A 5 GHz radio front-end with automatically Q tuned notch filter

Low voltage designs of front-end components for 5 GHz radio applications are presented. A notch filter with automatic Q tuning is integrated with the LNA to provide image rejection. On-chip transformers are used extensively in the receiver. The receiver had a gain of 19.8 dB, noise figure of 4.5 dB, an IIP3 of -11.5 dBm, and the VCO had a phase noise of -116 dBc/Hz at 1 MHz offset.