A Receiver Architecture for Dual-Antenna Systems

The signals received by two antennas can be processed by a single time-shared receiver but only in the absence of interferers and channel-select filters. A low-IF receiver architecture is introduced that translates two antenna signals to positive and negative frequencies in the complex domain, reducing the number of baseband A/D converters by a factor of two. A dual-receiver prototype designed and fabricated in 0.18-mum CMOS technology provides a sensitivity of -72 dBm with an EVM of -25 dB for 64 QAM signals while drawing 60.2 mW from a 1.8-V supply.