Research On TR Receiving Technology And Cooperative Spectrum Detection Technology In UWB-CR System

As two kinds of new radio applications, Cognitive radio (CR) technology andUltra-Wideband radio (UWB) technology can ease the shortage of spectrum to acertain extent. In line with the principle of complementary advantages, people putforward a kind of more advantageous spectrum sharing scheme by mixing the CRtechnology and the UWB technology, namely the UWB-CR system. Through thespread use of spectrum, the UWB-CR technology can not only improve theeffectiveness of the spectrum testing, control the level of harmful noise, optimize thepower loss, but also provide a flexible, efficient, and low power wireless application.However, UWB-CR system is still in its concept stage, and along with the confluenceprogress, the noise of the two basic communication systems is becoming a very seriousproblem for the designing and planning of UWB-CR system.Aiming at eliminating the noise’ harmful effect on the system performance, wefocus on the receiving technology and the cooperative spectrum detecting technology.We introduce an improved differential transmission reference (IDTR) which canefficiently weaken the interference noise in chapter four, and propose an improved datascreening algorithm in chapter five, which can enhance the SNRs of the final decisioninformation and lead to the enhancement of the detection probability. And the maincontent includes the following several parts:1As to the receiver type, we choose the differential transmission reference (DTR)receiver as the research focus through relative comparative analysis. Firstly, wecompare the transmission reference (TR) receiver with the rake receiver and draw thefollowing conclusion: the TR receiver has simpler structure and is easier to realize,which is chosen as the primary research object; then we choose the DTR receiver,which is the most eclectic receiver of the three TR-based receivers, as the key pointfor further research.2The reference signal of DTR still has some harmful noise which has a harmfuleffect on the receiving performance, so we propose an IDTR receiver based on DTRreceiver, and the IDTR receiver uses the relevance of signals to remove the harmful noise. Then we carry on the relative simulations which are made of two parts. We cansee that the DTR receiver is really a relatively eclectic receiving technology from thefirst part of the simulation results, which are about the simple TR receiver and theaverage TR receiver. The second part of the simulation results shows that the SNR ofthe received reference signals in IDTR attains1dB enhancement comparing with DTR,and the performance of this system is better than DTR.3We introduce the cooperative spectrum detection system from different angles.Firstly, we classify the relative algorithms into the following three categories: thetraditional algorithm, the spectrum-estimation-based algorithm and the wavelet-basedalgorithm. Then we introduce the cooperative scheme from two aspects. At last, theperformance indexes of the cooperative spectrum detection system are introduced.4For the hidden terminal problem, we develop a cooperative spectrum detectionsystem based on the proposed data screening algorithm, and simulate the comparativeperformance curves of the improved algorithm and another two kinds of detectionalgorithms. The experimental results show that the detection probability isdramatically improved; and the theoretical analysis shows that the real-timeperformance of this system will be enhanced with the development of UWBpositioning technology.