77GHz Low-Cost Single-Chip Radar Sensor for Automotive Ground Speed Detection

A new 77 GHz single-chip radar sensor has been developed, which encapsulates a GaAs p-HEMT transceiver MMIC with an on-chip patch antenna in a resin-molded package integrated with a resin collimating lens on the top to achieve an EIRP of 13.5 dBm and a receiving gain of 8 dB. The packaged sensor, measuring 6.5times4.4times6.0 mm³ with only DC and baseband- frequency leads, offers ease of handling with an extreme low-cost potential for a variety of applications. When adopted to an automotive ground speedometer integrated with an signal processing unit, the sensor demonstrated accurate and reliable detections of vehicle speed with a standard deviation of 1.5% under normal driving conditions.