A 24-30 GHz GaAs MMIC Asymmetric SPDT Switch with Integrated Bandpass Filter in RX Mode

In this paper, a 24-30 GHz GaAs monolithic microwave integrated circuit (MMlC) asymmetric single-pole double-throw (SPDT) switch with integrated bandpass filter in receiving (RX) mode is presented. Due to the different requirements for receiving and transmitting (TX) mode in frontend applications, an asymmetric design is adopted. The TX chain utilizes cascaded series-parallel units and stacked transistor stages to increase power handling capacity and ensure isolation. In RX chain design, a filtering design based on multiple transmission paths is integrated into the switch to reduce interference from other frequency bands. The proposed asymmetric filtering SPDT switch is implemented in 0.10-µm GaAs pseudomorphic highelectron mobility transistor (pHEMT) process and demonstrates low insertion loss and high-power handling capabilities. Simulation results show RX mode with a maximum in-band insertion loss of 1.77 dB and good selectivity, while TX mode has a 1.34 dB of maximum insertion loss and IP1dB of more than 37 dBm. The chip's total area is 1.15 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, showing a compact size.