Turbo Multiuser Detection: Analysis, Optimization and Applications

目标与意义：turbo原理[27]，即利用软信息在di之间迭代交换的策略。在通信接收器中的事件块，已经成长为一个强大的工具，在攻击各种各样的通信问题。特别是，turbo多用户检测（MUD）范式[59]作为一种新技术引起了人们的广泛关注。多用户通信系统联合译码的有效技术。然而，迄今为止，各种turbo MUD方案的性能主要通过仿真来证明，并且turbo MUD对网络性能（例如吞吐量和延迟）的影响尚未被系统地探索。目前还不清楚上层功能（如ARQ协议，电源控制和准入控制）应该如何设计以利用物理层涡轮MUD。该项目的目标是开发分析工具来评估和优化各种turbo MUD方法的性能，并将这些结果应用于无线网络的跨层设计。最近，一种被称为密度进化的技术[66,67]在编码界得到了发展，它允许对in的迭代解码算法进行分析。nite-length密语。在本提案中，在密度演化框架下，我们概述了一个研究计划，旨在了解针对各种信道条件和接收器结构的涡轮多用户检测的设计和分析，以及考虑到物理层涡轮MUD的一些上层功能的设计。虽然本研究的重点是多用户CDMA系统，但一般原理适用于若干系统，如空时编码系统、OFDM系统和码间干扰系统。

Wang, XiaodongColumbia UniversityObjectives and Significance: The turbo principle [27 ],namely,the strategy that exploits the iteratedexchange of soft information between di .erent blocks in a communication receiver,has grown to be a powerfultool in attacking a diverse set of problems in communications.In particular,the turbo multiuser detection(MUD)paradigm [59 ]has attracted signi .cant recent attention as an e .ective technique for joint decodingin multiuser communication systems.However to date the performance of various turbo MUD schemesis largely demonstrated via simulations,and the impact of turbo MUD on the network performance (e.g.,throughput and delay)has not been explored systematically.It also remains unclear at this time how theupper-layer functionalities (such as ARQ protocol,power control,and admission control)should be designedto exploit the physical-layer turbo MUD.The objective of the proposed project is to develop analytical tools toassess and optimize the performance of various turbo MUD methods,and to apply these esults to c oss-layerdesign in wireless networks.Recently a technique known as density evolution [66,67 ]has been developed in the coding community thatpermits analysis of iterative decoding algorithm for in .nite-length codewords.In this proposal,under thedensity evolution framework,we outline a research plan aimed at understanding of the design and analysis ofturbo multiuser detection for a variety of channel conditions and receiver structures,and the design of someupper-layer functionalities which takes into account the physical layer turbo MUD.While in this study wefocus on multiuser CDMA systems,the general principle is applicable to several systems,such as space-timecoding systems,OFDM systems,and intersymbol interference systems.