A ground target positioning test device

Abstract

The present invention relates to a ground target positioning test device, including a transmitting antenna and a receiving antenna, wherein the transmitting antenna is a wide bandwidth beam antenna, the receiving antenna is a wideband narrow beam array antenna, the operating frequency of the transmitting antenna is 2.5-4GHz, the beam width is greater than 90°, and the beam angle of the receiving antenna is less than 10°; the wide bandwidth beam antenna is a planar gradient slot Vivaldi antenna, and the wideband narrow beam array antenna is composed of eight planar gradient slot Vivaldi antennas arranged as array elements. The present invention increases the beam width of the transmitting antenna, reduces the beam width of the receiving antenna, and meets the miniaturization requirements, can be used for high-power transmission and long-distance target detection, and improves the accuracy of target positioning.

Description

Technical Field

[0001] The invention relates to the technical field of antenna design, in particular to a ground target positioning test device. Background Art

[0002] The Vivaldi antenna, also known as the tapered slot antenna (TSA), is an ideal antenna for broadband applications. It has a simple structure, is easy to manufacture, and has a high gain. When designing a narrowband antenna, it is relatively easy to achieve a relatively stable standing wave ratio and gain effect within its operating bandwidth. However, ultra-wideband antennas have the characteristics of extremely wide operating frequency bandwidth, and it is not easy to ensure that the corresponding performance parameters within the operating frequency band meet the index requirements. In addition, due to the increasing requirements for the convenience of target detection testing, it is of practical value to integrate the designed antenna into a portable system to further reduce the size and weight of the test system. When designing an ultra-wideband antenna, consider using a pulse signal as an excitation, so it is necessary to develop a suitable antenna that meets the design requirements within a wide bandwidth and meets the requirements of miniaturization. Summary of the invention

[0003] In view of the deficiencies of the prior art, the present invention provides a ground target positioning test device, the purpose of which is to increase the beam width of a transmitting antenna, reduce the beam width of a receiving antenna and meet miniaturization requirements, thereby improving the accuracy of target positioning.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A ground target positioning test device comprises a transmitting antenna and a receiving antenna, wherein the transmitting antenna is a wide bandwidth beam antenna, the receiving antenna is a wideband narrow beam array antenna, the operating frequency of the transmitting antenna is 2.5-4 GHz, the beam width is greater than 90°, and the beam angle of the receiving antenna is less than 10°;

[0006] The wide bandwidth beam antenna is a planar tapered slot Vivaldi antenna, comprising a first microstrip-slotline feeding portion, a first antenna slot tapered portion, and a first metal slot portion;

[0007] The first microstrip-slotline feeding part, the feeder end of which is butt-jointed with an elliptical resonant cavity and a first rectangular transition slot, the major axis length of the elliptical resonant cavity is 14-32 mm, the minor axis length is 6-12 mm, and the length of the first rectangular transition slot is 22.8-23 mm;

[0008] The width of the slot line at the end of the gradient portion of the first antenna slot is 48-50 mm, and the width at the starting end is 2 mm;

[0009] The first metal slotted portion comprises a plurality of slots symmetrically arranged on both sides of the end of the first antenna slot gradient portion, and the slot lengths are all equal;

[0010] The broadband narrow beam array antenna is composed of eight planar tapered slot Vivaldi antennas arranged as array elements, and the structure of the array element includes a second microstrip-slotline feeding part, a second antenna slot tapered part, a second metal slot part and a director:

[0011] The second metal slotted portion includes a plurality of slots symmetrically arranged on both sides of the end of the second antenna slot gradient portion, the lengths of the slots decrease from the beginning to the end, and the lengths of the last few slots are kept equal.

[0012] Further technical solutions are:

[0013] The slots of the second metal slotted part are right-angled triangular slots, wherein the slot length at the head end is 23mm, the slot length at the end is 8mm, the slot length of the last few equal-length slots is 5mm, the slot width is 1.5mm, and the distance between the last slot and the top of the antenna is 7-7.5mm.

[0014] The slots of the second metal slotted portion are rectangular slots, the slot lengths are in an arithmetic progression, and adjacent slots along the main beam direction are distributed at equal intervals.

[0015] The width of the slot line end of the second antenna slot gradient part is the same as the array element width, which is 55 mm, and the array element length is 82 mm;

[0016] The feeder end of the second microstrip-slotline feeding part is connected to a circular resonant cavity, the radius of the circular resonant cavity is 6 mm, and the distance between the center of the circle and the bottom of the antenna is 8-9 mm;

[0017] The structure of the director is an equilateral triangle slot, and the ratio of the height to the base of the triangle is 2.

[0018] The broadband narrow beam array antenna is fed by a power divider, and each level of power divider is distributed in a symmetrical structure, and the microstrip line width of each level of power divider is 1 mm.

[0019] The receiving antenna is assembled on a turntable which can rotate 360 ​​degrees through positioning holes arranged at intervals.

[0020] The groove of the first metal slotted part is a rectangular groove with a width of 2 mm and a length of 16-20 mm. The first rectangular groove is 10-11 mm away from the end of the antenna, and the distance between adjacent rectangular grooves is 2-3 mm.

[0021] The length and width of the transmitting antenna are both 150 mm; the sizes of the longitudinal feed line and the transverse feed line of the first microstrip-slotline feeding part are 18.8 mm and 47.9 mm respectively, and the fan-shaped radius at the end of the feed line is 8 mm.

[0022] The beneficial effects of the present invention are as follows:

[0023] The operating frequency bands of the transmitting and receiving antennas of the present invention are both 2.5GHz to 4GHz. The half-power beam width of the transmitting antenna is greater than 90°, and the half-power beam width of the receiving antenna is less than 10°. The beam of the transmitting antenna needs to be able to cover a wider spatial angle to ensure that the target to be measured can receive and reflect the signal radiated by the transmitting antenna. The transmitting antenna needs to have good impedance matching characteristics and gain characteristics to achieve long-distance detection. The receiving antenna has the advantages of miniaturization, ultra-wideband, narrow beam, and good directivity. The transmitting antenna is used to illuminate the space, and the receiving antenna captures the signal reflected by the target to be measured through angle scanning to find the target and determine the target angle. Then, based on the positional relationship between the transmitting and receiving antennas and the signal transmission and reception time, combined with the signal time-frequency domain measurement results, it is possible to quickly and accurately determine the angle of the target and accurately calculate the position of the target. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of the transmitting antenna base plate of the present invention.

[0025] Figure 2 It is a schematic diagram of the first microstrip-slotline feeding part of the transmitting antenna of the present invention.

[0026] Figure 3 This is a performance diagram of the transmitting antenna standing wave ratio of the present invention.

[0027] Figure 4 This is a reflection parameter diagram of the transmitting antenna of the present invention.

[0028] Figure 5 It is the E-plane radiation pattern of the transmitting antenna of the present invention in the range of 2.5 GHz-4 GHz.

[0029] Figure 6 The three-dimensional radiation pattern and H-plane radiation pattern of the transmitting antenna of the present invention at 2.5 GHz.

[0030] Figure 7 It is a structural diagram of an array element of a receiving antenna of the present invention.

[0031] Figure 8 It is the element antenna return loss of the receiving antenna of the present invention.

[0032] Fig. 9 It is the E-plane radiation pattern of the array element antenna of the receiving antenna of the present invention.

[0033] Fig.10 It is the standing wave ratio diagram of the receiving antenna of the present invention.

[0034] Fig.11 It is a schematic diagram of a model of a receiving antenna of the present invention.

[0035] Fig.12 The E-plane radiation patterns of the receiving antenna of the present invention are simulated and measured at 2 GHz, 3 GHz and 4 GHz.

[0036] Fig.13 It is the three-dimensional radiation pattern of the receiving antenna of the present invention at 4 GHz.

[0037] Fig.14 It is a test principle diagram of the present invention.

[0038] Fig.15 It is the TDT test result of the present invention.

[0039] Fig.16 It is the actual and test location diagram of the test target of the present invention. DETAILED DESCRIPTION

[0040] The specific implementation of the present invention is described below with reference to the accompanying drawings.

[0041] like Figure 1 and Figure 2 As shown, the ground target positioning test device of this embodiment includes a transmitting antenna and a receiving antenna, the transmitting antenna is a wide bandwidth beam antenna, the receiving antenna is a wideband narrow beam array antenna, the operating frequency of the transmitting antenna is 2.5-4GHz, the beam width is greater than 90°, and the beam angle of the receiving antenna is less than 10°;

[0042] like Figure 1-Figure 3 As shown, the wide bandwidth beam antenna is a planar tapered slot Vivaldi antenna, comprising a first microstrip-slotline feeding portion, a first antenna slot tapered portion, and a first metal slot portion;

[0043] The first microstrip-slotline feeding part, the feeder end of which is butt-jointed with the elliptical resonant cavity and the first rectangular transition slot, the major axis length of the elliptical resonant cavity is 14-32 mm, the minor axis length is 6-12 mm, and the length of the first rectangular transition slot is 22.8-23 mm;

[0044] The width of the slot line at the end of the gradient portion of the first antenna slot is 48-50 mm, and the width at the starting end is 2 mm;

[0045] The first metal slotted portion includes a plurality of slots symmetrically arranged on both sides of the end of the first antenna slot gradient portion, and the slots have the same length;

[0046] Specifically, the groove of the first metal slotted portion is a rectangular groove with a width of 2 mm and a length of 16-20 mm. The first rectangular groove is 10-11 mm away from the end of the antenna, and the distance between adjacent rectangular grooves is 2-3 mm.

[0047] Specifically, the length and width of the transmitting antenna are both 150 mm; the sizes of the longitudinal feed line and the transverse feed line of the first microstrip-slotline feeding part are 18.8 mm and 47.9 mm respectively, and the fan-shaped radius of the feed line end is 8.

[0048] Generally speaking, for a planar slot tapered antenna, the narrow opening of the slot line corresponds to the radiation of a high-frequency short-wavelength signal, and the wide opening corresponds to the radiation of a low-frequency long-wavelength signal. Considering that the antenna is designed for an operating frequency of 2.5-4 GHz, the optimal parameters are selected as shown in Table 1 below.

[0049] Table 1 Preferred parameters of transmitting antenna (mm)

[0050] XD Y l w h X R w1 wh l1 w3 l3 l4 h2 w2 w3 32 12 150 150 20 29.4 8 1.2 1 46.7 48 22.8 112.5 20 2 48

[0051] Combination Figure 1 and Figure 2 The meanings of the parameter symbols in Table 1 are as follows:

[0052] W: antenna width; 1: antenna length; w3: maximum width of antenna gradient slot; 14: longitudinal length of antenna gradient slot; l3: length of antenna rectangular transition slot; Xd: short semi-axis of elliptical resonant cavity; Yd: long semi-axis of elliptical resonant cavity; wh: width of antenna rectangular transition slot; X: distance between feeder and right side; h: longitudinal length of feeder; l1: transverse length of feeder; w1: width of feeder; R: fan-shaped radius at the end of feeder;

[0053] In the range of 1.5GHz to 4GHz, the simulation results of the standing wave ratio are as follows Figure 3 As shown, the antenna reflection coefficient is Figure 4 The results show that the standing wave ratio in the working frequency band is less than 2.2, which means that the impedance matching performance of the antenna is good.

[0054] The final model of the designed Vivaldi ultra-wideband antenna is simulated and measured to obtain its E-plane radiation pattern as shown in the figure. Figure 5 , the three-dimensional far-field radiation pattern and H-plane gain radiation pattern of the 2.5GHz antenna are as follows Figure 6 .Depend on Figure 5 As shown in the figure, after the optimization of the Vivaldi antenna, the beam conditions in each frequency band are improved, and the beam width can reach 125.5° in 3G.

[0055] from Figure 5 It can be seen from the measured radiation patterns of the single transmitting antenna at 2.5GHz, 3GHz, 3.5GHz and 4GHz that the beamwidths are 108.8°, 122°, 109° and 90° respectively, all of which are greater than 90° and meet the design requirements.

[0056] The broadband narrow beam array antenna is composed of eight planar tapered slot Vivaldi antennas arranged as array elements. Figure 7 As shown, the structure of the array element includes a second microstrip-slot line feeding part, a second antenna slot gradient part, a second metal slot part and a director;

[0057] The second metal slotted portion includes a plurality of slots symmetrically arranged on both sides of the end of the second antenna slot gradient portion, the lengths of the slots decrease from the beginning to the end, and the lengths of the last few slots are kept equal.

[0058] Preferably, the slot length decreases in an arithmetic gradient.

[0059] As an implementation mode, the slot of the second metal slotted portion is a right-angled triangle slot, wherein the slot length at the head end is 23 mm, the slot length at the end is 8 mm, the slot length of the last few equal-length slots is 5 mm, the slot width is 1.5 mm, and the distance between the last slot and the top of the antenna is 7-7.5 mm.

[0060] Metal slots can make the area where the surface current flows diffuse outward, and the slots can radiate some energy. The slotted antenna can improve the gain of the antenna, and in this process, the rectangular slot theoretically has no obvious effect on the attenuation of the end-fire direction to the surroundings. On the contrary, part of the enriched energy may come from the narrower opening. Therefore, if the rectangular slots are properly slotted, the position and width are obtained, the energy that would have collapsed backwards can be enriched in the end-fire direction, making the radiation angle larger. And through simulation, different distances between slots have different effects on the beam width. The simulation results show that the energy at the end of the antenna is more enriched at the location where the slots are densely populated, which has a significant impact on the antenna.

[0061] On the basis of equidistant gradient slotting, three slots of equal length are maintained near the die forging position of the antenna, which can achieve better results without affecting other electrical properties of the antenna.

[0062] As another embodiment, the grooves of the second metal grooved portion are rectangular grooves, adjacent grooves are equally spaced, the groove lengths are in an arithmetic progression, and the length difference between two adjacent rectangular grooves is 3 mm.

[0063] As a specific implementation, the second microstrip-slotline feeding part has a feeder end connected to a circular resonant cavity, the radius of the circular resonant cavity is 6 mm, and the distance between the center of the circle and the bottom of the antenna is 8-9 mm;

[0064] As a specific implementation, the structure of the director is an equilateral triangle groove, and the ratio of the height to the base of the triangle is 2.

[0065] The triangular director can also increase the gain of the antenna and reduce the beam width of the antenna. After CST modeling and multiple simulation analyses of various parameters, the triangular slot size on the patch is 8mm high and 4mm wide for better results;

[0066] As a specific implementation, the width of the slot line end of the second antenna slot gradient part is the same as the array element width, which is 55 mm, and the array element length is 82 mm.

[0067] Based on the simulation structure of each parameter, the optimal parameter combination is determined as shown in Table 2.

[0068] Table 2 Optimal parameters of receiving antenna elements (mm)

[0069]

[0070] Combined with Figure 7 , the meaning of each parameter in Table 2 is:

[0071] W: receiving antenna element width; L: receiving antenna element length; d1: distance between the center and the bottom of the circular resonant cavity; R: radius of the circular resonant cavity; l3: length of the starting slot; l2: length of the middle slot; l1: length of the end slot; d2: distance between the end slot and the top; d3: width of the end slot; d4: distance between the right-angle sides; C1: horizontal length of the feeder; C2: longitudinal length of the feeder; w: width of the feeder; d5: distance between the feeder and the right side; R1: radius of the feeder end; a: width of the triangular director; b: height of the triangular director.

[0072] The simulated return loss result of the receiving antenna is as follows: Figure 8 As shown in the figure. The results show that the resonance point of the antenna is at 4.085GHz, and the gain of the antenna is 7.1dBi at this frequency. In the range of 2GHz to 6GHz, the S parameter is basically below -10dB, and the loss of the antenna is small. The far-field E-plane radiation pattern of the simulated antenna at 2GHz, 3GHz and 4GHz is shown in the figure. Fig. 9 As shown in the figure, the antenna beam widths are 65.9°, 65.2° and 59.4°, all less than 70°. , and the antenna gain is greater than 4dBi in the range of 2GHz to 6GHz.

[0073] The standing wave ratio of the simulated antenna is as follows: Fig.10 As shown. The standing wave ratio of the antenna is related to the antenna width. When the antenna units are arrayed, the array spacing will limit the size of the unit width. As can be seen from the figure, in the 2GHz to 6GHz frequency band, the antenna width is 55mm, and the maximum standing wave ratio appears at the 2.82GHz frequency point, which is 2.65.

[0074] In order to further enhance the directional radiation capability of the antenna and achieve the requirement of beam width less than 10°, the Vivaldi antenna with improved beam width is arranged into an 8-element antenna array in a certain way. The receiving antenna is assembled on a turntable that can rotate 360° through the positioning holes arranged at intervals.

[0075] Since the test instrument is a network analyzer with fewer ports, a power divider is used to feed the antenna array. Fig.11 The parameters are shown in Table 3.

[0076] Table 3 Main parameters of antenna array (mm)

[0077]

[0078] Combination Fig.11 , the meanings of the parameters in Table 3 are:

[0079] L: length of the antenna array; W: width of the antenna array; L1: distance between the last power divider and the left side of the array; L2: distance between the P1 and P3 positioning holes; L3: distance between the P3 positioning hole and the right side of the array; D1: length of the second power divider line; D3: distance between the P3 positioning hole and the bottom of the array.

[0080] Each power divider has a symmetrical structure. The microstrip line width of each power divider is 1mm. There are three positioning points, namely P1 (10, -70, 1.635), P2 (192.5, -70, 1.635), and P3 (395, -70, 1.635). Holes with an inner diameter of 6mm are drilled at the three positioning points so that the antenna array can be assembled on the turntable bracket.

[0081] The final model of the designed narrow beam 8-element array antenna is simulated and measured to obtain the E-surface radiation pattern of the antenna at different frequencies. Fig.12 , 4GHz three-dimensional radiation pattern as follows Fig.13 The measured beam widths of the receiving antenna array at 2GHz, 3GHz, and 4GHz frequencies are 9.8°, 7°, and 4°, respectively, which meet the design requirements.

[0082] In the ground target positioning test device of this embodiment, the transmitting antenna in the test is the designed wide bandwidth beam antenna, and the receiving antenna uses a broadband narrow beam 8-element array, which is placed on a rotating table with adjustable angle. The turntable can also use an electric turntable, which is connected to the computer through a controller and a driver to control the angle.

[0083] The test principle diagram is as follows Fig.14As shown, the distance between the two antennas is fixed. During the test, the transmitting and receiving antennas are connected to ports 1 and 2 of the E5071C vector network analyzer respectively, forming a system for positioning together, and measuring the distance w between the two antennas. The vector network analyzer transmits electromagnetic wave signals to space through port 1 via the transmitting antenna. The beam width of the receiving antenna is small. It is placed on a rotating table and connected to port 2 of the vector network analyzer. The angle of the rotating table is adjusted to search for signals around. Observe the S21 parameter of the vector network. When S21 reaches the maximum value, that is, the main beam of the receiving antenna points to the reflector, record the angle of the rotating table θ at this time, which is the azimuth angle θ of the reflector. Then keep the angle of the receiving antenna unchanged, adjust the vector network analyzer to the TDT parameter, measure the time difference T from the moment the transmitting antenna sends a signal to the moment the receiving antenna receives the signal, and the corresponding distance and, then the position of the target to be measured can be obtained. Before the test, first calibrate the transmitting port PORT1 and the receiving port PORT2 after the vector network analyzer is connected to the cable, so that the reference positions of the signal transmission and reception are both located at the ports of the antenna. Then connect the transmitting and receiving antennas to the vector network analyzer at the same time. Point the main direction of the transmitting antenna to the side where the target is located, and point the main direction of the receiving antenna to the vertical direction of the line connecting the transmitting and receiving antennas. Observe the S21 parameter of the vector network analyzer, rotate the rotating table and record the angle θ corresponding to the maximum S21. The actual measurement obtained during the test was 4.2m and the angle θ was 6°. Then use the E5071C vector network time domain TDT to measure the sum of the distance from the transmitting antenna to the object under test and the distance between the object under test and the receiving antenna, L1+L2, and finally the coordinate point of the object under test can be solved.

[0084] The test distance is about 30 meters. Fig.15 , analyzing the TDT test results, it can be obtained that when the peak point 1 (corresponding to mark1) is 17.65ns-5.295m, the two antennas are directly coupled, and the signal obtained by the receiving antenna; when the peak point 2 (for Mark2) is 202.3ns-60.69m, it is the data captured by the receiving antenna after the signal is reflected by the object. The actual distance measured by the laser rangefinder: the measured target is 30.31m away from the transmitting antenna and 30.2m away from the receiving antenna. Therefore, the actual L1+L2=60.51m. Considering that the actual distance of the antenna is 4.2m, and the test distance is 5.295m, the distance difference is 1.095m, which is determined by the difference between the cable port and the electromagnetic wave feed port. Therefore, the tested L1+L2=59.6m.

[0085] The actual and tested positions of the target are shown in Figure 2. Fig.16As shown. The two square points at the bottom are the transmitting antenna and the receiving antenna. (3.278, 30.13) is the measured target point, and (3.138, 29.86) is the estimated result point of the test. From the results, it can be seen that the error of the x and y coordinate values ​​of the test results is less than 0.3m, and the distance of the test object is about 30 meters, which meets the requirements of practical applications.

[0086] The working frequency bands of the transmitting and receiving antennas determined by the present invention are both 2.5GHz to 4GHz. The half-power beam width of the transmitting antenna is greater than 90°, and the half-power beam width of the receiving antenna is less than 10°. The beam of the transmitting antenna needs to be able to cover a wider spatial angle to ensure that the target to be measured can receive and reflect the signal radiated by the transmitting antenna. The transmitting antenna needs to have good impedance matching characteristics and gain characteristics to achieve long-distance detection. The beam of the receiving antenna is narrow and has good directivity. The transmitting antenna is used to illuminate the space, and the receiving antenna captures the signal reflected by the target to be measured through angle scanning to find the target and determine the target angle. Then, based on the positional relationship between the transmitting and receiving antennas and the signal transmission and reception time, combined with the signal time-frequency domain measurement results, the target angle can be quickly and accurately determined and the target position can be accurately calculated.

Claims

1. A ground target positioning test device, characterized in that: It includes a transmitting antenna and a receiving antenna, wherein the transmitting antenna is a wide bandwidth beam antenna, the receiving antenna is a wideband narrow beam array antenna, the operating frequency of the transmitting antenna is 2.5-4GHz, the beam width is greater than 90°, and the beam angle of the receiving antenna is less than 10°; The wide bandwidth beam antenna is a planar tapered slot Vivaldi antenna, comprising a first microstrip-slotline feeding portion, a first antenna slot tapered portion, and a first metal slot portion; The first microstrip-slotline feeding part, the feeder end of which is butt-jointed with an elliptical resonant cavity and a first rectangular transition slot, the major axis length of the elliptical resonant cavity is 14-32 mm, the minor axis length is 6-12 mm, and the length of the first rectangular transition slot is 22.8-23 mm; The width of the slot line at the end of the gradient portion of the first antenna slot is 48-50 mm, and the width at the starting end is 2 mm; The first metal slotted portion comprises a plurality of slots symmetrically arranged on both sides of the end of the first antenna slot gradient portion, and the slot lengths are all equal; The broadband narrow beam array antenna is composed of eight planar tapered slot Vivaldi antennas arranged as array elements, and the structure of the array element includes a second microstrip-slotline feeding part, a second antenna slot tapered part, a second metal slot part and a director; The second metal slotted portion includes a plurality of slots symmetrically arranged on both sides of the end of the second antenna slot gradient portion; the number of slots on each side is 10, the slot lengths decrease from the beginning to the end, and the four slots at the end are kept equal in length.

2. The ground target positioning test device according to claim 1, characterized in that: The slots of the second metal slotted part are right-angled triangular slots, wherein the slot length at the head end is 23mm, the slot length at the end is 8mm, the slot length of the last few equal-length slots is 5mm, the slot width is 1.5mm, and the distance between the last slot and the top of the antenna is 7-7.5mm.

3. The ground target positioning test device according to claim 2, characterized in that: The slots of the second metal slotted portion are rectangular slots, the slot lengths are in an arithmetic progression, and adjacent slots along the main beam direction are distributed at equal intervals.

4. The ground target positioning test device according to claim 1, characterized in that: The width of the slot line end of the second antenna slot gradient part is the same as the array element width, which is 55 mm, and the array element length is 82 mm; The feeder end of the second microstrip-slotline feeding part is connected to a circular resonant cavity, the radius of the circular resonant cavity is 6 mm, and the distance between the center of the circle and the bottom of the antenna is 8-9 mm; The structure of the director is an equilateral triangle, and the ratio of the height to the base of the equilateral triangle is 2.

5. The ground target positioning test device according to claim 1, characterized in that: The broadband narrow beam array antenna is fed by a power divider, and each level of power divider is distributed in a symmetrical structure, and the microstrip line width of each level of power divider is 1 mm.

6. The ground target positioning test device according to claim 1, characterized in that: The receiving antenna is assembled on a turntable which can rotate 360 ​​degrees through positioning holes arranged at intervals.

7. The ground target positioning test device according to claim 1, characterized in that: The groove of the first metal slotted part is a rectangular groove with a width of 2 mm and a length of 16-20 mm. The first rectangular groove is 10-11 mm away from the end of the antenna, and the distance between adjacent rectangular grooves is 2-3 mm.

8. The ground target positioning test device according to claim 1, characterized in that: The length and width of the transmitting antenna are both 150 mm; the sizes of the longitudinal feed line and the transverse feed line of the first microstrip-slotline feeding part are 18.8 mm and 47.9 mm respectively, and the fan-shaped radius at the end of the feed line is 8 mm.

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