A PPM Gaussian transmitter for UWB using a compact phase detector

Abstract

This paper presents a design of an UWB PPM — Pulse Position Modulation transmitter based on a 1.8V, 0.18μm CMOS technology. We propose a pulse generator using modified Nand gate as a Phase Detector (PD) with an effective phase difference of 73ps. At the PD output an extra derivative circuitry exists. The whole circuit has been simulated using LTSpice and the results had demonstrated the circuit capability to operate as an impulse generator. The Gaussian impulse achieves a very small pulse width of about 192ps, and amplitude of 44mVpp, with power dissipation of 1μW. The complete circuit occupies area of 220×220 μm2 including the inductor, but without PADS.