High-Order Monocycle Design and Its Waveform-Generating Circuit for UWB Communications

Ultra-wide-band (UWB) technology can provide data throughput rate at gigabit per second. UWB also shows promising potentials for use in short-range indoor wireless communications and outdoor ad hoc networking. Adopting ultra-short impulses in UWB transmission, however, make systems vulnerable to timing jitter. To overcome this challenge, we propose a time-hopping high- order waveform modulation scheme in this paper. Central to our design is the adaptation of a high-order monocycle (HOM), which provides timing-jitter robust UWB communications. We present a CMOS pulse generator circuit to produce the HOM monocycle. We also use 0.18-mum CMOS technology with 1.8-V power supply to simulate the monocycle generator design using the Cadence software. The simulation results show that our generated waveform meets the UWB communication and the FCC requirements. Our modulation scheme outperforms other systems using traditional monocycles in terms of timing-jitter robustness.