A non-reciprocal radio frequency transceiver front end utilizing multiple time-varying transmission lines (TVTLs) implemented using distributed modulated capacitors (DMC) to exploit time-varying properties of transmission line structures to isolate the transmit and receive signals. The TVTLs are coupled at an input side to an antenna and ground through a first 90 degree coupler, and the outputs of the TVTLs are coupled through a second 90 degree coupler for connection to a receiver and transmit circuit, respectively. The apparatus allows simultaneously operating a transmitter and receiver sharing a single antenna (or single antenna array).
