Frequency division duplex transceiver having n-path mixer bias current steering and sinusoidal voltage gate driver with transmit signal suppression in receive path

Abstract

A frequency division duplex transceiver comprises a quadrature hybrid coupler, and first and second baseband down-conversion circuits. The hybrid coupler provides a transmit signal (Tx) to an antenna, receives a receive signal (Rx) from the antenna, and receives a pre-transmit signal from a pre-transmit signal generator. Each baseband down-conversion circuit cyclically steers bias current to commutate mixer transistors in response to sinusoidal voltage gate drivers from a local oscillator signal generator. In the first baseband down-conversion circuit, a first N-path mixer receives an in-phase (I) receive component from the hybrid coupler, and a first baseband load reflects a quadrature (Q) pre-transmit component. In the second baseband down-conversion circuit, a second N-path mixer receives a Q receive component from the hybrid coupler, and a second baseband load reflects I pre-transmit component. The hybrid coupler provides Tx to the antenna in response to reflected Q pre-transmit component and reflected I pre-transmit component.