Miniaturized balanced low noise amplifier for TD-SCDMA application

A miniaturized balanced low noise amplifier for TD-SCDMA application is presented in this paper. Using the PHEMT devices, the proposed low noise amplifier with miniaturized quadrature hybrid coupler is designed in terms of stability and matched characteristics. Simulated by AWR MWO software, the amplifier is fabricated on a PTFE board. The compact quadrature hybrid coupler reduces the size of the circuit greatly. Over the operating frequency band (1.85-1.95 GHz), the measured results demonstrate an excellent performance with a low noise figure of less than 0.9 dB, gain of higher than 31 dB, inband flatness of less than 1 dB, S11 of less than -15 dB, and S22 of less than -13dB.