Design of 180nm CMOS impulse radio ultra wideband transmitter for biomedical imaging

Abstract

This thesis is about the design of radio-frequency (RF) integrated circuits for Impulse Radio Ultra-Wideband (IR-UWB) transmitter which is a system of ultra-low power pulse shaping methods for achieving low energy per pulse (EPP). The proposed transmitters are composed of all digital single pulse generator, multiple controlled digital delay lines, a pulse combination circuit, and pulse shaping stages with a pulse shaping capacitor and wire-bond inductor at the output. The generated mono pulse width and the consecutive mono pulse positions are determined by the delay lines. The proposed transmitter architectures are designed in 180 nm CMOS technology, and supply voltage is 1.8V. Use of UWB provides more bandwidth that is necessary for high data rates at 2.4 GHz for biomedical applications. The simulation results show that the energy required to generate the Gaussian mono-cycle, triplet, and quintuplet pulses are 29 pJ, 47 pJ, and 65 pJ respectively at 200 MHz pulse repetition frequency without band pass lter (BPF). The required energies utilizing a BPF to generate output signals are 36 pJ, 54 pJ, and 72 pJ respectively. The motivation of the thesis is to generate the Gaussian quintuplet signal with low power consumption and high data rate without using BPF.