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Digital Chaotic Scrambling of Voice Based on Duffing Map
Amina Mahdi,
Ameer K. Jawad,
Saad S. Hreshee
Issue:
Volume 1, Issue 2, October 2016
Pages:
16-21
Received:
15 June 2016
Accepted:
18 June 2016
Published:
26 August 2016
Abstract: With the significant development in communication systems especially in the public channels through which our information travels, there are more increasing in the channels problems. The information security is the important one that should be enhanced. This paper presents a chaos-based speech scrambling system. Chaotic maps have been successfully used for large-scale data encryption such as image, audio and video data, due to their good properties such as pseudo-randomness, sensitivity to changes in initial conditions and system parameters and a periodicity. In this paper a security model based on chaotic system has been designed to be used to encrypt voice signal, chaotic duffing map used for digital Scrambling, each samples of the speech are divided into 8 bits. The simulation results show that the Cpestral Distance Measure (CD) in the proposed system is increased by (4.559) by comparing with the time domain scrambling which is about four times that gives from the analog scrambling. In addition, dlpc increased to (4.428) as comparing with time domain. The key space in this proposed is 11.8336*1064×range of parameters.
Abstract: With the significant development in communication systems especially in the public channels through which our information travels, there are more increasing in the channels problems. The information security is the important one that should be enhanced. This paper presents a chaos-based speech scrambling system. Chaotic maps have been successfully ...
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Decision Wave Equation and Block Diagram of Electro Magneto Elastic Actuator Nano - and Micro Displacement for Communications Systems
Issue:
Volume 1, Issue 2, October 2016
Pages:
22-29
Received:
2 August 2016
Accepted:
12 August 2016
Published:
6 September 2016
Abstract: Decision wave equation, structural - parametric model and block diagram of electro magneto elastic actuators are obtained, its transfer functions are bult. Effects of geometric and physical parameters of electro magneto elastic actuators and external load on its dynamic characteristics are determined. For calculation of communications systems with piezoactuators the block diagram and the transfer functions of piezoactuators are obtained.
Abstract: Decision wave equation, structural - parametric model and block diagram of electro magneto elastic actuators are obtained, its transfer functions are bult. Effects of geometric and physical parameters of electro magneto elastic actuators and external load on its dynamic characteristics are determined. For calculation of communications systems with ...
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Spectrally Efficient SAC-OCDMA System Using a New Two-Code Keying Scheme
Hamza M. R. Al-Khafaji,
Razali Ngah,
Alaa J. Mousa,
S. A. Aljunid
Issue:
Volume 1, Issue 2, October 2016
Pages:
30-34
Received:
2 July 2016
Accepted:
19 August 2016
Published:
26 September 2016
Abstract: This paper introduces a new two-code keying scheme for increasing the spectral efficiency (SE) of spectral-amplitude-coding optical code-division multiple-access (SAC-OCDMA) system. The analytical expression is derived for the SE of SAC-OCDMA system based on the proposed scheme utilizing multi-diagonal (MD) code. The theoretical results demonstrate that the suggested scheme has an improved SE performance over the conventional unipolar encoding with direct detection technique. This SE enhancement is verified in simulation experiments.
Abstract: This paper introduces a new two-code keying scheme for increasing the spectral efficiency (SE) of spectral-amplitude-coding optical code-division multiple-access (SAC-OCDMA) system. The analytical expression is derived for the SE of SAC-OCDMA system based on the proposed scheme utilizing multi-diagonal (MD) code. The theoretical results demonstrate...
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Efficiency Improvement for Optical OFDM Systems
Mohammad Ghanbarisabagh,
Nasreddine Maloulki,
Bechir Nsiri
Issue:
Volume 1, Issue 2, October 2016
Pages:
35-38
Received:
27 July 2016
Accepted:
25 August 2016
Published:
30 September 2016
Abstract: The evaluation of Optical Orthogonal Frequency Division Multiplexing (OOFDM) using Least Mean Square Time-domain Equalizer (LMSTE), Recursive Least Squares-Time-domain Equalizer (RLSTE) and Decision Feedback Time-domain Equalizer (DFTE) to reduce Cyclic Prefix (CP) length over 1200 Km of Standard Single Mode Fiber (SSMF) is presented. All of these TEQs are used immediately after the fiber channel. They can cancel the residual Inter Symbol Interference (ISI) and Inter Carrier Interference (ICI) caused by both the Group Velocity Dispersion (GVD) and the CP length being shorter than the Channel Impulse Response (CIR). Using these TEQs allow the reduction in size of CP, and consequently leading to system performance improvement. DFTE can decrease the noise whereas RLSTE can achieve a higher convergence and better performance compared to LMSTE.
Abstract: The evaluation of Optical Orthogonal Frequency Division Multiplexing (OOFDM) using Least Mean Square Time-domain Equalizer (LMSTE), Recursive Least Squares-Time-domain Equalizer (RLSTE) and Decision Feedback Time-domain Equalizer (DFTE) to reduce Cyclic Prefix (CP) length over 1200 Km of Standard Single Mode Fiber (SSMF) is presented. All of these ...
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