Non-orthogonal random waveform based multiuser communications

This thesis is aimed at providing a unified treatment of non-orthogonal random waveform based multiuser communications, commencing from the underlying theory and providing the way to sophisticated applications. In Chapter 2, we introduce the general framework of non-orthogonal random waveform based multiuser communications, where we focus our attention on the fundamental theory behind this topic. We then pay particular attention to three general application aspects, where the principle of non-orthogonal random waveform based multiuser communications may be exploited. These are applied to cellular systems in Chapter 3, to cooperative systems in Chapter 4 and they are combined with a practical Hybrid Automatic Repeat reQuest (HARQ) system in Chapter 5.<br/>In the cellular system scenario presented in Chapter 3, we discuss three design tradeoffs ofMulti-Carrier Interleave Division Multiple Access (MC-IDMA) with the aid of EXtrinsic InformationTransfer (EXIT) charts. Based on the analysis of IDMA, we generalise the principle of nonorthogonal random waveform based multiuser communications, leading to the so-called Interleaved Random Code Division Multiple Access (IR-CDMA) concept. We also consider an interference-limited cooperative system in Chapter 4, where we propose a novel Interleaved Random Space Time Code (IR-STC) scheme, which is specifically designed for aMulti-Source Cooperation (MSC) scenario. Furthermore, the network coding concept is also employed, when designing a coded MSC arrangement for the sake of improving the attainable energy efficiency. More specifically, the proposed Physical-layer Algebraic Network Coding (PANC) scheme implicitly inherits the random coding principle applied in a distributed manner. In Chapter 5, we proceed by proposing a novel SuperPosition Coding (SPC) aided multiplexed HARQ scheme for substantially improving the overall end-to-end transmission efficiency.<br/>In parallel to presenting our general framework of non-orthogonal random waveform based multiuser communications, we bear in mind that employing a powerful Multi-User Detector (MUD) for maintaining a near-single-user performance is of high importance. Hence, in Chapter 6 we propose a novel so-called Harmony Search (HS) algorithm for joint iterative channel estimation, data detection and channel decoding. The algorithm proposed can be readily employed to replace all detection algorithms used throughout Chapters 3 to 5, when a high throughput is desired.

Name dc:type.qualificationname

Ph.D.

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of Southampton

Year dc:date.issued

2009

Author dc:creator

• Zhang, Rong

Advisor dc:contributor.advisor

• Hanzo, Lajos