Switch architecture for TDMA and FDD multiplexing

摘要

Switching circuitry is provided for a mobile terminal having a Time Division Multiple Access (TDMA) mode of operation and a Frequency Division Duplex (FDD) mode of operation. The switching circuitry includes resonant tank circuitry having a controllable resonant frequency and an output coupled to an antenna of the mobile terminal. The switching circuitry also includes a transmit switch that couples TDMA transmit circuitry to an input of the resonant tank circuitry when transmitting in the TDMA mode of operation, a receive switch that couples TDMA receive circuitry to the input of the resonant tank circuitry when receiving in the TDMA mode of operation, and a FDD switch that couples a FDD transceiver to the output of the resonant tank circuitry when in the FDD mode of operation. The controllable resonant frequency is controlled such that the transmit and receive switches are isolated from the antenna during FDD operation.

主权项

1. Switching circuitry for a mobile terminal having a Time Division Multiple Access (TDMA) mode of operation and a Frequency Division Duplex (FDD) mode of operation comprising:
resonant tank circuitry having a controllable resonant frequency controlled by at least one control signal and an output coupled to an antenna; at least one receive path switch adapted to couple at least one receiver front end to an input of the resonant tank circuitry when the mobile terminal is in a receive mode during TDMA operation; at least one transmit path switch adapted to couple at least one transmit circuit to the input of the resonant tank circuitry when the mobile terminal is in a transmit mode during TDMA operation; and a FDD switch adapted to couple a FDD transceiver to the output of the resonant tank circuitry during FDD operation; wherein the at least one control signal is provided such that the resonant tank circuitry substantially isolates the at least one receive path switch and the at least one transmit path switch from the antenna during FDD operation.