小型化R波段限幅低噪声放大器设计

Design of a Miniature R-Band Limiting Low Noise Amplifier

设计了一种小型化限幅低噪声放大器。采用Lange桥平衡结构，在实现低噪声的同时，得到较小的输入输出电压驻波比。采用集总参数和分布参数元件，实现了各级匹配。该小型化限幅低噪声放大器工作在R波段（2．1～2．5GHz），噪声系数低于1dB，输入输出驻波系数小于1．4，增益大于31dB，带内增益波动只有±0．2dB。通过SP2D开关实现两路输出，输出隔离度大于42dB。

A miniature amplitude limited LNA was designed, in which Imnge coupler was used to obtain smaller VSWR, and lumped and distributed components were employed to make a perfect match to the circuit. Operating in the frequency range from 2.1 GHz to 2.5 GHz, the LNA achieved a noise figure less than 1 dB, a VSWR below 1. 4, and a gain up to 31 dB with in-band fluctuation less than ±0. 2 dB. The circuit realized two RF outputs with an isolation over 42 dB by using a high performance SP2D switch.