This paper presents an integrated circuit transceiver suitable for low data-rate wireless telemetry and sensor networks operating between 135 MHz and 955 MHz implemented in 0.25 /spl mu/m CMOS. Both FSK and Gaussian FSK , as well as ASK and OOK modulation formats are supported at data rates from 150 bps to 200 kb/s. The transceiver's analog building blocks include a low-noise amplifier (LNA), quadrature mixer, baseband filter, received signal-strength indication (RSSI), PLL synthesizer, voltage controlled oscillator (VCO) and power amplifier (PA). FSK demodulation is implemented using a novel digital complex-frequency correlator (CFC) that operates over a wide modulation index range and approximates matched filter detection performance. Automatic gain control (AGC), automatic frequency control (AFC) and symbol timing recovery loops are included on chip. Operating in the 915 MHz band in FSK-mode at 9.6 kb/s, the receiver consumes 19.7 mA from a 3 V supply and achieves a sensitivity of -112-8 dBm at 0.1% BER. The transmitter consumes 28 mA for an output power of 10 dBm and can deliver up to 14 dBm.