For Td-scdma System Cmos Integrated Transmit / Receive Switch Design

This dissertation focuses on the transmit-receive (T/R) switch. Two CMOS T/R switches have been designed in a 0.35μm standard CMOS technology for TD-SCDMA at 2.0GHz.The first T/R switch is a symmetric single-pole double-throw (SPDT) T/R switch without passive components. The switch exhibits 1.08dB insertion loss, 13.5dBm power 1dB compression point (P1dB) and 27dB isolation at 2.0GHz. The low insertion loss is achieved by optimizing the transistor widths and bias voltages, by minimizing the substrate resistances, and by DC biasing the transmit and receive nodes, which decreases the capacitances while increasing the P1dB. The switch has available insertion loss, isolation and P1dB for TD-SCDMA applications.The second T/R switch design introduces an inductive substrate bias technique. In the transmit mode, the switch exhibits 1.06dB insertion loss, 17.4dBm P1dB and 35dB isolation at 2.0GHz. In the receive mode, the switch achieves 1.12dB insertion loss, 12.8dBm P1dB and 25.5dB isolation at 2.0GHz. These results show that the switch design is suitable for TD-SCDMA applications.