Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/7396
標題: 多速率跳頻無線通訊系統之設計及效能分析
Design and Performance Analysis for Multi-Rate MFSK/FH-CDMA Wireless Communication Systems
作者: 陳俊傑
Chen, Jun-Jie
關鍵字: Wireless Communication Systems;無線通訊系統;Frequency-Hopping Systems;跳頻通訊系統
出版社: 電機工程學系
摘要: 
在大部分的無線跳頻系統中,通常只能提供單一媒體服務,然而人們期望在未來的無線通訊環境中,對於不同的品質需求能夠提供具有彈性的多媒體服務。在本篇論文中,我們提出一種藉由改變跳頻系統每一個時槽中頻率跳躍數目的方式來達成多速率的目的,而這種達成多速率的方式並不會造成跳頻碼的浪費。此外,我們也對此多速率系統做了分析,從分析的結果來看,我們提出的這種方法的確能有效的應用於無線多媒體服務系統。
除此之外,我們也建構了一種新的跳頻碼,這種跳頻碼的長度為P3,其中P為一個質數,個數為P3-P個,任兩個跳頻碼之間互相關性為4。這P3-P個跳頻碼可以分成P(P+1)組,每一組中有P-1個碼,在同一組中的任兩個跳頻碼的互相關性可以降至1。藉由這樣的特性,我們可以將同一組的跳頻碼先分配給系統中的用戶以得到最佳的效能,因為這樣的跳頻碼具有良好的相關性,所以非常適合應用於未來的無線通訊系統。

Most studies on multilevel frequency-shift keying/frequency-hopping code-division multiple-access (MFSK/FH-CDMA) wireless
systems are assumed to support only one type of medium.
It is expected a flexible support of multi-media services with
different quality requirements in the future wireless systems.
In this thesis, an FH-CDMA technique is proposed to provide multi-rate services by varying the number of hopping frequencies per chip assigned to a user. This new scheme can support the multi-rate services without resulting in the reduction of sequence consumption. The performance of the new multi-media MFSK/FH-CDMA wireless systems is analyzed.
Our results show that the proposed scheme is useful for FH-CDMA
wireless systems with multi-media services. Furthermore, a new construction of FH patterns, which is called generalized concatenated prime codes, has been provided for MFSK/FH-CDMA systems. We have constructed P^3-P FH patterns with
length P^3 and maximum cross-correlation of four.
These P^3-P FH patterns can be partitioned into P(P+1) groups, and the maximum cross-correlation in each group can be reduced to one. For this characteristic, we assign FH patterns in the same group first to the users within the system to gain optimal performance. Owing to the low cross-correlation property, the new designed codes will be useful in future wireless communication systems.
URI: http://hdl.handle.net/11455/7396
Appears in Collections:電機工程學系所

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