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^o and 45^o in the same plane.