Two-way中繼系統的中繼選擇算法分析

徐鵬飛,郝　斌,郭鳴霄

(蘭州交通大學 電子與信息工程學院,甘肅 蘭州　730070)

?

Two-way中繼系統的中繼選擇算法分析

徐鵬飛,郝斌,郭鳴霄

(蘭州交通大學 電子與信息工程學院,甘肅 蘭州730070)

摘要為了提升雙向AF中繼系統總速率和降低系統中斷概率,提出了一種最小中斷概率的中繼算法MOP,介紹了現有的兩種中繼選擇算法,利用通信系統的性能指標(信噪比、中斷概率、信道容量)展開分析。仿真結果表明,所提出最小中斷概率中繼選擇算法可明顯降低系統中斷概率,在提升系統總速率的性能與最大化容量中繼算法接近,有效地改善了系統性能。

關鍵詞雙向AF中繼系統;中繼選擇算法;信噪比;最小中斷概率MOP

Analysis of Relay Selection Algorithm in Two-way Relay System

XU Pengfei,HAO Bin,GUO Mingxiao

(College of Electronic and Information Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

AbstractIn order to enhance the total rate bidirectional AF (Amplify and forward) relay system and reduce system outage probability,this paper proposes a minimum outage probability relay algorithm MOP (minimum outage probability),and describes the existing two relay selection algorithms with an analysis of the performance indices (signal to noise ratio,outage probability,and channel capacity) of the communication system.The simulation results show that the proposed minimum outage probability relay selection algorithm can significantly reduce the system outage probability with the performance of improve total rate of the system close to that of the maximum capacity relay algorithm.

Keywordstwo-way AF relay system;relay selection algorithm;SNR;minimum outage probability

在無線通信網絡環境中,協作中繼可使在特定區域內僅有單根天線的中繼設備或移動終端形成一種虛擬天線陣,獲得空間分集增益,這樣不僅提高網絡系統的服務質量和吞吐量,而且強化了覆蓋范圍。單向(One-way)中繼協作系統在雙方信息交互過程中,由于其工作在半雙工模式,使得完成信息交換需要占用4個時隙,這樣便降低了頻譜效率。Rankov和Wittneben提出一種雙向(Two-way)協作策略,信息交換只占用兩個時隙來完成,并推導了在雙向協作模式下放大轉發AF(Amplify and Forward)和解碼轉發DF(Decode and For-ward)的容量值[1],而放大轉發AF是較早采用的一種協同傳輸模式,中繼不對接收信號進行解調或是解碼處理,而是將收到的信號直接放大處理后前傳,這種方式具有低復雜度和易實現的特點。據文獻[2]描述雙向中繼系統的系統容量約是單向協作系統的2倍。……