A Systematic Review on Cognitive Radio in Low Power Wide Area Network for Industrial IoT Applications

Round 1

Reviewer 1 Report

Dear Authors,

The paper tries to provide a systematic review on Cognitive Radio in LPWAN for IIoT applications. Although the objective of paper is useful for academic scholars, but the quality of research is quite low. However, it can be improved significantly by an intensive and substantial revision. The followings are recommends and suggestions for revision:

1. The abstract section is quite long. Large portion of paragraphs can be moved to the Introduction.
2. There are actually two or three Research Questions (RQ)? The authors used RQ1, RQ2 and RQ2?
3. The paper should include Contribution part (can be emerged in Introduction section) to highlight the key findings from this research.
4. The structure of paper should be sketched out like a mindmap, which specifies the logic flow of sections to improve the readability. 
5. A table of abbreviations, nomenclatures is needed.
6. A table is required to summarized the key IIoT applications for each kind of CR LWPAN technologies for Comparative analysis.
7. Since the authors presents the RQ, they must be answered and analyzed by authors' perspectives to improve the integrity of research.
8. All the figures need to improve the quality. Specially, Figure 2 must be re-designed as a flowchart to improve the readability.
9. An intensive proofreading is needed to check and correct grammar and typos.

Author Response

Reviewer 1:  The paper tries to provide a systematic review on Cognitive Radio in LPWAN for IIoT applications. Although the objective of paper is useful for academic scholars, but the quality of research is quite low. However, it can be improved significantly by an intensive and substantial revision. The followings are recommends and suggestions for revision:

1. Concern 1: The abstract section is quite long. Large portion of paragraphs can be moved to the Introduction.

 Author Response: We have improved the abstract based on your suggestion. The modified abstract is as below:

“The Internet of things (IoT) helps several applications that require power control and low cost to achieve long life. The progress of IoT communications, mainly based on cognitive radio (CR) has been guided to the robust network connectivity ability. The low power communication is achieved for various IoT sensors applying the Low Power Wide Area Network (LPWAN) with the various technologies such as Sigfox, NB-IoT, and LoRaWAN. This paper aims to review the various technologies and protocols for industrial IoT applications. A depth of assessment has been achieved by comparing various technologies considering the key terms such as frequency, data rate, power, coverage, mobility, costing and QoS. This paper provides an assessment of sixty-four articles published on electricity control problems of IoT between 2007 and 2020. That prepares a qualitative technique of answering the research questions (RQ): RQ1: “What are the major power control issues regarding for IoT environment”?, RQ2: “How cognitive radio engage with the industrial IoT?”, and RQ3: “What key success factors need to comply for reliable IoT support in the industry?”. With the systematic literature assessment approach, the effects display on the cognitive radio in LPWAN can significantly revolute the commercial IoT. Thus, researchers are more focused in this regard. The study suggests that to conquer the critical research gaps, LPWAN cognitive enabled IoT, the essential factors of design need to be considered in the design mechanism of the cognitive LPWAN based IoT. A cognitive low energy architecture is brought to make sure efficient and stable communications in a heterogeneous IoT.  It will protect the network layer from offering the customers an efficient platform to rent AI, and various LPWA technology was explored and investigated.”

2. Concern 2: There are two or three Research Questions (RQ)? The authors used RQ1, RQ2 and RQ2?

 Author Response: We corrected the typo mistakes, The research questions are: RQ1, RQ2, and RQ3.

3. Concern 3: The paper should include Contribution part (can be emerged in Introduction section) to highlight the key findings from this research.

 Author Response: We modified the manuscript by including the contribution part at the end of the introduction section, e.g.

“The main contribution of this paper is a systematic literature assessment on a long variety of extensive location (Lora), sigfox era, long time evolution class m (LTE-m), and narrowband internet of things (NB-IoT) in low electricity extensive location LPWAN technology with an unlicensed spectrum. Cognitive LPWAN allows industrial IoT applications for smart city services to access different wireless and selects appropriate communication technologies to achieve the best interaction experience.”

4. Concern 4: The structure of paper should be sketched out like a mindmap, which specifies the logic flow of sections to improve the readability.

 Author Response: We have improved the manuscript by including the suggested paragraph, e.g.

“The article is organized as consisting of three sections. Section 2 presents a comprehensive study on methods material and methods, where it discusses the data collection, searching, selecting the papers, and it covers a depth review on cognitive enables industrial IoT applications, methods with each of their pros and cons. Section 2 also answered each of the research questions and highlighted the significance of the deployment,  the determinant factors for designing and modeling cognitive-enabled industrial IoT frameworks. Section 3 presents the concluding remarks with the future scope for this work is suggested.”

5. Concern 5: A table of abbreviations, nomenclatures is needed.

 Author Response: We included the nomenclature before the introduction section.

AI         Artificial Intelligence

BLE     Bluetooth Low Energy

CR       Cognitive Radio

CRLPWAN     Cognitive Radio Low Power Wide Area Network

CSMA Carrier Sense Multiple Access

CU       Cognitive User

FHSS  Frequency Hopping Spread Spectrum

eMTC  Enhanced Machine Type Communication

SCC    IEEE Standards Coordinating Committee

SDR    Software-defined radio

IoT       Internet of Things

IIoT      Industrial Internet of Things

ISM     Industrial, Scientific, and Medical

IWSNs Interference in Industrial Wireless Sensor Networks

LPWAN           Low Power Wide Area Network

NB-IoT             Narrow Band Internet of Things

MAC    Media Access Control

M2M    Machine-to-Machine

PU       Primary User

 LoRaWAN      Low Range Wide Area Network

QoS     Quality of Service

RQ      Research Question

SINR   Signal to Interference Noise Ratio

LTE     Long Term Evolution

LoRA   Bi-directional Long Short-term Memory

3GPP  Third Generation Partnership Project

5G       Fifth Generation

OFDMA          Othrogonal Frequency Division Multiple Access

WSN   Wireless Sensor Network

U-LTE Unlicensed LTE

VOs     Virtual objects

6. Concern 6: The A table is required to summarized the key IIoT applications for each kind of CR LWPAN technologies for Comparative analysis.

 Author Response: We have included the summarized table 2 and table 3.

7. Concern 7: Since the authors presents the RQ, they must be answered and analyzed by authors' perspectives to improve the integrity of research.

 Author Response:  RQ1, RQ2, and RQ3 has been answered in subsection 2.1 and 2.2

8. Concern 8: All the figures need to improve the quality. Specially, Figure 2 must be re-designed as a flowchart to improve the readability.

Author Response: We have improved the figure 2.

9. Concern 9: An intensive proofreading is needed to check and correct grammar and typos.

 Author Response:  The authors sincerely apologize for making such inconveniences. The grammatical, fragmentation, typographical, and other related errors have been revised through comprehensive proofread.

Reviewer 2 Report

The topic is interesting and a review would be very welcome, but:

You really need an extensive proof read.

I usually take notes on the pdf and then summarize it here, but since there is so much to change, I prefer to just attach the annotated pdf file

Please, I do not intend to discourage anyone, I do appreciate the effort put into the paper and the topic is relevant and of interest, but please, do an extensive proof reading and rewriting before consider it to be published.

Comments for author File: Comments.pdf

Author Response

The authors sincerely apologize for making such inconveniences. The grammatical, fragmentation, typographical, and other related errors have been revised through comprehensive proofread. As per reviewer suggestions, many sentences and paragraphs are rewritten to make the paper readable. Based on the reviewer's suggestion Figures 10 and 11 are deleted.

Round 2

Reviewer 1 Report

Thank you for the authors' effort for revision. The revise manuscript is improved, however, there exist several issues required to be corrected.

1. The research questions are not answered in a readable way. It is difficult to find the satisfied answers within the text. Please localize which specific parts, which specific sections answer which questions. For example, Section (a) provides a answer to the question R1 (R2, or R3) explicitly.
2. The manuscript tries to correct the grammar, typos, verb usage errors, but there exist a lot of errors. For example, line 456 [ Table 1 presents the summarized the key IIoT application..]. Line 399 [.. a PU network belong all to a cellular ..]. Line 402 [.. to an IoT network, that all devices on the Internet..].
3. Different font types were used in the text. For example, paragraph from line 134-139. 
4. PARTICULARLY, please dot not send reviewers the draft version of revised manuscript. 

Author Response

Concern 1: The research questions are not answered in a readable way. It is difficult to find the satisfied answers within the text. Please localize which specific parts, which specific sections answer which questions. For example, Section (a) provides a answer to the question R1 (R2, or R3) explicitly.

 Author Response: Authors would like to thank the reviewer for his/her great comment. We have improved the manuscript based on the suggestion. The research questions are clarified and discussed section-wise. For example, the RQ1 is answered and discussed in section 2.1, RQ2 in 2.2, and RQ3 in section 2.3.

Concern 2: The manuscript tries to correct the grammar, typos, verb usage errors, but there exist a lot of errors. For example, line 456 [ Table 1 presents the summarized key IIoT application..]. Line 399 [.. a PU network belong all to a cellular ..]. Line 402 [.. to an IoT network, that all devices on the Internet..].

 Author Response: We revised the manuscript extensively and corrected the typographical mistakes and grammatical issues.

Concern 3: Different font types were used in the text. For example, a paragraph from line 134-139. 

 Author Response: We modified the manuscript by including by following MDPI font.

Concern 4: PARTICULARLY, please do not send reviewers the draft version of revised manuscript. 

.Author Response:  Thank you for the suggestion, we supplied the revised manuscript and the changes are highlighted in red color.

Reviewer 2 Report

The document has improved a lot, but there are still a considerable amount of redaction errors.

It is really difficult to read the provided document due to changes marked in red. It is nice to have a change log, but I'd recommend it to be annexed to the document.

Table 1 should have the references on it

Table 2 is really confusing, the note makes

Figure 9 quality is really bad

Table 4 is barely readable

Typo on reference 11

What's between references 12 and 13?

The reference papers selection is really good, but the document is really hard to read and comprehend due to style issues and also, the lack of DOI references makes the research difficult.

Author Response

Comment 1:

It is really difficult to read the provided document due to changes marked in red. It is nice to have a change log, but I'd recommend it to be annexed to the document.

 Author Response:  

 Thank you for the great comment. We have supplied a revised manuscript where changes highlighted in red color.

Comment 2:  Table 1 should have the references on it

Author Response:  

We have supplied references for Table 1. For example :

“Table 1. Comparison Technologies of Low Power WAN [10, 13, 18, 20-28, 33-34]”

Author Response:  

Comment 3: Table 2 is really confusing, the note makes

Author Response:  We metioned the table note in the main text where Table 3 is cited and the table note is deleted from Table. For Example : “Table 3 presents Industrial IoT characteristics with different parameter requirements (L: Low; M: Medium; H: High)”

Comment 4: Figure 9 quality is really bad

Author Response:  We have supplied the improved Figure.

 Comment 5:

Table 4 is barely readable

Author Response:  We have revised Table 4 contents.

 Comment 6: Typo on reference 11

Author Response:  We revised the reference sequences based on the sequential citations. Therefore, the old 11 number reference is at 1 position now. And we have corrected the typo. For example: “

Muhammad Shafiq et al, "Handshake Sense Multiple Access Control for Cognitive Radio-Based IoT Networks", Sensors, 19(2), p.241, 2019”

Comment 7: What's between references 12 and 13?

Author Response:  Reference number 12 is not at 75, and we updated it with the appropriate style. For example: “Sinha RS, Wei Y, Hwang SH., "A Survey on LPWA technology: LoRa and NBIoT", Information and communication Technology Express, 2017”.  Ref. 13 is deleted.

Comment 8: The reference papers selection is really good, but the document is really hard to read and comprehend due to style issues and also, the lack of DOI references makes the research difficult.

Author Response:  Thank you for your nice comment. We have improved the manuscript thoroughly with style, English, and reference sequence numbers and cited properly.

Round 3

Reviewer 1 Report

Thank you for the authors' efforts for revision. The revised manuscript was improved considerably. However, it is not accepted in this current form until revision is made for correcting following issues:

• What is different between the font type in paragraph between line 11 to 116 with the other text in the manuscript? It seems like the authors use different font type and size. Please recheck.
• What is the blank table in line 280. Please recheck.
• Many typos and grammatical errors. For example, Line 291 [..PRN radiofrequency Specifically..]. Many of such errors within the text. 
• I suggest the authors should review intensively and carefully correct these kinds of issues before submitting.

Author Response

• Thank you for the authors' efforts for revision. The revised manuscript was improved considerably.

Author Response: Thank you.

• What is different between the font type in paragraph between line 11 to 116 with the other text in the manuscript? It seems like the authors use different font type and size. Please recheck.

Author Response: We have corrected the fonts by following the MDPI font style.

• What is the blank table in line 280. Please recheck.

Author Response: Thank you for the comment. I uploaded revised file and where no such empty table exists.

• Many typos and grammatical errors. For example, Line 291 [..PRN radiofrequency Specifically..]. Many of such errors within the text. 

Author Response:  We removed these issues and updated the manuscript

• I suggest the authors should review intensively and carefully correct these kinds of issues before submitting.

Author Response: Thank you. We have checked the manuscript carefully.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.