OFDM-ML-IDM System for Efficient Wireless Image Transmission

Abstract

In this paper, orthogonal frequency division multiplexing multi-layer interleaved division multiplexing (OFDM-ML-IDM) system is proposed as an efficient image communication system. Regardless the image compression technique, in the proposed image communication system the digital image signal is represented with the digital data of non-compressed image format. Recently, coded IDM communications never got much attention as a promising image transmission technique. The main idea is to use both multi-layer coded IDM and chip-by-chip iterative detection concepts for both bandwidth efficiency and efficient detection, respectively. Different simulation parameters effect such as number of IDM layers, number of receiver iterations and non-linear power amplifier effects are studied. The system performance is also investigated in wireless Additive White Gaussian Noise (AWGN) and Rayleigh fading channels. The key performance indicators that are used for measuring the system performance are the visual quality metric in-terms of Peak Signal to Noise Ratio (PSNR) performance and the system reliability in-terms of bit error rate performance. The main contribution in this paper is to prove that: based on the application requirement and at definite SNR points; the multi-layer IDM reflects a slight performance change compared with the bandwidth consumption. Simulation results show that at low $$SNR = 6 \;{\text{dB}}$$ for single and double layers case study, the PSNR performance is $$51.1073 \;{\text{dB}}$$ and $$48.5636\; {\text{dB}}$$ respectively at wireless AWGN channel, but the double layer IDM achieves $$50\%$$ efficient bandwidth than single layer for exchange only $$2.5437\; {\text{dB}}$$ which is considered a minor PSNR performance compared with single layer IDM, as well as the quad layers PSNR performance is $$36.1849\; {\text{dB}}$$ with $$25\varvec{\% }$$ bandwidth consumption. For high $$SNR$$ , the performance has an excellent visual quality metric with efficient bandwidth consumption. Signal distortion technique such as clipping and companding methods are used to overcome the originated high peak to average power ratio based ML-IDM with large OFDM envelope fluctuations; hence we study the clip ratio and companding parameter effect on the visual quality metric performance.