CN111190165A

CN111190165A - Serial beam forming implementation method

Info

Publication number: CN111190165A
Application number: CN202010018349.3A
Authority: CN
Inventors: 王冬华; 夏东方; 沈洋
Original assignee: 724th Research Institute of CSIC
Current assignee: 724th Research Institute of CSIC
Priority date: 2020-01-08
Filing date: 2020-01-08
Publication date: 2020-05-22
Anticipated expiration: 2040-01-08
Also published as: CN111190165B

Abstract

The invention relates to a method for realizing serial beam forming, and belongs to the technical field of radar signal processing. The invention firstly generates sub DBF coefficients matched with the sub DBF coefficients according to the combination of the optical fiber message formats, under the condition of not analyzing the I/Q data before the DBF of the N groups, the serial I/Q data of the M optical fibers are respectively multiplied by the corresponding sub DBF coefficients, and finally, summation is carried out, thereby synthesizing the I/Q data after the multi-channel DBF. The invention avoids the fussy I/Q data analysis process before parallel N groups of DBFs; under the condition of changing the number M of the optical fibers, only the sub DBF coefficients need to be updated, the FPGA software module can be multiplexed, and the expandability of the software architecture is effectively enhanced.

Description

Serial beam forming implementation method

Technical Field

The invention belongs to the technical field of radar signal processing.

Background

Digital Beam Forming (DBF) can form multi-channel elevation I/Q data to obtain elevation information of the detected object. After receiving the front-end I/Q data of the DBF sent by a plurality of paths of optical fibers, the traditional DBF implementation method firstly analyzes the parallel front-end I/Q data of the plurality of paths of DBFs according to the message format of the sent optical fibers, and then multiplies the front-end I/Q data by DBF coefficients and sums the front-end I/Q data to synthesize the multi-channel elevation angle I/Q data. The DBF implementation method needs to analyze optical fiber data, and under the condition that the number of T/R channels is large, the programming efficiency of programmers can be effectively reduced; and under the condition of adding the T/R component in the later period, the expansibility of the software architecture is poor.

The invention adopts the serial beam forming method, does not need to analyze the sent optical fiber message, and avoids the fussy data analysis process; under the condition that the number of channels is changed by adding the TR component, only the sub DBF coefficient needs to be updated, and the expandability of the software architecture is greatly enhanced.

Disclosure of Invention

Aiming at the problems that the traditional DBF realization method needs to analyze parallel multi-path DBF front I/Q data and the software expansibility is poor under the condition of adding a T/R component, the invention can avoid a fussy DBF front I/Q data analysis process by a serial beam synthesis method, and the specific method comprises the following steps:

the TR component sends N groups of front DBF I/Q data through M optical fibers, each optical fiber consists of N/M groups of I/Q data, sub DBF coefficients matched with the sub DBF coefficients are generated according to optical fiber message format combination, each group of sub DBF coefficients are I, Q interval data streams generated according to channel sequence number combination, serial I/Q data in each optical fiber are multiplied by corresponding sub DBF coefficients respectively, N/M groups of results multiplied by the sub DBF coefficients in each optical fiber are summed, and finally N/M groups of summed results of the M optical fibers are accumulated, so that multi-channel elevation angle I/Q data are synthesized.

The present invention will be described in detail below with reference to the accompanying drawings.

Drawings

FIG. 1 is a process flow block diagram of the present invention.

Fig. 2 is a diagram of the effect of the multi-beam synthesis of the present invention.

Detailed Description

The invention realizes the multi-channel digital beam synthesis by a serial beam synthesis method. The specific process is as follows:

m optical fibers transmit N groups of I/Q data before DBF, and each optical fiber comprises N/M groups of I/Q data as shown in FIG. 1;

2. and according to the message protocol of each optical fiber for transmitting data, sub DBF coefficients DBF _1 and DBF _2 … DBF _ M matched with the serial I/Q data format are generated in a combined mode. Under each distance unit time, each optical fiber sends N/M groups of I/Q data, then the optical fiber 1 corresponds to 1 to N/M groups of channels, the optical fiber 2 corresponds to N/M +1 to 2N/M channels, the optical fiber M corresponds to (M-1) N/M +1 to N channels, and two groups of sub-DBF coefficients with different I, Q positions are respectively generated according to the channel sequence number sent by each optical fiber, as shown in FIG. 1;

3. let the DBF front complex signal be: i + j θ, DBF coefficient: i '+ j θ', the real part of the DBF post signal is: II '- θ θ', imaginary part is: i theta '+ theta I'. Multiplying the I/Q data before the N/M paths of serial DBF in each optical fiber with the two groups of sub DBF coefficients of the ith path respectively to obtain the I of the ith path respectively_iI_i'、θ_iθ_i'、I_iθ_i'、θ_iI_i'；

4. Each optical fiber respectively synthesizes N/M paths of I/Q data, and the I paths of signals after N/M paths of synthesis are as follows:

the Q path signals are:

5. synthesizing N paths of I/Q data of the M optical fibers to form a Kth optical fiber_iI/Q data of each elevation angle channel, and I signals of N paths of I/Q data after serial beam forming are as follows:

the Q path signals are:

fig. 2 shows the effect of beam forming by K elevation angles after serial beam forming.

Claims

1. A method for realizing serial beam forming is characterized in that: receiving N groups of DBF front I/Q data sent by M optical fibers, in order to avoid a complicated N groups of DBF front I/Q data analysis process, multiplying the M optical fibers with matched sub DBF coefficients respectively, summing N/M groups of results multiplied by the sub DBF coefficients in each optical fiber, and accumulating N/M groups of summed results of the M optical fibers, thereby realizing multi-channel digital beam synthesis.

2. A method for implementing serial beamforming according to claim 1, wherein: the sub-DBF coefficients multiplied by each fiber are generated from the sequential combination of the channels of I, Q data transmitted by each fiber.