Simultaneous spatial and frequency-domain filtering at the antenna inputs achieving up to +10dBm out-of-band/beam P 1dB

Multi-antenna transceivers with beam-forming are recently gaining interest for low GHz frequencies ( 1dB , a fully passive switched-capacitor approach was presented in [4], providing P 1dB =+2dBm, but at a high noise penalty: NF=18dB. Here we propose to sum immediately at the baseband capacitors of passive mixer-first switched-RC downconverters. We show that this can render a direction-dependent RF impedance (spatial filtering) together with RF bandpass frequency filtering at lower noise and higher P 1dB .