Design of E-Band FMCW Radar Transceiver Circuit and Module for Multistatic Drone-Borne Synthetic Aperture Radar

Abstract

Recent drone swarm demonstrations have highlighted the capability of drone-borne SAR systems to cover wide areas simultaneously. These multiple drone configurations offer enhanced angular diversity, leading to enhanced ground target information. Generally, a frequency-modulated continuous-wave (FMCW) radar system can operate in a monostatic mode, in which transmitters (TXs) and receivers (RXs) are co-located; or in a multistatic mode, in which they are separated. For multistatic configurations, the synchronization between the TXs and RXs must be addressed for drone-borne SAR image reconstruction from multiple received signals. In this work, we present an E-band drone-borne multistatic FMCW radar transceiver (TRX) which enables multiple drones to cooperate for SAR imaging by wirelessly sharing the reference chirp signal. Using integrated RF switches, the TRX can be configured for monostatic or two distinct multistatic modes. In the multistatic modes, the reference chirp signal can be relayed drone-to-drone or broadcast from the source drone to other drones transmitting or receiving SAR signals. The module incorporates microstrip comb-line antennas for radar and planar Yagi-Uda array antennas for synchronization. The modules can detect targets up to 70m in monostatic and multistatic modes with an approximate 20-dB SNR.