Amplitude comparison direction finding method and system

Abstract

The invention relates to the technical field of electronics, and discloses an amplitude comparison direction finding method and system, and the method comprises the steps: forming a matching template based on the amplitude of a direction finding channel, comparing a measurable template of a new signal with a storage template, and determining the direction of arrival of the new signal. According to the invention, the problem that the requirement for receiving channel resources is large in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the field of electronic technology, and specifically to a method and system for amplitude comparison direction finding. Background Art

[0002] The amplitude comparison direction finding system is widely used in the field of radio direction finding due to its advantages such as simple structure, stable performance, and fast direction finding speed. Its basic principle is to measure the amplitudes of multiple antennas, and combine the antenna pattern and the amplitude difference between adjacent antennas to complete the azimuth measurement. The currently widely used amplitude comparison direction finding system is four-amplitude comparison direction finding.

[0003] The current technology has the following limitations: the number of amplitude extraction channels is the same as the number of amplitude comparison antennas, which requires a large amount of receiving channel resources and high costs. Summary of the Invention

[0004] To overcome the deficiencies of the prior art, the present invention provides a method and system for amplitude comparison direction finding, which solves the problems existing in the prior art such as large demand for receiving channel resources.

[0005] The technical solution adopted by the present invention to solve the above problems is as follows:

[0006] A method for amplitude comparison direction finding, which forms a matching template based on the amplitudes of the direction finding channels, compares the measurable template of the new signal with the stored template, and determines the direction of arrival of the new signal.

[0007] As a preferred technical solution, the number of direction finding channels is M; where M≥2 and M is an integer.

[0008] As a preferred technical solution, it includes the following steps:

[0009] S1, combining the signals transmitted by N antennas to generate M combined signals, and extracting the amplitudes of the M combined signals; where N≥2 and N is an integer;

[0010] S2, generating a template vector through linear combination of the amplitudes of the M combined signals, and storing the theoretical template vectors of all angles of arrival;

[0011] S3, when a new signal is incident on the N antennas, comparing the measurable template of the new signal with the stored template to determine the direction of arrival of the new signal.

[0012] As a preferred technical solution, the angle corresponding to the minimum mean square error is selected as the direction of arrival of the signal.

[0013] As a preferred technical solution, the N antennas can be set with attenuation, and if attenuation is set, the attenuation amount can be adjusted.

[0014] As a preferred technical solution, the attenuation amount is adjusted by a prior exhaustive search method.

[0015] As a preferred technical solution, the attenuation is 10 dB.

[0016] As a preferred technical solution, N = 4 and M = 3.

[0017] As a preferred technical solution, the four antennas are respectively arranged in the directions of 0°, 90°, 180° and 270°, and the four antennas divide the 360° direction finding range into 8 sub-regions.

[0018] A ratio amplitude direction finding system for implementing the described ratio amplitude direction finding method includes an antenna, a ratio amplitude front end, an amplitude extraction branch, and a ratio amplitude direction finding module that are communicatively connected in sequence; wherein, the ratio amplitude front end is used to combine the signals transmitted by the antenna to generate a combined signal, the amplitude extraction branch is used to extract the amplitude value of the combined signal, and the ratio amplitude direction finding module is used to compare the measurable template of the new signal with the stored template to determine the direction of arrival of the new signal.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) By reducing the amplitude extraction channels, the present invention reduces the resources and costs of the ratio amplitude direction finding system;

[0021] (2) The present invention has the advantages of low resource consumption and low cost, and is particularly suitable for systems with small position space and few resource configurations;

[0022] (3) The present invention meets the requirements of low resource consumption, easy operability, volume, weight, etc. in electronic systems. The hardware of this circuit technology has little modification, which is convenient for being equipped into existing equipment and field upgrading. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a principle block diagram (four-ratio amplitude system) of the ratio amplitude direction finding method described in the present invention;

[0024] Figure 2 It is a structural schematic diagram of the ratio amplitude direction finding system described in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following will further describe the present invention in detail in conjunction with the embodiments and the drawings, but the embodiments of the present invention are not limited thereto.

[0026] Embodiment 1

[0027] Such as Figures 1 to 2As shown in the figure, the present invention aims to solve the problem of high receiving channel resources in the amplitude comparison direction finding system in the field of radio direction finding. By designing a low-cost amplitude comparison direction finding system, the resource consumption of the amplitude comparison direction finding system is reduced and the cost is lowered, thus solving the problem of high receiving channel resources. Different from the traditional direct direction finding, the present invention reduces the number of amplitude extraction channels, and indirectly measures the angle of the incoming signal by designing different matching templates and adopting the method of template matching. This method has the advantages of low cost and low resource consumption, and the technical principles and implementation of each link are simple, which is convenient for being equipped on existing equipment.

[0028] This embodiment proposes a design method for a low-cost amplitude comparison direction finding system. The core idea of this method is to form a matching template based on the amplitudes of the main direction finding channel 1 (PX), main channel 2 (PY), and auxiliary channel (PF), and identify the incoming wave angle through the template matching method. The working principle is shown in Figure 1 the figure.

[0029] Taking the four-amplitude system as an example, 4 antennas are respectively arranged in the directions of 0°, 90°, 180°, and 270°. The 360° direction finding range is divided into 8 sub-regions. 10 dB attenuation amounts are indicated at the positions of antenna 2 and antenna 3. The attenuation amounts of the receiving channels of antenna 2 and antenna 3 are equivalent to the front end of the antenna (the signal combining is placed after this antenna). The 4-way antenna combination generates 3 combined signals and enters the amplitude extraction branch. The amplitude extraction branch detects and extracts the amplitudes PX i , PY i , PF i of these 3 signals, and then generates a template vector through the linear combination of these amplitudes:

[0030] [g1(PX i ), g2(PY i ), g3(PF i )]

[0031] And store the theoretical template vectors of all incoming wave angles:

[0032]

[0033] Among them, i represents the current angle index value, and the measurement range of 360° is divided into N direction finding sub-intervals.

[0034] When a new signal is incident on this antenna array, the measurement template vector can be obtained in the above way of extracting the theoretical template vector as:

[0035]

[0036] Compare this measurement template vector with the stored template vector (i.e., the theoretical template vector), and select the angle with the minimum mean square error as the signal incoming wave direction, that is:

[0037]

[0038] As can be seen from the three-amplitude-ratio direction-finding algorithm, such antenna layout, link design, etc. introduce new dimensional information. The key design points lie in antenna attenuation configuration, PX / PY / PF channel design, and template vector design, which are specifically described as follows.

[0039] a) Antenna attenuation configuration

[0040] For the four antennas in the layout, the attenuation amount of each antenna can be configured as [L1,..,L4]. Whether there is an attenuation amount and how much the attenuation amount is can be configured and selected. The best attenuation amount configuration can be ensured through prior exhaustive search.

[0041] b) PX / PY / PF channel design

[0042] PX / PY / PF is generated from the combined signals of the four antennas. Appropriate antenna combinations can be selected for combining. The antenna combinations can be divided according to the actual zoning and antenna characteristics. It is recommended that the combination methods be PX = L1 * antenna 1 + L3 * antenna 3, PY = L2 * antenna 2 + L4 * antenna 4, and PF = L3 * antenna 3 + L4 * antenna 4.

[0043] c) Template vector design

[0044] The purpose of template vector design is to find the distinguishable dimensional information of the amplitudes measured by PX / PY / PF. Any template vector that can distinguish different angles can be used. The template vectors designed in this embodiment are respectively:

[0045] g1 = PX, g2 = PY, g3 = PF

[0046] Compared with the traditional amplitude-ratio direction-finding system design, the present invention reduces the amplitude extraction channels, thereby reducing the resources and costs of the amplitude-ratio direction-finding system. The present invention has the advantages of less resource consumption and low cost, and is particularly suitable for systems with small position space and few resource configurations. The present invention meets the requirements of less resource consumption, easy operation, volume, weight, etc. in electronic systems. The technical principles and implementations of each link of the invention are simple and convenient to be equipped into existing equipment.

[0047] Embodiment 2

[0048] As Figures 1 to 2 shown, on the basis of Embodiment 1, the present invention provides a more refined implementation manner.

[0049] Based on the principle of the low-cost amplitude-ratio direction-finding system proposed by the present invention, a verification system is built as shown in Figure 2 .

[0050] a) The operating frequency band range of the system is 2 GHz to 18 GHz. The antenna, the amplitude comparison front end, and the amplitude comparison extraction branch are all required to have an operating frequency range covering 2 GHz to 18 GHz. The amplitude comparison direction finding PX / PY / PF extracts the angle of the incoming wave signal by amplitude.

[0051] b) The direction finding results for various input signal powers within the frequency range of 2 GHz to 18 GHz were measured. Some of the results are listed in Table 1. The low-cost amplitude comparison direction finding system proposed by the present invention has comparable direction finding results to those of the traditional amplitude comparison direction finding system under the condition of reducing the number of channels.

[0052] Table 1 - Measurement Results Table

[0053]

[0054] The root mean square statistical formula is:

[0055]

[0056] Parameter meaning: i represents the i-th measurement angle, n represents the total number of measurement angles, DOA i represents the value of the i-th measurement angle, and ΔDOA i 2 represents the error of the i-th measurement angle, and DOA' i represents the value of the i-th theoretical angle.

[0057] As described above, the present invention can be preferably realized.

[0058] All the features disclosed in all the embodiments in this specification, or all the steps in the methods or processes implicitly disclosed, except for the mutually exclusive features and / or steps, can be combined and / or extended and replaced in any way.

[0059] As mentioned above, it is only a preferred embodiment of the present invention, and it does not impose any formal limitations on the present invention. Based on the technical essence of the present invention, any simple modifications, equivalent replacements, and improvements made to the above embodiments within the spirit and principles of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for direction finding by amplitude comparison, characterized in that: A matching template is formed based on the amplitude of the direction finding channel, and the measurable template of the new signal is compared with the stored template to determine the incoming direction of the new signal.

2. The amplitude comparison direction finding method according to claim 1, characterized in that: The number of direction finding channels is M; where M≥2 and M is an integer.

3. The amplitude comparison direction finding method according to claim 1, characterized in that: The following steps are involved: S1, combining signals transmitted by N antennas to generate M combined signals, and extracting the amplitudes of the M combined signals; wherein N ≥ 2 and N is an integer; S2, generates a template vector by linearly combining the amplitudes of the M-channel combined signals, and stores the theoretical template vectors of all incoming wave angles; S3, when a new signal is incident on the N antennas, the measurable template of the new signal is compared with the stored template to determine the incoming direction of the new signal.

4. The amplitude comparison direction finding method according to claim 3, characterized in that: The angle corresponding to the minimum mean square error is selected as the signal arrival direction.

5. The amplitude comparison direction finding method according to claim 3, characterized in that: N-way antennas can be set to attenuate, and the attenuation amount can be adjusted.

6. The amplitude comparison direction finding method according to claim 5, characterized in that: The attenuation is adjusted by a pre-emptive search method.

7. The amplitude comparison direction finding method according to claim 5, characterized in that: The attenuation is 10dB.

8. The amplitude comparison direction finding method according to any one of claims 3 to 7, characterized in that: N=4, M=3.

9. The amplitude comparison direction finding method according to claim 8, characterized in that: The four antennas are arranged in the directions of 0°, 90°, 180° and 270° respectively, and the four antennas divide the 360° direction-finding range into 8 sub-areas.

10. A comparison amplitude direction finding system, characterized in that: A method for amplitude comparison and direction finding for implementing any one of claims 1 to 9, comprising an antenna, an amplitude comparison and direction finding front end, an amplitude extraction branch, and an amplitude comparison and direction finding module which are sequentially communicatively connected; wherein the amplitude comparison and direction finding front end is used to combine the signals transmitted by the antennas to generate a combined signal, the amplitude extraction branch is used to extract the amplitude of the combined signal, and the amplitude comparison and direction finding module is used to compare a measurable template of a new signal with a stored template to determine the incoming direction of the new signal.

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