Camera communication deblurring: A semiblind spatial fractionally-spaced adaptive equalizer with flexible filter support design

Abstract

In Optical Camera Communication systems an important issue is the spatial intersymbol interference (blurred images) that can arise when Multi-Input Multi-Output techniques are applied. However, the transmitted symbols are described with very high resolution, due to the high number of pixels composing the camera. To take advantage of this characteristic, in this paper we use a semiblind spatial fractionally-spaced adaptive equalizer to counteract the blur introduced by the optical channel. We formulate the adaptive algorithm in a way that permits to design the support of the Finite Impulse Response filter with flexibility. The choice of the support is related to the spatial shape of the blur encountered, by following an heuristic approach. The equalizer performances in terms of Bit Error Rate are presented in the numerical results showing performance improvement. We also show the behaviour of the equalizer when different filter supports are used.