14.8 A Fully Integrated 62-to-69GHz Crystal-Less Transceiver with 12 Channels Tuned by a Transmission-Line- Referenced FLL in 0.13µm BiCMOS

The progress towards smaller Wireless Sensor Networks (WSNs) has expanded the applications for ubiquitous sensing. However, the form-factor of a WSN is typically limited by bulky off-chip components, mainly the crystal reference and antenna. Recent work has focused on removing the crystal by recovering the reference from a received RF signal [1], replacing the crystal with an external FBAR resonator [2], using an open-loop oscillator and compensating frequency drift at the gateway [3], or using an on-chip patch antenna for a reference [4]. This paper presents a fully integrated crystal-less TRX that supports node-to-node communication across 12 channels using an integrated transmission line as a reference to lock and tune the RF frequency. The integrated 3-port slot antenna supports TX and RX modes without a TRX switch. The on-off keyed (OOK)-based uncertain IF TRX architecture enables node-to-node communication with 16dB channel selectivity, with no external components required. The chip area is minimized by reusing the active area underneath the passive devices for baseband circuits.