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Research Interests: Mathematics, Computer Science, Information Theory, Discrete Mathematics, Iterative Decoding, and 10 moreTime Complexity, Communication Channels, Linear Code, Information Rate, Linear Time, Electrical And Electronic Engineering, Channel Capacity, Code Block, Serial Concatenated Convolutional Codes, and Exponential Decay
This paper is devoted to the problem of error detection with quantum codes. We show that it is possible to give a consistent definition of the undetected error event. To prove this, we examine possible problem settings for quantum error... more
This paper is devoted to the problem of error detection with quantum codes. We show that it is possible to give a consistent definition of the undetected error event. To prove this, we examine possible problem settings for quantum error detection. Our goal is to derive a functional that describes the probability of undetected error under natural physical assumptions concerning transmission with error detection with quantum codes. We discuss possible transmission protocols with stabilizer and unrestricted quantum codes. The set of ...
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Research Interests: Modulation, Fading Channel, Antenna arrays, MIMO, Antenna Theory, and 13 moreInformation Transfer, Iterative Decoding, Fading, Mutual Information, Detectors, MIMO channel modeling, Signal Detection, TRANSMITTERS, Curve fitting, Electrical And Electronic Engineering, Fading channels, Multiple Input Multiple Output, and Additive White Gaussian Noise
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ABSTRACT A large scale antenna system (LSAS) entails a large number of base station (BS) antennas serving a much smaller number of terminals. LSAS demonstrates large gain in spectral-efficiency and energy-efficiency compared with... more
ABSTRACT A large scale antenna system (LSAS) entails a large number of base station (BS) antennas serving a much smaller number of terminals. LSAS demonstrates large gain in spectral-efficiency and energy-efficiency compared with conventional MIMO schemes. In the regime of infinite number of BS antennas, the performance of LSAS can be improved unboundedly by using a multi-cell cooperation method called pilot contamination precoding (PCP). As the number of BS antennas grows PCP completely cancels inter-cell interference resulted from unavoidable use of nonorthogonal pilot sequences in neighboring cells. In this paper, we consider downlink PCP design in the finite antenna regime, where besides pilot contamination, three other types of interference become prominent. We formulate the PCP design as maximizing the minimum signal to interference-plus-noise ratio (SINR) subject to network sum power constraint. We propose optimal and simple suboptimal algorithms for finding PCP matrices. We show that in a practical scenario, say with M = 100 antennas, these approaches give very significant improvement over conventional LSASs.
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A new asymptotic upper bound on the size of binary codes with the property described inthe title is derived. The proof relies on the properties of the distance distribution of binarycodes established in earlier related works of the... more
A new asymptotic upper bound on the size of binary codes with the property described inthe title is derived. The proof relies on the properties of the distance distribution of binarycodes established in earlier related works of the authors. 1 IntroductionLet C 2 Zn2 be a binary block code. One says that C corrects r errors if every sphere ofradius r in Zn2 contains at most one codevector and r is the maximal number with suchproperty. Relaxing this definition, one may require that every such sphere contain at mostm vectors from the code. ...
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... complexity, and allow to identify receivers with orthogonal, and/or almost orthogonal, channel vectors in a very efficient way. ... hM of terminals 1, ... , M be quantized into code ... the matrix D = H-1 and assign vj = dj/lldjll,... more
... complexity, and allow to identify receivers with orthogonal, and/or almost orthogonal, channel vectors in a very efficient way. ... hM of terminals 1, ... , M be quantized into code ... the matrix D = H-1 and assign vj = dj/lldjll, where & are columns of D. For transmitting scalar symbols si ...
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Research Interests: Optics, Medical Imaging, Fiber Optics, Telecommunications, Photonics, and 15 moreSociety, Optical, Light, Code Generation, Optical physics, Reed Solomon Codes, Optical Modulator, Signal Detection, Decision Feedback, Forward Error Correction, Fiber Optic, Spectral Efficiency, Electrical And Electronic Engineering, Additive White Gaussian Noise, and Error Correction Code
Abstract The covering radius of a code tells us how far in the sense of Hamming distance an arbitrary word of the ambient space can be from the code. For a few decades this parameter has been widely studied. We estimate the covering... more
Abstract The covering radius of a code tells us how far in the sense of Hamming distance an arbitrary word of the ambient space can be from the code. For a few decades this parameter has been widely studied. We estimate the covering ratios of a code when the dual distance is known. We derive a new bound on covering radii of linear codes. It improves essentially on the previously known estimates in a certain wide range. We also study asymptotic bounds on the cardinality of constant weight codes
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AbstractWe study a combinatorial invariant of codes which counts the number of ordered pairs of codewords in all subcodes of restricted support in a code. This invariant can be expressed as a linear form of the components of the distance... more
AbstractWe study a combinatorial invariant of codes which counts the number of ordered pairs of codewords in all subcodes of restricted support in a code. This invariant can be expressed as a linear form of the components of the distance distribution of the code with binomial ...
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Research Interests: Information Theory, Information Geometry, Entropy, Reliability, Decoding, and 12 moreCodes, Lower Bound, Upper Bound, Gaussian noise, Minimum Distance Inference, Polynomials, Signal to Noise Ratio, Electrical And Electronic Engineering, Reliability Function, Asymptotic Properties, Gaussian Channel, and Code Rate
Research Interests: Approximation Algorithms, Binary Code, Channel Coding, Performance Analysis, Information Transfer, and 14 moreIterative Decoding, Mutual Information, Decoding, Transfer Function, Evolutionary Algorithm, Belief Propagation, Information Analysis, Gaussian Process, Asymptotic Behavior, Transfer Functions, Electrical And Electronic Engineering, Awgn, Additive White Gaussian Noise, and Gaussian approximation
ABSTRACT Massive multiple-input multiple-output (MIMO) wireless communications refers to the idea equipping cellular base stations (BSs) with a very large number of antennas, and has been shown to potentially allow for orders of magnitude... more
ABSTRACT Massive multiple-input multiple-output (MIMO) wireless communications refers to the idea equipping cellular base stations (BSs) with a very large number of antennas, and has been shown to potentially allow for orders of magnitude improvement in spectral and energy efficiency using relatively simple (linear) processing. In this paper, we present a comprehensive overview of state-of-the-art research on the topic, which has recently attracted considerable attention. We begin with an information theoretic analysis to illustrate the conjectured advantages of massive MIMO, and then we address implementation issues related to channel estimation, detection and precoding schemes. We particularly focus on the potential impact of pilot contamination caused by the use of non-orthogonal pilot sequences by users in adjacent cells. We also analyze the energy efficiency achieved by massive MIMO systems, and demonstrate how the degrees of freedom provided by massive MIMO systems enable efficient single-carrier transmission. Finally, the challenges and opportunities associated with implementing massive MIMO in future wireless communications systems are discussed.
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Abstract: Traditional approaches in the analysis of downlink systems decouple the precoding and channel estimation problems. However, in cellular systems with mobile users, these two problems are in fact tightly coupled. In this paper,... more
Abstract: Traditional approaches in the analysis of downlink systems decouple the precoding and channel estimation problems. However, in cellular systems with mobile users, these two problems are in fact tightly coupled. In this paper, this coupling is ...
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Page 1. ◆ Performance Results for Digital Subscriber Line Precoders Phil Whiting, Alexei Ashikhmin, Sem Borst, Jean Jennen, Gerhard Kramer, Adriaan J. de Lind van Wijngaarden, and Miroslav Zˇivkovic Performance results ...