Decision-free downsampling method assisted via channel-transfer information to improve the reliability of holographic data storage systems.

A decision-free downsampling method (DFDS) assisted by channel-transfer information for phase-modulated holographic data storage is proposed. DFDS is used to address the issue of the accumulation of decision errors induced by traditional downsampling. The issue degrades the downsampling accuracy. DFDS comprises two functional segments: acquiring the channel-transfer information offline and performing decision-free downsampling online. With the assistance of the channel-transfer information, DFDS uses Bayesian posterior probabilities instead of traditional decision results to avoid the accumulation of decision errors and achieve more accurate downsampling. The simulation and experimental results show that DFDS reduces the phase error rate, thereby improving the reliability of the holographic data storage system.