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The paper investigates robust MPR-based broadcasting in a highly dynamic scenario. There are several methods, or combinations of methods, that can be used to increase the robustness of MPR-based flooding. We investigate the use of a reduced HELLO interval, a fading margin or additional MPRs. It is also important to consider the cost of implementing these methods. To investigate which method to choose,...
This letter considers a multiuser peer-to-peer communication network using a number of shared relays for collaborative beamforming and aims to minimize the total transmitted power of the relays whilst satisfying the targets of the signal-to-interference and noise ratios (SINRs) at the destination nodes by optimizing the relaying coefficients with imperfect channel state information (CSI). By deriving...
In this paper we address the problem of two-way communication in multiple peer-to-peer relay networks, with perfectly known channel state information. Herein, multiple terminal transceiver nodes in the network are organized into two groups, and transceivers in each group want to simultaneously conduct bidirectional communications with their respective peers in the other group through the assistance...
This paper uses generalized singular value decomposition (GSVD) to reduce decoding complexity in an amplify-andforward, multiple-input multiple-output, two-way relay channel (TWRC). The key is diagonalization of the effective channels at the source nodes; this formulation also simplifies the optimization problem of designing linear transceivers at each node to maximize the achievable sum rate (ASR)...
We introduce closed-form lower bounds for the performance of multi-hop wireless networks with non-regenerative relays over Rayleigh fading channels in the presence of co-channel interference. The analysis assumes an arbitrary number of independent and identically distributed Rayleigh interferers. Novel closed-form expressions are obtained for the probability density function (PDF) and cumulative distribution...
This paper considers distributed opportunistic scheduling (DOS) with cooperative relaying in wireless ad hoc networks, with a focus on characterizing the desired tradeoff between the probing cost for establishing cooperative relaying and the higher throughput via opportunistic cooperative networking. Specifically, distributed scheduling and probing for cooperative relaying is treated as an optimal...
Incremental relaying (IR) is known to improve the spectral efficiency of cooperative communication by using the destination feedback. In IR, the relay nodes are employed to assist the source transmission only if it is failed. When the relay nodes perform demodulate-and-forward (DmF), all of them are eligible to forward the source information. This is different from decode-and-forward (DF), where only...
We consider the analysis and design of space-time trellis codes (STTCs) for a cooperative relay channel operating in amplify-and- forward (AF) mode assuming the source and destination nodes are equipped with multiple antennas but the relay node has single antenna. We derive a pairwise error probability (PEP) expression for the performance of STTCs in this type of channels. A simple upper- bound on...
In this paper, we introduce an adaptive cooperative system that selects the best relay among the available relay nodes to cooperate with a source node for transmitting the information signal to a destination node if the spectral efficiency can be maximized. This maximization is achieved as long as the average bit error rate is below a target level. The channels are modeled as independent and identically...
Heterogeneous networks utilizing relay nodes with low transmission power becomes an important deployment scenario in 4G cellular standards. It can offer high data rate delivery as well as ubiquitous end-user experience. For such a network, an efficient mobile association and load balancing scheme is critical to achieve high system capacity and satisfactory user experience. In this paper, the main...
Due to the broadcast nature of wireless transmis- sions, overheard signals can be exploited in multi- hop wireless networks so as to improve the network performance. It has been shown that energy accumulation and information accumulation are two main approaches to utilize multiple overheard signals. However, how to jointly accumulate energy and information in multi-hop wireless networks is still unknown...
Relay node (RN) plays a key role in cooperative communications and RN selection may substantially affects the performance gain. In this paper we address the issue of RN selection while taking into account Medium Access Control (MAC) overhead, which is incurred by not only handshake signaling but also frame retransmissions due to transmission error. We use a theoretical model to analyze the cooperation...
This paper analyzes the performance of the Physical Layer Network Coding (PLNC) approach based on Decode-and-Forward (DF) and operating in multipath fading channel. In actual channel affected by multipath fading the DF method has poor performance since the relay node cannot properly perform data decoding. In addition the decoding at the relay requires the knowledge of the channels involved in the...
In this paper, we consider the power allocation problem in a network coded multiuser two-way relaying network, where multiple pairs of users exchange information with the help of a relay node. An auction-based power allocation scheme is proposed to solve the power competition among multiple user pairs. To maximize the utility of the whole pair, each two users in the pair bid as a single player, with...
Relays are used in the current standards to enhance the cell throughput and coverage. Often, the relays are evaluated without considering the overhead involved in providing the relay with the data prior to the transmission. In this paper, we evaluate the system performance by considering the duplexing loss with over- the-air transmission (OTA) for relay with decode and forward as the relaying protocol...
We consider a multiple access relay network where multiple source nodes send independent packets to a common destination with the assistance from a relay node. We assume that the relay node is equipped with multiple antennas and is allowed to choose either spatial multiplexing (SM) or beam forming mode as transmit diversity (TD). We develop an integrated design methodology for MIMO transmission, network...
We show that the performance of relay selection can be improved by employing relays with buffers. Under the idealized assumption that no buffer is full or empty, the best source-relay and the best relay-destination channels can be simultaneously exploited by selecting the corresponding relays for reception and transmission, respectively. The resulting relay selection scheme is referred to as max-max...
In this paper, we investigate joint relay and jammer selection in a two-way relay network with secrecy constraints, in which there are two sources, a cluster of intermediate nodes, and one eavesdropper. Under a decode-and-forward (DF) protocol, the considered two-way relay network implements a complete transmission in three phases. An intermediate node is selected as conventional relay and another...
We consider a multiple-input multiple-output (MIMO) two-way relay network with two N_{T}-antenna (N_{T}\geq2) end nodes and one dedicated N_{R}-antenna (N_{R}>N_{T}) relay node. A physical-layer network coding (PNC) based joint relay antenna selection and zero-forcing (ZF) spatial multiplexing scheme is proposed to support N_{T} streams of bidirectional data exchanging with the help of N_{T} out...
Heterogeneous cellular networks have emerged as a new paradigm in the wireless network to increase cellular capacity and coverage. Future heterogeneous networks will have a mixed deployment of high power and low power nodes. This creates complicated interference scenarios that require more tight resource coordination among neighbouring nodes than in the traditional cellular networks. In this paper...
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