A Closed-Loop Pulsed Power Control Circuit for UWB 24 GHz Automotive Radar Transmitter

This paper presents a closed-loop power control circuit for a UWB pulse radar transmitter. It provides over 10 dB of dynamic power control on a 24 GHz pulsed signal with pulse width of 1.59 nS and duty cycle of 0.5%. The circuit consists of an on-board directional coupler, a three-stage power detector and an error amplifier. All the circuits are integrated on the same chip with the transmitter in a SiGe HBT process. Temperature compensation schemes are applied to improve the circuits temperature stability. The circuit consumes 2.7 mA current and occupies only 360 times 480 mum
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