A D-Band 1Tx 4Rx Mid-Range Automotive CMOS FMCW Radar

A 135 GHz frequency modulated continuous wave (FMCW) radar system is presented using 1Tx and 4Rx chips in 28-nm CMOS. The radar system is fully integrated on a planar substrate using an active array architecture, where the chip directly feeds the patch antenna, eliminating the need for costly packaging and antenna technology. To compensate for the aperture size reduction of the receiving antenna in the D-band compared to the W-band, channel integration across the four receiving channels is used to enhance the SNR during the constant false alarm rate (CFAR) process. Measured results demonstrate successful detection of a target vehicle at a distance of 112 m with an SNR of 14.58 dB, showing the feasibility of automotive D-band radar systems for high-resolution and long-range sensing.