A Single-Pole Nine-Throw RF Switch Design With GaAs PHEMT Technology

The design of a single-pole nine-throw (SP9T) multi-band RF switch with 0.5μm GaAs PHEMT technology has been described in this paper. It is designed for customer premises equipment (CPE) of the 2^nd and 3^rd generation mobile communication system, which covers both GSM and TD-SCDMA frequency bands in transceiver systems, including two transmission paths and four reception paths for GSM and three transmission-reception paths for TD-SCDMA or UMTS systems. A DC boost has been utilized to improve the linearity. The power capacity is 35dBm; the insertion loss (include loss of PCB) of each path is less than 1.2dB; the isolation is more than 40dB; the harmonic suppression ratio is more than 66dBc.