Single chip CMOS transmitter for UWB impulse radar application

Abstract

Ultra-Wide Band (UWB) technology has been studied intensively these years. And transmitter plays an important role in the UWB transceiver system since it has the function of generating the UWB impulses which is used to transmit the information through propagation channels. Among the vast applications of UWB technology, UWB radar is a hot spot since it is widely used in the detection of moving object in the field of radar. This thesis presents the design of an on chip transmitter for Ultra-Wideband (UWB) Impulse Radar application. Short pulses with duration of 4.5 ns and bandwidth of about 500 MHz are generated by up-converting the triangular shaped envelope to the center frequency by a specially designed energy efficient mixer. In this UWB Impulse Radar Project, two versions of transmitter test pattern chips were designed, fabricated, and measured. Both versions of the transmitters can work at pulse repetition frequency of over 1 MHz with over -2 dBm output power at 50 ohm load. Output pulse spectrum centered at 4.3 GHz can fit FCC spectrum mask with a side-lobe suppression of 20 dB. Designed in 0.18-$\microm$ CMOS technology, the two circuits have a chip area of 0.45 mm $\times$ 1.2 mm. The details of architecture decision and design process are discussed in this thesis. The improvement of second chip is also analyzed comparing with first version chip.