An Energy-Efficient Ultra-Wideband Transmitter with an FIR Pulse-Shaping Filter

An energy-efficient impulse-radio ultra-wideband (IR-UWB) transmitter (TX) operating at the sub-GHz range is reported. The IR-UWB TX is composed of a phase-locked loop, a digital modulation circuit, and an FIR-filter-based pulse generator. By utilizing a 4-tap FIR filter for pulse shaping, the output transmission spectrum is spectrally efficient. The maximum pulse repetition frequency of the proposed TX achieves 50 Mpulses/s. The TX operates from a 1-V supply voltage and consumes only 1.5 mW at 50-Mbps data rate. It achieves an energy efficiency of 30 pJ/bit. The TX is fabricated in a 0.18-m CMOS technology and the core area is 0.25 mm 2. © 2012 IEEE.