A 2.4 GHz MEMS based sub-sampling receiver front-end with low power channel selection filtering at RF

A sub-sampling RF front end which exploits the intrinsically high quality factor of MEMS devices for performing channel filtering directly at RF is proposed in this work. This narrow band filtering at RF also acts as a good anti-aliasing filter to support down-conversion by sub-sampling. The RF front end employs current reuse for amplification, mixing and filtering. A low phase noise BAW based DCO is used as the reference clock for channel selection and sub-sampling. The front end is integrated in 0.18 μm CMOS process and it exhibits up to 300 kHz bandwidth filtering at RF with 44.2 dB conversion gain and 62 dB rejection at 10 MHz offset from the center frequency.