$W$ -Band Multichannel FMCW Radar Sensor With Switching-TX Antennas

In this paper, a multichannel frequency-modulated continuous wave (FMCW) radar sensor with switching-transmit (TX) antennas is developed at $W$ -band. To achieve a high angular resolution, a uniform linear array consisting of 5 switching-TX and 12 receive (RX) antennas is employed with the digital beamforming technique. The overall radar front-end module comprises a $W$ -band transceiver and TX/RX antennas. A multichannel transceiver module consists of 5 up-conversion and 12 down-conversion channels, where one of the TX channels is sequentially switched ON. The developed radar sensor generates multiple digital beams with high gain, low side lobe level, and narrow beamwidth. The design of each component in the radar module is described with the measurement results. The assembled FMCW radar sensor exhibits a measured angular resolution of less than 2°, and a field of view of approximately 60°.