A Code-Domain RF Signal Processing Front-end for Simultaneous Transmit and Receive with 49.5 dB Self-Interference Rejection, 12.1 dBm Receive Compression, and 34.3 dBm Transmit Compression

This paper demonstrates a code-domain transceiver that incorporates a transmit (TX) modulator and receive (RX) RF signal correlator. We propose a transmission gate switch with 12.1-dBm/23.1-dBm P1dB/IIP3 for both RF correlation and filtering and rejects TX self-interference by 49.5 dB. An integrate-and-dump N-path filter improves rejection by 8 dB. The RX power consumption is 18 mW at 1 GHz. The TX modulator operates to RF power levels up to 34.3 dBm and consumes less than 40 mW for 300 Megachip-per-second (Mc/s). Over the air testing demonstrates synchronization with Barker codes.