Multi-panel switched beam forming method and device based on phase center compensation

Abstract

The application provides a multi-array switching beam forming method and device based on phase center compensation, wherein the method comprises the following steps: uniformly distributing N antenna arrays around a carrier with an interval of M degrees, wherein N*M=360; switching the arrays in a hysteresis mode, namely, switching to the next array after the incident signal crosses the critical surface between two arrays by an angle of θ; when judging the switching of the antenna array, performing phase compensation on the steering vector; combining the generated phase-compensated steering vector to calculate the weighting value, weighting the original signal to obtain a combined signal, and outputting the combined signal to a baseband for processing. The application realizes full-space coverage of the receiving beam, adopts a phase center compensation algorithm when switching the array, and ensures the phase continuity of the beam forming between the multi-array antenna arrays.

Description

TECHNICAL FIELD

[0001] The present application relates to a multi-array switching beam forming method based on phase center compensation, belonging to the field of array signal processing. BACKGROUND

[0002] With the continuous development of array signal processing, array adaptive anti-jamming and other technologies, the technology of full-space directional active antenna is more and more widely concerned. The full-space directional active antenna can realize beam pointing under different attitudes of the carrier, and can realize wideband interference suppression, and the application in the field of satellite communication, mobile communication and the like is gradually enhanced, and the requirement for the phase consistency of the beam forming of the full-space directional active antenna is high.

[0003] At present, the full-space directional active antenna mainly adopts mechanical scanning technology and omnidirectional single antenna technology. The characteristics of the two technologies are as follows:

[0004] Mechanical scanning: the beam pointing adjustment period is relatively long.

[0005] Omnidirectional antenna: cannot realize high gain and array anti-jamming processing by using array.

[0006] In order to solve the shortcomings of the above two technologies, the full-space directional active antenna technology emerges as the times require, which solves the problem of long beam pointing adjustment period of mechanical scanning technology, and also solves the problem of high gain and array anti-jamming processing by using array of omnidirectional antenna, but after using the technology, the problem of phase jitter is easily generated in the process of switching of multi-array antenna array, and thus the problem of phase inconsistency is easily generated. SUMMARY

[0007] In view of the problem that phase jitter is easily generated in the process of switching of multi-array antenna array, and thus the problem of phase inconsistency is easily generated, the present application aims to provide a multi-array switching beam forming method and device, which ensures the phase continuity of beam forming between full-space multi-array antenna arrays.

[0008] In order to achieve the object of the present application, the present application provides a multi-array switching beam forming method based on phase center compensation, which adopts the following technical scheme:

[0009] The method comprises the following steps:

[0010] Step 1. N antenna arrays are uniformly distributed around the carrier with an interval of M degrees, wherein N x M = 360, so as to ensure that the N arrays can cover 360 degrees;

[0011] Step 2. Switch the array in a hysteresis manner, that is, when the incident signal crosses the critical surface of two arrays by θ degrees, switch to the next array;

[0012] Step 3. When judging the antenna array switching, calculate the phase difference between the incident signal to the two antenna arrays before and after switching

[0013] Step 4. According to the calculated phase difference, phase compensation is performed on the steering vector;

[0014] Step 5. Combine the generated phase-compensated steering vector A θ , calculate the weight, and obtain the combined signal after weighting the original signal, and output the combined signal to the baseband for processing.

[0015] Further, the sample matrix inversion algorithm combines the generated phase-compensated steering vector A θ to calculate the weight.

[0016] Further, the phase compensation method for the steering vector is as follows:

[0017] Let the distance of the incident signal to the two arrays be ΔD, assume that the frequency of the communication signal is Fr, the speed of light is C, and the phase difference of the satellite signal to the array A and the array B is :

[0018]

[0019] Assume that the original steering vector is A0, and the phase-compensated steering vector is A θ :

[0020]

[0021] According to another aspect of the present application, the present application provides a multi-array switching beam forming device based on phase center compensation.

[0022] The device includes N antenna arrays, an analog down-conversion and signal processing board, and the N antenna arrays are uniformly distributed around the carrier with an interval of M degrees, where N x M = 360.

[0023] The signal processing board includes an AD chip and a digital signal processing module.

[0024] The antenna array receives a signal, which is transmitted to the digital signal processing module after A / D conversion to form a digital signal through the analog down-conversion module. The digital signal processing module judges the incident angle of the received signal, and when the incident signal is parallel to the interface between the two arrays, it further judges whether the incident signal offset angle satisfies the specified offset angle θ. If it satisfies, phase compensation is performed on the steering vector, the weight is calculated combining the generated phase-compensated steering vector, the original signal is weighted to obtain the combined signal, and the combined signal is output to the baseband for processing.

[0025] The application provides a multi-array switching beam forming method and device based on phase center compensation, which realizes full-space coverage of a receiving beam; and a phase center compensation algorithm is used in array switching, so as to ensure phase continuity of beam forming between full-space multi-array antenna arrays. BRIEF DESCRIPTION OF DRAWINGS

[0026] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is apparent that the accompanying drawings are only some embodiments of the application and based on these drawings, other drawings can be obtained by those of ordinary skill in the art without any creative effort.

[0027] Figure 1 An antenna array distribution diagram provided by a specific embodiment of the application is shown;

[0028] Figure 2 An incident signal and an antenna array diagram provided by a specific embodiment of the application are shown;

[0029] Figure 3 A multi-array switching beam forming flowchart based on phase center compensation provided by a specific embodiment of the application is shown;

[0030] Figure 4 A multi-array switching beam forming device diagram based on phase center compensation provided by a specific embodiment of the application is shown;

[0031] Figure 5 A phase jump diagram when a 5-degree delay switching array is provided by a specific embodiment of the application is shown;

[0032] Figure 6 Phases of receiving signals at different angles in a full space after phase compensation provided by a specific embodiment of the application are shown. DETAILED DESCRIPTION

[0033] It should be noted that the embodiments and features in the application can be combined with each other without conflict. The technical solutions in the embodiments of the application will be described clearly and completely with reference to the drawings of the embodiments of the application. Obviously, the described embodiments are only some of the embodiments of the application, not all. The description of the at least one example embodiment is actually only illustrative, not as any limitation on the application and use or use of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without any creative effort are within the scope of protection of the application.

[0034] The multi-array switching beam forming method based on phase center compensation provided by the embodiment of the application adopts the technical scheme comprising the following steps:

[0035] Step 1. N antenna arrays are uniformly distributed around the carrier with an interval of M degrees, wherein N*M=360, so as to ensure that the N arrays can cover 360 degrees, as shown in the figure. Figure 1

[0036] Step 2. The arrays are switched in a hysteresis manner.

[0037] In the switching process of the arrays, the hysteresis switching manner is adopted to avoid the problem of frequent switching of the arrays when the elevation angle of the incident signal relative to a certain array fluctuates in a small range near M / 2 degrees. As shown in the figure, when the incident signal gradually changes from the array N-1 (i.e. array A) to the array N (i.e. array B), when the incident signal is parallel to the junction surface of the array N-1 and the array N, the elevation angle of the incident signal relative to the array N-1 (i.e. array A) and the array N (i.e. array B) is M / 2 degrees, and theoretically the array can be switched from N-1 to N at this time, and actually the array is switched from N-1 to N after the incident signal moves to be parallel to the Y axis and then is deflected by a small angle θ. Figure 2

[0038] Step 3. Calculation of phase difference of arrays in hysteresis switching

[0039] In the carrier coordinate system, it is assumed that the coordinates of the satellite are (Xo, Yo, Zo), the coordinates of the phase center of the array A are (Xa, Ya, Za), and the coordinates of the phase center of the array B are (Xb, Yb, Zb). According to the basic principle of array antenna, in the case of considering only the far field signal, the distances of the satellite signal to the array A and the array B are Da and Db respectively:

[0040]

[0041]

[0042] The distance difference ΔD of the incident signal to the array A and the array B is:

[0043] ΔD=Da-Db (3)

[0044] It is assumed that the frequency of the communication signal is Fr, and the speed of light is C (C=3×10 8 m / s). The phase difference of the satellite signal to the array A and the array B is

[0045]

[0046] Step 4. Compensation of steering vector phase​​

[0047] When judging the antenna array switching, the phase compensation is performed on the steering vector.

[0048] Supposing the original steering vector is A0, the phase compensated steering vector is A θ , and

[0049]

[0050] Step 5. The weight is calculated by using the sample matrix inversion algorithm combined with the phase compensated steering vector A θ generated in step 4.

[0051] Step 6. The combined signal is obtained by weighting the original signal with the weight calculated in step 5, and the combined signal is output to the baseband for processing.

[0052] Based on the same concept, the application also provides a device for multi-array switching beam forming based on phase center compensation.

[0053] The device for multi-array switching beam forming based on phase center compensation provided by the application is described below, and the device for multi-array switching beam forming based on phase center compensation described below can be referred to each other with the method for multi-array switching beam forming based on phase center compensation described above.

[0054] The device for multi-array switching beam forming based on phase center compensation provided by the application includes N antenna arrays, an analog down-conversion module, and a signal processing board, as shown in the following figure. Figure 3

[0055] The antenna array adopts a multi-element planar circular array, and the N antenna arrays are uniformly distributed around the carrier with an interval of M degrees, wherein N×M=360, so as to ensure that the N arrays can cover 360 degrees.

[0056] The signal processing board includes an AD chip and a digital signal processing module.

[0057] The antenna array receives signals, and after analog down-conversion and A / D conversion, the digital signals are transmitted to the digital signal processing module. The digital signal processing module judges the incident angle of the received signal, and when the incident signal is parallel to the junction surface of array N-1 and array N, it further judges whether the incident signal offset angle satisfies the specified offset angle θ. If yes, the phase compensation is performed on the steering vector, the weight is calculated by using the sample matrix inversion algorithm combined with the generated phase compensated steering vector, the combined signal is obtained by weighting the original signal, and the combined signal is output to the baseband for processing.

[0058] The application is further described below in combination with a specific embodiment.​

[0059] In this example, the antenna array adopts a 7-element planar circular array, and a signal with a center frequency Fr=2GHz is used as the array receiving radio frequency signal. The specific implementation steps are as follows:

[0060] Step one: evenly distribute the three array surfaces around the carrier with an interval of 120 degrees, and each array surface covers 120 degrees of space, completing full space coverage.

[0061] Step two: adopt a 5-degree delay switching mode, that is, when the incident signal is parallel to the Y axis, switch to the next array surface after 5 degrees from the critical point of the two array surfaces. The antenna array receives signals, performs analog down-conversion, and forms digital signals through A / D conversion for transmission to the digital signal processing module. The digital signal processing module determines the incident angle of the received signal, and when it is determined that the incident signal is parallel to the Y axis, it further determines whether the incident signal offset angle meets the specified 5-degree offset angle. If it meets, the phase compensation of the steering vector is performed.

[0062] Step three: calculate the phase difference with a delay angle of 5 degrees, a signal pitch of 5 degrees relative to array surface A, and an azimuth angle of 90 degrees. In this example, in the carrier coordinate system, the coordinates of the satellite are (0, 2614672.3, 29885840.9), the coordinates of the phase center of array surface A are (0, -0.2165, 0.125), and the coordinates of the phase center of array surface B are (0, 0.2165, 0.125). According to the basic principle of array antenna, considering only the far-field signal, the distances of the satellite signal to array surface A and array surface B are Da and Db, respectively:

[0063]

[0064]

[0065] The distance difference ΔD of the satellite signal to array surface A and array surface B is:

[0066] ΔD=29999999.85328655-29999999.81554811=0.037738438695669 The frequency of the communication signal in this example is Fr=2Ghz, and the speed of light is C (C=3×10 8 m / s). The phase difference of the satellite signal to array surface A and array surface B is

[0067]

[0068] Figure 5 A phase jump diagram when the array surface is switched with a delay of 5 degrees is shown.

[0069] Step four: the digital signal processing module phase compensates the steering vector. Assuming the original steering vector is A0, the phase compensated steering vector is A θ Substitute the result of step three into equation (5) to obtain

[0070]

[0071] Figure 6 The schematic diagram after phase compensation is shown.

[0072] Step five: the digital signal processing module calculates the weight value by using the sampling matrix inversion algorithm combined with the generated phase compensated steering vector, weights the original signal to obtain a combined signal, and outputs the combined signal to the baseband for processing.

[0073] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, and not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A multi-plane switching beamforming method based on phase center compensation, characterized in that: The method comprises the following steps: Step 1. Distribute N antenna arrays evenly around the carrier at intervals of M degrees, where N × M = 360. Step 2: Switch the antenna array face with hysteresis, that is, switch to the next array face after the incident signal has passed the critical plane of the two array faces by θ degrees; Step 3. When the antenna array is switched, calculate the phase difference between the incident signal and the two antenna arrays before and after the switch. Step 4. Perform phase compensation on the steering vector based on the calculated phase difference; Step 5. Combine the generated phase-compensated steering vector A θ , calculate the weight, and add it to the original signal to obtain the combined signal, which is output to the baseband for processing. The phase compensation method for the steering vector is as follows: Assume that the distance from the incident signal to the two arrays is ΔD, the frequency of the communication signal is Fr, the speed of light is C, and the phase difference between the satellite signal to array A and array B is for: Assume that the original steering vector is A0 and the phase-compensated steering vector is A θ for:

2. The multi-array switching beamforming method based on phase center compensation according to claim 1, characterized in that: The sampling matrix inversion algorithm is combined with the generated phase-compensated steering vector A θ Calculate weights.

3. A device for implementing the multi-array switching beamforming method based on phase center compensation according to claim 1, the device comprising N antenna arrays, an analog down-conversion module, and a signal processing board, wherein the N antenna arrays are uniformly distributed around a carrier at intervals of M degrees, where N×M=360; The signal processing board includes an AD chip and a digital signal processing module. The antenna array receives a signal, performs analog down-conversion, and A / D conversion to form a digital signal, which is then transmitted to a digital signal processing module. The digital signal processing module determines the incident angle of the received signal. When the incident signal is parallel to the interface between the two array surfaces, it determines whether the offset angle of the incident signal meets the specified offset angle θ. If so, phase compensation is performed on the steering vector, and a weight is calculated based on the generated phase-compensated steering vector. The weighted value is added to the original signal to obtain a combined signal, and the combined signal is output to the baseband for processing.

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