Study On Multiple User Detection Technology In UWB Wireless Communication System

Impulse radio (IR) and especially time-hopping IR (TH-IR) systems have abstracted considerable attention since their instruction in the context of ultra wideband (UWB) systems in the 1990s. IR systems transmit a number of ultra-short (<1ns) pulses which yield the ultra-wide band on the order of GHz for each information bit. Therefore, UWB IR systems could deliver high data rate in multiple access communications channel just with very simple transmitter and receiver design. Recently, with the U.S. Federal Communication Commission (FCC) actions allowing for the wide-spread use of UWB systems, UWB radio systems will be promising.The central content of this thesis is the Multiple User Detection (MUD) technology in the UWB systems. The MUD technology is one of key technologies in the CDMA systems. The MUD technology is excellently immune to Multiple Access Interference (MAI) and good at near-far resistance, even enhances the performance and capacity of the systems. Theoretically from the performance and complexity, this thesis does some comparing research during several MUD algorithms in TH-IR systems, and compare theirs bit error rate (BER) by computer simulation. At the same time, it is demonstrated that many MUD algorithms developed primarily for DS-CDMA systems can be user essentially without any change in the TH-IR systems. Further, several low-complexity MUD algorithms that exploited the special signal structure used for transmission by TH-IR systems are developed.