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Robust relay beamforming against jamming attack
, Article IEEE Communications Letters ; Volume 22, Issue 2 , February , 2018 , Pages 312-315 ; 10897798 (ISSN) ; Ahmadian Attari, M ; Amiri, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
In this letter, we surpass the jamming effect and also estimate the jamming channel state information by using the Kalman filtering approach. Furthermore, we design a closed-form beamforming weight for maximizing the achievable rate subject to the condition that the total relays power transmission would be below a predefined threshold level, which is formulated as a quadratically constrained quadratic program. Simulation results show the efficient performance of the proposed method for different destruction powers of the jammer by achieving the Cramér-Rao lower bound. © 1997-2012 IEEE
Iterative multiuser receiver for coded MC-FH multiple access systems in the presence of partial-band interference
, Article 2004 IEEE 60th Vehicular Technology Conference, VTC2004-Fall: Wireless Technologies for Global Security, Los Angeles, CA, 26 September 2004 through 29 September 2004 ; Volume 60, Issue 3 , 2004 , Pages 1899-1903 ; 15502252 (ISSN) ; Nasiri Kenari, M ; Sharif University of Technology
2004
Abstract
In this paper, we consider an iterative multiuser receiver for the coded MC-FH system, first introduced in [4], in the presence of partial-band interference. The structure of the receiver consists of two principal parts: multiuser soft input soft output (SISO) detector and SISO channel decoder. When the channel is under the attack of jamming, for optimum detection we propose to add a jamming estimator to multiuser SISO detector. So, the new SISO multiuser detector consists of multiuser likelihood calculator (MULC) and iterative jamming estimator (JE). The numerical results show that the proposed receiver works quite well compared to the ideal receiver which has the perfect channel state...
Performance comparison of coherent and non-coherent multicarrier frequency-hopping code division multiple-access systems
, Article 2004 IEEE 15th International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2004, Barcelona, 5 September 2004 through 8 September 2004 ; Volume 1 , 2004 , Pages 165-169 ; Nasiri Kenari, M ; Sharif University of Technology
2004
Abstract
In this paper, we evaluate and compare the multiuser performance of the multicarrier frequency-hopping (MCFH) CDMA system using coherent and non-coherent detections in AWGN and slowly frequency-selective Rayleigh fading channels in a downlink application. For fair comparison, we use BFSK modulation for both cases. Our numerical results indicate that in both AWGN and fading channels, the coherent detection sub-stantially outperforms the non-coherent detection. Furthermore, it has been realized that the performance enhancement due to the diversity order is only observable for coherent detection
Design and implementation of spectrally-encoded spread-time CDMA transceiver
, Article IEEE Communications Letters ; Vol. 18, issue. 5 , 2014 , pp. 741-744 ; ISSN: 10897798 ; Hosseinianfar, H ; Akhoundi F ; Yazdian, E ; Farhang, M ; Salehi, J. A ; Sharif University of Technology
Abstract
In this paper, we present and discuss the physical implementation and testing of a Spectrally-Encoded Spread-Time Code Devision Multiple Access (SE/ST-CDMA) transceiver. The proposed design is suitable for multiple-access and anti jamming wireless communication systems. The design and implementation takes into account the ability to automatically detect and mitigate tone jammers by altering the corresponding Gold sequence codes assigned uniquely to each user and setting the corresponding code's chip to zero. A simple real-time anti jamming mechanism capable of dealing with frequency hopping jammers is also proposed. The simulation results are provided in terms of Bit Error Rate (BER) versus...
Physical layer security in AF and CF relay networks with RF-energy harvesting
, Article 2017 14th International ISC (Iranian Society of Cryptology) Conference on Information Security and Cryptology, ISCISC 2017, 6 September 2017 through 7 September 2017 ; 2018 , Pages 86-92 ; 9781538665602 (ISBN) ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
Abstract
In this paper, we investigate the achievable secrecy rate in a relay channel where the source and the destination wish to keep the information confidential from an untrusted relay (potential eavesdropper). The relay has no energy supply, and harvests its required energy for relaying from its received signals. For radio-frequency (RF) Energy Harvesting (EH) at the relay, we adopt power splitting (PS) approach. We study the problem of achieving positive secrecy rates between the transmitter and the receiver while making use of an untrusted relay. Energy limitation at the relay makes the problem more interesting. Because, the relay must choose either to eavesdrop the signal to be able to decode...
Preventing the transmission of harmful cognitive radio users in the presence of primary users
, Article Proceedings - 2009 1st UK-India International Workshop on Cognitive Wireless Systems, UKIWCWS 2009, 11 December 2009 through 12 December 2009, New Delhi ; 2009 ; 9781457701832 (ISBN) ; Soleimanipour, M ; Sharif University of Technology
Abstract
A cognitive radio provides access to a licensed spectrum for unlicensed users opportunistically provided that they are not harmful for licensed users (primary users). We call a cognitive radio user (CR user) harmful, when it generates interference for primary users (PU) or occupies spectrum holes excessively. This paper discusses the spectrum management policy against harmful CR users. For this, we design a jammer signal which ruins transmission of harmful CR users and forces them to leave the spectrum without damaging the communication of PUs. This signal is designed using group subspace technique for both synchronous and asynchronous channels. Our simulation results show that the designed...
Multiuser performance comparisons of fast frequency hopping and multicarrier slow frequency hopping systems:Uncoded and coded schemes
, Article 2004 IEEE 60th Vehicular Technology Conference, VTC2004-Fall: Wireless Technologies for Global Security, Los Angeles, CA, 26 September 2004 through 29 September 2004 ; Volume 60, Issue 3 , 2004 , Pages 1894-1898 ; 15502252 (ISSN) ; Nasiri Kenari, M ; Sharif University of Technology
2004
Abstract
In this paper, we evaluate and compare the multiuser performance of the Fast Frequency-Hopping (FFH) and the MultiCarrier slow Frequency-Hopping (MC-FH) systems employing non-coherent detection for both uncoded and coded schemes in AWGN and slowly frequency-selective Rayleigh fading channels, based on Gaussian distribution assumption for the decision variable. Our numerical resulte indicate that with non-coherent detection, both systems show the same performance. However, the MC-FH system can be easily implemented using FFT algorithm. Furthermore with a slow hopping rate and high number of carriers, a coherent detection for the MC-FH system is feasible. Our results will indicate that the...
Robust relay beamforming against jamming attack
, Article IEEE Communications Letters ; 2017 ; 10897798 (ISSN) ; Ahmadian Attari, M ; Amiri, R ; Sharif University of Technology
Abstract
In this letter, we surpass the jamming effect and also estimate the jamming channel state information by using Kalman filtering (KF) approach. Furthermore, we design a closed-form beamforming weight for maximizing the achievable rate subject to the condition that the total relays power transmission would be below a predefined threshold level, which is formulated as a Quadratically Constrained Quadratic Program (QCQP). Simulation results show efficient performance of the proposed method for different destruction powers of jammer by achieving the Cramer Rao Lower Bound (CRLB). IEEE
Jamming-resilient frequency hopping-aided secure communication for internet-of-things in the presence of an untrusted relay
, Article IEEE Transactions on Wireless Communications ; Volume 19, Issue 10 , July , 2020 , Pages 6771-6785 ; Kuhestani, A ; Behroozi, H ; Ng, D. W. K ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
In this paper, we propose a light-weight jamming-resistant scheme for the Internet-of-Things (IoT) in 5G networks to ensure high-quality communication in a two-hop cooperative network. In the considered system model, a source communicates with a destination in the presence of an untrusted relay and a powerful multi-Antenna adversary jammer. The untrusted relay is an authorized necessary helper who may wiretap the confidential information. Meanwhile, the jammer is an external attacker who tries to damage both the training and transmission phases. Different from traditional frequency hopping spread spectrum (FHSS) techniques that require a pre-determined pattern between communicating nodes, in...
Jamming resistance capabilities of spectrally-phase encoded OCDMA communication systems with optimum and suboptimum (nonlinear two-photon-absorption) receiver structures[electronic resource]
, Article IEEE Journal of Lightwave Technology ; Vol. 27, No. 22, PP. 5010-5021, Nov. 15, 2009 ; Salehi, J.A ; Sharif University Of Technology
Abstract
In this paper, we study three types of jammers, namely, pulse-jammer, partial-band jammer, and follower-jammer, in a typical fiber-optic-based spectrally phase-encoded optical code division multiple-access (SPE-OCDMA) system. We analyze, mathematically, the effects of the aforementioned jammers on the performance of an SPE-OCDMA system for two scenarios, namely, ideal noiseless channel with an ideal optimum receiver and an ultrahigh-speed nonlinear receiver based on two-photon-absorption (TPA) in a noisy channel. Also, for each of the above cases, two types of modulation, namely, on-off keying (OOK) and two-code keying (2CK) are investigated and their system performances are compared. It is...
On AVCs with quadratic constraints
, Article IEEE International Symposium on Information Theory - Proceedings, Istanbul ; July , 2013 , Pages 271-275 ; 21578095 (ISSN); 9781479904464 (ISBN) ; Siavoshani, M. J ; Bakshi, M ; Jaggi, S ; IEEE; IEEE Information Theory Society ; Sharif University of Technology
2013
Abstract
In this work we study an Arbitrarily Varying Chanel (VC) with quadratic power constraints on the transmitter and a so-called 'oblivious' jammer (along with additional AWGN) under a maximum probability of error criterion, and no private randomness between the transmitter and the receiver. This is in contrast to similar AVC models under the average probability of error criterion considered in [1], [2], and models wherein common randomness is allowed [3] - these distinctions are important in some communication scenarios outlined below. We consider the regime where the jammer's power constraint is smaller than the transmitter's power constraint (in the other regime it is known no positive rate...
VHF-LB SDR phased array jamming resistant antenna
, Article ITST 2006 - 2006 6th International Conference on ITS Telecommunications, Proceedings, Chengdu, 21 June 2006 through 23 June 2006 ; 2006 , Pages 442-445 ; 0780395867 (ISBN); 9780780395862 (ISBN) ; Emadi, M ; Esmi, N ; Mousavi, M ; Nayebi, M. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2006
Abstract
Genetic algorithm for optimization of beam forming in linear array antenna is used. The goal is to achieve a -30 dB null depth in pattern, with null steering capability over the frequency band. The simulation result is -85 dB that the SuperNEC results accepted this result by -56 dB Null Depth. Software Define Radio (SDR) Technology and digital I/Q modulator are used to implement the system. © 2006 IEEE
A lightweight secure and resilient transmission scheme for the internet of things in the presence of a hostile jammer
, Article IEEE Internet of Things Journal ; Volume 8, Issue 6 , 2021 , Pages 4373-4388 ; 23274662 (ISSN) ; Kuhestani, A ; Wong, K. K ; Piran, M. J ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
In this article, we propose a lightweight security scheme for ensuring both information confidentiality and transmission resiliency in the Internet-of-Things (IoT) communication. A single-Antenna transmitter communicates with a half-duplex single-Antenna receiver in the presence of a sophisticated multiple-Antenna-Aided passive eavesdropper and a multiple-Antenna-Assisted hostile jammer (HJ). A low-complexity artificial noise (AN) injection scheme is proposed for drowning out the eavesdropper. Furthermore, for enhancing the resilience against HJ attacks, the legitimate nodes exploit their own local observations of the wireless channel as the source of randomness to agree on shared secret...
A new frequency hopping-aided secure communication in the presence of an adversary jammer and an untrusted relay
, Article 2020 IEEE International Conference on Communications Workshops, ICC Workshops 2020, 7 June 2020 through 11 June 2020 ; July , 2020 ; Kuhestani, A ; Ng, D. W. K ; Behroozi, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
The Internet-of-Things (IoT) spans various applications in healthcare filed, from smart wearable or implantable sensors to remote monitoring of elderly, and medical device networking. In this paper, a jamming-resistant scheme for the healthcare IoT is proposed to provide secure and reliable data transmission in a two-hop cooperative network, where a source communicates with a destination in the presence of an untrusted relay and an active adversary. The untrusted relay is an authorized necessary helper who may wiretap the confidential information, e.g., the secret measured data of a patient, while the jammer is an external attacker who tries to interrupt the communication. Different from...
A UHF-RFID transceiver with a blocker-canceller feedback and 30 dBm output power
, Article IEEE Transactions on Circuits and Systems I: Regular Papers ; Volume 60, Issue 11 , 2013 , Pages 3043-3054 ; 15498328 (ISSN) ; Rezaei, V. D ; Bakhtiar, M. S ; Sharif University of Technology
2013
Abstract
A single chip UHF-RFID transceiver front-end is presented. The chip was designed according to EPCglobal Class-1 Gen-2 and supports both ETSI and FCC requirements. The receiver front end is capable of rejecting self-jammers as large as 10 dBm with the aid of a feedback loop. The stability and the robustness of the loop and other system requirements are studied. A 30 dBm class-AB power amplifier (PA) with 28% PAE is also integrated on the chip. The pseudo differential architecture of the PA greatly reduces the injection of the signal into the substrate. A simple model is used to estimate the effect of the substrate noise injection by the PA on the receiving circuit modules and design guides...
A novel genetic-based resource allocation and cooperative node selection technique for physical layer security designs
, Article Wireless Personal Communications ; Volume 95, Issue 4 , 2017 , Pages 4733-4746 ; 09296212 (ISSN) ; Mosavi, M. R ; Behroozi, H ; Sharif University of Technology
Springer New York LLC
2017
Abstract
This paper presents a novel approach for power allocation and cooperative node selection to enhance physical layer security in presence of an eavesdropper in a wireless network. Our network consists of a source–destination pair and a number of cooperative nodes which can be used as relays to increase throughput at the destination, or as friendly jammers to confuse eavesdropper. First, we introduce a low complexity method, for which relay−jammer selection and power allocation are performed, simultaneously. Then, we propose self-adaptive genetic algorithm to solve the non-linear non-convex programing problem. Using the proposed method, the number of friendly jammers that ensure the secrecy...
A genetic approach in relay-jammer selection and power allocation for physical layer security
, Article 8th International Symposium on Telecommunications, IST 2016, 27 September 2016 through 29 September 2016 ; 2017 , Pages 374-379 ; 9781509034345 (ISBN) ; Mosavi, M. R ; Behroozi, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Node cooperation approaches improve physical layer security in wireless networks without applying data encryption. Selecting the appropriate nodes to cooperate as relays or friendly jammers, to degrade eavesdropper's link, is a challenging problem which has attracted a lot of attention in recent years. Various approaches, based on conventional exhaustive search, have been suggested for optimal relay-jammer selection and power allocation in the literature. The complexity of these methods is proportional to the number of intermediate nodes. As the number of intermediate nodes exceeds a specific bound, conventional exhaustive search appears infeasible due to high computational complexity. In...
Jamming resistance capabilities of spectrally phase encoded OCDMA communication systems with optimum and suboptimum (nonlinear two-photon-absorption) receiver structures
, Article Journal of Lightwave Technology ; Volume 27, Issue 22 , 2009 , Pages 5010-5021 ; 07338724 (ISSN) ; Salehi, J. A ; Sharif University of Technology
2009
Abstract
In this paper, we study three types of jammers, namely, pulse-jammer, partial-band jammer, and follower-jammer, in a typical fiber-optic-based spectrally phase-encoded optical code division multiple-access (SPE-OCDMA) system. We analyze, mathematically, the effects of the aforementioned jammers on the performance of an SPE-OCDMA system for two scenarios, namely, ideal noiseless channel with an ideal optimum receiver and an ultrahigh-speed nonlinear receiver based on two-photon-absorption (TPA) in a noisy channel. Also, for each of the above cases, two types of modulation, namely, ON-OFF keying (OOK) and two-code keying (2CK) are investigated and their system performances are compared. It is...
Outage performance in secure cooperative NOMA
, Article 2019 Iran Workshop on Communication and Information Theory, IWCIT 2019, 24 April 2019 through 25 April 2019 ; 2019 ; 9781728105840 (ISBN) ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Enabling cooperation in a NOMA system is a promising approach to improve its performance. In this paper, we study the cooperation in a secure NOMA system, where the legitimate users are distributed uniformly in the network and the eavesdroppers are distributed according to a homogeneous Poisson point process. We consider a cooperative NOMA scheme (two users are paired as strong and weak users) in two phases: 1) Direct transmission phase, in which the base station broadcasts a superposition of the messages, 2) Cooperation phase, in which the strong user acts as a relay to help in forwarding the messages of the weak user. We study the secrecy outage performance in two cases: (i) security of...
Secure transmission with covert requirement in untrusted relaying networks
, Article 9th International Symposium on Telecommunication, IST 2018, 17 December 2018 through 19 December 2018 ; 2019 , Pages 670-675 ; 9781538682746 (ISBN) ; Azmi, P ; Kuhestani, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, we investigate the problem of secure communication with covert requirement in untrusted relaying networks. Our considered system model contains one source, one destination, one untrusted relay, and one Willie. The untrusted relay tries to extract the information signal, while the goal of Willie is to detect the presence of the information signal transmitted by the source, in the current time slot. To overcome these two attacks, it is assumed that the destination and the source inject jamming signal to the network in phase I and phase II, respectively. Accordingly, the communication in our proposed system model is accomplished in two phases. In the first phase, when the source...