Unequal Power Allocation of Image Transmission in OFDM Systems

Abstract

The OFDM technique with cyclic time guard, which has been proposed for broadband communications, is an increasing approach to combat the frequency selectivity of the channel. In this paper, a modified OFDM scheme for image transmission is proposed. The new proposal is based on modification of the OFDM structure through using unequal power allocation for the successive OFDM symbols. Unequal cyclic time guard is also applied with unequal power allocation. The proposed method is compared with the conventional OFDM. Results show that the performance is improved at lower average cyclic extension periods and a lower average power when using the proposed method. The performance study of OFDM scheme is examined with and without forward error correction (FEC).