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gaussian-multiple-access-channel
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On the optimal performance in asymmetric gaussian wireless sensor networks with fading
, Article IEEE Transactions on Signal Processing ; Volume 58, Issue 4 , 2010 , Pages 2436-2441 ; 1053587X (ISSN) ; Alajaji, F ; Linder, T ; Sharif University of Technology
2010
Abstract
We study the estimation of a Gaussian source by a Gaussian wireless sensor network (WSN) where L distributed sensors transmit noisy observations of the source through a fading Gaussian multiple access channel to a fusion center. In a recent work Gastpar, [ "Uncoded transmission is exactly optimal for a Simple Gaussian Sensor Network", IEEE Trans. Inf. Theory, vol. 54, no. 11, pp. 52475251, Nov. 2008] showed that for a symmetric Gaussian WSN with no fading, uncoded (analog) transmission achieves the optimal performance theoretically attainable (OPTA). In this correspondence, we consider an asymmetric fading WSN in which the sensors have differing noise and transmission powers. We first...
On reconstructing linear combinations of correlated gaussian sources over a MAC
, Article IEEE Communications Letters ; Volume 20, Issue 12 , 2016 , Pages 2450-2453 ; 10897798 (ISSN) ; Behroozi, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
In this letter, we study the joint source-channel coding problem of communicating the linear functions of correlated Gaussian sources over a Gaussian multiple access channel. In this setup, each transmitter observes one of two correlated sources. The receiver aims to reconstruct a linear combination of both correlated Gaussian sources within an average distortion level. For this setup, we first obtain a new lower bound on the achievable distortion and then, we propose a novel lattice-based hybrid transmission scheme and its achievable distortion is derived. We show that our proposed scheme can achieve the optimal distortion under some conditions
The generalized MAC with partial state and message cooperation
, Article IWCIT 2014 - Iran Workshop on Communication and Information Theory ; May , 2014 ; 978-1-4799-4878-9 ; Khormuji, M. N ; Skoglund, M ; Aref, M. R ; Sharif University of Technology
Abstract
We consider a two-user state-dependent generalized multiple access channel (GMAC) with correlated channel state information (CSI). It is assumed that the CSI is partially known at each encoder noncausally. We first present an achievable rate region using multi-layer Gelfand-Pinsker coding with partial state and message cooperation between the encoders. We then specialize our result to a Gaussian GMAC with additive interferences that are known partially at each encoder. We show that the proposed scheme can remove the common part known at both encoders and also mitigate a significant part of the independent interference via state cooperation when the feedback links are strong. Thus, the...
Transmitting Correlated Gaussian Sources over a Gaussian Multiple-Access Channel
, M.Sc. Thesis Sharif University of Technology ; Hossein Khalaj, Babak (Supervisor) ; Behroozi, Hamid (Supervisor)
Abstract
This thesis considers the problem of communicating correlated Gaussian sources through a Gaussian multiple-access channel (MAC). A well known application of these problems is a sensor network. In a distributed sensor network, sensors measure the required parameters from the environment, encode and transmit them to a fusion center through a multiple-access channel. Then, the fusion center makes a decision about the environmental measured parameters by data processing on the received data from sensors. In these networks, one of the main concerns is the power limitation at sensors. As a result, we usually look for an encoding method that is not only simple but also has a nearly optimal...
Achievable rate regions for dirty tape channels and "joint writing on dirty paper and dirty tape"
, Article 2010 IEEE Information Theory Workshop, ITW 2010 - Proceedings, 30 August 2010 through 3 September 2010 ; 2010 ; 9781424482641 (ISBN) ; Akhbari, B ; Aref, M. R ; Sharif University of Technology
Abstract
We consider the Gaussian Dirty Tape Channel (DTC) Y=X+S+Z, where S is an additive Gaussian interference known causally to the transmitter. The general expression maxPU, f(.), X=f(U,S) I(U;Y) is proposed for the capacity of this channel. For linear assignment to f(.), i.e., X=U-βS, this expression leads to the compensation strategy proposed previously by Willems to obtain an achievable rate for the DTC. We show that linear assignment to f(.) is optimal under the condition that there exists a real number β* such that the pair (X+β*S, U) is independent of the interference S. Furthermore, by applying a time-sharing technique to the achievable rate derived by linear assignment to f (.), an...
Harnessing Interference in Cooperative Communication Networks
, Ph.D. Dissertation Sharif University of Technology ; Nasiri-Kenari, Masoumeh (Supervisor)
Abstract
The compute-and-forward (CMF) method has shown a great promise as an innovative approach to exploit interference towards achieving higher network throughput. Here, instead of recovering single messages, the relays attempt to reliably decode (compute) and pass an integer linear combination of the transmitted messages, referred to as an equation, to the destination. By receiving sufficient equations,the destination can solve the linear equation system to recover the desired messages.Two main challenges of the CMF methods are the computational complexity and the rank failure problem at the destination. In this thesis, to decrease the implementation as well as the computational complexity of the...
On distributed transmission of remote correlated Gaussian sources over an orthogonal Gaussian multiple-access channel
, Article 2016 8th International Symposium on Telecommunications, IST 2016, 27 September 2016 through 29 September 2016 ; 2017 , Pages 245-250 ; 9781509034345 (ISBN) ; Behroozi, H ; Khalaj, B. H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
In this paper, we consider the problem of sending a bivariate correlated Gaussian source through a two-user Gaussian orthogonal multiple-access channel (MAC), where each encoder observes a noisy version of one of the source components, and the receiver aims at reconstructing each source component. The estimation quality is measured by mean-squared error (MSE) distortion criterion. Different components of the source have their own fidelity requirements instead of total or average distortion measure. It is easy to verify that for this problem, digital communication has an optimal performance. However, it is not explicit that when there is a constraint on the total power budget, what power...