Impulse Ultra-wideband Communication System Theory And Its Multi-site Study

Ultra-Wide Band(UWB) is a technology that has been drawn considerable attention from both the research institution and industry recently, many companies and colleges also conceintrate on this technology. UWB technology has the features of device simpless, lower transmission power, higher gain and data rate, multipath resolution capability. It can be deployed for military communications. This paper mainly discusses the key points in no-carrier UWB communication system design, these can be concludes as follows:The pulse design is one of the most special and important parts in the no-carrier UWB communication system. This paper bring forward a mixed waveform design method based on the research of seval different pulse waveform, this method can meet the spectrum requirement to the UWB communication system. Therrfore, this design is suitable for using in the UWB system.In the UWB communication system, to enhance the system ability, spread spectrum process is necessary. So in the UWB system design, the code division multiple access(CDMA). The simulation result shows that through the modulation, the system performance becomes better.This paper bring forward a new modulation method based on the research of the traditional modulation method. The new modulation method unites the traditional the pulse amplitude modulation (PAM) and pulse position modulation (PPM), compare to the traditional modulation method, since the system is added the concatenation idea, the new method can improve the system capacity, security, and just add a little in the system complexity. According to the simulation results, the power spectral density of the new method is lower than the traditional method, thereby the system's concealment ability is improved.