Novel Active Bandpass Switchplexer for RF Transceiver Front-End Applications

In this paper, the design of RF transceiver front-end using a novel multifunction microwave circuit is proposed. By designing one arm of the proposed active bandpass switchplexer as a bandpass power amplifier (PA) and the other arm as a single-to-balanced bandpass low-noise amplifier (LNA), the resulted multifunctional microwave filtering device thus effectively integrates the functions of single-pole-double-throw RF switch, bandpass filter, balun, PA, and LNA. In this way, all the function blocks between the antenna and up/down converters of a single-band time-division duplex transceiver front-end can be integrated into a single circuit. Compared to the previous works on multifunction microwave circuit designs, the proposed active bandpass switchplexer features the highest number of integrated functions. A printed circuit board-based design example of the proposed active bandpass switchplexer is presented to validate the proposed design concept and to demonstrate the performance achieved.