Low-power radio-frequency ICs for portable communications

The contributions of integrated circuits to the RF front-end of wireless receivers and transmitters operating in broadcast and personal communications bands are surveyed. It is seen from this that when ICs enable a rethinking of the RF architecture, the wireless device can sometimes become significantly smaller, and consume much less power. Examples are taken from FM broadcast receivers, pagers, and cellular telephone handsets. Many semiconductor technologies are competing today to supply RF-ICs to cellular telephones. The various design styles and levels of integration are compared, with the conclusion that single-chip silicon transceivers, combined with architectures which substantially reduce off-chip passive components, will likely dominate digital cellular telephones in the near future. The survey also projects future trends for ICs for miniature spread-spectrum transceivers offering robust operation in the crowded spectrum. With sophistication in baseband digital signal processing, its increasing interaction with the RF sections, and with increasing experience in simplified radio architectures, all-CMOS radios appear promising in the 900 MHz to 2 GHz bands. A specific CMOS spread-spectrum transceiver project underway at the author's institution is discussed by way of example. >