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#### On the sum-capacity and lattice-based transmission strategies for state-dependent Gaussian interference channel

, Article IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC ; 2012 , Pages 1944-1948 ; 9781467325691 (ISBN) ; Behroozi, H ; Sharif University of Technology
2012

Abstract

In this work, we consider an additive state-dependent Gaussian interference channel (ASD-GIC) where there is a common additive interference, known to both transmitters but not to the receivers. First, we obtain an outer bound on the sum-capacity for the asymptotic case where the interference is assumed to be Gaussian variable with unbounded variance. This asymptotic case has been referred to as the "strong interference" in [1]. By applying a lattice-based coding scheme, an achievable rate-region is provided. Under some conditions, which depend on the noise variance and channel power constraints, this achievable sum-rate region meets the outer bound and therefore lattice codes can achieve the...

#### Application of Lattice Codes Over Channels with State

, M.Sc. Thesis Sharif University of Technology ; Behroozi, Hamid (Supervisor)
Abstract

Although in the network information theory most of results are based on applying random codes, one of the important challenges is to design linear structured codes that achieves the performance close to the performance of random codes. Recently, it is shown that lattice codes can be designed as good codes for quantization and also capacity-achieving in additive white Gaussian noise (AWGN) channel. Due to such a good performance, lattice codes can be designed properly and applied in various problems in network information theory.In this work, we study the performance of lattice codes for the following problems:1. Gaussian multiple access channel (MAC) with state: A joint source channel coding...

#### Two-way information exchange in two-level supply chain

, Article 2012 3rd International Conference on System Science, Engineering Design and Manufacturing Informatization, ICSEM 2012 ; Volume 2 , 2012 , Pages 92-95 ; 9781467309141 (ISBN) ; Haji, A ; Zare, A. G ; Behravesh, M ; Sharif University of Technology
2012

Abstract

The objective of the present study is to model and analyzing a two-level supply chain with reverse information exchange in which the manufacturer and the retailer are aware of the status of each other's stocks. To take advantages of this method of information exchange, manufacturers and retailers change their stock policies from traditional base-stock policy to a state-dependent two-level base-stock policy. Then, they change their ordering policy according to the other side's stock availability. Applying the mentioned method reduces the total cost of system as well as decreasing the average amount of manufacturer's inventory and improving the waiting time of walk-in customers

#### 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...

#### Control of a Camera Mounted on Satellite for High Resolution Photography

, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor) ; Khayyat, Ali Akbar (Co-Advisor)
Abstract

The huge capability of high resolution satellite imageries (HRSI), that includes spatial, spectral, temporal and radiometric resolutions as well as stereoscopic vision introduces them as a powerful new source for the Photogrammetric,Remote Sensing and GIS communities. High resolution data increases the need for higher accuracy of data modeling.The satellite orbit, position, attitude angles and interior orientation parameters have to be adjusted in the geometrical model to achieve optimal accuracy with the use of a minimum number of Ground Control Points (GCPs). In order to obtain high resolution and definition imaging for many applications including surveillance, target tracking, and...

#### Machine-Vision-Based Auotomatic Landing of Unmanned Helicopter

, M.Sc. Thesis Sharif University of Technology ; Saghafi, Fariborz (Supervisor)
Abstract

In this project an algorithm is designed for automatic landing of unmanned helicopter on a pad moving with six degrees of freedom. The designed controller is based on state dependent riccati equations (SDRE).by developing nonlinear mathematical model of helicopter and then converting this model to state dependent coefficient (SDC) form. A nonlinear compensator is added to controller to compensate effect of some nonlinear terms of model that are not able to translate and then state dependent riccati equations are solved.

The relative pose-estimation of landing pad is based on vision. Corner detection algorithm is used to identify and detect features by processing of image taken from...

The relative pose-estimation of landing pad is based on vision. Corner detection algorithm is used to identify and detect features by processing of image taken from...

#### Coordination in Cooperative Networks and Secret Key Agreement Using Common Information

, M.Sc. Thesis Sharif University of Technology ; Aref, Mohammad Reza (Supervisor)
Abstract

In order to utilize cooperative resources of a network, we have to investigate cooperative networks and strategies. Information theory, by introducing different concepts such as coordination and common information, gives us a suitable tool to study cooperative networks and using their resources. In this thesis, we investigate coordination and secret key agreement in cooperative networks. Our study consists of two parts. In the first part, we consider coordination and its applications in cooperative networks. For this purpose, we introduce the triangular multiterminal network as a proper model for studying empirical coordination in multiterminal networks and establish an inner and outer...

#### Key agreement over a state-dependent 3-receiver broadcast channel

, Article 2013 Iran Workshop on Communication and Information Theory ; 2013 ; 9781467350235 (ISBN) ; Bereyhi, A ; Salehkalaibar, S ; Aref, M. R ; Sharif University of Technology
2013

Abstract

In this paper, we consider the problem of secret key agreement in state-dependent 3-receiver broadcast channels. In the proposed model, there are two legitimate receivers, an eavesdropper and a transmitter where the channel state information is non-causally available at the transmitter. We consider two setups. In the first setup, the transmitter tries to agree on a common key with the legitimate receivers while keeping it concealed from the eavesdropper. Simultaneously, the transmitter agrees on a private key with each of the legitimate receivers that needs to be kept secret from the other legitimate receiver and the eavesdropper. For this setup, we derive inner and outer bounds on the...

#### On the achievable rate region of a state-dependent MAC with cooperating encoders

, Article 2012 Swedish Communication Technologies Workshop, Swe-CTW 2012 ; 2012 , Pages 48-52 ; 9781467347631 (ISBN) ; Khormuji, M. N ; Skoglund, M ; Aref, M. R ; Sharif University of Technology
2012

Abstract

The two-user discrete memoryless state-dependent multiple-access channel with cooperating encoders is considered. It is assumed that the channel is controlled with two independent states such that each of the channel state information is noncausally available at one encoder. Moreover, based on the intrinsic characteristic of wireless networks, it is assumed that each encoder strictly causally receive a noisy version of the transmitted signal of the other encoder. Hence, the encoders can cooperate in transmitting the message to the receiver. An achievable rate region for the channel is derived by use of rate splitting, block Markov encoding and Gelfand-Pinsker multilevel encoding along with...

#### Lattice coding for multiple access channels with common message and additive interference

, Article 2012 IEEE Information Theory Workshop, ITW 2012 ; 2012 , Pages 412-416 ; 9781467302234 (ISBN) ; Emadi, M. J ; Davoodi, A. G ; Aref, M. R ; Sharif University of Technology
2012

Abstract

In this paper, lattice based coding is used over two-user Gaussian state-dependent multiple access channel with common message for two channel models. First, it is assumed that the additive channel interference is noncausally known at both encoders. Exploiting a lattice encoding and decoding scheme, the effect of the interference is completely removed and the capacity region is achieved. Then, the multiple access channel with two additive interferences is considered in the case, where each interference is known noncausally to the associated transmitter. A pure lattice based encoding and decoding structure is proposed and an inner bound on the capacity region is derived which is valid for the...

#### State-dependent relay cchannel with private messages with partial causal and non-causal channel state information

, Article IEEE International Symposium on Information Theory - Proceedings, 13 June 2010 through 18 June 2010, Austin, TX ; 2010 , Pages 634-638 ; 21578103 (ISSN) ; 9781424469604 (ISBN) ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
2010

Abstract

In this paper, we introduce a discrete memoryless State-Dependent Relay Channel with Private Messages (SD-RCPM) as a generalization of the state-dependent relay channel. We investigate two main cases: SD-RCPM with non-causal Channel State Information (CSI), and SD-RCPM with causal CSI. In each case, it is assumed that partial CSI is available at the source and relay. For non-causal case, we establish an achievable rate region using Gel'fand-Pinsker type coding scheme at the nodes informed of CSI, and Compress-and-Forward (CF) scheme at the relay. Using Shannon's strategy and CF scheme, an achievable rate region for causal case is obtained. As an example, the Gaussian version of SD-RCPM is...

#### State-dependent Gaussian Z-interference channel: New results

, Article Proceedings of 2014 International Symposium on Information Theory and Its Applications, ISITA 2014 ; 26- 29 October , 2014 , pp. 468-472 ; ISBN: 9784885522925 ; Behroozi, H ; Sharif University of Technology
Abstract

A class of Gaussian Z-interference channels with state is investigated in the regime of high state power in which two transmitters communicate two independent messages through a 'dirty' Z-interference channel. Transmitter 1 (primary user) interferes with receiver 2 while transmitter 2 (secondary user) does not interfere with receiver 1. In addition, receiver 2 suffers from a random state sequence which is non-causally known only at transmitter 1. For this setup, which is also investigated by Duan et al. in [1], first we characterize the capacity region for the deterministic case and then by the obtained insight from analyzing the deterministic case, we establish sufficient conditions under...

#### On the secrecy of the cognitive interference channel with partial channel states

, Article Transactions on Emerging Telecommunications Technologies ; Volume 27, Issue 11 , 2016 , Pages 1472-1485 ; 21615748 (ISSN) ; Seyfe, B ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
Wiley Blackwell
2016

Abstract

The secrecy problem in the state-dependent cognitive interference channel is considered in this paper. In our model, there are a primary and a secondary (cognitive) transmitter–receiver pairs, in which the cognitive transmitter has the message of the primary one as side information. In addition, the channel is affected by two channel state sequences, which are known at the cognitive transmitter and the corresponding receiver, separately. The cognitive transmitter should cooperate with the primary one, and it wishes to keep its message secure at the primary receiver. The achievable equivocation-rate regions for this channel are derived using two approaches: the binning scheme coding and...

#### Compress-and-forward strategy for the relay channel with causal state information

, Article IEEE Information Theory Workshop, ITW 2009, 11 October 2009 through 16 October 2009 ; 2009 , Pages 426-430 ; 9781424449835 (ISBN) ; Akhbari, B ; Aref, M. R ; Sharif University of Technology
Abstract

In this paper, we study a state-dependent relay channel where perfect Channel State Information (CSI) is causally known to transmitters in both symmetric and asymmetric manner. So, three different setups are investigated in which causal CSI is available: 1) at the relay only, 2) at the source only and 3) both at the source and the relay nodes. In each situation, we obtain the lower bound on the capacity (achievable rate) for the general discrete memoryless case. The lower bounds are derived based on Shannon's strategy where CSI is known, and Compress-and-Forward (CF) Strategy at the relay

#### State-dependent multiple access relay channel with cooperating transmitters

, Article 2018 Iran Workshop on Communication and Information Theory, IWCIT 2018, 25 April 2018 through 26 April 2018 ; 2018 , Pages 1-6 ; 9781538641491 (ISBN) ; Mirmohseni, M ; Seyfe, B ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018

Abstract

In this paper, we consider a state-dependent multiple access relay channel (MARC) with two-way cooperation at transmitters, in which the transmitters cooperate with each other over two limited-rate channels. We derive an achievable rate region for this channel by using block-Markov superposition coding, and double binning techniques. In our proposed scheme, the relay decodes only parts of the messages which are shared between the transmitters. © 2018 IEEE

#### Cooperative relay-broadcast channels with causal channel state information

, Article 2009 IEEE International Symposium on Information Theory, ISIT 2009, Seoul, 28 June 2009 through 3 July 2009 ; 2009 , Pages 1174-1178 ; 21578102 (ISSN); 9781424443130 (ISBN) ; Akhbari, B ; Mirrnohseni, M ; Aref, M. R ; Sharif University of Technology
2009

Abstract

In this paper, we consider partially and fully cooperative state-dependent relay broadcast channels with perfect causal Channel State Information (CSI). For these two channels, we study three different situations: 1) both the source and the relay nodes have access to perfect CSI, 2) perfect CSI is only known to the relay nodes, 3) perfect CSI is only available at the source node. In each situation we obtain the capacity region for a degraded version of the channel. Our work subsumes previously obtained results for the degraded broadcast and relay channels with perfect causal CSI. © 2009 IEEE

#### Modeling the behavior of contending opportunistic cognitive radios

, Article 2007 IEEE International Conference on Signal Processing and Communications, ICSPC 2007, Dubai, 14 November 2007 through 27 November 2007 ; 2007 , Pages 720-723 ; 9781424412365 (ISBN) ; Ashtiani, F ; Hassani, S. H ; Tootoonchi, P ; Sharif University of Technology
2007

Abstract

In this paper, we propose a new model to evaluate the behavior of cognitive radios (CRs). In this model, we consider a specific number of primary users having independent probabilistic on-off behavior. In addition, a specific number of opportunistic cognitive radios in saturation mode is assumed. We consider contention for CRs in order to occupy an inactive primary channel independently according to a simple MAC scheme. Our model is based on a closed BCMP state-dependent queueing network. We map contention of the CRs and the behavior of primary users on suitable parameters of the queueing network. By solving the network, we obtain the steady state behavior of CRs, then we find the efficient...

#### Achievable rate regions for relay channel with private messages with states known at the source

, Article ; Proceedings 2010 IEEE International Conference on Information Theory and Information Security, ICITIS 2010, 17 December 2010 through 19 December 2010 , 2010 , Pages 1080-1087 ; 9781424469406 (ISBN) ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
Abstract

In this paper, we consider State-Dependent Relay Channel with Private Messages (SD-RCPM) as a generalization of the state-dependent relay channel, where the relay is both a source and a sink of data. We assume that the channel state is known only to the source and investigate two main cases: SD-RCPM with non-causal Channel State Information (CSI), and SD-RCPM with causal CSI. For non-causal case, we propose a coding scheme based on Gel'fand-Pinsker type coding at the source which is informed of CSI, and Decode-and-Forward (DF) scheme at the relay. Using Shannon's strategy and DF scheme, we also propose a coding strategy for the causal case. Based on these coding strategies, we derive new...

#### Finding an optimal core on a tree network with M/G/c/c state-dependent queues

, Article Mathematical Methods of Operations Research ; 2018 ; 14322994 (ISSN) ; Fathali, J ; Smith, J. M. G ; Mahdavi Amiri, N ; Sharif University of Technology
Springer Verlag
2018

Abstract

We consider the stochastic queue core problem on a tree network. Our aim is to find an optimal path on a tree network subject to the average travel time of particles moving along the tree for service given by a server traversing along the optimal path. We assume that particles originating at a node on a tree network request their demands for service randomly and the server is modeled first by an M/M/1 and then by an M/G/1 queue using the FIFO discipline. We consider that all paths along which the particles travel are modeled with an M/G/c/c state-dependent queue with the particles being independent of each other having demands according to the Poisson distribution. Two algorithms are...

#### Finding an optimal core on a tree network with M/G/c/c state-dependent queues

, Article Mathematical Methods of Operations Research ; Volume 89, Issue 1 , 2019 , Pages 115-142 ; 14322994 (ISSN) ; Fathali, J ; Smith, J. M. G ; Mahdavi Amiri, N ; Sharif University of Technology
Springer Verlag
2019

Abstract

We consider the stochastic queue core problem on a tree network. Our aim is to find an optimal path on a tree network subject to the average travel time of particles moving along the tree for service given by a server traversing along the optimal path. We assume that particles originating at a node on a tree network request their demands for service randomly and the server is modeled first by an M/M/1 and then by an M/G/1 queue using the FIFO discipline. We consider that all paths along which the particles travel are modeled with an M/G/c/c state-dependent queue with the particles being independent of each other having demands according to the Poisson distribution. Two algorithms are...