A temperature-robust analog baseband chain for automotive radar

This paper presents an analog baseband chain for automotive radar applications. The baseband chain consists of a fifth-order Butterworth filter with a reconfigurable bandwidth and a 3-stages programmable gain amplifier (PGA) with DC offset cancellation (DCOC). To achieve robust temperature stability, an amplifier with resistive feedback topology is employed, while temperature compensation technique is also proposed and realized. The chip was implemented in a 65-nm CMOS technology with a 5.6mW power consumption from a 1.2V supply. The simulation results show that the analog baseband achieves a reconfigurable gain range from 18dB to 72dB with 6dB per step, and a reconfigurable 1-dB bandwidth range from 100kHz to 5MHz. The gain of the entire baseband changes by less than 1.4dB from -40°C to 125°C for all steps, while the 1-dB bandwidth changes 0.9MHz at 5MHz step.