by Deqiang Chen In a wireless network, users can relay information to exploit cooperative diversity, thereby increasing reliability and reducing power consumption. This thesis focuses on noncoherent communication theory for cooperative diversity. This thesis develops a general framework for maximum likelihood (ML) demod-ulation for cooperative diversity with a decode-and-forward protocol at the...

Limits and Capabilities of Cooperative Diversity: A Network and Protocol Perspective

In this paper, we propose a new relaying protocol for large multihop networks combining the concepts of cooperative diversity and opportunistic relaying. The cooperative relaying protocol is based on two diversity mechanisms, incremental redundancy combining and repetition combining. We assume that nodes in the large multihop network are modeled by a homogeneous Poisson Point Process and operat...

Spectrum sensing is a key technology in the study of cognitive radios, but its attributes are easily influenced by the channel fading. Compared with singleuser spectrum sensing, multiple-user spectrum sensing can overcome the impacts caused by the fading environment of cognitive radio. Since diversity technology has been proved to provide the system high transmission rate and high link reliabil...

Cooperative diversity entails the simultaneous transmission ofinformation by multiple nodes that are in the proximity of each other; this process emulates the functionality of an antenna array. The use of cooperative communications can help combat interference and fading and hence, significantly improve the reliability of the wireless channel without the physical deployment of cumbersome antenn...

Diversity is of particular advantage for wireless personal area networks (WPANs) operating in unlicensed bands, as it may help to overcome not only channel fades but also cochannel interference. We consider WPANs based on time-division multiple access schemes leaving room for cooperative amplitude-and-forward procedures. A formula for the diversity order is presented assuming optimal combining ...

Network coding and cooperative communication have received considerable attention from the research community recently in order to mitigate the adverse effects of fading in wireless transmissions and at the same time to achieve high throughput and better spectral efficiency. In this work, we analyze a network coding scheme for a cooperative communication setup with multiple sources and destinat...

Cooperative diversity has been proposed as an approach to improve the reliability of multihop networks in challenging environments where radio nodes may be disadvantaged due to shadowing. Nodes cooperate by relaying messages, which provides spatial and temporal diversity and may improve network performance in terms of latency and throughput rate. However, additional resources are required to ac...