An all-digital IR-UWB transmitter with a waveform-synthesis pulse generator in 90nm CMOS for high-density brain monitoring

Abstract

This paper reports an all-digital impulse radio ultra wideband transmitter (IR-UWB TX) fabricated in 90-nm CMOS, which incorporates a waveform-synthesis pulse generator and a timing generator for OOK/PPM pulse modulation and scrambling. The UWB pulse generator includes ten identical taps, each comprising an impulse generator and an output driver. Upon triggering by the timing generator, these taps create a programmable number of individual lobes with 4b control over their duration and amplitude, which are then combined at a shared output node to generate the UWB pulse. With a high-performance receiver, the TX might be used for moderate-data-rate (<;50Mbps), m-range telemetry, suitable for brain-behavior studies, with energy consumption in the range of 12 to 20pJ/pulse, and for high-data-rate (>100Mbps), cm-range telemetry, suitable for brain-machine interfaces, with energy consumption in the range of 3.6 to 6pJ/pulse from 1.2V.