Performance evaluation of decode and forward cooperative diversity systems over nakagami-m fading channels with non-identical interferers

The deficiencies of regular cooperative relaying schemes were the main reason behind the development of Incremental Relaying (IR). Fixed relaying is one of the regular cooperative relaying schemes and it relies on using the relay node to help in transmitting the signal of the source towards the destination despite the channel’s condition. However, adaptive relaying methods allocate the channel resources efficiently; thus, such methods have drawn the attention of researchers in recent years. In this study, we analyze a two-hop Decode-and-Forward (DF) IR system’s performance via Nakagami-m fading channels with the existence of the several L distinguishable interferers placed close to the destination which diminishes the overall performance of the system due to the co-channel interference. Tight formulas for the Bit Error Rate (BER) and the Outage Probability (OP) are drawn. The assumptions are consolidated by numerical calculations

Cooperative routing in wireless ad hoc networks.

Cheung, Man Hon.Thesis (M.Phil.)--Chinese University of Hong Kong, 2007.Includes bibliographical references (leaves 89-94).Abstracts in English and Chinese.Abstract --- p.iAcknowledgement --- p.iiiChapter 1 --- Introduction --- p.1Chapter 1.1 --- Rayleigh Fading Channels --- p.1Chapter 1.2 --- Ultra-Wideband (UWB) Communications --- p.2Chapter 1.2.1 --- Definition --- p.2Chapter 1.2.2 --- Characteristics --- p.3Chapter 1.2.3 --- UWB Signals --- p.4Chapter 1.2.4 --- Applications --- p.5Chapter 1.3 --- Cooperative Communications --- p.7Chapter 1.4 --- Outline of Thesis --- p.7Chapter 2 --- Background Study --- p.9Chapter 2.1 --- Interference-Aware Routing --- p.9Chapter 2.2 --- Routing in UWB Wireless Networks --- p.11Chapter 2.3 --- Cooperative Communications and Routing --- p.12Chapter 3 --- Cooperative Routing in Rayleigh Fading Channel --- p.15Chapter 3.1 --- System Model --- p.16Chapter 3.1.1 --- Transmitted Signal --- p.16Chapter 3.1.2 --- Received Signal and Maximal-Ratio Combining (MRC) --- p.16Chapter 3.1.3 --- Probability of Outage --- p.18Chapter 3.2 --- Cooperation Criteria and Power Distribution --- p.21Chapter 3.2.1 --- Optimal Power Distribution Ratio --- p.21Chapter 3.2.2 --- Near-Optimal Power Distribution Ratio β´ة --- p.21Chapter 3.2.3 --- Cooperation or Not? --- p.23Chapter 3.3 --- Performance Analysis and Evaluation --- p.26Chapter 3.3.1 --- 1D Poisson Random Network --- p.26Chapter 3.3.2 --- 2D Grid Network --- p.28Chapter 3.4 --- Cooperative Routing Algorithm --- p.32Chapter 3.4.1 --- Cooperative Routing Algorithm --- p.33Chapter 3.4.2 --- 2D Random Network --- p.35Chapter 4 --- UWB System Model and BER Expression --- p.37Chapter 4.1 --- Transmit Signal --- p.37Chapter 4.2 --- Channel Model --- p.39Chapter 4.3 --- Received Signal --- p.39Chapter 4.4 --- Rake Receiver with Maximal-Ratio Combining (MRC) --- p.41Chapter 4.5 --- BER in the presence of AWGN & MUI --- p.46Chapter 4.6 --- Rake Receivers --- p.47Chapter 4.7 --- Comparison of Simple Routing Algorithms in ID Network --- p.49Chapter 5 --- Interference-Aware Routing in UWB Wireless Networks --- p.57Chapter 5.1 --- Problem Formulation --- p.57Chapter 5.2 --- Optimal Interference-Aware Routing --- p.58Chapter 5.2.1 --- Link Cost --- p.58Chapter 5.2.2 --- Per-Hop BER Requirement and Scaling Effect --- p.59Chapter 5.2.3 --- Optimal Interference-Aware Routing --- p.61Chapter 5.3 --- Performance Evaluation --- p.64Chapter 6 --- Cooperative Routing in UWB Wireless Networks --- p.69Chapter 6.1 --- Two-Node Cooperative Communication --- p.69Chapter 6.1.1 --- Received Signal for Non-Cooperative Communication --- p.69Chapter 6.1.2 --- Received Signal for Two-Node Cooperative Communication --- p.70Chapter 6.1.3 --- Probability of Error --- p.71Chapter 6.2 --- Problem Formulation --- p.75Chapter 6.3 --- Cooperative Routing Algorithm --- p.77Chapter 6.4 --- Performance Evaluation --- p.80Chapter 7 --- Conclusion and Future Work --- p.85Chapter 7.1 --- Conclusion --- p.85Chapter 7.2 --- Future Work --- p.86Chapter 7.2.1 --- Distributed Algorithm --- p.87Chapter 7.2.2 --- Performance Analysis in Random Networks --- p.87Chapter 7.2.3 --- Cross-Layer Optimization --- p.87Chapter 7.2.4 --- Game Theory --- p.87Chapter 7.2.5 --- Other Variations in Cooperative Schemes --- p.88Bibliography --- p.8

Stochastic geometric analysis in cooperative vehicular networks under Weibull fading

This is the final version. Available from the publisher via the DOI in this record.We study the performance of a cooperative vehicular communication system in a highway traffic scenario, where the locations of co-channel interfering vehicles are modeled by a one-dimensional Poisson point process (PPP). Wireless channel modeling campaigns have shown that the statistical patterns of vehicle-to-vehicle (V2V) channels can often be modeled by the Weibull distribution. Due to the complex characteristics of random fading and interference, system performance analysis is involved. To address this issue, we establish a framework for performance analysis in vehicular networks under Weibull fading and one-dimensional Poisson field of interference, where the Weibull probability density function (PDF) is approximated by a finite exponential mixture. By this means, the approximation expressions of the successful/unsuccessful message transmission probabilities for both direct V2V communication and the three-node cooperative vehicular communication are derived through stochastic geometry. Monte-Carlo simulations verify the accuracy of our derivation, as well as the advantages of encouraging cooperation among vehicles. Our methods and results can potentially be used to facilitate stochastic geometric analysis in many other complex vehicular networks under Weibull fadingEuropean Commissio

Coherent versus non-coherent decode-and-forward relaying aided cooperative space-time shift keying

Motivated by the recent concept of Space-Time Shift Keying (STSK), we propose a novel cooperative STSK family, which is capable of achieving a flexible rate-diversity tradeoff, in the context of cooperative space-time transmissions. More specifically, we first propose a Coherent cooperative STSK (CSTSK) scheme, where each Relay Node (RN) activates Decode-and-Forward (DF) transmissions, depending on the success or failure of Cyclic Redundancy Checking (CRC). We invoke a bitto- STSK mapping rule, where according to the input bits, one of the Q pre-assigned dispersion vectors is activated to implicitly convey log2(Q) bits, which are transmitted in combination with the classic log2(L)-bit modulated symbol. Additionally, we introduce a beneficial dispersion vector design, which enables us to dispense with symbol-level Inter-Relay Synchronization (IRS). Furthermore, the Destination Node (DN) is capable of jointly detecting the signals received from the source-destination and relay-destination links, using a low-complexity single-stream-based Maximum Likelihood (ML) detector, which is an explicit benefit of our Inter-Element Interference (IEI)-free system model. More importantly, as a benefit of its design flexibility, our cooperative CSTSK arrangement enables us to adapt the number of the RNs, the transmission rate as well as the achievable diversity order. Moreover, we also propose a Differentially-encoded cooperative STSK (DSTSK) arrangement, which dispenses with CSI estimation at any of the nodes, while retaining the fundamental benefits of the cooperative CSTSK scheme

Cooperative Diversity for Fading Channels in the Presence of Impulsive Noise

Although there already exists a rich literature on cooperative diversity, current results are mainly restricted to the conventional assumption of additive white Gaussian noise (AWGN). AWGN model realistically represents the thermal noise at the receiver, but ignores the impulsive nature of atmospheric noise, electromagnetic interference, or man-made noise which might be dominant in many practical applications. In this thesis, we investigate the performance of cooperative communication over Rayleigh fading channels in the presence of impulsive noise modeled by Middleton Class A noise. We consider a multi-relay network with amplify-and-forward relaying and orthogonal cooperation protocol. As for the coding across the relays, we employ either space-time coding or repetition coding. For each scheme, we assume various scenarios based on relays’ location and quantify the diversity advantages through the derivation of the pairwise error probability. Based on the minimization of a union bound on the error rate performance, we further propose optimal power allocation schemes and demonstrate significant performance gains over their counterparts with equal power allocation. We finally present an extensive Monte Carlo simulation to confirm our analytical results and corroborate on our results