Multiband 0.25-μm CMOS Base Station Chips for Indirect and Direct Conversion Receivers.

This paper describes a multiband CMOS chip-set for indirect and direct conversion base station receivers. The chip set consists of a low-noise amplifier (LNA), and a down-converter which includes a passive resistive mixer and a local-oscillator balun. The 0.25-µm CMOS receiver chip set, biased at 3 V, meets normal DCS1800, PCS1900, and Universal Mobile Telecommunication System (UMTS) base station specifications in heterodyne and homodyne architectures. In a heterodyne architecture, an third-order input intercept point (IIP3) higher than -5 dBm was achieved with a noise figure (NF) lower than 4.5 dB for the complete receiver chain in the DCS1800, PCS1900, and UMTS bands. In a homodyne architecture, IIP3 and second-order input intercept point (IIP2) values better than 0 and 40 dBm, respectively, were achieved for the complete receiver chain in all three bands, with an NF of less than 6 dB. A dedicated DCS1800 heterodyne receiver based on this chip-set was developed, meeting and exceeding the specifications, with a NF of 5.8 dB and IIP3 of 0.4 dBm. This is believed to be the first CMOS receiver chip set that meets second and third-generation base station specifications in indirect and direct conversion architectures. [ABSTRACT FROM AUTHOR]