UWB无线通信系统多址技术研究-通信与信息系统专业毕业论文.docx

哈尔滨工程大学硕士学位论文
摘 要
超宽带技术无论是在美国还是欧洲,都得到了极大的关注。超宽带系统利用极短的脉冲(<lns)来产生GHz级的带宽和十分低的功率谱密度。超宽带系统由于其低功耗、低截获率和抗多径衰落效益好的特点,特别适合应用在短距离无线通信领域中。超宽带系统的成功,很大程度上依赖于有效的多址技术的发展。多址技术的主要研究目的是为了解决如何让更多的用户能够共享给定的有限频谱资源的问题。其基本思想是通过合理的分配和利用给定的频谱资源,获得最大的系统容量。
本文的主要研究内容是超宽带系统中的多址技术。本文通过计算机仿真的方法,比较了TH—UWB和DS—UWB两种多址方式的多址性能,得出DS—UWB 无论是用户容量还是误比特率都要优于TH-UWB。然后主要介绍了使用伪混沌编码和使用多级跳频多址技术实现多址的原理,并且在研究多级跳频多址技术时,通过计算机仿真的方法,比较了三种检测接收方法的系统误比特率性能,并提出了优化方法。
关键词:超宽带;多址技术;TH—UWB;DS—UWB;伪混沌编码:多级跳频
哈尔滨工程大学硕士学位论文
ABSTRACT
Ultra-wide band(UWB)systems have received wide attention both in the . and in systems make use of ultra-shott duration r<l ns)pulses which yield a bandwidth on the order of gigahertz signals characterized by extremely low power spectral systems are particularly promising
for short-range munications as they bine plexity with low power consumption,low probability of intercept(LPI)and immunity to multi—path essful deployment of the UWB
technology d印ends strongly on the development of the efficient multiple—access (MA) major purpose of investigating the MA techniques is to resolve how to make more people to share the finite frequency basic poses of making the capabilities of systems the largest by
reasonably assigning and employing some frequency resources.
The MA techniques of UWB are our the performance between the TH-UWB scheme and the DS—UWB scheme by simulation,and the results show that the DS-·UWB scheme is better than TH--UWB both in capability and in Bit Error Rate( we introduce another two methods to implement MA using pseudo-chaotic time hopping multiple access(MA-PCTH) and multistage frequency hopping multiple access(MS/UWB FHMA),and emphasize their we investigate the MS,UWB FHMA,pare the BER in three detection algorithms by simulation,and give the optimized method.
Key words:Ultra—wide band,multiple access,TH—UWB,DS—UWB
pseudo-chaotic time hopping,multistage frequency h