While LCD technology is improving on pixel to pixel isolation,some of the image capture distortions still remain, causing
neighboring pixels of the barcode mix up in the image and resulting in some kind of Inter Symbol Interference. Themain idea in resolving this problem is to interpret the barcode image as a wireless radio signal for which ISI reduction techniques have already been proven successful. One of the best and most feasible modulation methods capable of coping with severe conditions in band limited communication channels is the so-called Orthogonal Frequency Division Multiplexing or OFDM [22]. The general idea is that when dealing with band-limited, power-constrained,multipath channels, it is more efficient to transfer a bunch of narrow-band signals in parallel instead of a single high bandwidth signal.