Design of electronically switchable single-to-balanced bandpass low-noise amplifier

In this work, the design of novel electronically switchable single-to-balanced bandpass low-noise amplifier (LNA) is proposed so as to improve the level of integration for radio frequency (RF) front-end design. By realising the input matching circuit with an electronically switchable bandpass filter and the output matching circuit as a bandpass balun, the LNA can also exhibit the functions of RF switch, bandpass filter and balun simultaneously. In this way, more compact circuit size and less mismatch loss can then be obtained in RF front-end design. To demonstrate the performance and effectiveness of the proposed design method, a 2-GHz electronically switchable single-to-balanced bandpass LNA is implemented on printed circuit board using packaged E-pHEMT transistor.