Nagy W. Messiha

Chaotic encryption of speech signals in transform domains

A speech encryption system based on substitution and permutation is described. The stream of speech segments is divided and reshaped into two fixed size blocks and the elements are permutated by chaotic map technique, then substituted to different values by discrete cosine transform (DCT) and then permutated another time to eliminate attacks with known plaintext attack. Finally, chaotic speech signals that completely different from original signal is generated. The proposed low complexity system will avoid the delay resulting from the use of simple substitution and fast permutation process. the target of the proposed system is to change the characteristics of speech signal and eliminate the intelligibility of the encrypted signal‥ The security aspects of the proposed system will depend on different parameters including secret blocks size, permutation process and variable number of rounds.

Encryption of speech signal with multiple secret keys in time and transform domains

This paper introduces a new speech cryptosystem, which is based on permutation and masking of speech segments using multiple secret keys in both time and transform domains. The main key is generated, randomly, using a Pseudo Noise (PN) sequence generator, and two other keys are generated from the main key to be used in the subsequent rounds of encryption. Either the Discrete Cosine Transform (DCT) or the Discrete Sine Transform (DST) can be used in the proposed cryptosystem to remove the residual intelligibility resulting from permutation and masking in the time domain. In the proposed cryptosystem, the permutation process is performed with circular shifts calculated from the key bits. The utilized mask is also generated from the secret key by circular shifts. The proposed cryptosystem has a low complexity, small delay, and high degree of security. Simulation results prove that the proposed cryptosystem is robust to the presence of noise.

Chaotic encryption of speech signals

This paper introduces a speech encryption approach, which is based on permutation of speech segments using chaotic Baker map and substitution using masks in both time and transform domains. Two parameters are extracted from the main key used in the generation of mask. Either the Discrete Cosine Transform (DCT) or the Discrete Sine Transform (DST) can be used in the proposed cryptosystem to remove the residual intelligibility resulting from permutation and masking in time domain. Substitution with Masks is used in this cryptosystem to fill the silent periods within speech conversation and destroy format and pitch information. Permutation with chaotic Baker map is used in to maximize the benefits of the permutation process in encryption by using large-size blocks to allow more audio segments to be permutated. The proposed cryptosystem has a low complexity, small delay, and high degree of security. Simulation results prove that the proposed cryptosystem is robust to the presence of noise.

System Design and Performance Analysis of LTE Cognitive Femtocells

Femtocells’ deployment can extend the LTE coverage to include indoor areas. Unfortunately, a mutual electromagnetic interference can occur among the macro cells and femtocells due to the co-channel deployment. Moreover, interference among the femtocells themselves can occur due to utilizing the same subcarriers. The two types of interference can degrade the system performance. Femtocells base station power control can reduce the interference, which affects the macro users at the expense of a drop in the femto users’ geometry and throughput. A cognitive radio is proposed, as a novel approach, to completely eliminate the mutual interference among the macrocells and femtocells. The system is designed, mathematically analyzed, and simulated considering that the femto users are secondary users for the macro users. Analytical and simulation results show that applying the cognitive radio, to improve the system performance, is better than applying power control algorithms. The interference, which occurs among the femtocells, can be eliminated by different techniques. These novel techniques, which can achieve a maximization of the femto users’ geometry, are proposed and illustrated in details.

Hybrid Compression Algorithm for Wireless Sensor Network

Discrete Wavelet Transform (DWT) was developed to improve the performance of data compression. Hybrid Fast Zonal-DCT with DWT is proposed to enhance the image compression during the transmission in WSN. The reduction in power consumption relies on data distribution in the clusters. The performance of the proposed algorithm is monitored by some metrics. The enhancement in image quality and compression ratio is achieved.

Evaluation of Electromagnetic Interference in Wireless Broadband Systems

Nowadays, the electromagnetic compatibility in radio frequency communication systems attracts a great attention as the wireless spectrum becomes overcrowded. A lot of wireless systems operate in the same bands or in the adjacent frequency ones. This operation results in an electromagnetic interference (EMI) among these systems. This EMI can degrade the performance of the wireless systems. Moreover, critical medical equipment, which is near to an electromagnetic radiation field, may be malfunction. A lot of studies handled the EMI phenomenon in radio systems. These studies range from the definition and the causes of the phenomenon to the development of suitable simulation tools for evaluating the EMI value. This paper handles the effect of the EMI existence on the performance of a broadband communication system in a complex radio environment. Moreover, this performance is clarified in a form of bit error rate. In addition, the complex radio environment is modeled as a summation of noise, narrow band interference (NBI), and ultra wide band interference (UWBI). The complete analysis model of a broadband radio system, which is interfered by a NBI and an UWBI, is carried out. Furthermore, the total interfering power is derived in a novel closed form formula. Finally, the performance of the system is simulated.

Utilizing the Internet of Things (IoT) Technologies in the Implementation of Industry 4.0

The first Industrial Revolution took place in the \(17^{th}\) and \(18^{th}\) centuries. Since then, the evolution of the industrial revolution has continued. At present, Industry 4.0 a new industrial paradigm is already creating euphoria among technology professionals. The implementation of Industry 4.0 will significantly rely on Internet of Things (IoT) technology. IoT is poised to become the next big thing in the IT arena. However, the use of IoT technology to implement Industry 4.0 will require a collaborative efforts. There are many aspects that all stake holders both in IT world and Industry 4.0 will need to consider; these multiple aspects can be defined (i) smooth integration of the newly developed IoT sensors (things) into existing industries. (ii) Transparent secure communication channel and software layer to link manufacturing data with cloud based SW platforms. (iii) Developing a standard IoT architecture; Open standard is vital to guarantee hundreds of millions of Internet-connected things are inter-operable and being able to communicate with each other. (iv) Big Data storage and management capability. (v) Development of energy efficient IoT sensors and devices. The objective of this study is to explore the role IoT and related technologies such as cyber-physical systems (CPS) will play in the implementation of Industry 4.0. The paper begins with an introduction that gives an overview of IoT and Industry 4.0. The rest of the paper is divided as follows; integration between Industry 4.0 and IoT, Cyber physical system and industry 4.0, prerequisites of IoT technology, challenges and a conclusion.

C10. Haar Wavelet Image Compression Algorithm (HW-JPEG2000)

One of the popular image compression algorithms is Joint Photographic Experts Group 2000 (JPEG2000). It is based on Discrete Wavelet Transform (DWT). The enhancements in JPEG2000 guide us to Haar Wavelet Image Compression Algorithm (HW-JPEG2000) in this paper. HW-JPEG2000 enhances the use of DWT multi stages in JPEG2000. Although, the use of DWT multi stages in JPEG2000 reduces the image quality and increases the energy consumption in Wireless Sensor Network (WSN), it enhances the image quality and reduces the energy consumption in HW-JPEG2000. The traditional image compression algorithms with their popular enhancements are: JPEG, JPEG2000, 2D DWT-Zonal, Block Truncation Coding (BTC), and another enhancements for BTC. The comparison with the traditional algorithms is based on some important metrics in this area such as: Peak Signal to Noise Ratio and energy consumption. HW-JPEG2000 enhances the image quality and reduces the energy consumption in comparison with the distributed compression algorithms in WSN.

Channel Encryption in Wireless Camera Sensor Network

Data security is one of the greatest problems in Wireless Camera Sensor Network. Many encryption algorithms are used for encryption purposes. A new encryption algorithm is proposed in this paper. It depends on three secret parameters and four key-updating processes. It is compared with other encryption algorithm depending on key-updating beside Chaos encryption algorithm. Correlation Coefficient (CC), Spatial Frequency )SF(, processing time, and histogram are the metrics used for comparison purpose.

Cl. Subcarrier Gain basedPower Allocation in Multicarrier Systems

The Orthogonal Frequency Division MuItiplexing (OFDM) transnussIOn scheme is the optimum version of the muIticarrier transmission scheme which has the capability to achieve high data rate transmission. The key issue of OFDM system is the allocation of bit and power over number of subcarriers. In this paper, a new power allocation algorithm based on subcarrier gain is proposed to maximize the bit rate. For OFDM system, the subcarrier gain based power allocation (SGPA) algorithm is addressed and compared with the standard greedy power allocation (GPA). We demonstrate by analysis and simulation that the proposed algorithm greatly reduces the computational complexity and achieves near optimal performance in maximization the bit rate over number of subcarrier.