Multi-function Array Radar Signal Processing Based On FPGA

Multi-function array radar is a new system radar produced in the field of radar since 21 th century,and it can realize the work mode of MIMO radar and phase array radar by controlling emission signal of each antenna array element flexibly.MIMO radar transmits multiple orthogonal waveforms to form a wide beam in the space,which has a strong ability of anti-interference and weak target detection.Phase array radar transmits coherent waveforms which can form high gain and narrow beam in the space to achieve target detection.Multi-function array radar has the two systems of MIMO and phase array radar,and it can change it's work mode and transmitting waveforms according to the environment to achieve effective detection of target.In the background that the target information is becoming increasingly complex,the multi-function array radar's characteristics of multi task and flexible work mode can better adapt to the complexity of the different environment of target.Multi-function array radar includes traditional phase array radar and MIMO radar,so we adopt the design scheme which includes two work modes in the process of signal processing,compared to traditional phase array radar,the main difference of MIMO radar in signal processing is simultaneous multi-beam forming and pulse synthesis.In function,multi-function array radar covers the kinds of function,such as work mode switch,parameter control and target search and tracking,which puts forward a higher requirement for the allocation of hardware resources,FPGA has the advantages of high throughput,low latency,high parallelism and high stability,and FPGA has rich resources on it's chip,so it is suitable for multi-channel DBF processing and part of realization of controlling function.This thesis introduces the basic working principle of phased array radar and MIMO radar,establishes two kinds of radar echo signal models,and analyzes the energy distribution characteristics of their respective working waveforms.Then the theory of digital beam forming and pulse compression is studied.At the same time,the theory of array amplitude and phase error is introduced.Based on the array amplitude-phase error model,a method of removing the high side lobe object is proposed.Then the signal processing flow of phased array radar and MIMO radar is discussed.Finally,the design scheme of real-time processing of a multi-function array radar developed in FPGA is given.FPGA adopts the pipeline-type processing method to realize functions such as optical fiber data reception,data analysis,DBF,and array error correction,and at the same time it realizes control functions such as sending data to the DSP and uploading commands to the radar.