Wireless transmission of Karhunen-Loeve transformed images over A WGN

In this paper a new method is proposed for progressive image transmission over coded Orthogonal Frequency Division Multiplexing (OFDM) system with Low Density Parity Check Coding (LDPC) using Karhunen-Loeve(KL transform). Trigonometric transforms are used in this scheme for improving the performance of the OFDM systems and minimising the Peak to-Average Power Ratio (PAPR) of OFDM signal. The Additive White Gaussian Noise (AWGN) channel is chosen to improve the error resilience ability and transmission efficiency for progressive image transmission. The Set Partitioning In Hierarchical Trees (SPIHT) algorithm is used for source coding of the images to be transmitted. In the proposed scheme the transmit image data is KL transformed, then each component is transformed using either the Discrete Cosine Transform (DCT) or the Discrete Sine Transform (DST). The simulation results show that adding the DST to the KL transformed images improves the visual quality of reconstructed images and reduces the PAPR of OFDM signal more than the DCT to the KL transformed images.