# IEEE Communications Letters

## Filter Results

Displaying Results 1 - 25 of 56

Publication Year: 2016, Page(s):C1 - 1272
| PDF (339 KB)
• ### IEEE Communications Society

Publication Year: 2016, Page(s): C2
| PDF (92 KB)
• ### A Combined Algebraic- and Graph-Based Method for Constructing Structured RC-LDPC Codes

Publication Year: 2016, Page(s):1273 - 1276
| | PDF (732 KB) | HTML

This letter presents a new method for constructing rate-compatible low-density parity-check (RC-LDPC) codes, which is based on combining algebraic-based and graph-based construction methods. We first use a graph-based tool, protograph extrinsic information transfer chart, to construct a masking matrix. Then, the parity-check matrices of RC-LDPC codes are determined in accordance with the framework... View full abstract»

• ### A Low Complexity Encoding Algorithm for Systematic Polar Codes

Publication Year: 2016, Page(s):1277 - 1280
Cited by:  Papers (1)
| | PDF (476 KB) | HTML

Arıkan has shown that systematic polar codes (SPC) outperform non-SPC (NSPC). However, the performance gain comes at the price of elevated encoding complexity, i.e., compared with NSPC, the available encoding methods for SPC require higher memory and computation. In this letter, we propose an efficient encoding algorithm requiring only N bits of memory and having (N/2)log2N XOR o... View full abstract»

• ### General Sub-Packetized Access-Optimal Regenerating Codes

Publication Year: 2016, Page(s):1281 - 1284
Cited by:  Papers (1)
| | PDF (374 KB) | HTML

This letter presents a novel construction of (n, k, d = n - 1) access-optimal regenerating codes for an arbitrary sub-packetization level α for exact repair of any systematic node. We refer to these codes as general sub-packetized, because we provide an algorithm for constructing codes for any α less than or equal to r[(k/r)], where (k/r) is not necessarily an integer. Thi... View full abstract»

• ### Superposition Construction of $Q$ -Ary LDPC Codes by Jointly Optimizing Girth and Number of Shortest Cycles

Publication Year: 2016, Page(s):1285 - 1288
Cited by:  Papers (1)
| | PDF (430 KB) | HTML

In this letter, we consider the construction of q-ary low-density parity-check (LDPC) codes by jointly optimizing the girth and number of shortest cycles in the frame of superposition. We begin with constructing binary quasi-cyclic LDPC codes by superposition. By replacing the nonzero entries of the parity-check matrices of the resulting binary codes with the nonzero elements of GF(q), a class of ... View full abstract»

• ### A New Construction of $(k+2,k)$ Minimal Storage Regenerating Code Over F3 With Optimal Access Property for All Nodes

Publication Year: 2016, Page(s):1289 - 1292
| | PDF (341 KB) | HTML

The optimal access property is highly desirable for distributed storage systems. In this letter, based on the (k+2,k) zigzag code, we propose a new (k+2,k) minimal storage regenerating code. The new code inherits the key properties of the zigzag code, such as the optimal access property for all systematic nodes and small alphabet F3. Furthermore, the new code possesses the optimal acces... View full abstract»

• ### Two New Classes of Two-Parity MDS Array Codes With Optimal Repair

Publication Year: 2016, Page(s):1293 - 1296
Cited by:  Papers (2)
| | PDF (420 KB) | HTML

Two-parity maximum distance separable (MDS) array codes achieve the lowest storage overhead for tolerating two erasures. In this letter, we propose two new classes of twoparity MDS array codes over finite field F2, with which each single node failure can be recovered by reading the minimum amount of data from each surviving node. View full abstract»

• ### Lattice-Reduction-Aided Partial Marginalization for Soft Output MIMO Detector With Fixed and Reduced Complexity

Publication Year: 2016, Page(s):1297 - 1300
Cited by:  Papers (1)
| | PDF (438 KB) | HTML

In this letter, we propose lattice-reduction (LR)-aided partial marginalization (PM) for soft output multiple-input multiple-output (MIMO) detection. PM has the advantages of a fully predictable runtime and convenience in parallelization while offering a well-defined tradeoff between the performance and the computational complexity. However, the computational complexity of PM to achieve a high lev... View full abstract»

• ### A Serial IFFT Precoding Scheme to Mitigate the Periodic Noise in OFDM System

Publication Year: 2016, Page(s):1301 - 1304
| | PDF (910 KB) | HTML

In this letter, we propose a serial Inverse Fast Fourier Transform precoding method to mitigate the periodic noise in orthogonal frequency division multiplexing (OFDM) systems. The principle of the method is given and the feasibility is proved theoretically. In addition, in a single light emitting diode-based visible light communication OFDM experimental system with periodic noise, a comparison be... View full abstract»

• ### How Much Does I/Q Imbalance Affect Secrecy Capacity?

Publication Year: 2016, Page(s):1305 - 1308
Cited by:  Papers (5)
| | PDF (1804 KB) | HTML

Radio frequency front ends constitute a fundamental part of both conventional and emerging wireless systems. However, in spite of their importance, they are often assumed ideal, although they are practically subject to certain detrimental impairments, such as amplifier nonlinearities, phase noise, and in-phase and quadrature (I/Q) imbalance (IQI). This letter is devoted to the quantification and e... View full abstract»

• ### Optimal Buffer-Aided Relaying With Imperfect CSI

Publication Year: 2016, Page(s):1309 - 1312
Cited by:  Papers (3)
| | PDF (495 KB) | HTML

In this letter, we consider a two-hop relay channel that consists of a source, a half-duplex decode-and-forward relay, and a destination. We derive the optimal buffer-aided relaying policy based on imperfect channel state information (CSI) and under long-term per-node power constraints for the source and the relay. In particular, the proposed protocol determines the optimal state of the relay node... View full abstract»

• ### On the Compactness of OFDM and Hermite Signals

Publication Year: 2016, Page(s):1313 - 1316
Cited by:  Papers (1)
| | PDF (474 KB) | HTML

In this letter, the compactness of the orthogonal frequency division multiplexing (OFDM) and orthogonal Hermite signals is compared by measuring their time-bandwidth products (TBPs). In a theory, it has been shown that the Hermite functions provided the minimum possible TBP among all orthogonal functions; however, this minimum is obtained from the root mean square sense, which is not useful for mo... View full abstract»

• ### Asymptotically Optimal Power Allocation for WSNs With Mutually Correlated Sensing Data

Publication Year: 2016, Page(s):1317 - 1320
Cited by:  Papers (1)
| | PDF (446 KB) | HTML

It is well known that distributed source coding can improve the reliability and energy efficiency of wireless sensor networks by exploiting the correlation among sensing data. In this letter, we strengthen the benefits of such an approach by proposing a simple, general, efficient power allocation scheme for an arbitrary amount of sensors. The proposed power allocation is asymptotically optimal at ... View full abstract»

• ### Differential Entropy-Driven Spectrum Sensing Under Generalized Gaussian Noise

Publication Year: 2016, Page(s):1321 - 1324
Cited by:  Papers (2)
| | PDF (686 KB) | HTML

We propose a novel goodness-of-fit detection scheme for spectrum sensing, based on differential entropy in the received observations. The noise distribution is known to deviate from the Gaussian in many practical communication settings. We, therefore, permit that the noise process follows the generalized Gaussian distribution, which subsumes Gaussian and Laplacian as special cases. We obtain, in c... View full abstract»

• ### A Signaling Protocol for Service Function Localization

Publication Year: 2016, Page(s):1325 - 1328
Cited by:  Papers (2)
| | PDF (1602 KB) | HTML

Current proposals for chaining service functions (SFs) do not address some critical management issues, such as the discovery of SF instances close to IP data paths. This information is crucial for deploying complex services both in large cloud networks, where SFs may be moved or replicated, and in the emerging fog/mobile edge computing systems. For this purpose, in this letter, we propose the dist... View full abstract»

• ### Robust Transmit Beamforming for Parameter Estimation Using Distributed Sensors

Publication Year: 2016, Page(s):1329 - 1332
Cited by:  Papers (2)
| | PDF (303 KB) | HTML

In this letter, we study the problem of estimating a complex parameter in a wireless sensor network under individual power constraints and bounded channel uncertainty, where the channel state information is assumed to be imperfect at both the sensors and the fusion center. Transmit beamformers and a linear estimator that minimize the maximum mean square error are found. Although this problem is no... View full abstract»

• ### Source Separation Approach to Video Quality Prediction in Computer Networks

Publication Year: 2016, Page(s):1333 - 1336
Cited by:  Papers (1)
| | PDF (440 KB) | HTML

Time-varying loads introduce errors in the estimated model parameters of service-level predictors in computer networks. A load-adjusted modification of a traditional unadjusted service-level predictor is contributed, based on source separation. It mitigates these errors and improves the service-quality predictions for video-on-demand by ≈ 0.6 -2 dB. View full abstract»

• ### Keyword Mining for Private Protocols Tunneled Over WebSocket

Publication Year: 2016, Page(s):1337 - 1340
Cited by:  Papers (2)
| | PDF (497 KB) | HTML

WebSocket is a promising technique to build a real-time low-cost bidirectional communication channel. It supports arbitrary application-layer protocols including privately designed ones. The use of WebSocket poses a new challenge to network traffic management and security inspection. To increase visibility for WebSocket traffic, this letter proposes an automatic keyword mining approach for protoco... View full abstract»

• ### Oversubscription Dimensioning of Next-Generation PONs With Different Service Levels

Publication Year: 2016, Page(s):1341 - 1344
| | PDF (667 KB) | HTML

This letter provides a methodology for planning passive optical networks (PONs) using the oversubscription concept and shows its applicability in the dimensioning of 1 Gb/s access to both the basic (i.e., residential) and premium (i.e., business) users with different service level requirements and activity patterns. We show that only next-generation PON networks can reach a large number of users w... View full abstract»

• ### Generalized Analysis of Convergence of Absolute Trust in Peer-to-Peer Networks

Publication Year: 2016, Page(s):1345 - 1348
| | PDF (649 KB) | HTML

Open and anonymous nature of peer-to-peer networks provides an opportunity for malicious peers to behave unpredictably in the network. This leads to lack of trust among peers. To control the behavior of peers in the network, a reputation system can be used. In the reputation system, aggregation of trust is a primary issue. Algorithm for aggregation of trust should be designed, such that it can con... View full abstract»

• ### Signal Characterization and Receiver Design for Visible Light Communication Under Weak Illuminance

Publication Year: 2016, Page(s):1349 - 1352
Cited by:  Papers (2)
| | PDF (690 KB) | HTML

We characterize the received signals and propose corresponding detection methods for the visible light communication under weak illuminance. Photo-multiplier tube is employed as the receiver, which can amplify weak photon-level signal down to a series of electrons. It is observed that under the extremely low transmission power, the received signals can be characterized by the discontinuous pulses.... View full abstract»

• ### Optimal VDC Service Provisioning in Optically Interconnected Disaggregated Data Centers

Publication Year: 2016, Page(s):1353 - 1356
| | PDF (616 KB) | HTML

Virtual data center (VDC) is a key service in modern data center (DC) infrastructures. However, the rigid architecture of traditional servers inside DCs may lead to blocking situations when deploying VDC instances. To overcome this problem, the disaggregated DC paradigm is introduced. In this letter, we present an integer linear programming (ILP) formulation to optimally allocate VDC requests on t... View full abstract»

• ### On the Perfect Privacy: A Statistical Analysis of Network Traffic Approach

Publication Year: 2016, Page(s):1357 - 1360
| | PDF (497 KB) | HTML

Many recent studies reveal that merely encrypting the source content does not inhibit the adversary from gaining knowledge about the source's behavior. Thus, the adversary might be able to extract information from the network traffic by employing statistical analysis. Based on the information theory, in this letter, we quantify the amount of knowledge obtained by an adversary that overhears the ch... View full abstract»

• ### Secret-Key Agreement for Security in Multi-Emitter Visible Light Communication Systems

Publication Year: 2016, Page(s):1361 - 1364
Cited by:  Papers (2)
| | PDF (383 KB) | HTML

This letter examines secret key agreement for physical layer security in multiple-input single-output (MISO) visible light communications (VLC) systems. Upper and lower bounds are presented for the single-input single-output VLC secret-key capacities, followed by the analysis of an MISO VLC secret-key transmission strategy. A two-stage numerical approach based on fractional programming is presente... 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