الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
 |  | from | 98 |  |  |
| | | from | 98 | | |
Abstract
This thesis studied several data encryption techniques including optical and digital encryption. It has introduced three cryptosystems that are able to increase the immunity to noise, reduce processing time and resist cryptanalysis attacks. One of these three cryptosystems depends on the double random phase encryption and Arnold cat map, while the other one depends on double random phase encryption and Henon map, and the third one depends on preprocessing encryption and quadruple phase modulation. A framework has been developed in this thesis to achieve multi-level security through authorized identification. Simulation results have shown great success of the authorized identification system performance, which means that these encryption techniques can be used to enhance the security of the authorized identification system.