A dual-band MEMS PA study for mobile communication systems

Abstract

This paper described a dual-band PA with MEMS capacity switch, and it is composed of the series MEMS capacity switch, cascode amplifier and other circuit, and gets the dual-band of 2.1 GHz /2.3 GHz PA by the switch capacity variation. The first, a MEMS capacity switch is designed, analyzed by EDA of HFSS, and obtain the capacitive curve with 2.1 GHz and 2.3 GHz, insert loss is about 2 dB and isolation is about 50 dB. The second, the MEMS switch is applied in the PA circuit, and the circuit model is designed basing on the CMOS technology. The performance is obtained by EDA of ADS simulation, and the gain is 12.4 dB and 11.5 dB with 2.1 GHz and 2.3 GHz and PAE is about 50% when output 25 dBm at two band. MEMS switches are used to implement a variable filter and matching network that allows the PA to realize the dual-band and high efficiency. It has good performance, and it may be applied for mobile communications systems, such as 3.5 G (generation), 4 G mobile communications systems.