Wireless Cooperative Communication Network Research Articles

Retracted: Communication Audio and Video Coding and Decoding Methods in Wireless Cooperative Communication Network

Retracted: Communication Audio and Video Coding and Decoding Methods in Wireless Cooperative Communication Network

Communication Audio and Video Coding and Decoding Methods in Wireless Cooperative Communication Network

Wireless communication is ubiquitous in people’s daily life. As people’s requirements for wireless communication continue to increase, how to improve system performance has become a core issue that communication researchers pay attention to. Wireless cooperative communication is considered to be a key technology in the future communication system because it can provide better communication quality, higher system capacity, wider communication coverage, richer services, and high spectrum utilization efficiency. The proposed network coding can effectively eliminate the transmission bottleneck problem faced by wireless cooperative communication. The development of audio and video communication coding technology has increased the demand for audio and video communication services. The goal of audio and video coding is shifting from traditional storage applications to network transmission. Therefore, the audio and video coding technology for network transmission is being affected by academia and industry. The purpose of this paper is to study the communication audio and video codec methods in wireless cooperative communication networks and to understand the development status of audio and video codec by reading a large number of related documents. On the basis of the problem, relevant experiments are designed to conduct in-depth research. Experimental results show that this scheme can simplify the implementation of scalable coding, improve the coding efficiency of the enhancement layer, and improve the quality of the reconstructed video when the audio and video streams are truncated.

Improved Bi-Directional Three-Phase Single-Relay Selection Technique for Cooperative Wireless Communications

Single-relay selection techniques based on the max-min criterion can achieve the highest bit error rate (BER) performance with full diversity gain as compared to the state-of-the-art single-relay selection techniques. Therefore, in this work, we propose a modified max-min criterion by considering the differences among the close value channels of all relays while selecting the best relay node. The proposed criterion not only enjoys full diversity gain but also offers a significant improvement in the achievable coding gain as compared to the conventional one. Basically, in this article, an improved bi-directional three-phase single-relay selection technique using the decode-and-forward protocol for wireless cooperative communication networks that enhances the overall network performance in terms of BER is proposed and its performance is proved analytically and through Monte-Carlo simulations. More specifically, the proposed criterion is first used to select the best relay-node. After that the selected relay-node forwards the information symbols of the communicating terminals after performing a digital network coding to minimize power consumptions. In our simulations, we show that our proposed technique outperforms the best-known single relay selection techniques. Furthermore, we prove that the BER results obtained from our conducted simulations perfectly match those obtained from the theoretical analysis.

Selection Combiner in Time-Varying Amplify Forward Cooperative Communication

This research presents the diversity combining schemes for Multiple Symbol Double Differential Sphere Detection (MSDDSD) in a time-varying amplify-and-forward wireless cooperative communication network. Four diversity combiners, including direct combiner, Maximal Ratio Combiner (MRC), semi MRC and Selection Combiner (SC) are demonstrated and explained in details. A comprehensive error probability and outage probability performance analysis are carried through the flat fading Rayleigh environment for semi MRC and SC. Specifically, error performance analysis is obtained using the PDF for SC detectors. Finally, power allocation expression based on error performance minimization approach is presented for the proposed SC performance optimization. It is observed that the performance analysis matches well with the simulation results. Furthermore, the proposed SC scheme offers better performance among the conventional MRC and direct combiner schemes in the presence of frequency offsets.

Bit error rate performance analysis of AC-MAP in multiple input single output wireless relay network

In this paper, we propose a joint decoding scheme called AC-MAP decoder for multiple input single output (MISO) wireless cooperative communication network that consists of single source, single relay, and single destination. The proposed scheme is based on both Alamouti combining (AC) scheme and maximum a posteriori (MAP) decoder and is used to estimate the data at the destination. The AC-MAP decoder is optimal in the sense that it minimizes the end-to-end bit error rate (BER). In order to analyze performance of the proposed decoder, we derive a closed form expression for the upper bound (UB) on the end-to-end error probability. Distances between system nodes, transmit energy, and channel noise and fading effects are considered in the derivation of the UB. Numerical results show that the closed form UB is very tight and it almost coincides with the exact BER results obtained from simulations. Therefore, we use the derived UB expression to study the effects of the relay position on the BER performance and to find the optimal location of the relay node.