High-Linearity and Low-Noise Tunable C/X-Band GaN Filters for Robust Highly Integrated Front-Ends

This paper presents two tunable recursive active filters fabricated in 250 nm and 150 nm GaN MMIC processes. The first filter is tunable at 9.8-10.7 GHz with a measured gain of 13-15 dB, NF=8.3-8.9 dB, 45 of rejection (Q≤70) and input third order intercept point (IIP3) of 10-11 dBm (the output power was measured up to an input power of 0.9 W). A 7.3-8.2 GHz tunable GaN filter has a measured gain of 9-12 dB, NF=3.9-4.2 dB, 42 dB of rejection (Q≤20) and IIP3=5-11 dBm. The two tunable GaN filters demonstrate a relatively high gain, linearity and rejection as well as comparatively low filter noise figure values at C/X-band.