A dual-band RF transceiver for multistandard WLAN applications

A new dual-band RF transceiver is presented for 2.4- and 5.2-GHz multistandard wireless local area networks. The proposed dual-band RF transceiver integrates a concurrent dual-band front-end, a triple-band frequency synthesizer, and a band-sharing in-phase/quadrature modulator/demodulator to maximize component and power reuse. The design is started with the examination of an enhanced dual-band heterodyne architecture and then the optimal circuit partition to satisfy the multistandard requirements. Key dual-band circuits are designed and integrated with other building blocks for experimental demonstration. The measurement shows that eight 5-GHz channels and 13 2.4-GHz channels can be synthesized within 130 /spl mu/s with phase noise less than -98 dBc/Hz at 100-kHz off carrier and spur suppression greater than -65 dBc. The transmitted P/sub 1 dB/ power is 25/20 dBm at 2.4/5.2 GHz, respectively, with the modulation accuracy error-vector magnitude (EVM) values varying from 3.57% to 7.19%. The receiver gain is 20/31 dB at 2.4/5.2 GHz front-end and 70 dB at IF back-end with EVM within 2.32% to 10% from -70- to -17-dBm received power range.