Wideband Miniaturized Planar Patch TX/RX Antenna Arrays For Microwave FMCW Doppler Radars

Wideband miniaturized patch linear transmit and planar receive (TX/RX) antenna arrays are presented for microwave FMCW radar applications. RT/duroid 5880LZ laminate is used as the substrate to miniaturize the antenna elements and to provide the required FMCW short range radar system bandwidth. The resonance frequency and bandwidth are set to be 5.8 GHz and 400 MHz. The TX antenna is a 1x4 linear array while the RX antenna is a 2x4 planar array to improve the gain and SNR performance of the radar receiver. TX/RX arrays show pure radiation patterns with proper alignment and the gain of ~12.9/15.2 dB and 15.5/17.5 dB of front-to-back ratio, respectively while achieving a ~70 dB of TX-to-RX isolation.