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Wireless Communications, IEEE Transactions on

Issue 7 • Date July 2013

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Displaying Results 1 - 25 of 48
  • Table of contents

    Page(s): c1 - c4
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  • Staff list

    Page(s): c2
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  • Analytic Bounds on Data Loss Rates in Mostly-Covered Mobile DTNs

    Page(s): 3121 - 3129
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1112 KB) |  | HTML iconHTML  

    We derive theoretical performance limits of densely covered delay-tolerant networks (DTNs). In the DTN model we study, a number of fixed (data collector) nodes are deployed in the DTN region where mobile (data generator) nodes move freely in the region according to Brownian motion. As it moves, each mobile is assumed to continuously generate and buffer data. When a mobile comes within the communication coverage range of a data collector node, the mobile immediately and completely uploads its buffered data to the data collector node, and then resumes generating and buffering its data. In this paper, we first derive analytic bounds on the amount of time a mobile spends without communication coverage. Then, using these derived bounds, we derive sufficient conditions on node density that statistically guarantee that the expected amount of time spent in the uncovered region remains below a given threshold. Additionally, we derive sufficient conditions on node density to keep the probability of buffer overflow below a given tolerance. View full abstract»

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  • Two-Dimensional ESPRIT-Like Shift-Invariant TOA Estimation Algorithm Using Multi-Band Chirp Signals Robust to Carrier Frequency Offset

    Page(s): 3130 - 3139
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    In this paper, a two-dimensional (2-D) ESPRIT-like shift-invariant time-of-arrival (TOA) estimation (ELSITE) algorithm for multi-band chirp signals in the presence of a carrier frequency offset (CFO) is presented. For the shift invariant TOA estimation, the received signals must be transformed into a sinusoidal form. When the received signals are perturbed by a CFO, the frequency of the transformed sinusoids is also shifted such that the TOA estimation results are biased. The TOA-induced phase shift of the multi-band chirp signals is determined according to the parameters of the signal, while the CFO-induced phase shift is only proportional to the elapsed time. Based on this property, the proposed ELSITE algorithm achieves robust TOA estimation against CFO from the signal subspace of the stacked matrix. The root mean square error of the proposed algorithm was analyzed and verified in both an AWGN channel and a multipath channel with CFO via Monte-Carlo simulations. View full abstract»

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  • Pilot-Aided Side Information Detection in SLM-Based OFDM Systems

    Page(s): 3140 - 3147
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    Selected mapping (SLM) based schemes effectively reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) systems. However, they require side information (SI) transmission, which incurs a loss in the data throughput in addition to the increased system complexity. This paper presents a blind SLM scheme based on a decision metric obtained from pilot sub-channel responses. A novel SI detection method enabling low complexity data decoding is proposed. The SI is detected by exploiting the high autocorrelation between adjacent pilot sub-channel responses. The SI detection error rate is analytically derived and compared with that obtained by simulations. Simulation results of the data decoding scheme based on the proposed SI detection method show the bit error rate performance comparable to that of the simplified maximum likelihood (ML) data decoding scheme, while the computational complexity is close to that of the embedded SI based decoding scheme. View full abstract»

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  • Two-Phase Scheduling and Leakage-Based Precoding in Wireless Cellular Networks

    Page(s): 3148 - 3157
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    We consider the downlink of a wireless cellular network where the base stations are equipped with multiple antennas and operate in the same frequency band. Since scheduling changes the spatial transmit signal processing with each time slot, information from neighboring base stations is required for data encoding. This can, in theory, be accomplished by a high-capacity backhaul network through which the base stations exchange channel state information (CSI) and other control signals. In reality, however, the temporal granularity of the scheduler does not allow for timely distribution of CSI among base stations. We propose a two-phase scheduler which optimizes the precoding in the first phase and allows the users to feed back their instantaneous interference power in the second phase. For the single-user case, we present a practical scheme that combines two-phase scheduling with precoders that maximize the signal-to-leakage-plus-noise ratio. If the users feed back the interference power together with a supported rate, communication between base stations can be limited to integers. By comparing the performance to multi-user two-phase scheduling with dirty paper coding and to algorithms that share CSI among base stations we show that two-phase scheduling is a technically and practically feasible solution to deal with non-stationary intercell interference. View full abstract»

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  • Joint Network-Channel Coding with Rateless Code in Two-Way Relay Systems

    Page(s): 3158 - 3169
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    In this paper, we propose a three-stage rateless coded protocol for a half-duplex time-division two-way relay system, where two terminals send messages to each other through a relay between them. In the protocol, each terminal takes one of the first two stages respectively to encode its message using rateless code and broadcast the result until the relay acknowledges successful decoding. During the third stage, the relay combines and re-encodes both messages with a joint network-channel coding scheme based on rateless coding which provides incremental redundancy. Together with the packets received directly in previous stages, each terminal then retrieves the desired message using an iterative decoder. The degree profiles of the specific rateless codes, i.e., Raptor codes, implemented at both terminals and the relay, are jointly optimized for both the AWGN channel and the Rayleigh block fading channel through solving a set of linear programming problems. Simulation results show that, the system throughput as well as the error rate achieved by the optimized degree profiles always outperforms those achieved by the conventional degree profile optimized for Binary Erasure Channel (BEC) and the previous network coding scheme with rateless codes. View full abstract»

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  • On Transmission of Multiresolution Gaussian Sources over Noisy Relay Networks

    Page(s): 3170 - 3179
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    This paper investigates joint source-channel coding (JSCC) in a decode-and-forward three-node relay network, in which scalable source coding (SSC) is coupled with superposition coding (SPC) to form a layered coding architecture of SSC-SPC. In contrast to any previously reported research using asymptotic capacity-based distortion (CBD) measure, we derive the mean-squared error end-to-end distortion (EED) of such JSCC system based on a real-valued Gaussian source, aiming to achieve better precision and practicality for applications in which channels are subject to large error probabilities. The EED evaluation is formulated and applied to demonstrate achievable gains of the SSC-SPC architecture versus a number of conventional approaches. Power allocation optimization is performed based on the developed non-asymptotic EED model and compared to that by using an asymptotic CBD measure in which symbol losses caused by channel error cannot be considered. We demonstrate the performance gaps between results solved from EED versus CBD in our numerical example, and conclude that the optimization using CBD behaves awkwardly in computing proper power allocation configurations in the considered SSC-SPC architecture. View full abstract»

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  • Power-Controlled Cognitive Radio Spectrum Allocation with Chemical Reaction Optimization

    Page(s): 3180 - 3190
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    Cognitive radio is a promising technology for increasing the system capacity by using the radio spectrum more effectively. It has been widely studied recently and one important problem in this new paradigm is the allocation of radio spectrum to secondary users effectively in the presence of primary users. We call it the cognitive radio spectrum allocation problem (CRSAP) in this paper. In the conventional problem formulation, a secondary user can be either on or off and its interference range becomes maximum or zero, respectively. We first develop a solution to CRSAP based on the newly proposed chemical reaction-inspired metaheuristic called Chemical Reaction Optimization (CRO). We study different utility functions, accounting for utilization and fairness, with the consideration of the hardware constraint, and compare the performance of our proposed CRO-based algorithm with existing ones. Simulation results show that the CRO-based algorithm always outperforms the others dramatically. Next, by allowing adjustable transmission power, we propose power-controlled CRSAP (PC-CRSAP), a new formulation to the problem with the consideration of spatial diversity. We design a two-phase algorithm to solve PC-CRSAP, and again simulation results show excellent performance. View full abstract»

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  • Minimum BER Analysis in Interference Channels

    Page(s): 3191 - 3201
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    In spectrum sharing channels, a secondary user can simultaneously transmit data with a primary user as long as the so called interference temperature limit is kept less than a certain permissible level. In this paper, we consider a spectrum sharing scenario over a Nakagami-m fading channel, and formulate a minimization problem for the average bit error rate (BER) that can be achieved by a secondary user while keeping the interference level introduced to the primary user below a given threshold. We derive new results for the minimum average BER under either average or peak interference power constraints at the primary receiver. This paper also investigates the significance of having extra side information on the status of different channels at the secondary transmitter. Finally, the impact of posing additional constraints on the transmit power at the secondary transmitter is discussed via numerical results. View full abstract»

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  • Self-Organization in Small Cell Networks: A Reinforcement Learning Approach

    Page(s): 3202 - 3212
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    In this paper, a decentralized and self-organizing mechanism for small cell networks (such as micro-, femto- and picocells) is proposed. In particular, an application to the case in which small cell networks aim to mitigate the interference caused to the macrocell network, while maximizing their own spectral efficiencies, is presented. The proposed mechanism is based on new notions of reinforcement learning (RL) through which small cells jointly estimate their time-average performance and optimize their probability distributions with which they judiciously choose their transmit configurations. Here, a minimum signal to interference plus noise ratio (SINR) is guaranteed at the macrocell user equipment (UE), while the small cells maximize their individual performances. The proposed RL procedure is fully distributed as every small cell base station requires only an observation of its instantaneous performance which can be obtained from its UE. Furthermore, it is shown that the proposed mechanism always converges to an epsilon Nash equilibrium when all small cells share the same interest. In addition, this mechanism is shown to possess better convergence properties and incur less overhead than existing techniques such as best response dynamics, fictitious play or classical RL. Finally, numerical results are given to validate the theoretical findings, highlighting the inherent tradeoffs facing small cells, namely exploration/exploitation, myopic/foresighted behavior and complete/incomplete information. View full abstract»

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  • Source Power Allocation and Relaying Design for Two-Hop Interference Networks with Relay Conferencing

    Page(s): 3213 - 3225
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (467 KB) |  | HTML iconHTML  

    In this paper, we consider a two-hop interference network, which consists of two source-destination pairs and two relay nodes connected with signal-to-noise ratio (SNR) limited out-of-band conferencing links. Assuming that the amplify-and-forward (AF) relaying scheme is adopted, this network is shown to be equivalent to a two-user interference channel (IC). By deploying two IC decoding schemes, i.e., single-user decoding and joint decoding, respectively, we characterize the achievable rate regions with a two-stage iterative optimization method: First, we fix the source power pair and maximize the sum rate over the relay combining vector; second, we fix the relay combining vector and optimize the source power pair. Specifically, for single-user decoding, we design a new routine to compute the optimal solution for the first subproblem, which is more efficient than the existing scheme; and for the second subproblem, we develop an iterative algorithm, with the closed-form solution for each iteration. Furthermore, it is revealed that the AF scheme with relay conferencing achieves the full degree-of-freedom (DoF), which outperforms the case without relay conferencing. Finally, simulation results show that relay conferencing can significantly improve the system performance under certain channel conditions. View full abstract»

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  • A Feedback- Soft Sensing-Based Access Scheme for Cognitive Radio Networks

    Page(s): 3226 - 3237
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (691 KB) |  | HTML iconHTML  

    In this paper, we examine a cognitive spectrum access scheme in which secondary users exploit the primary feedback information. We consider an overlay secondary network employing a random access scheme in which secondary users access the channel by certain access probabilities that are functions of the spectrum sensing metric. In setting our problem, we assume that secondary users can eavesdrop on the primary link's feedback. We study the cognitive radio network from a queuing theory point of view. Access probabilities are determined by solving a secondary throughput maximization problem subject to a constraint on the primary queues' stability. First, we formulate our problem which is found to be non-convex. Yet, we solve it efficiently by exploiting the structure of the secondary throughput equation. Our scheme yields improved results in, both, the secondary user throughput and the primary user packet delay as compared to the scheme where no feedback information is exploited. In addition, it comes very close to the optimal genie-aided scheme in which secondary users act upon the presumed perfect knowledge of the primary users' activity. View full abstract»

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  • Network-Coded Bi-Directional Relaying for Amplify-and-Forward Cooperative Networks: A Comparative Study

    Page(s): 3238 - 3252
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    In this paper, a comparative study of network-coded bi-directional amplify-and-forward (BD-AF) relaying is presented. In bi-directional relay networks, communication is performed over two phases: the broadcasting phase, and the cooperation phase. In the broadcasting phase, both source nodes broadcast their signals simultaneously to the N relay nodes, while in the cooperation phase, transmission is based on one of two modes: (1) time-division (TD), or (2) multiple-access (MA). In the TD-BD-AF scheme, each relay node is allocated a time-slot to transmit its processed signal, while in the MA-BD-AF scheme, all the N relay nodes simultaneously transmit network-coded signals to both source nodes, in a single time-slot. Moreover, a suboptimal relay selection (i.e. SRS-BD-AF) that approximately maximizes the sum-of-rates is proposed. Optimal and suboptimal sum-of-rates maximizing power allocations are studied under the TD-BD-AF and MA-BD-AF schemes, respectively, where it is shown that the MA-BD-AF scheme reduces to the SRS-BD-AF scheme. Symbol error rate performance analysis is provided, where it is shown that both the TD-BD-AF and SRS-BD-AF schemes achieve full diversity. Imperfect timing synchronization is analyzed and it is demonstrated that the SRS-BD-AF outperforms the other schemes in terms of the achievable rate. Simulation results are provided to complement the theoretical analysis. View full abstract»

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  • Minimum-Energy Power and Rate Control for Fair Scheduling in the Cellular Downlink under Flow Level Delay Constraint

    Page(s): 3253 - 3263
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    In this paper, we study the energy-delay trade-off in the downlink of a proportional-fair cellular system with inter-cell interference and fading, while incorporating the efficiency characteristics of realistic amplifiers(PA). We study the potential for energy saving by lowering the transmission power level at different user locations in a cell at the cost of additional flow level delay. We identify the transmission power levels at different locations so that the energy consumption at the base station is minimized and the flow level delay is controlled. We formulate the energy minimization problem in a game theoretic framework and prove the convergence of the best response iteration algorithm. The energy saving potential is found to depend on the network load and the efficiency characteristics of the PAs. There is a significant potential for energy saving when the network operates under low to medium loads and efficient PAs are utilized. For example, with envelope tracking PA, around 90% of energy can be saved by introducing small additional flow level delay when the network load is less than 75%. Motivated by the fact that the network load keeps varying throughout the day, we take a daily traffic model and demonstrate the potential for energy saving by this scheme. View full abstract»

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  • Interference Management in Underlay Spectrum Sharing Using Indirect Power Control Signalling

    Page(s): 3264 - 3277
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    In this paper, we propose an interference management method for underlay spectrum sharing and evaluate its performance. In this method the secondary service has been facilitated by granting passive access to the power control signalling transmitted by the primary network base station. To exploit both slow shadowing and fast fading, the proposed method performs secondary service power management in two phases, each in different time-scales: rate optimal power allocation phase and interference reduction power adjustment phase. In the longer time-scale, rate optimal power allocation phase adaptively allocates the secondary transmit power exploiting the medium-scale channel variations (shadowing effect) of the secondary channel to maximize its capacity. In the shorter time-scale, interference reduction power adjustment phase exploits the power control commands transmitted in the primary network to adaptively adjust secondary service transmission power for reducing the effects of the secondary service transmission on the Quality-of-Service (QoS) of the primary service network. The main advantage of this method which is referred to as Adaptive Multiple Time-Scale Power Allocation (AMTPA) is that it does not require direct signaling between the two systems. We further present AMTPA analytical performance evaluation results. Practical considerations are also presented regarding the primary network requirements and its power control feasibility after adopting AMTPA in the secondary network. Extensive simulation results indicate significant improvement in the system performance by using AMTPA. Using simulations we also show how one can set AMTPA parameters so that a certain level of QoS in the primary network is satisfied. View full abstract»

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  • Optimal Distributed Scheduling under Time-Varying Conditions: A Fast-CSMA Algorithm with Applications

    Page(s): 3278 - 3288
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (517 KB) |  | HTML iconHTML  

    Recently, low-complexity and distributed Carrier Sense Multiple Access (CSMA)-based scheduling algorithms have attracted extensive interest due to their throughput-optimal characteristics in general network topologies. However, these algorithms are not well-suited for time-varying environments (i.e., serving real-time traffic under time-varying channel conditions in wireless networks) for two reasons: (1) the mixing time of the underlying CSMA Markov Chain grows with the size of the network, which, for large networks, generates unacceptable delay for deadline-constrained traffic; (2) since the dynamic CSMA parameters are influenced by the arrival and channel state processes, the underlying CSMA Markov Chain may not converge to a steady-state under strict deadline constraints and fading channel conditions. In this paper, we attack the problem of distributed scheduling for time-varying environments. Specifically, we propose a Fast-CSMA (FCSMA) policy in fully-connected topologies, which converges much faster than the existing CSMA algorithms and thus yields significant advantages for time-varying applications. Then, we design optimal policies based on FCSMA techniques in two challenging and important scenarios in wireless networks for scheduling inelastic traffic with/without channel state information (CSI) over wireless fading channels. View full abstract»

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  • Diversity-Multiplexing Trade-off for Coordinated Direct and Relay Schemes

    Page(s): 3289 - 3299
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    The recent years have brought a significant body of research on wireless Two-Way Relaying (TWR), where the use of network coding brings an evident advantage in terms of data rates. Yet, TWR scenarios represent only a special case and it is of interest to devise similar techniques in more general multi-flow scenarios. Such techniques can leverage on the two principles used in Wireless Network Coding to design throughput-efficient schemes: (1) aggregation of communication flows and (2) embracing and subsequently cancel/mitigate the interference. Using these principles, we investigate Coordinated Direct/Relay (CDR) schemes, which involve two flows, of a direct and a relayed user. In this paper we characterize a CDR scheme by deriving/bounding the Diversity-Multiplexing Trade-off (DMT) function. Two cases are considered. In the first case a transmitter knows the Channel State Information (CSI) of all the links in the network, while in the second case each node knows only CSI of the links towards its neighbors. The results show that the new CDR scheme outperforms the reference scheme in terms of DMT characterization. Several interesting features are identified with respect to the impact of the CSI knowledge to the improvement in diversity or multiplexing brought by the CDR scheme. View full abstract»

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  • Multicell Coordination via Joint Scheduling, Beamforming, and Power Spectrum Adaptation

    Page(s): 1 - 14
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (451 KB) |  | HTML iconHTML  

    The mitigation of intercell interference is an importance issue for current and next-generation wireless cellular networks where frequencies are aggressively reused and hierarchical cellular structures may heavily overlap. The paper examines the benefit of coordinating transmission strategies and resource allocation schemes across multiple base-stations for interference mitigation. Two different wireless cellular architectures are studied: a multicell network where base-stations coordinate in their transmission strategies, and a mixed macrocell and femtocell/picocell deployment with coordination among macro and femto/pico base-stations. For both scenarios, this paper proposes a heuristic joint proportionally fair scheduling, spatial multiplexing, and power spectrum adaptation algorithm that coordinates multiple base-stations with an objective of optimizing the overall network utility. The proposed scheme optimizes the user schedule, transmit and receive beamforming vectors, and transmit power spectra jointly, while taking into consideration both the intercell and intracell interference and the fairness among the users. System-level simulation results show that coordination at the transmission strategy and resource allocation level can already significantly improve the overall network throughput as compared to a conventional network design with fixed transmit power and per-cell zero-forcing beamforming. View full abstract»

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  • Exploiting Multi-User Diversity and Multi-Hop Diversity in Dual-Hop Broadcast Channels

    Page(s): 3314 - 3325
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    We propose joint user-and-hop scheduling over dual-hop block-fading broadcast channels in order to exploit multi-user diversity gains and multi-hop diversity gains all together. To achieve this objective, the first and second hops are scheduled opportunistically based on the channel state information. The joint scheduling problem is formulated as maximizing the weighted sum of the long term achievable rates of the users under a stability constraint, which means that in the long term the rate received by the relay should equal the rate transmitted by it, in addition to power constraints. We show that this problem is equivalent to a single-hop broadcast channel by treating the source as a virtual user with an optimal weight that maintains the stability constraint. We show how to obtain the source weight either off-line based on channel statistics or on real-time based on channel measurements. Furthermore, we consider special cases including the maximum sum-rate scheduler and the proportional fair scheduler. We also show how to extend the scheme into one that allows multiple user scheduling via superposition coding with successive decoding. Numerical results demonstrate that our proposed joint scheduling scheme enlarges the rate region as compared to scheduling schemes that exploit the diversity gains partially. View full abstract»

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  • Quasi-Nash Equilibria for Non-Convex Distributed Power Allocation Games in Cognitive Radios

    Page(s): 3326 - 3337
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (806 KB) |  | HTML iconHTML  

    In this paper, we consider a sensing-based spectrum sharing scenario in cognitive radio networks where the overall objective is to maximize the sum-rate of each cognitive radio user by optimizing jointly both the detection operation based on sensing and the power allocation, taking into account the influence of the sensing accuracy and the interference limitation to the primary users. The resulting optimization problem for each cognitive user is non-convex, thus leading to a non-convex game, which presents a new challenge when analyzing the equilibria of this game where each cognitive user represents a player. In order to deal with the non-convexity of the game, we use a new relaxed equilibria concept, namely, quasi-Nash equilibrium (QNE). A QNE is a solution of a variational inequality obtained under the first-order optimality conditions of the player's problems, while retaining the convex constraints in the variational inequality problem. In this work, we state the sufficient conditions for the existence of the QNE for the proposed game. Specifically, under the so-called linear independent constraint qualification, we prove that the achieved QNE coincides with the NE. Moreover, a distributed primal-dual interior point optimization algorithm that converges to a QNE of the proposed game is provided in the paper, which is shown from the simulations to yield a considerable performance improvement with respect to an alternating direction optimization algorithm and a deterministic game. View full abstract»

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  • Energy-Efficient Communication via Feedback

    Page(s): 3338 - 3349
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (430 KB) |  | HTML iconHTML  

    We propose a feedback optimization framework to minimize the total energy consumption in point-to-point wireless communication links. The energy cost of both the forward link and the feedback link are taken into account. Given the energy consumption profile of both links, we minimize error probability subject to the total energy budget and a delay constraint. The proposed framework is based on a multi-phase feedback scheme in which a transmission, if decoded incorrectly, is followed by a retransmission with boosted energy. We use this framework to show that the gain of utilizing feedback is highly dependent on the energy consumption profile of the links and the total available energy. In particular, we identify scenarios in which the use of feedback significantly increases the energy efficiency, as well as scenarios where, surprisingly, the use of feedback is strictly suboptimal as compared to communication without feedback. View full abstract»

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  • Performance of TAS/MRC Wireless Systems Under Hoyt Fading Channels

    Page(s): 3350 - 3359
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (395 KB) |  | HTML iconHTML  

    This paper presents the performance analysis of a wireless system with multiple transmit and receive antennas under Hoyt fading. Receive antennas are assumed to perform Maximal Ratio Combining (MRC), whereas the antenna at the transmit end that maximizes the instantaneous output signal-to-noise ratio (SNR) is selected for transmission. When the number of receive antennas is arbitrary, an exact compact expression is derived for the outage probability. For two receive antennas, closed-form expressions are presented for the ergodic capacity and the average error rates of different modulations, which are given as a finite sum of well known functions. An asymptotic error rate analysis is also performed when the number of receive antennas is arbitrary. It is shown that severe fading conditions do not always degrade wireless systems performance. Actually, our results show that severe fading can be beneficial in terms of channel capacity if the transmit array is large enough due to the antenna selection performed at the transmitter. Monte Carlo simulations have been carried out to validate the derived expressions, showing an excellent agreement with the analytical results. View full abstract»

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  • Wireless Mesh Network in Smart Grid: Modeling and Analysis for Time Critical Communications

    Page(s): 3360 - 3371
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    Communication networks are an indispensable component in the smart grid power systems by providing the essential information exchange functions among the electrical devices that are located distributively in the grid. In particular, wireless networks will be deployed widely in the smart grid for data collection and remote control purposes. In this paper, we model the smart grid wireless networks and present the communication delay analysis in typical wireless network deployment scenarios in the grid. As the time critical communications are coupled with the power system protections in the smart grid, it is important to understand the delay performance of the smart grid wireless networks. Our results provide the delay bounds that can help design satisfactory wireless networks to meet the demanding communication requirements in the smart grid. View full abstract»

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  • Secure Wireless Multicast for Delay-Sensitive Data via Network Coding

    Page(s): 3372 - 3387
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (910 KB) |  | HTML iconHTML  

    Wireless multicast for delay-sensitive data is challenging because of the heterogeneity effect where each receiver may experience different packet losses. Fortunately, network coding, a new advanced routing protocol, offers significant advantages over the traditional Automatic Repeat reQuest (ARQ) protocols in that it mitigates the need for retransmission and has the potential to approach the min-cut capacity. Network-coded multicast would be, however, vulnerable to false packet injection attacks, in which the adversary injects bogus packets to prevent receivers from correctly decoding the original data. Without a right defense in place, even a single bogus packet can completely change the decoding outcome. Existing solutions either incur high computation cost or cannot withstand high packet loss. In this paper, we propose a novel scheme to defend against false packet injection attacks on network-coded multicast for delay-sensitive data. Specifically, we propose an efficient authentication mechanism based on null space properties of coded packets, aiming to enable receivers to detect any bogus packets with high probability. We further design an adaptive scheduling algorithm based on the Markov Decision Processes (MDP) to maximize the number of authenticated packets received within a given time constraint. Both analytical and simulation results have been provided to demonstrate the efficacy and efficiency of our proposed scheme. View full abstract»

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The IEEE Transactions on Wireless Communications publishes high-quality manuscripts on advances in the state-of-the-art of wireless communications.

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Jeff Andrews
Cullen Trust for Higher Education Endowed Professor of Engineering