Design And Implementation Of MMIC-based Millimeter Wave MIMO Radar

Inspired by Multiple-Input Multiple-Output(MIMO)in communication systems,MIMO radar has drawn extensive research attention.MIMO radar system can realize spatial and frequency diversities simultaneously,which can effectively reduce the influence of multipath effect on radar performance,and thus has better anti-interference and anti-stealth capability,than traditional radars in the target tracking and recognition applications.With the development of electronic technology,which makes Monolithic Microwave Integrated Circuits(MMICs)could be fabricated and brings the advantages like small size,light weight,high reliability,low price,etc..In this paper,we develop a millimeter-wave MIMO radar system based on MMIC chips.More specifically,the main work and research results are shown as follow:1.First we study the system characteristics of MIMO radars,like the distance and velocity measurement capability and the distance-velocity coupling in echoed linear frequency modulated continuous wave radar signals.We also evaluated the impact of zigzag frequency modulated continuous wave to the radar performance.2.The digital beamforming technology of MIMO radar is studied.Based on the traditional adaptive linear constrained minimum variance adaptive digital beamforming algorithm,an adaptive digital beamforming algorithm with reduced dimensionality and minimum variance is designed and implemented on FPGA.Compared with the traditional linear constrained minimum variance algorithm,the calculate amount is greatly reduced,which is beneficial to hardware implementation.The simulation results show that the new algorithm improves the clutter suppression by 5-10 dB over the traditional algorithm.The experimental results show that the algorithm only needs 0.57 ms to update the weight coefficient when is implemented on Xilinx ZYNQ FPGA,which achieves the purpose of real-time update.The proposed algorithm is encapsulated into a IP core for easy use in other FPGA systems.3.Based on a microprocessor S32R274 with the PowerPC architecture,we design signal processing system.The whole radar system has the ability to process echo signals in real time to detect and track interested targets.Different waveform parameters in different modes can be configured by the host computer software to adapt to different application scenarios.The maximum unblurred speed is 100km/h,the speed resolution is up to 0.39km/h,the distance resolution is up to 37.5mm,and the transmission channel of the original echo data is reserved.The received radar echo can be collected by the host computer software for the convenience to be verified by other related algorithms.The experimental results indicate that all design requirements are met by the radar system.