SiGe BiCMOS wide-band and tunable bandpass LNAs for adaptive multifunctional phased arrays

We study possibilities of implementing two key components for the RF front-ends of adaptive multifunctional phased arrays using a SiGe BiCMOS low cost technology. Measured data of an L-band to X-band LNA together with simulated results of a 5.2-5.5 GHz tunable bandpass LNA (active filter) show that adequate performance (in terms of high gain, low noise figure and power dissipation) potentially can be achieved while using small circuit areas. We further propose the use of low loss RF MEMS based TTDs as frequency tuning elements in tunable bandpass LNAs to be able to achieve wider center frequency tuning ranges (up to 20-50%) and also lower values of noise figure and power dissipation, respectively.