A Fully Integrated Wideband FM Transceiver for Low Data Rate Autonomous Systems

A frequency-agile FM-UWB transceiver (Tx/Rx) with full on-chip calibration aimed at low data rate autonomous wireless sensing applications is described. The subcarrier VCO, 3-phase CCO, and frequency-tripling PA in the transmit path produce a wideband, double-FM output at -10.1 dBm-pk (FCC compliant). A tunable LNA, envelope detector, limiter, and FSK demodulator comprise the receiver. Digitally programmable matching networks at the PA output and LNA input facilitate independent tuning of Tx and Rx across the 3-5 GHz band. An on-chip SAR-FLL controlling 5 DACs (3 I-DACs and 2 C-DACs) performs a full Tx/Rx calibration in less than 2 ms. Designed for continuous operation at 100 kb/s, measured Rx sensitivity is -80.5 dBm (10 ^-3 BER), and average Tx/Rx energy efficiency is 6 nJ/bit. Total dissipation for the 0.9 mm ² IC implemented in 90 nm RF-CMOS is 630 μW in Tx and 580 μW in Rx mode from a 1 V supply.