A Low Power BAW Resonator Based 2.4-GHz Receiver With Bandwidth Tunable Channel Selection Filter at RF

A low power sub-sampling multi-channel 2.4-GHz receiver front-end is presented. Bulk Acoustic Wave (BAW) resonators which intrinsically exhibit high quality factor (Q) are exploited in the frequency synthesis to provide low phase noise signal with low power consumption. A low power solution to perform channel selection and filtering directly at RF by employing current reuse and using a BAW resonator is proposed. The filter is capable of tuning the bandwidth and thus making the front-end to be suitable for multi-band/multi-standard applications. The overall performance of the front-end is improved by additional discrete time filtering which also down-converts the wanted channel to baseband in quadrature. The proposed front-end is designed and integrated in a 0.18-μm CMOS process. Measurements reveal that the front-end is capable of providing very narrow band filtering down to 300 kHz. The rejection at 10-MHz offset is 62 dB with conversion gain of 44.2 dB.