A Gated FM-UWB System With Data-Driven Front-End Power Control

This paper presents a frequency modulated ultra-wideband (FM-UWB) transceiver system with RF submodules gated by a data-driven control signal. With the control signal, intermittent operation of key building blocks such as a VCO in the transmitter and a wideband FM demodulator in the receiver is realized. To enable an effective dynamic power control, the transmitter generates higher subcarrier frequency and modulation index than conventional FM-UWB transmitters by utilizing an 8-modulo fractional-N PLL in which a triangular waveform is generated by a relaxation VCO. In the receiver, an envelope detector monitors the presence of incoming signal and enables the data-edge-triggered power control for a wideband FM demodulator and other blocks. A prototype 3.5-4.1 GHz FM-UWB transceiver for on-chip wireline testing is implemented in 0.18-μm CMOS. Experimental results show that the proposed gated FM-UWB system successfully demodulates the FSK information, achieving nearly 53% power saving with the data-driven power control enabled.