# IEEE Communications Letters

## Filter Results

Displaying Results 1 - 25 of 56

Publication Year: 2017, Page(s):C1 - 1678
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• ### IEEE Communications Society

Publication Year: 2017, Page(s): C2
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• ### A Novel Scrambler Design for Enhancing Secrecy Transmission Based On Polar Code

Publication Year: 2017, Page(s):1679 - 1682
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Scrambling is a way of enhancing physical layer security presented in many papers. However, few of these papers have mentioned the scrambling effect on the polar coding secrecy. In this letter, we introduce a new scrambling module combined with a polar coding system, in which pre-assigned key is unnecessary. The presented scrambling module combines linear and nonlinear structure. The presented lin... View full abstract»

• ### Binary Locally Repairable Codes With Minimum Distance at Least Six Based on Partial $t$ -Spreads

Publication Year: 2017, Page(s):1683 - 1686
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We propose a new construction for binary locally repairable codes (LRCs) based on a (partial) t-spread, which constructs an LRC with minimum distance d ≥ 6 and any locality r ≥ 2. Furthermore, we found that there are some cases in which the resulting codes are optimum in terms of the upper bound by Cadambe and Mazumdar in 2015. View full abstract»

• ### Alphabet-Dependent Bounds for Locally Repairable Codes With Joint Information Availability

Publication Year: 2017, Page(s):1687 - 1690
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In this letter, we investigate a class of codes with the following property: any decodable set of erased symbols can be repaired from any single set of several disjoint symbol sets with small cardinality. We refer such codes to locally repairable codes (LRCs) with joint availability. In particular, if information symbols of a code have this property, then we refer the code to an LRC with joint inf... View full abstract»

• ### A New Construction of Exact-Repair MSR Codes Using Linearly Dependent Vectors

Publication Year: 2017, Page(s):1691 - 1694
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Regenerating codes focus on the efficient repair of node failures. In an [n, k, d] regenerating code system, any k nodes can retrieve the original data and any d nodes can repair a failed node by giving out β pieces of data per node. For minimum storage regenerating (MSR) codes, d ≥ 2k - 3 has been proved. However, as far as we know, there is no construction of exact-repair MSR codes... View full abstract»

• ### Asymmetric Spatially Coupled LDPC Codes for Multiple-Burst Erasure Channels

Publication Year: 2017, Page(s):1695 - 1698
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The outstanding performances of spatially coupled low-density parity-check (SC-LDPC) codes deteriorate over the channels with memory due to burst erasures. In order to improve the performances of SC-LDPC codes over multiple-burst erasure channels, an asymmetric spatial coupling (ASC) structure is proposed, where each variable node at the same position of the coupled protograph can flexibly choose ... View full abstract»

• ### An Expurgating-Based Method for Constructing Multi-Rate Non-Binary Quasi-Cyclic LDPC Codes

Publication Year: 2017, Page(s):1699 - 1702
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This letter presents a new method for constructing the multi-rate non-binary quasi-cyclic low-density parity-check codes by expurgating a high-rate mother code. A matrix-theoretic approach is applied to design the parity-check matrices of the proposed codes. The resulting codes possess a quasi-cyclic structure, which is desirable for hardware implementations of the encoder and decoder. The codes c... View full abstract»

• ### GPU-Based Gigabit LDPC Decoder

Publication Year: 2017, Page(s):1703 - 1706
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In this letter, we present design and implementation of a parallel software low-density parity-check (LDPC) decoding algorithm on graphics processing units (GPUs). As a solution for the LDPC decoder, dedicated application-specific integrated circuit or field programmable gate array implementations is proposed in recent years in order to support high throughput despite their long deployment cycle, ... View full abstract»

• ### Dimension Boundary Between Finite and Infinite Random Matrices in Cognitive Radio Networks

Publication Year: 2017, Page(s):1707 - 1710
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The dimension boundary between finite random matrices and infinite random matrices is originally defined in this letter. The proposed boundary provides a theoretical approach to classify random matrices based on their dimensions. Two methods are proposed to determine the dimension boundary. One is based on the eigenvalue distribution and the other is based on the eigenvalue interval. In particular... View full abstract»

• ### On the Design of Matched Filters for Molecule Counting Receivers

Publication Year: 2017, Page(s):1711 - 1714
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In this letter, we design matched filters for diffusive molecular communication systems taking into account the following impairments: signal-dependent diffusion noise, inter-symbol interference (ISI), and external interfering molecules. The receiver counts the number of observed molecules several times within one symbol interval and employs linear filtering to detect the transmitted data. We deri... View full abstract»

• ### Distributed Decoding for Coded Slotted ALOHA

Publication Year: 2017, Page(s):1715 - 1718
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In this letter, we propose a distributed decoding algorithm for the coded slotted ALOHA multiple access scheme. To recover the transmitted packets, the proposed algorithm applies a swap and a back substitution operation on each received packet. As a result, the hidden information in the collided packets can be drawn out immediately to help the decoding, and a high throughput can be achieved. The d... View full abstract»

• ### White Gaussian Chaos

Publication Year: 2017, Page(s):1719 - 1722
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A discrete-time white Gaussian noise (WGN) is a random process with impulsive autocorrelation function. Also, the random variables obtained by sampling the process at any time instants are jointly Gaussian. WGN is widely used to model noise in engineering and physics. In this letter, we propose a way to generate chaotic signals that behave like WGN, due to the features of its autocorrelation funct... View full abstract»

• ### Scaling Factor Aided Iterative Multiuser Receiver for Sparse Code Multiple Access

Publication Year: 2017, Page(s):1723 - 1726
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Sparse code multiple access (SCMA) is a promising nonorthogonal multiple access scheme for the 5G system. In this letter, we introduce a scaling factor (SF) to scale the extrinsic information exchanged between the detector and the decoders to further improve the performance of iterative multiuser receiver (IMR) in SCMA. Appropriate SF is selected by using the extrinsic information transform chart ... View full abstract»

• ### Protocol Verification by Simultaneous Reachability Graph

Publication Year: 2017, Page(s):1727 - 1730
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Non-executable transitions, deadlock states, and livelock cycles are typical errors in communication protocols. Reachability analysis is a direct method to detect these errors, while the state-space explosion is the most severe limitation to such a method. In this letter, a relief strategy is proposed by using the simultaneous reachability graph-a simple graph generated by the simultaneous executi... View full abstract»

• ### Error Concealment for 3-D DWT Based Video Codec Using Iterative Thresholding

Publication Year: 2017, Page(s):1731 - 1734
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Error concealment for video coding based on a 3-D discrete wavelet transform (DWT) is considered. We assume that the video sequence has a sparse representation in a known basis different from the DWT, e.g., in a 2-D discrete cosine transform basis. Then, we formulate the concealment problem as l1-norm minimization and solve it utilizing an iterative thresholding algorithm. Comparing dif... View full abstract»

• ### A Parallel Belief Propagation Decoding Algorithm for Rate Compatible Modulation

Publication Year: 2017, Page(s):1735 - 1738
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This letter proposes a parallel belief propagation algorithm for fast iterative decoding of rate compatible modulation. In this proposed algorithm, the processing at symbol node is partitioned into several low complexity sub-processors. All sub-processors have similar structures and work in parallel without cross connections among them. Numerical and simulation results show that proper partition r... View full abstract»

• ### A Majorization–Minimization Approach for Reducing Out-of-Band Radiations in OFDM Systems

Publication Year: 2017, Page(s):1739 - 1742
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This letter is concerned with the reduction of the out-of-band (OOB) components in spectrum of orthogonal frequency division multiplexing (OFDM) systems. We propose an efficient method to obtain a phase sequence that is required in a phase adjustment algorithm, an algorithm which reduces the OOB components by employing proper phase shifts in OFDM symbols. The proposed method is based on the majori... View full abstract»

• ### GFDM BER Under Synchronization Errors

Publication Year: 2017, Page(s):1743 - 1746
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Generalized frequency division multiplexing (GFDM) is a candidate waveform for the air interface of the fifth generation mobile network. In one of the foreseen scenarios for this future network, known as massive machine type communication, the demand for a low power consumption and a loose synchronization scheme might result in residual symbol-time and carrier-frequency offsets. The overall system... View full abstract»

• ### Generalization of the Phase Shift Condition in “Intrinsic ICI-Free Alamouti Coded FBMC”

Publication Year: 2017, Page(s):1747 - 1750
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The condition given in (5) of the paper “Intrinsic ICI-Free Alamouti Coded FBMC” accomplishes the desired property, i.e., ICI-free performance of frequency reversal alamouti coded FBMC. However, this condition is sufficient but not necessary as it corresponds to a subset of the solutions. We show that this condition can be relaxed to cover more general solutions. This generalization ... View full abstract»

• ### Construction and Labeling of Triangular QAM

Publication Year: 2017, Page(s):1751 - 1754
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We propose two algorithms: one is for building and the other for labeling triangular QAM (TQAM) constellations. A root distribution algorithm (also referred as RD) is used to construct TQAM constellations of low average energy. The proposed labeling algorithm, termed the layer labeling algorithm, results in bit-to-symbol mappings that minimize the average Hamming distance between constellation poi... View full abstract»

• ### Success Probability of Multiple-Preamble-Based Single-Attempt Random Access to Mobile Networks

Publication Year: 2017, Page(s):1755 - 1758
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We analyze the tradeoff between collision probability and code-ambiguity, when devices transmit a sequence of preambles as a codeword, instead of a single preamble, to reduce collision probability during random access to a mobile network. We point out that the network may not have sufficient resources to allocate to every possible codeword, and, if it does, this results in low utilization of alloc... View full abstract»

• ### Broadband Optical Sources for Low-Cost WDM-MB-OFDM Networks

Publication Year: 2017, Page(s):1759 - 1762
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Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) signal transmission through a 10-km optical fiber link is experimentally demonstrated by using a broadband source. We propose the use of optical broadband sources in multiband OFDM signal transmitters as a low-cost and power fading free solution. The OFDM band is dynamically selected in the receiver by means of an Mach-Zehnder Interfer... View full abstract»

• ### On Multiple Controller Mapping in Software Defined Networks With Resilience Constraints

Publication Year: 2017, Page(s):1763 - 1766
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We propose an effective switch-controller mapping scheme for distributed controller architectures in software defined networks. Our scheme maps a switch to multiple controllers and distributes flow setup requests among them to minimize flow setup time, satisfying the resilience constraint, which requires that a specified fraction of setup requests at each switch is not affected upon a controller f... View full abstract»

• ### On the Trade-Off Between Computational Load and Reliability for Network Function Virtualization

Publication Year: 2017, Page(s):1767 - 1770
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Network function virtualization enables the “softwarization” of network functions, which are implemented on virtual machines hosted on commercial off-the-shelf servers. Both the composition of the virtual network functions into a forwarding graph (FG) at the logical layer and the embedding of the FG on the servers need to consider the less-than-carrier-grade reliability of COTS compo... View full abstract»

## Aims & Scope

IEEE Communications Letters publishes letters on the frontiers of research within the field of interest of the IEEE Communications Society in a timely manner.

Full Aims & Scope

Editor-in-Chief
Octavia Dobre