High-Linearity 76-81 GHz Radar Receiver with an Intermodulation Distortion Cancellation and High-Power Limiter

A highly linear 76–81 GHz direct conversion receiver has been fabricated in a 16 nm FinFet CMOS process for phased array radar applications. The receiver includes a Low Noise Amplifier (LNA), a semi active mixer, a passive filter and a baseband amplifier. A third order intermodulation distortion cancellation technique is implemented in the LNA and it is used to compensate for distortions in the entire receiver. The peak gain of the receiver is 36 dB with Input IP3 of -8.1 dBm and Noise Figure (NF) of 5.5 dB. The total power consumption of the receiver is 68 mW. To protect the LNA from high input power levels that affect the reliability of the transistors, an innovative limiter circuit is suggested to monitor the operating point of the first stage of the LNA, whereas the mmW signal path is not affected from this monitoring circuitry at tolerable power levels.