混和式跳時直序多重存取超寬頻系統結合N階雙正交脈波位置波形調變之精確性能分析

An Accurate Performance Evaluation of N-ary Bi-orthogonal PPSM for Hybrid TH/DS Multiple Access UWB System

高維民(Wen-Min Kao)

指導教授 ： 沈義順

國立虎尾科技大學/工程學院/航空與電子科技研究所/碩士(2011年)

摘要

此篇論文提出混合式跳時直接序列(TH/DS)多重存取超寬頻系統結合雙正交脈波位置波形調變(BPPSM)，並且對提出的系統作精確性能分析研究。
此TH/DS系統的目的是為了增加傳輸速率和系統容量，且使用TH/DS技術來改善在多重存取超寬頻系統的系統性能。N階雙正交脈衝位置波形調變是結合了脈波位置調變(PPM)、脈波振幅調變(PAM)和脈波波形調變(PSM)用來提升調變階數(N)。此TH/DS系統使用特徵方程式(CF)技術分析，並推導出多重存取干擾(MAI)的機率分佈和TH/DS系統的平均符元錯誤機率(SER)。藉由模擬結果可以驗證理論分析，而TH/DS系統的模擬通道分別選擇是附加白高斯雜訊(AWGN)和實際超寬頻衰減通道(CM1、CM3)。
為了使數值分析和模擬結果能夠公平的比較，所以我們在一些部分比較中固定訊號頻寬(Tp=0.7ns )和固定資料傳輸速率(Tb/Tp=32)。從數值分析和模擬結果我們可以知道，當其他系統參數固定時，藉由增加訊框個數(Ns)，系統的性能可以獲得改善。隨著使用者的數量(Nu)增加，系統性能也隨著衰減。從各種模擬結果可以驗證數學理論分析是精確的。在BPPSM調變系統參數中，所使用的脈波位置個數(M)增加，系統性能是沒有明顯的改善，若所採用之脈波波形(Q)個數增加，系統性能可以獲得明顯改善。

關鍵字

跳時直接序列 ； 脈波位置調變 ； 脈波振幅調變 ； 脈波波形調變 ； 特徵方程式

並列摘要

In this thesis, a hybrid TH/DS multiple access UWB system using the N-ary Bi-orthogonal PPSM is proposed and an accurate performance analysis of this system is provided. The advantage of the proposed system is to increase the transmission rate and the system capacity, and also improve the system performance in terms of using TH/DS multiple access technology. The N-ary BPPSM is a combination of pulse position modulation, pulse amplitude modulation and pulse shape modulation in which the modulation level of the N-ary Bi-orthogonal PPSM can be increased. Based on the characteristic function analytical method, we derive the probability distribution of multiple access interference and the system average symbol error rate. The simulations used to verify the analytical results are carried out in AWGN and actual UWB fading channel.
In order to numerical analysis and simulation results can be a fair comparison, we compare in some parts fixed signal bandwidth and data transmission rate. From the numerical analysis and simulation results, we can conclude when other system parameters are fixed that the performance of the system is improved by increasing the number of frames. As the number of users increase, the system performance degrades more. The theoretical analysis of the proposed system can be verified from the simulation results. Considering the parameters in BPPSM modulation, the SER performance can not be improved significantly when the number of pulse positions is increased. However, the system performance can be improved obviously as the number of the pulse shapes is increased.

並列關鍵字

TH/DS ； PPM ； PAM ； PSM ； CF

參考文獻

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