2-D Non-Isolated Pixel 6/8 Modulation Code

Elimination of two‐dimensional intersymbol interference through the use of a 9/12 two‐dimensional modulation code

“…To overcome the challenge presented by 2D ISI, many solutions regarding the readback part have been suggested in previous reports including the following: (i) solutions based on 2D equalisation [5, 6], (ii) solutions based on 2D soft output Viterbi algorithm (SOVA) [7–9], and (iii) solutions based on the principle of turbo equalisation [10–12]. Alternatively, a user‐data encoding procedure is also used for the writing part in ultra‐high‐density storage systems [13–20]. Applying advanced encoding schemes such as the low‐density parity‐check code, one of the turbo codes, for these systems yields the significant improvements regarding the system performance [13–15].…”

“…A conservatively constrained, multimode 2D balanced code was introduced for holographic storage [17], whereas Groenland and Abelmann [18] introduced a 7/9 2D channel code where ‘one’ and ‘zero’ bits are fixed to avoid the 2D interference at every 3‐by‐3 data array. Further, a 6/8 modulation code with non‐isolated patterns was introduced in [19] for the mitigation of the 2D ISI problem, and an 8/9 modulation code [20] was recently investigated to eliminate the 2D interference in a BPMR system. In this study, we propose a 9/12 modulation code for the mitigation of not only 2D ISI patterns, but also the effect of ITI patterns.…”

“…The 2D array is designed in such a manner that the 2D ISI and ITI patterns do not exist in any part of the 2D output array, but a reasonable Hamming distance is still retained between the codewords. To assess the performance of the proposed modulation code, we compared the proposed scheme with the following three cases, (i) non‐encoding; (ii) the 6/8 2D modulation code [19] regarding the same code rate; and (iii) the 8/9 2D modulation code [20] that is the most recent 2D modulation code applied for BPMR systems. The simulation result shows that the proposed model offers a superior bit error rate (BER) performance compared with those of the other approaches.…”

Synchronous OEIC Integrating Receiver for Optically Reconfigurable Gate Arrays

“…To address this issue, holographic memories in conjunction with optically reconfigurable gate arrays (ORGAs) are proposed as a viable solution for applications demanding high reconfiguration speeds and gate densities [ 1 , 2 ]. The reconfiguration contexts are stored in the whole 3-D volume of the holographic memory in a page structure, thus achieving high density, and they are retrieved projecting the information stored in each page on an array of optical detectors, which allows operation at hundreds of megahertz [ 1 , 2 ].…”

8/10 two‐dimensional modulation code for holographic data storage systems

“…For instance, at the BER of 10 −6 , the proposed code provides a gain that is approximately 2.5 dB higher than that of the raw signal under the blur grade of 1.85; at the blur grade of 1.9, the proposed one boosts the system performance approximately 6 dB more than the raw signal. Recently, a 6/8 modulation code was suggested for HDS systems [4]. The code only contains the codewords that two adjacent bits are identical symbol at least.…”