ground, and the second lumped element comprises a second capacitance and a second inductance in series between the second terminal and ground.

4. The antenna assembly of claim 1, wherein the first lumped element comprises a first capacitance and a first inductance in series between the second end and ground, the second lumped element comprises a second capacitance and a second inductance in series between the second end and ground, and a product of a capacitance value of the first capacitance and an inductance value of the first inductance is less than a product of a capacitance value of the second capacitance and an inductance value of the second inductance.

5. The antenna assembly of claim 2, wherein the predetermined frequency interval is 350MHz.

6. The antenna assembly of claim 2, further comprising a first parasitic stub coupled with the radiating stub and being magnetic field coupled, the first parasitic stub for forming a second high frequency radiation null at a second high frequency, wherein the second high frequency is higher than and less than or equal to a preset frequency interval from a highest frequency of the preset frequency band; the second parasitic branch is coupled with the radiation branch and is electric field coupling, and the second parasitic branch is used for forming a second low-frequency radiation zero point at a second low-frequency, wherein the second low-frequency is lower than the lowest frequency of the preset frequency band, and the frequency interval between the second low-frequency and the lowest frequency of the preset frequency band is smaller than or equal to the preset frequency interval.

7. The antenna assembly of claim 6, wherein the first parasitic branch includes a first ground end and a first open end, the second parasitic branch includes a second ground end and a second open end, the first ground end and the second ground end are grounded, wherein the first ground end of the first parasitic branch is closer to the feed point of the radiating branch than the second ground end, and the second open end of the second parasitic branch is adjacent to the first end of the radiating branch.

8. The antenna assembly of claim 7, wherein an equivalent electrical length of the radiating branch meets a resonance requirement of a preset frequency band, a resonance frequency corresponding to the equivalent electrical length of the first parasitic branch is located between the preset frequency band and the second high frequency, and a resonance frequency corresponding to the equivalent electrical length of the second parasitic branch is located between the preset frequency band and the second low frequency, and when the first parasitic branch is magnetically coupled with the radiating branch, currents at the second high frequency in the radiating branch and the first parasitic branch are inverted to form a second high frequency radiation zero; when the second parasitic branch is coupled with the radiation branch by an electric field, the current at the second low-frequency in the radiation branch and the second parasitic branch is reversed to form a second low-frequency radiation zero.

9. The antenna assembly of claim 8, wherein the radiating stub has an equivalent electrical length λ ₁ 4, said lambda ₁ For the wavelength corresponding to the preset frequency band, the equivalent electrical length of the first parasitic branch is lambda ₂ 4, wherein the lambda ₂ For the wavelength corresponding to the frequency between the preset frequency band and the second high-frequency, the equivalent electrical length of the second parasitic branch is lambda ₃ 4, wherein the lambda ₃ And the wavelength is the wavelength corresponding to the frequency between the preset frequency band and the second low-frequency.

10. The antenna assembly of claim 8, wherein the radiating branch is parallel to the first parasitic branch and the second parasitic branch.

11. The antenna assembly of claim 10, wherein the radiating stub comprises a main stub, a feed stub, and a ground stub, one end of the main stub being a first end of the radiating stub, the other end of the main stub being connected to the feed stub and the ground stub, the feed point being disposed at the feed stub, one end of the ground stub not connected to the main stub being a second end of the radiating stub, the first lumped element and the second lumped element being connected between the ground stub and the ground, the main stub being parallel to the first parasitic stub and the second parasitic stub.

12. The antenna assembly of claim 11, wherein the main branch includes a first branch portion and a second branch portion, the first branch portion and the second branch portion are vertically connected, the second branch portion is connected with the feed branch and the ground branch, and the second branch portion is the same as the feed branch in the extending direction; the first parasitic branch comprises a first parasitic main branch and a first parasitic grounding branch, and the first parasitic main branch and the first parasitic grounding branch are vertically connected and are respectively parallel to the first branch part and the second branch part; the second parasitic branch includes a second parasitic main branch and a second parasitic ground branch, which are vertically connected and are also respectively parallel to the first branch portion and the second branch portion.

13. The antenna assembly of claim 12, wherein the second parasitic main branch is notched to increase an equivalent electrical length of the second parasitic branch.

14. The antenna assembly of claim 7, wherein the first parasitic stub is located between the radiating stub and the second parasitic stub and is spaced apart from both the radiating stub and the second parasitic stub.

15. The antenna assembly of claim 7, further comprising a dielectric substrate, the radiating stub, the first parasitic stub, and the second parasitic stub being disposed on the dielectric substrate.

16. The antenna assembly according to any one of claims 1-15, wherein the frequency range of the predetermined frequency band is 2.2 GHz-2.5 GHz.

17. An electronic device comprising the antenna assembly of any of claims 1-16.

18. The electronic device of claim 17, further comprising a ground plate for providing a ground potential.

19. The electronic device of claim 18, wherein at least the radiating stub in the antenna assembly is disposed adjacent one end of the ground plate.

20. The electronic device of claim 19, wherein when the antenna assembly further comprises a dielectric substrate, the dielectric substrate is disposed in a stack with the ground plate, and a target portion of the dielectric substrate extends beyond the end of the ground plate, at least the radiating stub is disposed at the target portion of the dielectric substrate.