| Next-generation data storage requirements include the need for random-access, large-capacity, and small form factor media. Current trends suggest that magnetic and magneto-optical media will not be able to keep up with the demand. Volume digital holographic data storage shows promise as a solution to meet these data storage needs. However, digital holographic data storage suffers from unique optical channel effects that create difficulties with error-free data recovery.; The subject of this research is the improvement of the storage capacity of digital holographic systems. The holographic channel is analyzed in a communication-theoretical framework, facilitating the adaptation and design of methods similar to those employed in communication systems for the improvement of throughput and reliability. Methods detailed in this document include modulation coding and equalization. Equalization and channel detection are developed with consideration of efficient computational implementation, so that the algorithms might be realized in parallel computational elements. The coding methods described herein are developed for a high-perturbation channel, such as that which might result from optical element cost reduction for a competitively-priced commercial product.; Experimental and simulation results demonstrate the viability of these methods for coding and data recovery. Additionally, these methods are shown to perform better (either in bit error rate or in computational efficiency) than established methods in some high-perturbation channels. Possible directions for the extension of this work are given, including further experiments to be performed in the short-term, as well as long-term enhancements and exploration. |
