With the growth in demand for personal communication,Wireless Personal Area Network(WPAN) has received more and more attention.It is composed of personal wireless devices which work in Ad Hoc mode,providing reliable and fast transmission of data.On the other ralph lauren polo shirts hand,short-distance wideband wireless access technology has fast developed.Ultra-Wideband technology has been accepted by the WPAN for its wide band,high data transmission,low power and low cost.WPAN based on UWB will satisfy people's need to transfer super-high rate cheap wedding gown dresses data.The design of wireless media access control(MAC) directly affects the network performance in wireless network.An Effective Scheduling Algorithm is needed to improve the custom made prom dresses performance of network.As a consequence,people pay more attention to the research of MAC designed for WPAN based on UWB.This thesis focuses on the wireless MAC in sell discount wedding dresses WPAN based on UWB.The main research contents of this dissertation are recapitulated as follows:(1) Basic knowledge of UWB technology and WPAN is introduced firstly, including development history of UWB,research situation and development trend, and three realization schemes in physical layer.Furthermore,the wedding gowns dresses MAC principles for UWB are analyzed.(2) The IEEE 802.15.3 MAC which is considered as one of the most suitable protocol for use in UWB network is studied in detail.The standard of IEEE 802.15.3 has been defined for the high-rate WPAN.The PHY and MAC protocol are specified in the standard,but the scheduler scheme is undetermined.The IEEE 802.15.3 MAC specification is described and its discount wedding gowns content contains the structure of super-frame, channel access protocol and the communication procedure between devices,and so on.(3) The algorithm of IEEE 802.15.3 which was suggested by Mustafa Demirhan is studied,and the key research is focused on the four kinds of resource scheduling algorithm.These resource scheduling algorithms are used in UWB system.Moreover,the system simulation results taken by the tool of Network Simulation NS2 show that resource scheduling algorithm has great influence on the performance of network.And the results also verify that the SRPT algorithm has better features in throughput,time delay and bit error rate.(4) This thesis studies on the adaptive coded modulation(ACM) technology in the end.And the result from simulation tool NS2 shows that a rate-adaptive MAC protocol has better performance.
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