Multi-Band and Reconfigurable Front-Ends for Flexible and Multi-Functional RF Systems

This report summarizes some of the recent results at FOI with respect to multi-band and reconfigurable front-ends for flexible and multi-functional RF systems. Firstly, we report on a frequency agile X-band smart skin digital beamforming antenna based on using an 8-10 GHz tunable active filter and an image rejection mixer in a receiver GaAs MMIC. Secondly, we have also investigated the possibility of using RF MEMS based reconfigurable matching networks for realizing tunable bandpass LNAs with even wider tuning ranges (e.g. 6-10 GHz could be possible according to our simulations). Finally, we study a system concept for a Ka-band multi-functional electronically steerable antenna (ESA) on a small UAV based on using sub-arrays with low-loss MEMS phase shifters. The results show that adequate RF performance (in terms of 2 dB of average losses at 35 GHz) can be possible to achieve with a Ka-band 4-bits MEMS phase shifter design made on quartz.