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wavelength-division-multiplexing
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Quantum Key Distribution in Quantum Networks
, Ph.D. Dissertation Sharif University of Technology ; Salehi, Jawad (Supervisor)
Abstract
With the rapid development of communication technology, the importance of information security is growing daily. Data Encryption, as one of the most important tools of secure communication, has attracted a lot of attention. Most conventional cryptography methods are based on computational complexity assumptions. Hence, they are threatened by computational power enhancements. One of the most important approaches of cryptography that does not have this drawback is quantum cryptography. The unconditional security of this method has been proved by laws of quantum mechanics. One application of quantum cryptography is quantum key distribution that enables secret key exchange between two users. The...
Time-domain split-step method with variable step-sizes in vectorial pulse propagation by using digital filters
, Article Optics Communications ; Volume 283, Issue 12 , June , 2010 , Pages 2518-2524 ; 00304018 (ISSN) ; Mehrany, K ; Sharif University of Technology
2010
Abstract
Finite impulse response (FIR) and infinite impulse response (IIR) digital filters are proposed to allow for time-domain simulation of optical pulse propagation by using the operator-splitting technique. These filters simulate polarization mode dispersion and chromatic dispersion effects with acceptable accuracy in time-domain. An analytical relation between the coefficients of these filters and the simulation step-size is established to accommodate the possibility of carrying out the time-domain split-step method with variable split-step length at virtually no computational burden. The superiority of the proposed method over the conventional frequency-domain technique is particularly...
Survivability performance evaluation of WDM networks with wavelength converters
, Article Photonic Network Communications ; Volume 11, Issue 1 , 2006 , Pages 15-27 ; 1387974X (ISSN) ; Jahangir, A. H ; Al-Zahrani, F. A ; Jayasumana, A. P ; Sharif University of Technology
2006
Abstract
Network Survivability is defined as the ability of a network to support the committed Quality of Services (QoS) continuously in the presence of different failure scenarios. Both availability and performance degradation of a system in presence of failure are integral components of survivability evaluation. Therefore, a composite model is presented for network survivability that includes system availability analysis to find out the cost due to system downtime, and system failure impact analysis to find out the transient performance degradation when failure occurs. A new analytical technique is presented to evaluate the excess loss due to failure (ELF) as the transient performance degradation...
Scalable architecture for wavelength-switched optical NoC with multicasting capability
, Article Proceedings - 13th Euromicro Conference on Digital System Design: Architectures, Methods and Tools, DSD 2010, 1 September 2010 through 3 September 2010, Lille ; 2010 , Pages 398-403 ; 9780769541716 (ISBN) ; Shafaei, A ; Hessabi, S ; Sharif University of Technology
2010
Abstract
This paper proposes a novel all-optical router as a building block for a scalable wavelength-switched optical NoC. The proposed optical router, named as AOR, performs passive routing of optical data streams based on their wavelengths. Utilizing wavelength routing method, AOR eliminates the need for electrical resource reservation and the corresponding latency and area overheads. Taking advantage of Wavelength Division Multiplexing (WDM) technique, the proposed architecture is capable of data multicasting, concurrent with unicast data transmission, with high bandwidth and low power dissipation, without imposing noticeable area and latency overheads. Comparing AOR against previously proposed...
Resonant tunneling based filter design using legendre polynomial expansion
, Article Photonics North 2006, Quebec City, QB, 5 June 2006 through 8 June 2006 ; Volume 6343 II , 2006 ; 0277786X (ISSN) ; 0819464287 (ISBN); 9780819464286 (ISBN) ; Mehrany, K ; Rashidian, B ; Akbari, M ; Sharif University of Technology
2006
Abstract
In this paper optical filters based on photonic resonant tunneling effect are analyzed by using the polynomial expansion method. Amplitude and phase response together with their dependency on the physical parameters of the filters are also investigated. These steep-edge filters show low insertion loss amplitude response, and linear phase variation in their passband, a suitable feature for WDM and DWDM applications where constant time delay and dispersion free devices are needed. Two kinds of filters, namely discrete level and continuous profile filters are introduced. These structures can be analyzed and designed by using Transfer Matrix Method. However, this approach suffers from inaccuracy...
QuT: A low-power optical network-on-chip
, Article Proceedings - 2014 8th IEEE/ACM International Symposium on Networks-on-Chip, NoCS 2014, 17 September 2014 through 19 September 2014 ; 2015 , Pages 80-87 ; 9781479953479 (ISBN) ; Enright Jerger, N ; Hessabi, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
To enable the adoption of optical Networks-on-Chip (NoCs) and allow them to scale to large systems, they must be designed to consume less power and energy. Therefore, optical NoCs must use a small number of wavelengths, avoid excessive insertion loss and reduce the number of microring resonators. We propose the Quartern Topology (QuT), a novel low-power all-optical NoC. We also propose a deterministic wavelength routing algorithm based on Wavelength Division Multiplexing that allows us to reduce the number of wavelengths and microring resonators in optical routers. The key advantages of QuT network are simplicity and lower power consumption. We compare QuT against three alternative...
Power efficient nanophotonic on-chip network for future large scale multiprocessor architectures
, Article Proceedings of the 2011 IEEE/ACM International Symposium on Nanoscale Architectures, NANOARCH 2011, 8 June 2011 through 9 June 2011, San Diego, CA ; 2011 , Pages 114-121 ; 9781457709944 (ISBN) ; Hessabi, S ; Sharif University of Technology
2011
Abstract
This paper proposes new architectures for data and control planes in a nanophotonic networks-on-chip (NoC) with the key advantages of scalability to large scale networks, constant node degree, and simplicity. Moreover, we propose a minimal deterministic routing algorithm for the data network which leads to small and simple photonic switches. Built upon the proposed novel topology, we present a scalable all-optical NoC, referred to as 2D-HERT, which offers passive routing of optical data streams based on their wavelengths. Utilizing wavelength routing method, Wavelength Division Multiplexing (WDM) technique, and a new all-optical control architecture, our proposed optical NoC eliminates the...
Orthogonal frequency division multiplexed quantum key distribution in the presence of Raman noise
, Article Proceedings of SPIE - The International Society for Optical Engineering, 5 April 2016 through 7 April 2016 ; Volume 9900 , 2016 ; 0277786X (ISSN) ; 9781510601451 (ISBN) ; Razavi, M ; Salehi, J. A ; Sharif University of Technology
SPIE
2016
Abstract
In this paper, we investigate the performance of orthogonal frequency division multiplexed quantum key distribution (OFDM-QKD) in an integrated quantum-classical wavelength-division-multiplexing system. The presence of an intense classical signal alongside the quantum one generates Raman background noise. Noise reduction techniques should, then, be carried out at the receiver to suppress this crosstalk noise. In this work, we show that OFDM-QKD enables efficient filtering, in time and frequency domains, making it an attractive solution for the high-rate links at the core of quantum-classical networks
Orthogonal frequency-division multiplexed quantum key distribution
, Article Journal of Lightwave Technology ; Volume 33, Issue 23 , September , 2015 , Pages 4687-4698 ; 07338724 (ISSN) ; Razavi, M ; Salehi, J. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
We propose orthogonal frequency-division multiplexing (OFDM), as a spectrally efficient multiplexing technique, for quantum key distribution at the core of trusted-node quantum networks. Two main schemes are proposed and analyzed in detail, considering system imperfections, specifically, time misalignment issues. It turns out that while multiple service providers can share the network infrastructure using the proposed multiplexing techniques, no gain in the total secret key generation rate is obtained if one uses conventional passive all-optical OFDM decoders. To achieve a linear increase in the key rate with the number of channels, an alternative active setup for OFDM decoding is proposed,...
Optimal wavelength allocation in hybrid quantum-classical networks
, Article European Signal Processing Conference, 28 August 2016 through 2 September 2016 ; Volume 2016-November , 2016 , Pages 483-487 ; 22195491 (ISSN) ; 9780992862657 (ISBN) ; Razavi, M ; Salehi, J. A ; Sharif University of Technology
European Signal Processing Conference, EUSIPCO
2016
Abstract
An efficient method for optimal allocation of wavelengths in a hybrid dense-wavelength-division-multiplexing system, carrying both quantum and classical data, is proposed. The transmission of quantum bits alongside intense classical signals on the same fiber faces major challenges arising from the background noise generated by classical channels. Raman scattering, in particular, is shown to have detrimental effects on the performance of quantum key distribution systems. Here, by using a nearly optimal wavelength allocation technique, we minimize the Raman induced background noise on quantum channels, hence maximize the achievable secret key generation rate for quantum channels. It turns out...
Multiservice provisioning and quality of service guarantee in WDM optical code switched GMPLS core networks
, Article Journal of Lightwave Technology ; Volume 27, Issue 12 , 2009 , Pages 1754-1762 ; 07338724 (ISSN) ; Salehi, J. A ; Sharif University of Technology
2009
Abstract
In this paper, we propose a new scheme to provide multiservice transmission on generalized multiprotocol label switching (GMPLS) networks using optical code-division multiplexing (OCDM) in each wavelength of a wavelength-division multiplexing system. To provide multiservice transmission in a typical GMPLS network, we propose to classify the fiber bandwidth into a number of waveband and consider the wavelengths of each waveband for a specific class-of-service such that the corresponding codes to be used are designed based on the characteristics of the class-of-service. The traffic behavior of the network is examined using Erlang's model, and the probability density functions (PDF) of the...
Multi-service provisioning and quality of service (QOS) guarantee in WDM optical code switched GMPLS core networks
, Article IEEE Journal of Lightwave Technology ; Vol. 27, No. 12, PP. 1754-1762 , Jun. 2009 ; Salehi, J. A ; Sharif University Of Technology
Abstract
In this paper, we propose a new scheme to provide multiservice transmission on generalized multiprotocol label switching (GMPLS) networks using optical code-division multiplexing (OCDM) in each wavelength of a wavelength-division multiplexing system. To provide multiservice transmission in a typical GMPLS network, we propose to classify the fiber bandwidth into a number of waveband and consider the wavelengths of each waveband for a specific class-of-service such that the corresponding codes to be used are designed based on the characteristics of the class-of-service. The traffic behavior of the network is examined using Erlang's model, and the probability density functions (PDF) of the...
Multi-rate and multi-quality of service passive optical network based on hybrid WDM/OCDM system [electronic resource]
, Article IEEE Communications Magazine ; February 2011, Volume 49, Issue 2, PP. S39-S44 ; Salehi, J. A ; Sharif University of Technology
Abstract
In this article we present a new scheme to support multirate and multi-quality-of-service transmission in passive optical networks based on a hybrid wavelength-division multiplexing/optical code-division multiplexing scheme. The idea is to use multilength variable-weight optical orthogonal codes as signature sequences of a hybrid WDM/OCDM system. To provide the requested classes of service, the code weight and code length of MLVW-OOCs are designed based on the characteristics of the requested classes of service. In order to mitigate multiple access interference, we propose to utilize a multilevel signaling technique and interference remover structure based on advanced optical logic gate...
Multirate and multi-quality-of-service passive optical network based on hybrid WDM/OCDM system
, Article IEEE Communications Magazine ; Volume 49, Issue 2 , February , 2011 , Pages S39-S44 ; 01636804 (ISSN) ; Salehi, J. A ; Sharif University of Technology
2011
Abstract
In this article we present a new scheme to support multirate and multi-quality-of-service transmission in passive optical networks based on a hybrid wavelength-division multiplexing/ optical code-division multiplexing scheme. The idea is to use multilength variable-weight optical orthogonal codes as signature sequences of a hybrid WDM/OCDM system. To provide the requested classes of service, the code weight and code length of MLVW-OOCs are designed based on the characteristics of the requested classes of service. In order to mitigate multiple access interference, we propose to utilize a multilevel signaling technique and interference remover structure based on advanced optical logic gate...
Label swapping in all-optical networks using tunable fiber Bragg grating arrays
, Article 8th International Conference Advanced Communication Technology, ICACT 2006, Phoenix Park, 20 February 2006 through 22 February 2006 ; Volume 2 , 2006 , Pages 1429-1431 ; 8955191294 (ISBN); 9788955191295 (ISBN) ; Behnia, F ; Fatehi, M. T ; Sharif University of Technology
IEEE Computer Society
2006
Abstract
In this paper we use tunability of FBG to introduce a novel device for optically reading, writing or modifying the low-speed label(s). We utilize tunable FBG arrays as concurrent label modulating (multiplexing) elements. This second-level intensity modulation is used to send signaling messages between nodes of WDM networks. The fiber optic small-signal modulator is formulated, and its behavior is compared with the published reports
Higher-order four-wave mixing modeling in DWDM networks
, Article Physica Scripta, Belgrade ; Volume T157 , 15 November , 2013 ; 02811847 (ISSN) ; Noshad, M ; Sharif University of Technology
2013
Abstract
In this paper, we derive a theoretical model for the higher-order four-wave mixing (FWM) power in wavelength division multiplexing networks with non-zero dispersion shifted fibers for the first time. We have investigated the higher-order FWM power theoretically and by numerical simulations. Dividing the fiber into a finite number of elements and applying the boundary conditions allow us to derive an expression for the second-order power penalty. At the end of each element, we derive the first-order FWM power for all wavelengths and use these values to calculate the second-order FWM power in the next element. Consequently, for each channel we can compute the total second-order FWM power...
Efficient optical resource allocation and QoS differentiation in optical burst switching networks utilizing hybrid WDM/OCDM
, Article Journal of Lightwave Technology ; Volume 30, Issue 15 , 2012 , Pages 2427-2441 ; 07338724 (ISSN) ; Salehi, J. A ; Sharif University of Technology
2012
Abstract
In this paper, a QoS differentiation framework is proposed for an optical burst switching (OBS) multiservice network. Furthermore, hybrid wavelength division multiplexing and optical code division multiplexing (WDM/OCDM) scheme is used to mitigate the blocking probability of OBS networks. In our study, the measurement criteria of QoS are the blocking probability, OBS network delay, transmission rate, and OCDM probability of error. In order to increase the bandwidth efficiency and control the multiplexing interference effect of OCDM, an advanced optical resource allocation strategy is introduced. The proposed strategy is also compared with a conventional strategy based on random allocation....
Dynamic 3D hand gesture recognition by learning weighted depth motion maps
, Article IEEE Transactions on Circuits and Systems for Video Technology ; 12 July , 2018 , Pages: 1-1 ; 15582205 (Electronic ISSN) ; Asadi Aghbolaghi, M ; Kasaei, S ; Escalera, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
Hand gesture recognition from sequences of depth maps is a challenging computer vision task because of the low inter-class and high intra-class variability, different execution rates of each gesture, and the high articulated nature of human hand. In this paper, a multilevel temporal sampling (MTS) method is first proposed that is based on the motion energy of key-frames of depth sequences. As a result, long, middle, and short sequences are generated that contain the relevant gesture information. The MTS results in increasing the intra-class similarity while raising the inter-class dissimilarities. The weighted depth motion map (WDMM) is then proposed to extract the spatio-temporal...
Dynamic 3D hand gesture recognition by learning weighted depth motion maps
, Article IEEE Transactions on Circuits and Systems for Video Technology ; Volume 29, Issue 6 , 2019 , Pages 1729-1740 ; 10518215 (ISSN) ; Asadi Aghbolaghi, M ; Kasaei, S ; Escalera, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Hand gesture recognition (HGR) from sequences of depth maps is a challenging computer vision task because of the low inter-class and high intra-class variability, different execution rates of each gesture, and the high articulated nature of the human hand. In this paper, a multilevel temporal sampling (MTS) method is first proposed that is based on the motion energy of keyframes of depth sequences. As a result, long, middle, and short sequences are generated that contain the relevant gesture information. The MTS results in increasing the intra-class similarity while raising the inter-class dissimilarities. The weighted depth motion map (WDMM) is then proposed to extract the spatiotemporal...
Design of an expert system to estimate cost in an automated jobshop manufacturing system
, Article 40th International Conference on Computers and Industrial Engineering: Soft Computing Techniques for Advanced Manufacturing and Service Systems, CIE40 2010, 25 July 2010 through 28 July 2010, Awaji ; 2010 ; 9781424472956 (ISBN) ; Mahdavi Amiri, N ; Sharif University of Technology
2010
Abstract
We propose a cost estimation model based on a fuzzy rule back-propagation network (BPN), configuring the rules to estimate the cost under uncertainty. A multiple linear regression analysis is applied to analyze the rules and identify the effective rules for cost estimation. Then, using a dynamic programming approach we determine the optimal path in the manufacturing network. Finally, an application of this model is illustrated through a numerical example showing the effectiveness of the proposed model for solving the cost estimation problem under uncertainty