A?analog?baseband?(ABB)?circuit?with?reconfigurable?gain?and?bandwidth,?high?linearity?and?low?noise?for?77GHz?Mm-wave?radar?application?is?presented.?The?ABB?consists?of?three-stage?programmable?gain?amplifiers?(PGAs),?A?fiver?order?reconfigurable?Butterworth?low-pass?filter?(LPF)?and?three?active?DC?offset?cancellation?(DCOC)?loops.?The?total?gain?range?from?18dB?to?70dB?with?an?average?step?of?6dB,?and?the?bandwidth?of?the?LPF?is?reconfigurable?from?200kHz?to?2MHz.?The?minimum?noise?figure?of?ABB?is?24dB?and?IIP3?at?highest?gain?is?-52dBm?.The?circuit?has?been?implemented?in?65nm?CMOS?process.?It?occupies?1.2*0.93?mm2?area?and?consumes?14mA?current?from?1V?power?supply.