Research On UWB Technology And Its Application In WSN

With the development of wireless communication technology, various kinds of wireless communication systems come forth one after another, which causes the available frequency resource becoming rare. Ultra wide band (UWB) communication is a novel short-distance wireless communication technique,in which data are transferred using impulses with very short duration .It has many advantages,such as high transmission rate,low Power consumption,good security,highly accurate Positioning capability and low cost. With the approval of FCC,there are increasing interests in studying UWB technologies in both academia and industry.According to FCC's definition, the concept of UWB is not limited to pulse transmitting. UWB can be extended to continuous transmitting technology as long as the signal band with is larger than 500MHz. At present, there are three kinds of fulfill schemes of UWB communication system, that is carrier-free pulse scheme, signal carrier DS-CDMA and MB-OFDM. UWB has the traits of: high transmission rate, low Power consumption, ability of accurate orientation. Because of these traits, UWB has become a focus of the research on wireless communications.WSN is a kind of Ad-hoc. Each node has a Distributed algorithm and it id essential to use multi-hop transition. WSN based on UWB, the UWB is Particularly attractive due to its highly accurate Positioning capabilities which can forecast the topology of network, low transmission power which can reduce node's battery power consumption, rate and range changing over , etc in a word ,UWB- WSN will have better network capability and better security capability.Most of the study on UWB-WSN is about MAC protocol and routing protocol based on TOA of UWB. Based on the trait of rate and range changing over, this paper introduces a theory of improved MCDS algorithm. Then, experiment and research the theory. A conclution is drew that: the improved ML-MCDS algorithm is better than the ML algorithm. It increases the communication range of node step by step. It mak the node which is in high power consumption condition exited the CDS. So this improved ML-MCDS algorithm help the networks extending its life. But thecost is the lower communication rate. And the connectivity of the networks is worse. So the improved ML-MCDS has effect on extending the life of WSN. Otherwise, other works are study on MB-TFI-OFDM UWB system based on time hopping and time- frequency crossing. The technology of MB-TFI-OFDM based on time hopping is a kind of advance of OFDM. It makes the UWB system better. MB-TFI-OFDM UWB system will be widely used in the future.Experiment is an effective way of testifying results in theory and a way of promoting principle research. A lot of works are carried out on Matlab platform in this paper. Based on achieved theory, the improved MCDS algorithm is validated.Research achievements in this paper is mainly :Study on the theory of UWB-WSN topology control algorithm; and raise an improved MCDS algorithm.