An RF-MEMS based SP4T switched LNA MMIC used in a 24 GHz beam-steering antenna module

This paper presents an RF-MEMS SP4T switched LNA MMIC used in a 24 GHz beam-steering antenna module. The SP4T LNA has a measured gain of 10–16 dB at 16–30 GHz (NF=2.6–3.0 dB at 16–26 GHz) with up to 37 dB of isolation at 24 GHz when one of the four MEMS switches are closed while the other switches are open. To the authors' knowledge, this work represents a first-time realisation of a MEMS SP4T LNA MMIC used as an on-chip active beam-switching network in an adaptive antenna. The experimental results successfully demonstrate that the MEMS SP4T LNA can be used to control the antenna beam in 4 different directions between −55° and 45° in the same plane.