CN111987442A - Radiation patch array and planar microstrip array antenna - Google Patents

Abstract

The invention provides a radiation patch array and a plane microstrip array antenna. The radiation patch array is composed of n columns of radiation patch linear arrays. The radiation patch line array consists of m rows of radiation patch units. The radiation patch unit includes a cross-type power division network and two rectangular patches. The cross-shaped power division network is a four-port structure. The left port and the right two ports are respectively connected to a rectangular patch, and the rectangular patch is excited in parallel; the upper port and the lower port are connected in series to the same column. The upper or lower port of the adjacent cross-type power division network. The radiating patch linear array excites the rectangular patch in the form of parallel serial feed, realizes the structural radiation superposition in the direction of the wide side of the rectangular real patch, reduces the length of the transmission line by one time, and reduces the size of the antenna, effectively reducing the cost of the antenna. At the same time, due to the reduced feed loss, the array noise performance will be improved, thereby increasing the radiation efficiency and the gain bandwidth performance of the array.

Description

Radiating patch array and planar microstrip array antenna

technical field

The invention relates to the technical field of microstrip antennas, in particular to a radiating patch array and a planar microstrip array antenna.

Background technique

In the field of modern mobile communication, as the core device of wireless microwave communication, the influence of its envelope characteristics and integration degree on the communication quality is more and more important. Compared with commonly used microwave antennas, microstrip antennas have the advantages of small size, light weight, simple fabrication, easy integration, and convenient conformality. Microstrip antennas can be widely used in airborne radar, satellite communication, mobile communication and satellite TV systems, significantly reducing the space occupied by communication equipment and improving the performance of communication equipment.

Due to the low unit gain, wide beam and low radiation efficiency of the microstrip antenna, in order to achieve the radiation performance of narrow beam and high gain, the microstrip plane is usually formed in the form of a parallel-feed or series-fed array of dielectric plates with low dielectric constant and low loss. array antenna. The parallel-fed microstrip array antenna requires a large number of transmission lines to design the feeding network, and the path loss is large. With the increase of the array, the gain of the antenna cannot be increased all the time, so it is not suitable to design a high-gain microstrip array antenna. The transmission line path of the series-fed microstrip array antenna is short and the loss is small, but the impedance bandwidth of the microstrip antenna is narrow, and the bandwidth of the general microstrip antenna is only about 0.6% to 3%.

The Chinese patent application publication number is CN110649394A, and the name of the invention is "a microstrip traveling wave array antenna using a multi-layer microstrip substrate series feeder network". N radiation patches of the strip-shaped microstrip line are connected by copper pillars , the second side of the first-layer microstrip substrate is provided with the first to N-1th impedance transformation lines, which are used to adjust the impedance matching between the first to the Nth radiation patches, and the relative bandwidth is 4%. However, as the frequency changes, the beam pointing of the antenna will deviate from the normal direction, resulting in signal drop. The metallized holes and copper pillars increase the complexity of the antenna structure, increase the processing cost and assembly difficulty.

The Chinese patent application publication number is CN210350087U, and the name of the invention is "An eccentrically fed planar microstrip array antenna includes a PCB dielectric board and a feed pin", and a radiating sheet is attached to the front of the PCB dielectric board. Microstrip feeders include horizontal microstrip feeders and vertical microstrip feeders. Multiple microstrip array elements are arranged in multiple rows and columns. All microstrip array elements are on the PCB medium board about the center short axis and center length respectively. Axisymmetric, can achieve fixed beam beam pointing. But the radiating element is only connected to one side of the feed line for each serial feed sub array, the bandwidth of the antenna is narrow and the loss is large.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a radiating patch array and a planar microstrip array antenna, which can solve the problems of high cost, narrow bandwidth and large loss of the microstrip array antenna in the prior art.

The purpose of this invention is to realize through the following technical solutions:

In a first aspect, the present invention provides a radiation patch array, which is composed of n rows of radiation patch linear arrays; the radiation patch linear array is composed of m rows of radiation patch units; the radiation patch units include a cross type power division network and two rectangular patches; the cross-shaped power division network is a four-port structure, including an upper port, a lower port, a left port and a right port; the left port and the right two ports are respectively connected to a rectangular patch The rectangular patch is excited in parallel; the upper port and the lower port are respectively connected in series to the upper port or the lower port of the adjacent cross-type power division network in the same column.

Further, the spacing between the radiation patch units is equal to the free space wavelength of 0.75 center frequency points, and the radiation patch units are in the form of magnetic boundary feeding.

In a second aspect, the present invention provides a planar microstrip array antenna, comprising a first dielectric substrate, a metal floor, and a second dielectric substrate; the back of the first dielectric substrate is in contact with one surface of the metal floor, so The other surface of the metal floor is in contact with one surface of the second dielectric substrate; the front surface of the first dielectric substrate is attached with the above-mentioned radiation patch array; the other surface of the second dielectric substrate is provided a feeding network; a metallized through hole is arranged at the center of the radiation patch array; the metallized through hole penetrates through the first dielectric substrate, the metal floor and the second dielectric substrate; Probes are provided, and the probes are used to connect the radiating patch array and the feeding network.

Further, the feeding network adopts the cascade connection of multi-stage T-type microstrip power dividers to form a feeding structure of 1 divided by n channels.

Further, the feeding network is a series feeding network or a parallel feeding network.

Further, the input port of the feeding network adopts a standard SMA joint structure.

Compared with the traditional microstrip feeding network, the planar microstrip array antenna of the present invention excites the rectangular patches in the form of parallel serial feed by the radiating patch linear array, and realizes structural radiation superposition in the direction of the wide side of the rectangular real patch. Reduce the length of the transmission line by 1 times, and reduce the size of the antenna at the same time, effectively reducing the cost of the antenna. At the same time, due to the reduced feed loss, the array noise performance will be improved, thereby increasing the radiation efficiency and the gain bandwidth performance of the array. A microstrip array antenna that realizes broadband, high efficiency and low side lobes.

Description of drawings

1 is a schematic structural diagram of a radiation patch array of the present invention;

2 is a schematic structural diagram of a planar microstrip array antenna of the present invention;

FIG. 3 is a schematic structural diagram of a series feeding network of the present invention;

4 is a schematic structural diagram of a parallel feeding network of the present invention;

5 is a gain-frequency curve diagram of the planar microstrip array antenna of the present invention;

FIG. 6 is a schematic diagram of the radiation direction of the center frequency of the planar microstrip array antenna of the present invention.

Detailed ways

The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

The embodiments of the present disclosure are described below through specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only some, but not all, embodiments of the present disclosure. The present disclosure can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments may be combined with each other under the condition of no conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

The radiation patch array of the present invention is shown in FIG. 1 . The radiation patch array 2 is composed of n rows of radiation patch linear arrays. The radiation patch line array consists of m rows of radiation patch units. The radiation patch unit includes a cross-type power division network 4 and two rectangular patches 3 . The cross-shaped power division network 4 is a four-port structure, including an upper port, a lower port, a left port and a right port. The left and right output ports excite the rectangular patch 3 in parallel, respectively, and the upper and lower ports are connected in series to the upper port or the lower port of the adjacent cross-type power division network 4 in the same column.

Further, the spacing between the radiating patch units 3 is equal to 0.75 free space wavelengths of the center frequency point of the available bandwidth of the antenna, the radiating patch unit 3 adopts the form of magnetic boundary feeding, and the radiating patch unit adopts the patch narrow side feeding. It can effectively reduce the influence of the antenna dispersion effect on the beam pointing offset after the array is formed, and can effectively reduce the frequency offset.

The planar microstrip array antenna of the present invention, as shown in FIG. 2 , includes a first dielectric substrate 7 , a metal floor 9 , and a second dielectric substrate 7 in order from top to bottom. The back surface of the first dielectric substrate 1 is in contact with one surface of the metal floor 9 , and the other surface of the metal floor 9 is in contact with one surface of the second dielectric substrate 7 . A radiation patch array 2 is attached to the front surface of the first dielectric substrate 1 . The feeding network 8 is provided on the other surface of the second dielectric substrate 7 . The center of the radiation patch array 2 is provided with a metallized through hole 5 , which penetrates the first dielectric substrate 1 , the metal floor 9 and the second dielectric substrate 7 . The metallized through hole 5 is provided with a probe, and the probe penetrates through the metallized through hole 5 and connects the radiation patch array 2 and the feeding network 8 .

Compared with the traditional microstrip feeding network, the radiating patch array excites the rectangular patch in the form of parallel serial feed, realizes the structural radiation superposition in the direction of the broad side of the rectangular patch, and reduces the length of the transmission line by one time, reducing the Cost of a planar microstrip array antenna. The development of a high-gain microstrip antenna array based on this feed structure topology improves the radiation efficiency and the gain-bandwidth performance of the array.

In the embodiment of the present invention, the first dielectric substrate 1 and the second dielectric substrate 7 are constructed using a 31 mil RO4350B substrate with a dielectric constant of 3.5.

Further, the feeding network 8 adopts the cascade connection of multi-stage T-type microstrip power dividers to form a feeding structure of 1 divided by n channels. The feeding network 8 is a series feeding network 6 or a parallel feeding network 9 . The input port 12 of the feeding network 8 adopts a microstrip line to standard SMA connector structure, which is convenient for connection with standard devices. The full name of SMA is Small A Type. The standard SMA connector is "external thread + hole" at one end and "internal thread + pin" at the other end.

Further, the width of the conversion section of the cross-shaped power division network 4 is designed according to the Taylor amplitude distribution required for sidelobe suppression, and the width of the conversion section of the transverse power division network and the vertical power division circuit can also be designed using the Taylor amplitude distribution.

Due to the accumulated phase deviation in the feeder caused by the frequency change, the main beam will be scanned away from the normal direction, and the position of the probe is the center position of the feed network of the radiating patch array 2, ensuring that the combined main beam with a larger beam width remains vertical on the array plane.

Further, the n-column microstrip line array is designed centrally symmetrically about the central metal through hole 5 to ensure that the maximum radiation point of the antenna is directly above the antenna, and each line of the microstrip line array adopts a cross-shaped power division network 4 to make the antenna gain less A frequency offset will occur.

Further, the metallized through hole 5 located in the center of the radiation patch array 2 is connected to the feeding network on the second dielectric substrate through probes. The input power is equally divided between the two identical half-arrays 10 of the entire radiating patch array 2 . Each half-array 10 comprises four sub-arrays 11 excited by parallel series feed networks. Each sub-array 11 in Figure 1 is fed in parallel to the modified sub-array with reversed patches, so that the radiation of the two parallel-fed sub-arrays is constructively superimposed in the broadside direction. For both types of sub-arrays, the main beam will scan away from the broadside direction due to the phase deviation accumulated in the feeder due to frequency variation. Each adjacent sub-array is a reversed patch to achieve radiation superposition, and the two types of sub-arrays are two reversed arrays. However, the two parallel-fed sub-arrays scan in opposite directions, and they have a combination of larger beamwidths while the main beam remains perpendicular to the array plane. The spacing between the sub-arrays fed in series is chosen to be about λ, a spacing that provides a suitable arrangement of the sub-arrays for the structure but is sufficient to avoid unnecessary additional feed losses. Therefore, in order to compensate for the phase difference between two consecutive sub-arrays fed along the series and to provide constitutive radiation on the broadside, the arrangement of adjacent sub-arrays should be changed.

To achieve the ideal radiation pattern, both the spacing between parallel-fed sub-arrays and the distance between two identical half-arrays should be optimized. After optimization, the total conductor area of the designed feed network is about 55440mm ² , which is half of the conductor area required by the traditional feed network of the microstrip array. Compared with the traditional serial-fed sub-array, the parallel serial-fed network proposed by the present invention can reduce the length of the transmission line by one time. And the size of the antenna can be significantly reduced. Therefore, array noise performance is improved due to reduced feed losses. The normalized radiation patterns at 16 GHz in the two principal planes (E-plane and H-plane) are shown in Figures 5 and 6. It can be seen from FIG. 5 and FIG. 6 that the peak gain of the radiation patch array of the present invention is 31.3dBi, the bandwidth is 800MHz, and the gain ripple is 1dB. The maximum directivity for an aperture of the same size as the proposed antenna array is about 32.9dBi. This means that the overall efficiency of the designed array is 69.6% and the overall loss is 1.6dB. It is further proved that the planar microstrip array antenna of the present invention has high efficiency and low loss.

In the description of the present invention, it should be understood that the terms "middle", "length", "upper", "lower", "front", "rear", "vertical", "horizontal", "inner", The orientation or positional relationship indicated by "outer", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that The device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

In the present invention, unless otherwise expressly stated and defined, a first feature "on" a second feature may be in direct contact with the first and second features, or in indirect contact with the first and second features through an intermediary. "Plurality" means at least two, eg, two, three, etc., unless expressly specifically limited otherwise.

In the present invention, unless otherwise expressly specified and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection , or integrated; it can be a mechanical connection or an electrical connection or can communicate with each other; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two components or the interaction relationship between the two components, unless otherwise expressly qualified. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

The above is only to illustrate the embodiments of the present invention, and not to limit the present invention. For those skilled in the art, all within the spirit and principle of the present invention, without any modification, equivalent replacement or improvement made by creative work etc., should be included within the protection scope of the present invention.

Claims (6)

1. A radiation patch array, characterized in that it is composed of n rows of radiation patch linear arrays; the radiation patch linear array is composed of m rows of radiation patch units; the radiation patch units include a cross-type power divider network and two rectangular patches; the cross-shaped power division network is a four-port structure, including an upper port, a lower port, a left port and a right port; the left port and the right two ports are respectively connected to a rectangular patch, so as to The rectangular patch is excited in the form of parallel connection; the upper port and the lower port are respectively connected in series to the upper port or the lower port of the adjacent cross-type power division network in the same column. 2 . The radiation patch array according to claim 1 , wherein the spacing between the radiation patch units is equal to the free space wavelength of 0.75 center frequency points, and the radiation patch unit adopts a magnetic boundary. 3 . Feed form. 3. A planar microstrip array antenna, comprising a first dielectric substrate, a metal floor, and a second dielectric substrate; the back of the first dielectric substrate is in contact with one surface of the metal floor, and the other surface of the metal floor The surface of the second dielectric substrate is in contact with one surface of the second dielectric substrate; it is characterized in that, the front surface of the first dielectric substrate is attached with the radiation patch array according to claim 1 or 2; The other side is provided with a feeding network; the center of the radiation patch array is provided with a metallized through hole; the metallized through hole penetrates the first dielectric substrate, the metal floor and the second dielectric substrate; the metal A probe is arranged in the through hole, and the probe is used to connect the radiation patch array and the feeding network. 4 . The planar microstrip array antenna according to claim 3 , wherein the feeding network adopts a cascade connection of multi-stage T-type microstrip power dividers to form a feeding structure of 1 divided by n channels. 5 . 5 . The planar microstrip array antenna according to claim 4 , wherein the feeding network is a series feeding network or a parallel feeding network. 6 . 6 . The planar microstrip array antenna according to claim 3 , wherein the input port of the feeding network adopts a standard SMA joint structure. 7 .

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