Loading...
Search for:
pseudo-randoms
0.006 seconds
Test data compression strategy while using hybrid-BIST methodology
, Article Proceedings of IEEE East-West Design and Test Symposium, EWDTS 2013, Rostov-on-Don ; Sept , 2013 ; 9781479920969 (ISBN) ; Tabandeh, M ; Haghbayan, M. H ; Sharif University of Technology
2013
Abstract
In this paper a strategy is proposed for compressing the test data while using concurrent hybrid-BIST methodologyfor testing SoCs. In the proposed method, in addition tousing BIST strategy for testing cores with deterministic sequential test patterns in an SoC( Without using scan chains), (ATE) is used for testing cores with deterministic test patterns through Test Access Mechanism (TAM) or functional bus. As will be shown in experimental results, this process compresses hybrid-BIST overall test patterns considerably that affects the overall Test Application Time (TAT) in comparison with pure deterministic, pure pseudo random, and combination of deterministic and pseudo random test patterns
Adaptive random puncturing based secure block turbo coding
, Article 2010 5th International Symposium on Telecommunications, IST 2010, 4 December 2010 through 6 December 2010 ; December , 2010 , Pages 216-220 ; 9781424481835 (ISBN) ; Payandeh, A ; Aref, M. R ; Sharif University of Technology
2010
Abstract
Reliability and security are two important subjects in modern digital communications. A secure channel coding scheme provides both of reliability and security in one process to combat problems in an unreliable and insecure channel. In this paper, a secure block turbo coding scheme will be proposed and analyzed. Security and reliability are based on pseudo-random puncturing. Simulation results show that this scheme has superior performance and high security
A novel architecture of pseudorandom dithered MASH digital delta-sigma modulator with lower spur
, Article Journal of Circuits, Systems and Computers ; Volume 25, Issue 7 , 2016 ; 02181266 (ISSN) ; Frashidi, E ; Sadughi, S ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
Abstract
A Digital Delta Sigma Modulator (DDSM) is a Finite State Machine (FSM); it is implemented using finite precision arithmetic units and the number of available states is finite. The DDSM always produces a periodic output signal when the input is constant. This paper proposes a novel method of applying periodic dither to a DDSM in order to obtain minimized spurious tones. The effects of adding the pseudorandom dither signal in different stages within the proposed Multi-Stage noise Shaping (MASH) modulator are expressed in the equations, and the results are compared. We present results regarding the periodicity of the quantization noise produced by a MASH modulator with a constant input and a...
Probabilistic smart contracts: Secure randomness on the blockchain
, Article 1st IEEE International Conference on Blockchain and Cryptocurrency, ICBC 2019, 14 May 2019 through 17 May 2019 ; 2019 , Pages 403-412 ; 9781728113289 (ISBN) ; Kafshdar Goharshady, A ; Pourdamghani, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In today's programmable blockchains, smart contracts are limited to being deterministic and non-probabilistic. This lack of randomness is a consequential limitation, given that a wide variety of real-world financial contracts, such as casino games and lotteries, depend entirely on randomness. As a result, several ad-hoc random number generation approaches have been developed to be used in smart contracts. These include ideas such as using an oracle or relying on the block hash. However, these approaches are manipulatable, i.e. Their output can be tampered with by parties who might not be neutral, such as the owner of the oracle or the miners.We propose a novel game-theoretic approach for...
An adaptive secure channel coding scheme for data transmission over LEO satellite channels
, Article Scientia Iranica ; Volume 13, Issue 4 , 2006 , Pages 373-378 ; 10263098 (ISSN) ; Ahmadian, M ; Aref, M. R ; Sharif University of Technology
Sharif University of Technology
2006
Abstract
Both secure and error control coding are very extensive subjects, each with a variety of subdisciplines. A secure channel coding (joint encryption-channel coding) scheme provides both data secrecy and data reliability in one process to combat problems in an insecure and unreliable channel. In this paper, a joint encryption-channel coding scheme is developed, based on concatenated turbo codes for more efficient and secure transmission of LEO satellite data. Reliability and security are achieved by adapting the pseudo-random puncturing strategy with a change of distance between satellites and ground stations in the communication séance, an issue further burdened by reducing energy consumption...
Efficient and concurrent reliable realization of the secure cryptographic SHA-3 algorithm
, Article IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems ; Vol. 33, issue. 7 , July , 2014 , p. 1105-1109 ; 0278-0070 ; Mozaffari-Kermani, M ; Reyhani-Masoleh, A ; Sharif University of Technology
Abstract
The secure hash algorithm (SHA)-3 has been selected in 2012 and will be used to provide security to any application which requires hashing, pseudo-random number generation, and integrity checking. This algorithm has been selected based on various benchmarks such as security, performance, and complexity. In this paper, in order to provide reliable architectures for this algorithm, an efficient concurrent error detection scheme for the selected SHA-3 algorithm, i.e., Keccak, is proposed. To the best of our knowledge, effective countermeasures for potential reliability issues in the hardware implementations of this algorithm have not been presented to date. In proposing the error detection...
A robust spread spectrum watermarking method using two levels DCT
, Article International Journal of Electronic Security and Digital Forensics ; Volume 2, Issue 3 , 2009 , Pages 280-305 ; 1751911X (ISSN) ; Jamzad, M ; Sharif University of Technology
2009
Abstract
In this paper, a DCT-based blind watermarking scheme based on spread spectrum communications is proposed. We perform block-based DCT on the host image; then using the DC coefficients of each block, we construct a low-resolution approximation image. We apply block-based DCT on this approximation image, then watermark is embedded by adding a pseudo random noise sequence into its high frequencies. In detection stage, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method, higher robustness is obtained because of embedding...
On the performance of spectrally-encoded spread-time ultrawideband CDMA communication systems
, Article IEEE Transactions on Wireless Communications ; Volume 7, Issue 11 , 2008 , Pages 4608-4616 ; 15361276 (ISSN) ; Salehi, J. A ; Sharif University of Technology
2008
Abstract
In this paper we study the performance of Spectrally-Encoded Spread-Time (SE/ST) technique when applied to ultrawideband (UWB) signals in the context of wireless code-division multiple-access (CDMA) communication. In this technique UWB pulses are spectrally encoded with pseudorandom codes that are assigned uniquely to each user. We shall show that the SE/ST ultrawideband system provides an appropriate multi-user capacity in realistic UWB channels, along with the ability of narrowband interference (NBI) suppression. To this end, after obtaining a suitable statistical model for spectrallyencoded spread-time signals, we investigate the performance of the system in the presence of...
A power-efficient clock and data recovery circuit in 0.18 μm CMOS technology for multi-channel short-haul optical data communication
, Article IEEE Journal of Solid-State Circuits ; Volume 42, Issue 10 , 2007 , Pages 2235-2244 ; 00189200 (ISSN) ; Muller, P ; Leblebici, Y ; Sharif University of Technology
2007
Abstract
This paper studies the specifications of gated-oscillator-based clock and data recovery circuits (GO CDRs) designed for short haul optical data communication systems. Jitter tolerance (JTOL) and frequency tolerance (FTOL) are analyzed and modeled as two main design parameters for the proposed topology to explore the main tradeoffs in design of low-power GO CDRs. Based on this approach, a top-down design methodology is presented to implement a low-power CDR unit while the JTOL and FTOL requirements of the system are simultaneously satisfied. Using standard digital 0.18 μm CMOS technology, an 8-channel CDR system has been realized consuming 4.2 mW/Gb/s/channel and occupying a silicon area of...
Particles Size Distribution effect on 3D packing of nanoparticles into a bounded region
, Article International Journal of Engineering, Transactions A: Basics ; Volume 20, Issue 3 , 2007 , Pages 281-291 ; 17281431 (ISSN) ; Salehpoor, P ; Esmaielzadeh Kandjani, A ; Vaezi, M. R ; Sadrnezhaad, S. K ; Sharif University of Technology
Materials and Energy Research Center
2007
Abstract
In this paper, the effects of two different Particle Size Distributions (PSD) on packing behavior of ideal rigid spherical nanoparticles using a novel packing model based on parallel algorithms have been reported. A mersenne twister algorithm was used to generate pseudorandom numbers for the particles initial coordinates. Also, for this purpose a nanosized tetragonal confined container with a square floor (300 * 300 nm) were used in this work. The Andreasen and the Lognormal PSDs were chosen to investigate the packing behavior in a 3D bounded region. The effects of particle numbers on packing behavior of these two PSDs have been investigated. Also the reproducibility and the distribution of...
An ultra-broadband direct demodulator for microwave FM receivers
, Article IEEE Transactions on Microwave Theory and Techniques ; Volume 59, Issue 8 , August , 2011 , Pages 2131-2139 ; 00189480 (ISSN) ; Banai, A ; Sharif University of Technology
2011
Abstract
A new broadband frequency discriminator is introduced for demodulating the frequency modulated signals in the microwave frequency range. Direct demodulation with no need for tuning the center frequency of the resonance circuits is the most important advantage of the proposed technique. This technique uses the in-phase/quadrature demodulation, in some manner, without using any additional local oscillator for down conversion. Simulation of the proposed demodulator has been done with Advanced Design System software to evaluate and predict the system behavior. A setup based on the proposed method was designed and implemented in order to verify the accuracy of the theory. We tested the proposed...
A new spread spectrum watermarking method using two levels DCT
, Article International Journal of Electronic Security and Digital Forensics ; Volume 3, Issue 1 , 2010 , Pages 1-26 ; 1751911X (ISSN) ; Jamzad, M ; Sharif University of Technology
2010
Abstract
In this paper, a discrete cosine transform (DCT) based blind watermarking scheme based on spread spectrum communications is proposed. We perform block-based DCT (BDCT) on the host image; then using the DC coefficients of each block, we construct a low-resolution approximation image. We apply BDCT on this approximation image, then watermark is embedded by adding a pseudo random noise sequence into its high frequencies. In detection stage, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method, higher robustness is obtained...
A robust image watermarking using two level DCT and wavelet packets denoising
, Article International Conference on Availability, Reliability and Security, ARES 2009, Fukuoka, Fukuoka Prefecture, 16 March 2009 through 19 March 2009 ; 2009 , Pages 150-157 ; 9780769535647 (ISBN) ; Jamzad, M ; Sharif University of Technology
2009
Abstract
In this paper we present a blind low frequency watermarking scheme on gray level images, which is based on DCT transform and spread spectrum communications technique. We compute the DCT of non overlapping 8x8 blocks of the host image, then using the DC coefficients of each block we construct a low-resolution approximation image. We apply block based DCT on this approximation image, then a pseudo random noise sequence is added into its high frequencies. For detection, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method,...
Multiple-access performance analysis of combined time-hopping and spread-time CDMA system in the presence of narrowband interference
, Article IEEE Transactions on Vehicular Technology ; Volume 58, Issue 3 , 2009 , Pages 1315-1328 ; 00189545 (ISSN) ; Nasiri Kenari, M ; Sharif University of Technology
2009
Abstract
We consider a combined time-hopping (TH) and spread-time (ST) multiple-access technique that uses an internal code. In this method, the duration of each bit is divided into Ns frames. The outputs of the encoder and a pseudorandom (PN) sequence specify the number of the frame in which the data bit is transmitted in ST code-division multiple-access (ST-CDMA) form using the second PN sequence. We consider the correlator receiver, followed by the channel decoder. We obtain the performance of the combined method in additive white Gaussian noise (AWGN) and fading channels in the presence of multiple-access interference (MAI) and narrowband interference (NBI). We also consider the conventional...
Optimum code structures for positive optical CDMA using normalized divergence maximization criterion
, Article IEEE Transactions on Communications ; Volume 56, Issue 9 , 2008 , Pages 1414-1421 ; 00906778 (ISSN) ; Salehi, J. A ; Sharif University of Technology
2008
Abstract
In this letter we consider optimum code structure for positive optical code division multiple-access (optical CDMA) systems. Positive systems are a class of systems that operate with positive real numbers only. We consider the effect of multipleaccess interference in our model and show that code design for both On-Off Keying (OOK) and Binary PPM optical CDMA systems results in the same solutions. Furthermore, we show that a class of codes known as optical orthogonal codes (OOCs) are the best possible positive codes. In obtaining the results we define normalized divergence based on signal-to-multipleaccess interference ratio (SIR) for a multiple-access system in a useful manner and use it as...
A secure channel coding scheme for efficient transmission of remote sensing data over the LEO satellite channels
, Article 3rd International Conference on Recent Advances in Space Technologies, RAST 2007, Istanbul, 14 June 2007 through 16 June 2007 ; August , 2007 , Pages 510-514 ; 1424410576 (ISBN); 9781424410576 (ISBN) ; Ahmadian, M ; Aref, M. R ; Sharif University of Technology
2007
Abstract
Both secure and error control coding are very extensive subjects, each with a variety of sub-disciplines. In this paper, we develop a secure channel coding (joint encryption-channel coding) scheme based on concatenated turbo codes for more efficient and secure transmission of the LEO satellite data. Reliability and security are achieved by adapting the pseudorandom puncturing strategy with the change of distance between satellite and ground station in the communication séance, to issue further burdened by reducing energy consumption or increasing bit rate of data transmission. Simulation results show the relevance and superior performance of the proposed scheme compared with the traditional...