TEXT FILE ENCRYPTION USING FFT TECHNIQUE IN LAB VIEW 8.6

Abstract

Encryption has always been a very important part of military communications. Here we deal with digital transmission technique. Digital transmission is always much more efficient than analog transmission, and it is much easier for digital encryption techniques to achieve a very high degree of security. Of course, this type of technique is still not quite compatible with today’s technical environment, i.e. most of the telephone systems are still analog instead of digital; most practical digitizers still require a relatively high bit rate which cannot be transmitted via standard analog telephone channels; and low bit rate speech digitizers still imply relatively high complexity and poor quality. Digital transmission adopts “Scrambling” technique. Scrambling methods are considered as important methods that provide the communication systems a specified degree of security, depending on the used technique to implement the scrambling method. There are many traditional scrambling methods used in single dimension such as time or frequency domain scrambling.