Serial Maximum a Posteriori Detection of Two-Dimensional Generalized Partial Response Target for Holographic Data Storage Systems

Round 1

Reviewer 1 Report

The authors report maximum a posteriori algorithm aimed at data detection in holographic data storage. The authors described the importance and the novelty of the study. The proposed model was compared with the methods of Serial detection with Viterbi and the model reported by Nabavi and Kumar. The authors analyzed bit rate error performance against SNR of initial signal and blur with and without misalignment. I believe that the manuscript is well written and can be published in Applied sciences after minor corrections, mentioned below. However I would recommend to describe the methods in more details when publishing in journals with such wide scope as Applied sciences.

- I believe that some terms utilized in the manuscript should be better described, for example, what is: intertrack-interference, isolated patterns, digital magnetic recording, generalized partial response, AGWN etc. Since the Applied sciences journal contains manuscripts from very different fields of science, I would recommend to better describe these terms and use less abbreviations. While mathematical description of the proposed detection model is well discussed, could you please also briefly describe practical (physical) realization of holographic data storage and reading.

- Why SNR variation takes place in exactly [10 16] range? Is this range typical for detection in holographic data storage systems?

- Could you also compare the operating rate of by your model and other methods, which you mentioned in fig. 4. I think it is another quite important parameter besides bit errors performance, which you analyzed.

- As far as I know, in some practical realizations of holographic data storage somewhat diffusion of the generated refractive index pattern may be observed over time. This is particularly the case when photopolymers are used for data storage. In this case refractive index of arbitrary spot is influences by surrounding area. Can you comment on how such diffusion may impact your approach of data detection?

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

In this paper, the authors propose a new detection algorithm based on the maximum a posteriori (MAP) algorithm to improve the BER performance of HDS systems. The proposed model inherits the structure of serial generalized partial response targets and designs a serial structure for MAP detection. With a well-organized introduction, a well-structured body, and conclusions based on simulated data, this paper provides new insights into the field. The reviewers believe that the paper is acceptable for publication as is, but would be improved with the following corrections

 

1. In page 6, “AGWN” should be “AWGN”.

2. Why is there no data from SNR=16 to 20 in the proposed method in Fig. 4?  The same applies to Blur=1.8 in Figs. 6 and 7.

3. Please comment on why the proposed model performs well in a misaligned environment.

Author Response

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Author Response File: Author Response.docx