Gamal Mabrouk Abdel–Hamid, Sahar Abdel-Rahman, Hala Farrag “Performance Improvement of MIMO-OFDM Wireless Systems using PAPR Reduction Techniques", International Journal of Computer Applications (IJCA), 2012. Gamal Mabrouk Abdel–Hamid, Sahar Abdel-Rahman and-Hala Gaber Farrag, "Performance Analysis of Peak–to –Average Power Ratio Reduction Techniques in MIMO-OFDM Wireless Systems ", journal of Azhar University Engineering Sector. Cairo, Egypt, 2011 Sahar A. El_Rahman, Mahmoud E. Allam, Hala A. Elqader, And Mazen Selim, ”Reconstruction Of High Resolution Image From A Set Of Blurred, Warped, Undersampled, And Noisy Measured Images”, © IEEE, ICENCO 2010, 6th International Computer Engineering Conference Sahar A. El_Rahman, Mahmoud E. Allam, and Hala A. Elqader, “Super-Resolution Approach with Affine Block-Based Model”, Engineering Research Magazine, Faculty of Engineering, Shoubra, Egypt, 2007. Sahar A. El_Rahman, Bashayer A. Al-Twaim, “Development of Quality Assurance System for Academic Programs and Courses Reports”, International Journal of Modern Education and Computer Science, IJMECS Vol.7, No. 6, June 2015, pp.30-36. Naglaa. F. Soliman, Samia. M. Abd -Alhalem, Sahar A. El_Rahman, Mohammed. M. Fouad, and Fathi E. Abd El-Samie, “Speech Enhancement Transmission with COFDM based on Different Discrete Transforms”, International Journal of Speech Technology (IJST), © Springer, 2016, DOI 10.1007/s10772-016-9348-2. Sahar A. El_Rahman, “A Health Cloud Framework to Present a Comprehensive EHR Integrated System”, Software Engineering Journal, Vol. 5, No. 1, Feb. 2017, pp. 1-7. doi: 10.11648/j.se.20170501.11 A Secure Cloud Based Digital Signature Application for IoT