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The outage probability of a two-way amplify-and-forward relay system over independent and non-identical Nakagami-m fading channels is investigated. The arbitrary transmit powers at transceivers and relay are considered, and a generalized closed-form expression for the outage probability of the system is derived. Finally, numerical simulations are used to verify the tightness of the analytical result.
In cooperative OFDM networks, ordered subcarrier pairing (OSP) at the relay has been shown to improve the average end-to-end capacity evidently. In this paper, the statistical performance evaluations are provide for two-hop OFDM relay link with both amplify-and-forward (AF) and decode-and-forward (DF) protocol. First, closed-form expressions are derived for the probability density function (PDF) of...
Three low-complexity relay-selection strategies, namely, selective amplify and forward (S-AF), selective decode and forward (S-DF), and amplify and forward with partial relay selection (PRS-AF) in a spectrum-sharing scenario are studied. First, we consider a scenario where perfect channel state information (CSI) is available. For these scenarios, the respective asymptotic outage behaviors of the secondary...
In this paper, we investigate a dual-hop decode-and-forward opportunistic relaying scheme where the selected relay chooses to cooperate only if the source-destination channel is of an unacceptable quality. In our study, we derive exact closed-form expression for the outage probability based on the exact statistics of each hop. Furthermore, we perform asymptotic analysis and we deduce the diversity...
Cooperative diversity is a transmission technique, where multiple users pool their resources to form a virtual antenna array that obtain spatial diversity. We evaluate the performance of coded cooperation with multiple relays in Reyleigh fading channels. The closed-form expressions with multiple relays are derived in this work. Our numerical results show that the new coded cooperation method can achieve...
We study the layered transmission of a Gaussian source over multiple relays using superposition coding. First, we analyze the outage probability and performance in terms of average throughput and distortion for decode-and-forward protocols with single layer and superposed two-layer coding. For the superposition coding approach, we consider different power allocations to the base and enhancement layers...
In this paper, we investigate the performance of the multi-input-multi-output (MIMO) relaying scheme, which combines the Alamouti code with fixed decode-and-forward (DF) protocol. Based on the relationship between the overall signal-to-noise ratio (SNR) of the system and that of the weakest hop, the closed-form expressions of outage probability and bit error probability for MPSK are derived. The analysis...
In this paper, we investigate threshold-based dual-hop relaying schemes in conjunction with partial relay selection in terms of outage probability and bit error probability. The best relay chosen by partial relay selection will transmit jointly with the source using either amplify-and-forward (AF) or decode-and-forward (DF) if the received signal-to-noise ratio (SNR) exceeds a given threshold; otherwise,...
In this paper, exact expressions for outage and average capacity are presented for a decode-and-forward protocol with partial relay selection. An independent but not identically distributed Rayleigh fading environment is considered. Numerical and simulated results demonstrate the validity of the analytical results.
This paper presents an novel iterative generalized selection combining (IGSC) for amplify-and-forward (AF) cooperative communications based on error detection and rearranging the SNR of indirect link in decreasing order of magnitude. The destination node decides whether to accept incoming path or not in every time frame to reduce the excessive burden of maximal ratio combining (MRC) with all diversity...
We study the impact of efficient network coding and multiple access techniques in a two-source two-relay one-destination wireless network through the diversity-multiplexing tradeoff (DMT) analysis. We compare the standard relaying protocol without network coding and the protocols using either a binary network coding (BNC) or an appropriately designed non-binary finite-field network coding (FFNC) at...
In this paper, an efficient Decode-and-Forward (DF) relay selection scheme for interference-limited relaying networks is considered. In contrast to previously reported works, we consider multiple interferences which make the conventional relay selection schemes not suitable for interference-limited networks and propose a new relay selection scheme for DF protocol with multiple interferences. Approximate...
In this paper, we investigate the outage performance of decode-and-forward (DF) based opportunistic cooperative communications with channel estimation errors at the receivers under Rayleigh fading channels, in which the effect of the direct link has been explicitly evaluated. To be specific, the exact expression of outage probability has been derived for arbitrary values of signal-to-noise ratio (SNR)...
In this paper, we investigate a dual-hop opportunistic decode-and-forward relaying scheme where the source may or not be able to communicate directly with the destination. We first derive statistics based on exact probability density function (PDF) of each hop. Then, the PDFs are used to determine closed-form outage probability expression for a transmission rate R. Furthermore, we evaluate the asymptotic...
This paper investigates the outage capacity performance for cooperative wireless communication schemes over independent nonidentical Nakagami-m fading channels with arbitrary fading parameters. The network consists of multiple dual-hop nonregenerative relays in addition to a direct path to achieve the cooperative diversity with maximal ratio combining at the destination. Closed form expressions for...
We consider a wireless relay network with with hybrid-automatic retransmission request (HARQ) and Rayleigh fading channels. In this paper, we analyze the outage probability of the multi-relay delay-limited HARQ system with opportunistic relaying scheme in decode-and-forward mode. A simple and distributed relay selection strategy is proposed for multi-relay HARQ channels. Then, we analyze the performance...
In this paper, we analyze the ergodic capacity (per unit bandwidth) and Average symbol error probability (ASEP) of an incremental relaying protocol used in conjunction with opportunistic relaying and consider a non-regenerative wireless relay network with Rayleigh fading channels. We consider a selection combining technique at the destination in order to combine the two signals, one from the direct...
In this paper, a preliminary investigation is carried out on the possible advantages of employing cooperative diversity to support next generation deep space networks envisaged to operate at Ka band. The background idea is to benefit from recent advances in cooperative protocols by relaying downlink signals from the spacecraft through a geostationary satellite to mitigate tropospheric fading. Numerical...
This paper studies the performance limits of two-way relay channel (TWRC) at finite signal-to-noise ratio (SNR) in Rayleigh fading environment. A two-phase decode-and-forward (DF) protocol is considered. We first derive closed-form expressions for both outage probability and diversity-multiplexing tradeoff (DMT). Our results are general and suitable for any time sharing and any rate allocation in...
In cooperative wireless networks, relay selection plays a significant role in the system performance. In this paper, with the presence of interferences, we firstly propose two relay selection protocols according to the forms of the interferences. Then considering that the interference caused by the selected relay has an effect on other transmissions, a threshold based relay selection protocol is proposed...
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