Fully-Integrated 94GHz Dual-Polarized TX and RX Phased Array ICs for 3D Real-Time Radar Imaging Applications

94GHz dual-polarized phased array transmitter (TX) and receiver (RX) ICs in 130nm BiCMOS and their module-level integration with antennas-in-package for radar imaging applications are presented. The TX IC integrates 16 transmitter front-ends with two independent outputs, a 1-to-16 power splitter, and IF-to-RF up-converter. The RX IC integrates 32 front-ends, two separate 16-to-1 power combiners, and two RF-to-IF down-converters, which can either support a 32-element phased array or 16-element polarimetric phased array. Both TX and RX ICs include IF/baseband circuitry, PLL, and digital circuitry including serial interface and front-end memory. A detailed system-level analysis of the phased-array ICs is presented highlighting architectural choices for robust operation at high temperatures. Novel mm-wave mixer design techniques are also described, which improve gain, linearity, and spur performance. On-wafer measurements at 94GHz show PSAT of 7.8dBm per channel for the TX and NF of 6dB for the RX. The TX/RX front-end phase shifting element achieves 1.6° phase steps for fine beam steering, and demonstrates orthogonal control of gain and phase. In addition, the IC demonstrates a robust functionality up to 105C, which is attributed to design robustness, architecture, modeling accuracy, and bipolar device improvement. Measurement results will be presented for the ICs, the modules, and a prototype 3D imaging system.