T-shaped receiving antenna array of three-coordinate radar
By using a T-shaped, non-centrally symmetrical array of five receiving antennas, the problems of low angle measurement accuracy and angle ambiguity in three-coordinate radar were solved, achieving higher angle measurement accuracy and fewer receiving channels.
Patent Information
- Application Number
- CN202520004219.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-01-02
AI Technical Summary
Existing three-coordinate radars have low angle measurement accuracy, and phase-based angle measurement has high requirements for antenna array layout design, which can easily lead to angle ambiguity.
A five-antenna array with a T-shaped non-centrally symmetrical structure is used, with three antennas in the horizontal direction for obtaining elevation information and three antennas in the vertical direction for obtaining azimuth information. The antenna spacing is less than half a wavelength, reducing the number of receiving channels.
It improves angle measurement accuracy, reduces angle measurement ambiguity, increases the total antenna length, and achieves higher angle measurement accuracy and fewer receiving channels.
Smart Images
Figure CN223729030U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the wireless electric detection technical field, especially is involved in T type receiving antenna array of three coordinate radar. BACKGROUND
[0002] Three coordinate radar needs to detect target position angle, and usually adopts phase method angle measurement, amplitude method angle measurement.
[0003] The amplitude method angle measurement commonly seen at present is to use the echo signal amplitude value received to measure angle, and the amplitude value change is determined by the antenna directional diagram and scanning mode, and the amplitude method angle measurement includes maximum signal method and difference method.The precision of maximum signal method is not high, and is generally 20% of the 3dB bandwidth of the antenna directional diagram.The precision of difference method is about 2% of the 3dB bandwidth of the antenna directional diagram, but the angle measurement system is relatively complex, needs to add difference network, and the equal signal axis direction is not the maximum value of the antenna directional diagram, so that the detection power is reduced by 20% than maximum signal method.The common phase method angle measurement is to use the phase difference value of the signal received by the antenna to measure angle, and the measurement precision is inversely proportional to the antenna spacing, that is, the greater the spacing, the higher the precision.At the same time, the spacing of the receiving antenna must be less than half a wavelength, otherwise the angle measurement will be angle ambiguous.Therefore, the phase method angle measurement has high requirements for the layout design of the antenna array.It is the technical problem to be solved by the utility model to design a new type of antenna array to cooperate with the phase method angle measurement to improve the angle measurement precision of three coordinate radar. CONTENT
[0004] The utility model aims at providing a new type of antenna array to improve the radar angle measurement precision by cooperating with the phase method angle measurement.
[0005] The utility model provides T type receiving antenna array of three coordinate radar, including five receiving antennas, it is respectively one antenna (1), two antennas (2), three antennas (3), four antennas (4) and five antennas (5), and the five receiving antennas are T type non-central symmetry structure;The T type non-central symmetry structure is by right to left in turn one antenna (1), two antennas (2) and three antennas (3) in horizontal direction;The T type non-central symmetry structure is by upper to lower in turn three antennas (3), four antennas (4) and five antennas (5) in vertical direction.
[0006] In some embodiments, the center distance of one antenna (1) and three antennas (3) in the horizontal direction is the first horizontal distance, and the center distance of two antennas (2) and three antennas (3) is the second horizontal distance;The difference between the first horizontal distance and the second horizontal distance is less than half a wavelength, and the wavelength is determined by the center frequency of the signal received by the receiving antenna.
[0007] In some embodiments, the center distance between antenna 3 (3) and antenna 4 (4) in the vertical direction is the first vertical distance, and the center distance between antenna 4 (4) and antenna 5 (5) is the second vertical distance; the difference between the first vertical distance and the second vertical distance is less than half a wavelength, and the wavelength is determined by the center frequency of the receiving antenna.
[0008] In some embodiments, the first horizontal distance is 437 mm.
[0009] In some embodiments, the second horizontal distance is 368 mm.
[0010] In some embodiments, the first vertical distance is 414 mm.
[0011] In some embodiments, the second vertical distance is 299 mm.
[0012] In some embodiments, antenna 1 (1) and antenna 2 (2) are target elevation information acquisition antennas; antenna 4 (4) and antenna 5 (5) are target azimuth information acquisition antennas; and antenna 3 (3) is a target elevation information and target azimuth information acquisition antenna.
[0013] The advantages of this invention are as follows: Compared with the prior art, this invention uses three receiving antennas in the horizontal direction to acquire target azimuth information and three receiving antennas in the vertical direction to acquire target elevation information. One receiving antenna is shared, forming a T-shaped structure, which reduces the number of receiving channels. The distance difference between the center positions of the antennas is less than half a wavelength, ensuring unambiguous angle measurement. The increased total length of the antennas improves angle measurement accuracy. In other words, this structure solves the problem of angle measurement ambiguity and accuracy conflict in phase-based angle measurement. Attached Figure Description
[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0015] Figure 1 This is a schematic diagram illustrating the specific principle of phase angle measurement in this embodiment of the present invention.
[0016] Figure 2 This is a schematic diagram of the layout of the T-shaped non-centrosymmetric antenna array in an embodiment of this utility model. Figure 1 . Detailed Implementation
[0017] In order to make the technical problems, technical solutions and beneficial effects of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application and not to limit the present application.
[0018] It should be noted that when an element is referred to as being "fixed" or "set" on another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or indirectly connected to the other element.
[0019] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0020] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.
[0021] Embodiments
[0022] In combination Figure 1 The T-shaped non-centrosymmetric antenna array structure provided by the present embodiment will now be described.
[0023] The present embodiment provides a T-shaped receiving antenna array, which is composed of five individual receiving antennas, namely a first antenna 1, a second antenna 2, a third antenna 3, a fourth antenna 4 and a fifth antenna 5.
[0024] The three receiving antennas in the horizontal direction, i.e. the first antenna 1, the second antenna 2 and the third antenna 3, are used to obtain target elevation information. The three receiving antennas in the vertical direction, i.e. the third antenna 3, the fourth antenna 4 and the fifth antenna 5, are used to obtain target azimuth information, wherein the third antenna 3 is a shared antenna, i.e. it is needed to obtain target azimuth information and also participate in obtaining target elevation information.
[0025] The distance between the center of the first antenna 1 and the third antenna 3 is 437 mm, and the distance between the center of the second antenna 2 and the third antenna 3 is 368 mm. The distance between the center of the third antenna 3 and the fourth antenna 4 is 414 mm, and the distance between the center of the fourth antenna 4 and the fifth antenna 5 is 299 mm. The minimum distance difference between the centers of the three horizontal receiving antennas is less than half a wavelength, and the distance between the center of the first antenna 1 and the center of the third antenna 3 is 69 mm, which is less than 150 mm. The minimum distance difference between the centers of the three vertical receiving antennas is less than half a wavelength, for example, the distance between the center of the third antenna 3 and the center of the fourth antenna 4 is 115 mm, which is less than 150 mm.
[0026] The specific principle of phase angle measurement is shown in FIG. 1. Figure 2 The radar is a narrowband array signal, and the straight line from the target to the two antennas is assumed to be parallel. Therefore, there is a distance difference between the target echo to the two antennas, and the distance difference is related to the incident angle:
[0027] ΔR = dsin(θ)
[0028] The phase difference can be obtained from the distance difference:
[0029]
[0030] Therefore, by measuring the phase difference of the two received signals, the incident angle of the target echo can be obtained.
[0031] The angle measurement error is:
[0032]
[0033] As shown in Table 1, the embodiment is a T-shaped receiving antenna array structure with a center frequency of 1.3 GHz.
[0034] Table 1 T-shaped receiving antenna array structure size of 1.3 GHz
[0035] Antenna No. Antenna No. Relative distance Antenna No. 1 Antenna No. 3 437 mm Antenna No. 3 Antenna No. 2 368 mm Antenna No. 3 Antenna No. 4 414 mm Antenna No. 4 Antenna No. 5 299 mm
[0036] That is, d 13 = 437 mm, d 32 = 368 mm, d 34 = 414 mm, and d 45 = 299 mm.
[0037] The half wavelength of the signal with a center frequency of 1.3 GHz is about 230 mm.
[0038] The distance difference Δd between the distance between the center positions of the first antenna 1 and the third antenna 3 and the distance between the center positions of the second antenna 2 and the third antenna 3 is used 12 = d 13 -d 32 = 69 mm, which is less than 230 mm, and no angle ambiguity occurs.
[0039] The distance difference Δd between the distance between the center positions of the third antenna 3 and the fourth antenna 4 and the distance between the center positions of the fourth antenna 4 and the fifth antenna 5 is used 35 = d 34 -d 45 = 115 mm, which is less than 230 mm, and no angle ambiguity occurs.
[0040] For the angle measurement accuracy, the baseline length in the elevation direction is D p = d 13 +d 32 = 805 mm, and the angle measurement error is
[0041]
[0042] The half-wavelength distance is improved by 7 times.
[0043] The baseline length in the azimuth direction is D a = d 34 +d 45 = 713 mm, and the angle measurement error is
[0044]
[0045] The half-wavelength distance is improved by 6.2 times.
[0046] Therefore, the structure can improve the angle measurement accuracy without angle ambiguity and reduce the number of receiving channels.
[0047] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims
1. A T-shaped receive antenna array for a three-dimensional radar, characterized in that Five receiving antennas are included, which are No. 1 antenna (1), No. 2 antenna (2), No. 3 antenna (3), No. 4 antenna (4) and No. 5 antenna (5), and the five receiving antennas are in a T-shaped non-central symmetric structure; the T-shaped non-central symmetric structure is horizontally arranged from right to left as No. 1 antenna (1), No. 2 antenna (2) and No. 3 antenna (3); the T-shaped non-central symmetric structure is vertically arranged from top to bottom as No. 3 antenna (3), No. 4 antenna (4) and No. 5 antenna (5).
2. A T-shaped receive antenna array for a three-dimensional radar according to claim 1, characterized in that The center distance between No. 1 antenna (1) and No. 3 antenna (3) in the horizontal direction is a first horizontal distance, and the center distance between No. 2 antenna (2) and No. 3 antenna (3) is a second horizontal distance; the difference between the first horizontal distance and the second horizontal distance is less than one-half wavelength, and the wavelength is determined by the center frequency of the signal received by the receiving antenna.
3. A T-shaped receive antenna array for a three-dimensional radar according to claim 2, characterized in that The center distance between No. 3 antenna (3) and No. 4 antenna (4) in the vertical direction is a first vertical distance, and the center distance between No. 4 antenna (4) and No. 5 antenna (5) is a second vertical distance; the difference between the first vertical distance and the second vertical distance is less than one-half wavelength, and the wavelength is determined by the center frequency of the receiving antenna.
4. A T-shaped receive antenna array for a three-dimensional radar according to claim 3, characterized in that The first horizontal distance is 437 mm.
5. A T-shaped receive antenna array for a three-dimensional radar according to claim 4, wherein The second horizontal distance is 368 mm.
6. A T-shaped receive antenna array for a three-dimensional radar according to claim 5, characterized in that The first vertical distance is 414 mm.
7. A T-shaped receive antenna array for a three-dimensional radar according to claim 6, characterized in that The second vertical distance is 299 mm.
8. A T-shaped receive antenna array for a three-dimensional radar according to claim 7, characterized in that No. 1 antenna (1) and No. 2 antenna (2) are target elevation information acquisition antennas; No. 4 antenna (4) and No. 5 antenna (5) are target azimuth information acquisition antennas; and No. 3 antenna (3) is a target elevation information and target azimuth information acquisition antenna.