Tr-uwb Wireless Communications And Controlling Experimental System And Experimental Research

High-data-rate has become an important part of wireless communications research. Ultra-wideband (UWB) is a promising short range communication technique with high data rate, large system capacity, low transmission power, good interference ability, and simple architecture. It has wide applications in many fields.Time reversal (TR) is an environment adaptive wireless transmission method based on the electromagnetic reciprocity principle. TR possesses a unique property of energy focusing both temporally and spatially. Such a property is capable of turning adverse effects from multipath into benefits. In a complicated multipath environment, the temporal-spatial focusing from TR can significantly compress multipath delay spread, reduce inter-symbol interference, improve the signal to noise ratio, and increase system transmission rate.This paper comprehensively investigates the progress of UWB technology and TR's application in UWB. Based on TR-UWB communication theory, we build an automatic measurement testbed system in software defined radio architecture that can be controlled remotely by using advanced time-domain measurement equipments. In a typical indoor environment, we investigate waveform time reversal UWB (WTR-UWB), channel time reversal UWB (CTR-UWB) and traditional UWB and compare their experimental results. The results show that TR exhibit improved performance in compressing delay spread, improving signal-to-noise, and reducing inter-symbol interference. A high data rate of 500Mbps @4m in the multipath environment is successfully achieved by TR based UWB systems. The thesis includes five chapters:Chapter 1 describes the development of UWB wireless communications including their advantages, challenging and solutions. We brief the temporal and spatial focusing principle of TR and discuss the advantages of TR and its application in UWB wireless communications.Chapter 2 introduces basic principles and key technologies of TR-UWB wireless communications, including TR signal generation, modulation, detection process, as well as two kinds of TR: waveform time reversal (WTR) and channel time reversal (CTR). Chapter 3 presents the design of the automatic measurement testbed for TR-UWB in software defined radio architecture that can be remotely controlled.Chapter 4 compares several TR based UWB systems with traditional UWB systems with full time domain experimental results in multipath-rich indoor environment. The TR based UWB systems include SISO, SIMO, MISO, MIMO.Chapter 5 summarizes the paper followed by the prospective of future research.