CN102760974B - Antenna and active antenna system - Google Patents

Abstract

The invention relates to the field of wireless communication, and discloses an antenna which comprises at least one row of unit oscillators and a feed network, wherein each row of unit oscillators comprises a plurality of unit oscillators, the feed network is used for providing the same power division weight for each unit oscillator in the same row of unit oscillators, and the distances between adjacent oscillators in the same row of unit oscillators are unequal. The invention also provides an active antenna system. The distance between adjacent oscillators in the same row of unit oscillators is designed to be unequal, and the feed network provides the same power division weight for each oscillator in the same row of unit oscillators, so that the feed network is simplified. And the realizability, manufacturability and stability of the antenna are improved.

Description

Antennas and Active Antenna Systems

technical field

The invention relates to the field of wireless communication, in particular to an antenna and an active antenna system.

Background technique

As shown in FIG. 1 , the existing antenna is composed of many columns of antennas, and each column of antennas is composed of many unit dipoles. In each row of antennas, due to the different positions of the individual unit dipoles, the middle unit dipole requires an increase in the power division weight to enhance the main lobe gain in the vertical plane; the edge unit dipoles require a reduced power division weight to suppress the vertical The sidelobe gain of the surface. In order to fit the antenna as a whole to meet the radiation characteristics (enhance the main lobe and suppress the side lobes), a feed network is introduced, so that the unit oscillators at different positions adopt different power division weights. Wherein, FIG. 1 only shows the unit oscillator of the antenna, and other parts (for example) the feeding network are not shown.

As shown in Figure 2, taking the single-frequency antenna as an example, all the unit oscillators transmit the same frequency, and the size of the oscillators is the same. The distance between adjacent oscillators (including the length of the oscillator and the length of the oscillator gap) in the unit oscillators of each column of the traditional antenna is equal. Through multiple power divisions in the feed network, the vibrator currents provided to different placement positions are different, thereby suppressing side lobes and meeting the radiation requirements in the vertical direction of the antenna. Wherein, FIG. 2 only shows a row of unit oscillators.

However, with the rapid development of the active antenna system (Active Antenna System, AAS), it brings the following problems: the radio frequency module is integrated in the AAS, which increases the number of nodes in the feed network of the antenna and increases the difficulty of AAS implementation. It brings great risks to the reliability, manufacturability, and stability of AAS; the further AAS broadband system integrates multiple standards, making the current distribution of the feeder network more and more complicated and cumbersome.

Contents of the invention

One aspect of the present invention provides an antenna to improve the reliability and stability of the antenna.

The antenna includes at least one column of unit oscillators and a feed network, wherein each column contains a plurality of unit oscillators, and the feed network is used to provide the same power division weight for each unit oscillator in the same column of unit oscillators , the spacing between adjacent unit vibrators in the same column is not equal.

Optionally, the spacing between adjacent unit oscillators in the same row of unit oscillators is adjustable.

Optionally, the power division weight of each unit oscillator is a current value provided by the feed network to each unit oscillator through a power division node.

Optionally, the distance between adjacent unit oscillators in the same row of unit oscillators is d=L ₁ /2+L ₂ /2, where L ₁ and L ₂ are respectively two adjacent unit oscillators in the column direction The length occupied by above is calculated by the following formula:

L=(I*L _{Known Antenna} )/I _{Known Antenna} , wherein I represents the power division weight value that the feed network supplies to the unit oscillator, and L _{Known Antenna} represents the area occupied by the unit oscillator in the column direction in the known antenna Length, I _{The known antenna} represents the power division weight of the unit oscillator in the known antenna.

Optionally, for the same column of unit oscillators, calculate the ratio of the length L occupied by each unit oscillator in the column direction to the sum of the lengths occupied by all the unit oscillators in the column, and multiply the ratio by the height of the corresponding known antenna , to obtain the optimized length L' occupied by each unit oscillator in the column direction;

Then according to:

d'=L'1/2+L'2/2

Calculating the optimized spacing between adjacent unit oscillators; or

The spacing of each vibrator in the unit vibrator of the same column is adjusted according to a certain ratio.

In the at least one row of unit oscillators, the distance between adjacent unit oscillators decreases gradually from both ends of the row of unit oscillators to the center.

Optionally, in the at least one row of unit oscillators, each unit oscillator is arranged symmetrically with respect to the center of the row of unit oscillators.

Optionally, the feed network provides the same current value to each unit oscillator in the same column through at least one power divider.

Optionally, the vibrators in the at least one row of unit vibrators have the same size.

Optionally, when the antenna includes multiple columns of unit dipoles, dipoles in the same column of dipoles have the same size, and dipoles in different columns of dipoles have different sizes.

Optionally, the density rules of the oscillators of the different row unit oscillators are different.

Optionally, the vibrators in the unit vibrators in the same column have different sizes.

Another aspect of the present invention also provides an active antenna system, which is characterized in that it includes the aforementioned antenna.

Optionally, the system further includes a radio frequency module connected to the antenna.

The present invention simplifies the feeding by designing the spacing between adjacent unit vibrators in the same row of unit vibrators to be unequal, and the feed network provides the same power division weight for each unit vibrator in the same row of unit vibrators. electricity network. And the realizability, manufacturability and stability of the antenna are improved.

Description of drawings

FIG. 1 is a schematic diagram of an existing antenna structure and its vertical radiation;

Fig. 2 is a schematic diagram of the structure of the unit vibrator in the existing antenna and its relationship with the feeding network;

Fig. 3 is a schematic diagram of the structure of the unit vibrator in the antenna of the present invention and its relationship with the feed network;

FIG. 4 shows the relationship between the distance between adjacent unit oscillators and the length of the unit oscillators.

Fig. 5 is a schematic structural diagram of a traditional equidistant antenna used for comparison and description;

Fig. 6 is a schematic diagram of the structure of the sparse unequal antenna of the present invention used for comparison and description;

Fig. 7 is a vertical plane radiation waveform diagram formed by the traditional antenna structure of Fig. 5 and the structure of the present invention;

Fig. 8 is a schematic structural diagram of the AAS single-frequency antenna system of the present invention;

Fig. 9 is a schematic diagram of the independent arrangement structure of high and low frequency unit vibrators in each column of the AAS broadband antenna system of the present invention;

Fig. 10 is a schematic diagram of the mixed layout structure of high and low frequency unit oscillators in each row in the AAS broadband antenna system of the present invention.

Detailed ways

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

The present invention provides an antenna, including at least one column of unit oscillators and a feed network, each column of unit oscillators contains a plurality of unit oscillators, and the feed network is used to provide the same power division for each unit oscillator in the same row of unit oscillators The weight value, the spacing between adjacent unit oscillators in the same row of unit oscillators is not equal.

The feed network can be connected to each row of unit oscillators through a coaxial cable, and the unit oscillators can be composed of two orthogonal oscillators, rod-shaped oscillators, or spiral oscillators.

Optionally, for each column of unit oscillators, the distance between adjacent oscillators gradually decreases from both ends of a column of unit oscillators to the center, and the oscillators are arranged symmetrically with respect to the center of the row of unit oscillators. The vibrator may be made of metal, and may be a half-wave vibrator, a full-wave vibrator or a 1/4 wavelength vibrator. The vibrator can be a rod vibrator or an orthogonal cross vibrator.

The feed network includes at least one power divider for distributing power division weights for the vibrator, preferably one, and other circuits for realizing power division can also be used to replace the power divider for distributing power division weights for the vibrator . If the feed network includes multiple power dividers, the multiple power dividers can be connected through coaxial cables.

As shown in Figure 3, the feed network includes a primary power divider, the power divider is an 8-way power divider, and the 8-way power divider is an equal power divider, through an equal power divider The same current value can be provided to eight unit oscillators in a single row, while the traditional feed network shown in Figure 2 includes three-stage power dividers, the first-stage power divider is a two-way power divider, and the second-stage power divider is a two-way power divider. The second-level power divider is two 2-way power dividers, and the third-level power divider is four 2-way power dividers. These six power dividers are all unequal power dividers. The power divider is used to provide different current values for the 8 unit oscillators in a single row, and at the same time, the parameters of the unequal power divider need to be designed according to the current value required by each unit oscillator, as shown in the feed network of the present invention shown in Figure 3 Compared with the traditional feed network shown in Figure 2, the number of network nodes is reduced, the structure of the feed network is simplified, and it is easy to design and implement.

The method for determining the pitch of the unit oscillators is described below through an embodiment.

Let the current density of each unit vibrator be D, and the unit is ampere/meter; the power distribution weight represents the current value provided by the node in the feed network to the vibrator (abbreviated as power distribution in the figure), represented by the letter I, and the unit is ampere.

As shown in Figure 4, the spacing between adjacent unit oscillators is d=L ₁ /2+L ₂ /2, where L ₁ and L ₂ are the lengths occupied by two adjacent unit oscillators in the column direction , L ₁ , L ₂ are calculated according to the power division weight of the traditional antenna having the same current density per unit length of the antenna and the length occupied by the unit oscillator in the column direction, and the unit is meter.

The unit vibrator can be placed arbitrarily within the length occupied by the column direction, and preferably, the unit vibrator is placed at a middle position within the length.

The formula for calculating the current density D is:

D=I/L (1)

For known antennas there are:

D _{known antenna} =I _{known antenna} /L _{known antenna} (2)

In order to ensure that the antenna meets the radiation requirements of the traditional antenna in the vertical direction, there are:

D _{antenna of the present invention} =D _{known antenna} (3)

So you can get:

L _{antenna of the present invention} =(I _{antenna of the present invention} *L _{known antenna} )/I _{known antenna} (4)

Among them, L _{the antenna of the present invention} represents the length occupied by the unit vibrator in the column direction in the present invention (including the length of the partial gap between the unit vibrator and the front and rear adjacent unit vibrators), and _{I the antenna of the present invention} represents the feeder in the antenna of the present invention. The electric network supplies the power division weight of the unit oscillator, and the L _{known antenna} indicates the length occupied by the corresponding unit oscillator in the column direction in the known antenna (including the length of the part of the gap between the unit oscillator and the front and rear adjacent unit oscillators ), the I _{known antenna} represents the power division weight of the corresponding unit oscillator in the known antenna. The preferred premise used in the formula (4) is not to change the transmission frequency of the known antenna, that is, the dipoles at the corresponding positions of the antenna of the present invention and the known antenna have the same size.

I _{antenna of the present invention} =I _total /m _{unit vibrator number} (5)

In the formula (5), I _{is always} the total current input to each column of antennas by the feed network, and _{the number of unit oscillators} in m is the number of antenna unit oscillators in the column. Formula (5) means that the total current is equally divided into each unit oscillator .

The values of the I _{antenna of the present invention} , _{the known antenna of} L and _{the known antenna of} I are all known, then according to formula (4), the L _{antenna of the present invention} can be calculated.

Because _{the antenna of the present invention} is calculated according to the power division weight of the known antenna having the same current density as the antenna of the present invention and the length occupied by the corresponding unit vibrator in the column direction, then for various known antennas, the present invention can be used The invention performs sparse and unequal spacing between unit oscillators, and can obtain the same radiation characteristics on the vertical radiation plane as the known antenna. Generally speaking, the known antenna used as the basis for the calculation is an antenna arranged at equal intervals between element oscillators, and the known antenna meets the requirements of vertical plane radiation characteristics (enhanced main lobe, suppressed side lobes).

Then according to:

The distance between dipoles of the i-th adjacent unit d _i =L _{antenna i/2 of the present invention} +L _{antenna i+1/2 of the present invention} (6) The distance between dipoles of adjacent units can be calculated.

However, if calculated according to formula (6), the height of the antenna may be lengthened or shortened. In order to keep the height of the antenna of the present invention the same as that of the known antenna, the calculated L _{of the antenna of} the present invention can be optimized, that is, for the same row of unit oscillators, the length and length occupied by each unit oscillator in the column direction are calculated. The ratio of the sum of the lengths occupied by all the unit oscillators in the above column is multiplied by the height of the corresponding known antenna to obtain the optimized length L' occupied by each unit oscillator in the column direction _{. The antenna of the present invention} .

Then according to:

The i-th adjacent unit vibrator spacing d _i =L' _{the antenna of the present invention i} /2+L' _{the antenna of the present invention i+1} /2 (6) can be calculated to obtain the optimized spacing between adjacent unit vibrators; Adjust the spacing of each vibrator in the same column of unit vibrators according to a certain ratio, that is, scale the spacing of each vibrator proportionally to flexibly adapt to antennas of different lengths; each column of unit vibrators can be adjusted and optimized in the above-mentioned manner.

In fact, the distance between adjacent oscillators is adjustable, and there are many arrangements, as long as the arrangement can enhance the main lobe, suppress side lobes, and meet the radiation requirements in the vertical direction.

In the following, the antennas of the prior art and the embodiments of the present invention are compared and described.

The traditional equidistant antenna structure is shown in Figure 5. Figure 5 only shows a row of unit oscillators, and the feed network requires multiple power division nodes (for example, power dividers). The weights are different, but the distance between adjacent oscillators is the same, which is 0.8324λ. The structure of the antenna of the present invention is shown in Figure 6. Figure 6 only shows a row of unit oscillators, and the feed network therein only needs one power division node, and the power division weights assigned to each oscillator are the same, and the phase The spacing between adjacent oscillators is different, so the power splitting nodes are reduced and the feed network is simplified. FIG. 7 shows a comparison of vertical section waveforms obtained by the structure of FIG. 5 and the structure of the present invention. It can be seen from FIG. 7 that the antenna of the present invention is similar to the conventional antenna in vertical section waveform diagram, and can also enhance the main lobe and suppress the side lobes to meet the vertical radiation requirements of the antenna.

As shown in FIG. 8 , the present invention provides a single-frequency single-mode active antenna system, including the antenna in the foregoing embodiments. The system also includes a radio frequency module connected to the antenna.

As shown in Figure 9, the present invention also provides a wide-band active antenna system, the schematic diagram of which is that the high-frequency and low-frequency unit vibrators are arranged independently in each column, n=4 in this embodiment, which is 4 columns of antennas, the system It may also include a radio frequency module (not shown) connected to the antenna. It can be seen from FIG. 9 that the unit oscillators of the same frequency column have the same size, while the unit oscillators of different frequency columns have different sizes. The sparse and unequal spacing design can be designed independently for different frequencies, and the sparse and unequal rules of the same frequency column can be the same.

As shown in Figure 10, the present invention provides another wide-band active antenna system. The structural diagram of this system shows that the high-frequency and low-frequency unit oscillators are arranged in each column. In this embodiment, n=4, which is 4 columns of antennas, and the same column The dipoles in the dipoles have different sizes, and the dipoles in each column that transmit the same frequency have the same size. The system may also include a radio frequency module (not shown) connected to the antenna. It can be seen from Figure 10 that although the high and low frequencies are mixed and deployed, it is still possible to design the density and unequal spacing according to the unit oscillators that emit the same frequency, and then intersperse the high and low frequencies according to the designed distance.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, some improvements and replacements can also be made, these improvements and replacements It should also be regarded as the protection scope of the present invention.

Claims (11)

1. An antenna, comprising at least one column of unit oscillators and a feed network, characterized in that each column contains a plurality of unit oscillators, and the feed network is used to provide the same work for each unit oscillator in the same row of unit oscillators Weighted value, the spacing between adjacent unit oscillators in the same row of unit oscillators is not equal, and the power division weight of each unit oscillator is provided to each unit by the feed network through the power division node The current value of the vibrator, the distance between adjacent unit vibrators in the same row of unit vibrators is d=L ₁ /2+L ₂ /2, L ₁ and L ₂ are respectively the two adjacent unit vibrators in the column direction The length occupied above is calculated by the following formula: L=(I*L _{known antenna} )/I _{known antenna} , wherein I represents the power division weight value of the feed network supplying the unit oscillator, and the L _{known antenna} Indicates the length occupied by the unit oscillator in the column direction in the known antenna, and I _{known antenna} indicates the power division weight of the unit oscillator in the known antenna. 2. The antenna according to claim 1, wherein the spacing between adjacent unit dipoles in the same row of unit dipoles is adjustable. 3. The antenna according to claim 1, wherein, for the same column of unit oscillators, the ratio of the length L occupied by each unit oscillator in the column direction to the sum of the lengths occupied by all the unit oscillators of the column is calculated, and the The ratio is multiplied by the height of the corresponding known antenna to obtain the optimized length L' occupied by each unit oscillator in the column direction; Then according to: d'＝L' ₁ /2+L' ₂ /2 Calculating the optimized spacing between adjacent unit oscillators; or The spacing of each vibrator in the unit vibrator of the same column is adjusted according to a certain ratio. 4 . The antenna according to claim 1 , wherein, in the at least one column of unit oscillators, the distance between adjacent unit oscillators decreases gradually from the two ends of the row of unit oscillators to the center. 5 . The antenna according to claim 4 , wherein, in the at least one column of unit dipoles, each unit dipole is arranged symmetrically with respect to the center of the column of unit dipoles. 6. The antenna according to any one of claims 1-5, characterized in that, the feed network provides the same current value to each unit oscillator in the same column through at least one power divider. 7. The antenna according to any one of claims 1-5, wherein the dipoles of the same frequency in the at least one row of unit dipoles have the same size. 8. The antenna according to any one of claims 1-5, wherein when the antenna includes multiple columns of unit elements, the size of the elements in the same column is the same, and the sizes of the elements in different columns are different. 9. The antenna according to claim 8, characterized in that the density rules of the element elements of different columns are different. 10. The antenna according to any one of claims 1-5, wherein the dipoles in the same row of dipoles are of different sizes. 11. An active antenna system, comprising the antenna according to any one of claims 1-10, the system further comprising a radio frequency module connected to the antenna.