跳頻擴時碼介紹
採用改進素數碼的異步跳頻擴時光碼分多址系統的理論分析
馬文華 左超 林金桐
跳頻擴時碼摘要
通過對改進素數碼的不同脈衝位置賦予不同的頻率，提出了一種新的跳頻擴時碼.理論分析表明，此跳頻碼的個數為p3，且有很好的自相關和互相關特性.數值結果也表明在使用雙限幅器的前提下，這種跳頻擴時碼的異步光碼分多址系統有良好的性能.給出了針對這種跳頻碼的編解碼器方案.
關鍵字：光碼分多址； 跳頻碼； 改進素數碼； 雙限幅器
分類號：TN929.11 文獻標識碼：A
文章編號：1007-5321(2001)01-0001-05
The Analysis on Asynchronous Frequency-Time Spreading OCDMA System with Modified Prime Code
MA Wen-hua（Telecommunication Engineering School, Beijing University of Posts and Telecommunications, Beijing 100876, China）
ZUO Chao（Telecommunication Engineering School, Beijing University of Posts and Telecommunications, Beijing 100876, China）
LIN Jin-tong（Telecommunication Engineering School, Beijing University of Posts and Telecommunications, Beijing 100876, China）
Abstract：A novel frequency-time spreading code by designating the different frequencies to the different mark positions of the modified prime code is proposed.Theoretical analysis demonstrates that the number of the proposed codes can amount fo p3.Cross-correlation and the sidelobe of auto-correlation of the proposed code have relatively lower values.The numerical results show that the asynchronous OCDMA system assuming the proposed code reveal excellent performance in the presence of double hard limiters.
Keywords：OCDMA； frequency hopping code； modified prime code； double hard limiters
作者簡介：馬文華(1975—)，男，河南三門峽市人，博士生.
作者單位：馬文華（北京郵電大學電信工程學院， 北京 100876）
左超（北京郵電大學電信工程學院， 北京 100876）
林金桐（北京郵電大學電信工程學院， 北京 100876）
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