Multiband monolithic BiCMOS low-power low-IF WLAN receivers

This letter presents the design, implementation, and measurements of two monolithic low-IF receivers compliant with the main WLAN standards. The first receiver targets the three 5GHz U-NII bands, while the second allows dual-band operation in the 2GHz and 5GHz bands. Fabricated in a 47GHz-f_t BiCMOS technology, both consist of a low-noise preamplifier, two matched active singly-balanced mixers and two polyphase filters, used to generate quadrature LO signals and provide image-rejection. The single-band receiver exhibits 25 dB of conversion gain, 8.9 dB of NF and -19 dBm of P_{1 dB}, while consuming 19 mW. The dual-band receiver shows similar performances in the 5GHz band, and extends its operation in the 2GHz band, achieving 33.4dB of conversion gain, 4.1dB of NF and -26dBm of P_{1 dB}, while consuming 14.9mW.