Design of FMCW millimeter-wave radar for helicopter assisted landing

This paper discusses the design and construction of a compact, ultrafast, monostatic frequency modulated continuous wave (FMCW) millimeter-wave radar, operating at 94.75 GHz, intended to be used as a helicopter assisted landing sensor. A high speed direct digital synthesizer is used to generate the baseband FM signal. Custom transmitter/receiver baseband boards are designed to up/down-convert the frequency modulated (FM) signal to an appropriate IF before it can be connected to the W-band RF frontend. A high-gain lens horn antenna is used in the RF frontend, in conjunction with other waveguide-based W-band components. A Xilinx FPGA is used in the backend data processing, preferred over conventional DSPs because of its speed. The whole system is packaged in an aluminum casing, with dimensions of 9’ × 11’ × 11’ and weighing under 20 lbs.