Design And Research On The Carrier Technology Of Single Carrier UWB Wireless Communication System

UWB radio is a promising candidate for wireless communication, it makes a great progress in the field of wireless communications. For the advantages of high-throughput, the extremely low power spectral density, low probability of detection and intercept, excellent immunity to interference and fine time resolution. Therefore UWB technology has widely application prospect. And it becomes more and more attractive for ranging, radar, imaging systems, communications and so on.In the first section of this paper, firstly the development history, technology characteristics, present status of UWB technology and the work of standardization are introduced. Secondly the performance of system and realistic key technologies of system are analyzed. Finally, three modulation methods and two common multi-access pulse signal models are researched in detail.In the second section of this paper, firstly the signal and system types of Impulse Radio UWB (IR-UWB) and Single Carrier UWB (SC-UWB) had been compared. Then, based on the analysis of the IEEE 802.15.3a UWB indoor channel model, the IR-UWB and SC-UWB signal transmission character are presented. Through compare the Power Spectrum Density of PPM with carrier-less or single carrier, get the infection of carrier to PPM UWB signal.In the third section of this paper, firstly analyze the theory of Negative Resistance oscillator, and a low-phase-noise 2.3GHz negative resistance oscillator is presented. Secondly using the oscillator, a Quenching Oscillator and Fast Switching circuit are presented,at last the results of circuit testing and two kind circuits performance comparing are presented.Quenching oscillator transmitter can operate at extremely high data rates with pulse repetition frequency is 310MHz.The circuit proposed has proven to be very robust and repeatable. The simplicity, low cost, and good performance of this circuit makes it available for UWB system.