Encrypted Image Transmission over OFDM System

Wireless communication refers to transfer of data and information without using a wire, cable or any electrical conductor. It is one of the most relevant technologies in mobile and computer communication today, primarily making use of radio waves. With emergence of this technology, security of the data transmitted became a pertinent issue. To prevent unauthorised access to valuable information, various security standards have been developed over the past few years. These improvements include methods such as encryption of data at source and decryption at destination, scrambling of data, precoding etc. In this paper, a dual sided encryption and scrambling technique for an OFDM system is proposed. An XOR algorithm is employed for encryption and chaotic scrambling is used to fulfil scrambling needs. The method is employed for a channel which is characterised by AWGN. 16-QAM is utilised to modulate the encrypted data. The BER for various images is tabulated. Clipping used in the proposed method helps improve PAPR of the given information.