Compressed image transmission over FFT-OFDM: A comparative study

In this work we present a comparative study for the transmission of a wavelet-compressed still image using FFT-OFDM over multipath channels with additive white Gaussian noise (AWGN). Rather than using a global threshold for the compression of the wavelet coefficients, we chose to compress the data by transmitting only the low-pass subbands from each decomposition level. 16-QAM is considered for the modulation of the data and various wavelets are considered. A comparison is also performed between the common discrete cosine transform (DCT) compression method and the DWT to compare accuracy and efficiency of data transmission using the two methods. The performance criteria for our compression methods include the compression ratio and relative root-mean-squared (RMS) error of the received data.