Performance Modeling of the Fast and Reliable Two-Layer Retransmission for CDMA Systems  

作　　者：LIUFang KONGJian WANGWen-bo LIUYuan-an 

机构地区：[1]BeijingUniversityofPostsandTelecommunications,Beijing100876,P.R.China

出　　处：《The Journal of China Universities of Posts and Telecommunications》2005年第1期101-106,共6页中国邮电高校学报（英文版）

基　　金：This work is supported by"863"High Technology Development Project Fundation (No.2003AA12331004).

摘　　要：In this paper, an analytical model of two-layer retransmission scheme isproposed for CDMA systems in which selective repeat Automatic Repeat reQuest (ARQ) is used at theRadio Link Protocol (RLP) layer and n-channel Stop-and-Wait hybrid ARQ at the Medium Access control(MAC) layer. The retransmission mechanism in the RLP has considerable amount of delay associatedwith it, which might not be able to sustain real-time communications with strict delay requirements.Retransmissions done at a lower layer, such as the MAC, enhance the performance of the system. Weshow how the joint reliability varies with respect to the maximum retransmission number of RLP layerand MAC layer. We also consider that soft packet combining at the MAC layer of receiver issupported, which effectively lowers the Frame Error Rate (FER). Compared with the RLP Layer ARQ usedin IS-99, the two-layer retransmission scheme shows shorter packet transmission delay and smallerpacket error rate. The results show that it can offer the faster and more reliable communicationthan conventional scheme used in IS-99.In this paper, an analytical model of two-layer retransmission scheme isproposed for CDMA systems in which selective repeat Automatic Repeat reQuest (ARQ) is used at theRadio Link Protocol (RLP) layer and n-channel Stop-and-Wait hybrid ARQ at the Medium Access control(MAC) layer. The retransmission mechanism in the RLP has considerable amount of delay associatedwith it, which might not be able to sustain real-time communications with strict delay requirements.Retransmissions done at a lower layer, such as the MAC, enhance the performance of the system. Weshow how the joint reliability varies with respect to the maximum retransmission number of RLP layerand MAC layer. We also consider that soft packet combining at the MAC layer of receiver issupported, which effectively lowers the Frame Error Rate (FER). Compared with the RLP Layer ARQ usedin IS-99, the two-layer retransmission scheme shows shorter packet transmission delay and smallerpacket error rate. The results show that it can offer the faster and more reliable communicationthan conventional scheme used in IS-99.

关 键 词：TCP ARQ CDMA 

分 类 号：TN929.533[电子电信—通信与信息系统]