2024-03-29T10:02:47Z
https://mjeer.journals.ekb.eg/?_action=export&rf=summon&issue=9500
Menoufia Journal of Electronic Engineering Research
1687-1189
1687-1189
2016
25
1
Performance Evaluation of Coded Cooperative Relay Based OFDM Wireless Communication System
Ahmed S
Mohamed
Mohammed
Abd-Elnaby
Sami A.
El-Dolil
This paper investigates the performance of a coded cooperative relay based Orthogonal Frequency Division Multiplexing (OFDM) wireless communication system using native rate 1/2 convolutional code and rate 1/3 turbo code. These investigations are focused on evaluating the performance of the proposed coded cooperative wireless communication system over both Additive white Gaussian Noise (AWGN) channel and different Stanford University Interim (SUI) channel models. The performance of the proposed coded cooperative relay based system is evaluated using MATLAB computer simulations and compared with direct transmission and other cooperative protocols i.e., Amplify-and-Forward (AAF) and Decode-andForward (DAF). The performance indicators used for comparison are Bit-Error Rate (BER) and spectral efficiency. The results show that the proposed coded cooperative system achieves lower Signal-to-Noise Ratio (SNR) values for the desired BER and achieves high spectral efficiency as compared to direct transmission, AAF and DAF based cooperative protocols. Finally, the results of computer simulations are included to demonstrate the efficiency of the proposed scheme.
2016
01
01
1
24
Menoufia Journal of Electronic Engineering Research
1687-1189
1687-1189
2016
25
1
Performance Study of Different Approaches Used in the Design of Hierarchical Routing Protocols fofo r Wireless Sensor Network
Amr M.
Kishk
Nagy W.
Messiha
Nawal A.
El-Fishawy
Abd-Elrahman A.
Alkaf
Ahmed H.
Madian
Routing protocols are used to route the sensed data of the sensor nodes in Wireless Sensor Network (WSN) to the network administrator. The choice of the routing protocol effects on the sensor nodes lifetime. This paper discusses different approaches used in the design of the routing protocols and their effectiveness on WSN performance. The routing protocols are classified according to the network structure or the operation of the routing protocol. One of the routing protocols according to the network structure is hierarchical routing protocol. The main aim of hierarchical routing protocols is to optimize energy consumption of sensor nodes by arranging the nodes into clusters. The energy is consumed in the process of sending and receiving data between the sensor nodes in WSN and also in the process of network clustering periodically. Different approaches are introduced through many hierarchical routing protocols. Their performance are compared with each other using popular metrics such as WSN lifetime and throughput. The results show that the dependence on Cluster Heads (CHs) lifetime to elect new CHs enhances the WSN lifetime in comparison with the periodic CH elections.
2016
01
01
25
52
Menoufia Journal of Electronic Engineering Research
1687-1189
1687-1189
2016
25
1
Two Efficient Unit Cell Designs for Polarization Independent 5-G Reflectarrays
Rania
Elsharkawy
A.R.
Sebak
Moataza
Hindy
Osama M.
Haraz
Adel A.
Saleeb
El-Sayed M.
El-Rabaie
h: 0px; "> This paper presents two different polarization independent unit cells for reflectarray antenna that are suitable for 5-G mobile base-station applications and compares between them. The first unit cell is composed of two concentric rings and a cross loop inside and the second one contains three circular rings for bandwidth enhancement. These reflectarrays are designed around 28 GHz with 10×10 aperture dimensions. The unit cells dimensions are 0.5×0.5. A pyramidal horn antenna is used for the feeding purpose. The F/D ratio is taken as one. All the simulation stages are carried on the CST microwave studio. The simulation results show that the design with the UC2 gives a better performance than the design with UC1 from the aperture efficiency and the side-lobe level perspectives. Both designs offer a good cross-polarization level.
2016
01
01
53
65
Menoufia Journal of Electronic Engineering Research
1687-1189
1687-1189
2016
25
1
A Survey of Different Steganography Techniques
E. A.
Elshazly
Safey A. S.
Abdelwahab
R. M.
Fikry
O.
Zahran
S. M.
Elaraby
M.
El-Kordy
Steganography is defined as the art and science of embedding datain a cover object without leaving a remarkable track on the coverobject, in other words it is the study of invisible communications. It isusually dealing with the methods of hiding the existence of data tobe transmitted in such a way that, it remains confidential. The mainobjectives of steganography are high capacity of the hidden data,perceptual transparency (invisibility), temper resistance,undetectability, computation complexity and robustness. It isclassified into three categories which are; pure (no key), secret key,public key steganography. According to the type of the cover object,there are different types of steganography which are; image, audio,video, network and text. In the image steganography, the secrecycan be achieved by hiding data into the cover image and generatingthe stego-image. According to the embedding techniques, there aredifferent techniques of steganography which are those embeddingin the spatial domain (substitution method), those embedding in thetransform domain (frequency domain), spread spectrum techniques,distortion techniques, masking and filtering techniques, and covergeneration techniques. Each of these techniques has its strengthsand weaknesses for different algorithms. This paper presents areview of these techniques; the different algorithms, concepts,advantages and disadvantages. The steps of the differentalgorithms of these techniques will presented in details, with acomparison between all these techniques. The different applicationsof steganography, the attacks, and the robust image steganographyagainst attacks are presented. Lastly, the future and the noveltrends in steganography are presented.
2016
01
01
66
102
Menoufia Journal of Electronic Engineering Research
1687-1189
1687-1189
2016
25
1
Maximum Power Techniques of Wind Energy System
Walaa
Mohammed
Galal
Atlam
This paper illuminates how to maximize the power extraction from wind energy system. This paper compare between two techniques for maximization the power. A method is presented based upon power signal feedback using fuzzy controller. The performance of the controllers design methodology is finally presented through a wind energy conversion system to maximize the extraction of power from wind energy (WE) system.
2016
01
01
103
118
Menoufia Journal of Electronic Engineering Research
1687-1189
1687-1189
2016
25
1
Maximum Power Point Tracker of PV using Fuzzy Controller
Walaa
Mohammed
Galal
Atlam
This paper introduces two techniques to control systems. We introduce two methods for achieving maximum power. Appropriate conditions for the stability of system are drawn depend on perturb & observer (P&O) and Mamdani fuzzy logic. We present which of these techniques can extract maximum power under high disturbance. The proposed controllers design methodology are finally proved through a photovoltaic to maximize the Photovoltaic (PV) system.
2016
01
01
119
133