Motion-Induced Noise Detection of Electrode-Pair Towed Antennas Using Helix Coil Sensors
Round 1
Reviewer 1 Report
Manuscript review No: electronics-2308509
Title: Motion-Induced Noise Detection of Electrode-Pair Towed Antennas Using Helix Coil Sensors
Authors: Xu Xie, Hao Zuo, Shize Wei and Qin Wu
A. Overview
1. In this manuscript the authors present a theoretical and experimental study on a method for detecting the motion-induced noise of electrode-pair towed antennas using helix coil sensors .
2. The contents are expressed clearly; the manuscript must be re-organized, and English could be improved. Reading of the manuscript is required as several misprints and grammar issues ca be found in the manuscript.
3. The authors have acknowledged recent research on this topic; however a few references are old (1974, 1989, …) – I advise using recent review articles instead.
4. As long as my knowledge, the work presented has a few keys of originality, however this is not a remarkably new subject.
B. Detailed analysis.
Abstract: Please organize the ideas in different paragraph:
Be clear, objective. State briefly what you did, how did you do it, the quantitative results you and state clearly the novelty of your work.
- ELF/SLF not defined
1. Introduction: provides an interesting approach to the subject and there are up to date references, however some are old (1974, 1989, …) – use recent review articles as I said before.
- Line 55 to 63 is Conclusions not Introduction
2. Proposed Methods: this section should be divided in two. One section with the relevant theory and Sensor structure and other with Material and Methods used in de work, including the equipment used ans suppliers.
- a detailed description of the methodology is given
- Figures captions must be self-explanatory
C. Overall assessment
The work presented here is very interesting and has potential for further developments. In my opinion it must be checked again before a decision can be made.
D. Review Criteria
1. Scope of Journal
Rating: Medium
2. Novelty and Impact
Rating: Low
3. Technical Content
Rating: Medium
4. Presentation Quality
Rating: Low
Author Response
Response to Reviewer 1 Comments
Point 1: The authors need to clearly highlight their main contribution and novelty of their proposed experimental design over the already reported in the literature.
Response 1: Relevant content has been added to the contributions in Section 1. “Accelerators are mainly used for motion-induced noise detection in previous lit-eratures, which include piezoelectric, piezoresistive, capacitive, and servo sensors [13], etc. However, the towed antenna is hundreds of meters long, and the acceler-ators can only detect local signals, which is easy to lose high frequency harmonics. In-stalling a large number of accelerators will lead to an increase in antenna cable density and affect the positive buoyancy. In addition, accelerators need long-distance power supply, and the harmonics will interfere with the weak ELF/SLF received signals. Thus, we propose a type of helix coil sensors. It is conformally installed along the antenna cable without power supply, which has shown a strong prospect for practical engi-neering.”
Point 2: The authors should explain the acronyms ELF/SLF and RLCG used in the abstract.
Response 2: Explanatory content for the abbreviations ELF/SLF and RLCG has been added to the abstract. “However, the motion-induced noise created by antenna vibrations due to environmental turbu-lence affects extremely low frequency and super low frequency (ELF/SLF) communications. In this article, we present a method for detecting the motion-induced noise of electrode-pair towed an-tennas using helix coil sensors. The equivalent resistance, inductance, capacitance and conduct-ance (RLCG) transmission model and parameters have been derived based on mirror method of the twisted structure with a shielding layer inside.”
Point 3: The helix sensor structure shown in Fig. 1, should be explained in a little bit more detail in section 2.1. For example, why the length of 1000 mm is chosen, and what is the function of the two electrodes, and the filter?
Response 3: A refined description of the spiral wire sensor structure has been added in section 2.1. “In contrast to magnetic antennas [14], the helix coil sensors comprise of a metal coil, a low-noise amplifier, and a filter with an air core, as illustrated in Figure 1. A typical configuration of 1000mm-long differentially twisted wire is coiled axially along the antenna with 80 turns. This transmission structure can be seen as a short circuit at the end and a low noise amplifier (LNA) at the beginning. Two electrodes are mounted at both ends of the antenna, respectively 20mm from the helix coil sensors, receiving ELF/SLF signals.”
Point 4: How the number of coil turns (N=80) in the helix coil sensor is optimized for the best performance?
Response 4: A description of the number of coil turns related to helix coil sensors has been added in section 2.2. “From equation (2), the motion induced voltage is proportional to turns of helix coils. However, turns per unit length cannot be infinite, where the upper limit depends on the density of the antenna cable. According to the actual engineering positive buoyancy requirements, the cable density is about 0.6-0.8. Therefore, it is necessary to optimize the turns of helix coil sensors according to the material, radius, wire diameter and other parameters.”
Point 5: The experimental results in section 3 are very brief and without details.
Response 5: Add the content related to the analysis of experimental results and description of details in section 3. ” The experimental section is depicted in Figure 4. In order to compare the perfor-mance of sensors and electrode-pair simultaneously, the sensors are installed confor-mal with the antenna cable using enameled copper wires. The near-end electrode and far-end electrode are mounted near both ends of the section.”
Point 6: The caption of Fig. 4 is hidden under the figure.
Response 6: The position of the caption of Figure 4 has been modified.
Figure 4. Experimental section of the towed antenna.
Point 7: How was data acquired during the water flow cycling experiment?
Response 7: The data acquisition interface for the water flow cycling experiments has been shown in Figure 4 and Figure 5 a related description has been added in Section 3.1. “The experiments are conducted in water-flow cycling experimental platform de-picted in Figure 5, which is filled with 4% salt water to replicate saltwater. The plat-form consists of a thick-walled aluminum pipe through which salt water can be con-tinuously flowed in and out. The experimental section is in shielded housing with an output port connecting to a LNA and a data acquisitor. The antenna's end is attached to a vibrator in order to imitate various accelerations.”
Figure 5. Experimental platform for water flow cycling.
Point 8: In Figure 9, there are two separate figures that should be labeled (a) and (b) for clarity of the reader.
Response 8: Captions have been labeled in (a) and (b) of Figure 9, and independent descriptions have been added. “(a) The PSD of electrode-pair” and “(b) The PSD of helix coil sensors”.
Point 9: A better-quality picture in Figure 10 could improve the understanding of the reader. The room light is affecting the picture quality as reflections are blurring the sensor.
Response 9: Updated Figure 10 to re-take clear photos to avoid fiber optic reflections affecting picture quality.
Figure 10. Improved experimental section of the towed antenna.
Point 10: There are a few typos in the manuscript that need to be fixed.
Response 10: The relevant typos have been corrected. Thanks for pointing out.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This paper reports a new method for detecting the motion-induced noise of electrode pair towed antenna using helix coil sensors. A water-flow cycling experimental platform is constructed to demonstrate the motion-induced noise detected by the proposed sensor. I have the following comments/concerns regarding the submitted manuscript that could potentially improve the overall quality and readability of the submitted manuscript.
1. The authors need to clearly highlight their main contribution and novelty of their proposed experimental design over the already reported in the literature.
2. The authors should explain the acronyms ELF/SLF and RLCG used in the abstract.
3. The helix sensor structure shown in Fig. 1, should be explained in a little bit more detail in section 2.1. For example, why the length of 1000 mm is chosen, and what is the function of the two electrodes, and the filter?
4. How the number of coil turns (N=80) in the helix coil sensor is optimized for the best performance?
5. The experimental results in section 3 are very brief and without details.
6. The caption of Fig. 4 is hidden under the figure.
7. How was data acquired during the water flow cycling experiment?
8. In Figure 9, there are two separate figures that should be labeled (a) and (b) for clarity of the reader.
9. A better-quality picture in Figure 10 could improve the understanding of the reader. The room light is affecting the picture quality as reflections are blurring the sensor.
10. There are a few typos in the manuscript that need to be fixed.
Author Response
Response to Reviewer 2 Comments
Point 1: 1. In this manuscript the authors present a theoretical and experimental study on a method for detecting the motion-induced noise of electrode-pair towed antennas using helix coil sensors . The contents are expressed clearly; the manuscript must be re-organized, and English could be improved. Reading of the manuscript is required as several misprints and grammar issues ca be found in the manuscript.
Response 1: Thanks for reviewing carefully and giving valuable advice. The relevant English writing errors have been corrected and modified.
Point 2: The authors have acknowledged recent research on this topic; however a few references are old (1974, 1989, …) – I advise using recent review articles instead.
Response 2: Some of the literature of recent years has been added, such as [14],[17]. The literature of 1974 written by M. Burrows is a classic study of the motion-induced noise, which is used for introduction as background in this article.
Point 3: As long as my knowledge, the work presented has a few keys of originality, however this is not a remarkably new subject.
Response 3: Motion-induced noise detection is a long-standing constraint on underwater ELF/SLF communication, limited by the difficulty of the experiment and special application areas. As the development of submarine speed, noise has become a key issue limiting the signal receiving. So, in nowadays, motion-induced noise has been received more and more attentioned, becoming more important. Many more scholars are carrying out related research in the ELF/SLF communication area.
Point 4: B. Detailed analysis. Abstract: Please organize the ideas in different paragraph:
Be clear, objective. State briefly what you did, how did you do it, the quantitative results you and state clearly the novelty of your work. ELF/SLF not defined
Response 4: Explanatory content for the abbreviations ELF/SLF and RLCG has been added to the abstract. “However, the motion-induced noise created by antenna vibrations due to environmental turbu-lence affects extremely low frequency and super low frequency (ELF/SLF) communications. In this article, we present a method for detecting the motion-induced noise of electrode-pair towed an-tennas using helix coil sensors. The equivalent resistance, inductance, capacitance and conduct-ance (RLCG) transmission model and parameters have been derived based on mirror method of the twisted structure with a shielding layer inside.”
Point 5: 1. Introduction: provides an interesting approach to the subject and there are up to date references, however some are old (1974, 1989, …)
– use recent review articles as I said before. Line 55 to 63 is Conclusions not Introduction
Response 5: Some of the literature of recent years has been added, such as [14],[17]. Lines 55-63 have been revised to read Introduction-related. “A new helix coil sensors structure with conformal towed antenna is proposed to simultaneously detect the motion-induced noise of electrode-pair towed antenna. The RLCG transmission line model is established. The influence of the inner shielding layer on the mutual inductance of the helix coil is analyzed based on the mirror principle, and the potential equation of the antenna is derived.
The water flow cycling experimental platform is constructed. Two type of towed antenna sections are designed and testified. Results showed that the helix coil sensors detect motion-induced noise synchronized with the electrode-pair, and achieve higher correlation with vibrations than accelerators.”
Point 6: Proposed Methods: this section should be divided in two. One section with the relevant theory and Sensor structure and other with Material and Methods used in de work, including the equipment used ans suppliers.
- a detailed description of the methodology is given
- Figures captions must be self-explanatory.
Response 6: Proposed methods section has divided in two parts: 2.1. Sensor structure, 2.2. Principle of motion-induced noise detection and 2.3. Equivalent circuit. The motion-induced noise theory is introduced in 2.1, and the structure with material of the sensor is explained in 2.2, and the RLCG transmission model of the antenna cable is in 2.3. The detail description of the methodology is added in 2.1-2.3, such as “In contrast to magnetic antennas [14], the helix coil sensors comprise of a metal coil, a low-noise amplifier, and a filter with an air core, as illustrated in Figure 1. A typical configuration of 1000mm-long differentially twisted wire is coiled axially along the antenna with 80 turns. This transmission structure can be seen as a short circuit at the end and a low noise amplifier (LNA) at the beginning. Two electrodes are mounted at both ends of the antenna, respectively 20mm from the helix coil sensors, receiving ELF/SLF signals.”, “From equation (2), the motion induced voltage is proportional to turns of helix coils. However, turns per unit length cannot be infinite, where the upper limit depends on the density of the antenna cable. According to the actual engineering positive buoyancy requirements, the cable density is about 0.6-0.8. Therefore, it is necessary to optimize the turns of helix coil sensors according to the material, radius, wire diameter and other parameters.” etc. The content of the relevant title has been revised, such as “Figure 1. Helix coil sensors structure conformal to the towed antenna.”, “Figure 3. Cross-section of the towed antenna with helix coil sensors.” and etc.
Point 7: C. Overall assessment. The work presented here is very interesting and has potential for further developments. In my opinion it must be checked again before a decision can be made.
Response 7: Thanks very much for your comments. Our team has received support from the Naval Advanced Research (grant number 3020907) to improve the existing towed antenna for undersea ELF/SLF communication. The proposed method of helix coil sensors has been used for noise cancellation, supporting subsequent equipment development and some scientific explorement undersea.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Manuscript review No: electronics-2308509 R1
Title: Motion-Induced Noise Detection of Electrode-Pair Towed Antennas Using Helix Coil Sensors
Authors: Xu Xie, Hao Zuo, Shize Wei and Qin Wu
A. Overview
1. In this manuscript the authors present a theoretical and experimental study on a method for detecting the motion-induced noise of electrode-pair towed antennas using helix coil sensors .
2. The contents are expressed clearly; the manuscript is well-organized
B. Overall assessment
The work presented here is very interesting and has potential for further developments
- The authors answered all questions and queries and modified the manuscript according to the reviewers comments.
- In my opinion the manuscript can be published in electronics/mdpi
C. Review Criteria
1. Scope of Journal
Rating: Medium
2. Novelty and Impact
Rating: Medium
3. Technical Content
Rating: Medium
4. Presentation Quality
Rating: Medium
