Kramers–Kronig Transmission with a Crosstalk-Dependent Step Multiple-Input Multiple-Output Volterra Equalizer in a Seven-Core Fiber
, Tianze Wu 1, Chao Yu 2, Chuxuan Wang 3, Mohai Yue 1, Ran Gao 2, Qi Zhang 1, Zhipei Li 2, Qinghua Tian 1, Fu Wang 1 and Xiangjun Xin 1,2Round 1
Reviewer 1 Report
The authors experimentally demonstrate 260.4 Gbit/s 16QAM signal transmitting in a seven-core fiber with a KK receiver. The XT-MIMO-Volterra is proposed to reduce inter-core crosstalk and nonlinear degradation. The idea is interesting and the detection scheme is quite simple. The paper is well-written. The results seem solid. I recommend accepting it for publication after minor revisions. My detailed questions/suggestions are listed as follows.
1. In figure 3, why the performance of the KK receiver will decrease when the signal power increases to more than 0 dBm?
2. In figure 10, XT-MIMO-volterra performs slightly better than MIMO-volterra. What is the difference in complexity between XT-MIMO-volterra and MIMO-volterra?
3. In figure 5, why the minimum BER of different cores varies greatly?
Author Response
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Reviewer 2 Report
In this manuscript, the authors have experimentally demonstrated a net bit rate of 260.4 Gbit/s in a seven-core transmission system with a KK receiver. They analyzed the carrier-to-signal power ratio, signal power, frequency spacing and optical power. A multiple-input-multiple-output (MIMO) Volterra equalization algorithm is proposed to compensate for inter-core crosstalk and impairments induced by devices. The experiment shows that the algorithm obtains a gain of 0.7 dB. This paper covers an interesting topic and is well-written. However, it would benefit from additional details to make it more solid. My comments are as follows:
1. In the experimental setup, why did the RX1 and RX2 reception schemes are used?
2. Please evaluate the crosstalk level of 2.5 km MCF in the manuscript.
3. We know that inter-core crosstalk is essentially a linear impairment and therefore does not require nonlinear equalization techniques to compensate for it. Can the authors provide specific sources of nonlinearity and their performance?
Author Response
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Reviewer 3 Report
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Comments for author File: Comments.pdf
Nothing to comment.
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Round 2
Reviewer 3 Report
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Comments for author File: Comments.pdf
No comment on the quality of English.
Author Response
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Round 3
Reviewer 3 Report
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None
Author Response
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