Towards Smarter Positioning through Analyzing Raw GNSS and Multi-Sensor Data from Android Devices: A Dataset and an Open-Source Application
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe paper presents a dataset of GNSS measurements from a number of smartphones and smartwatches, as well as apps and software to record and analyze data from those devices. Precise positioning and navigation with smartphones and other mobile devices is a hot topic and it is thus nice to have good datasets. I think the paper describe the dataset well and is quite interesting. Maybe it would be worth discussing the results in more detail.
Two small comments:
Table 3, entry for S2: It could be made clearer what dates correspond to what phones.
Line 466: “speed of light”. I guess it should be the wavelength.
Author Response
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Thank you for your review of our article. Please find in the file attached our detailed answer to your comments.
This file also includes a version of the manuscript with changes highlighted in blue.
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Reviewer 2 Report
Comments and Suggestions for AuthorsThe article is interesting, well written and the topics covered perfectly coincide with the scope of the Journal. In my opinion, one way to make the article even more interesting and easily to consult is to move some of the figures and tables listed in the appendix to the paragraphs to which they refer
Author Response
Dear Sir or Madam,
Thank you for your review of our article. Please find in the file attached our detailed answer to your comments.
This file also includes a version of the manuscript with changes highlighted in blue.
Best regards,
The Authors
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors
Review of the article “Towards Smarter Positioning through Analyzing Raw GNSS and Multi-Sensor Data from Android Devices:A Dataset and an Open-Source Application”
In this paper authors propose a first analysis of the data logged and evaluate the data according to several performance metrics. A discussion reviewing the capacities of smart devices for advanced positioning is proposed, as well as the current open challenges
General thoughts
The article presents interesting research and very well prepared. Test procedure is clear and justified, study data are rightly chosen and sufficient, authors correctly described the study. It is important that the test procedure can be reproduced by other researchers. The following detailed comments are intended to correct some of the shortcomings of the article.
Detailed comments
Text is written in a logical and thoughtful way, creating a coherent whole, in accordance with the writing regime of scientific paper (IMRaD). The method of presentation, comprehensive introduction and very interesting and thoughtful practical examples deserve praise. Below a comments for corrections:
1) In my opinion title is too long: “less means more”. A proper, shorten title might increase visibility in a future
2) I recommend add 2-3 keywords, e.g. smartphone, androind, etc. and changing phreases “Global Navigation Satellite System, Global Positioning System” into GNSS, GPS
3) It’s worth to extend literature by other authors works dealing with a GNSS clocks in general:
a) Hernandez-Orallo, Enrique, Pietro Manzoni, Carlos Tavares Calafate, and Juan Carlos Cano. 2020. “Evaluating How Smartphone Contact Tracing Technology Can Reduce the Spread of Infectious Diseases: The Case of COVID-19.” IEEE Access 8: 99083–97. https://doi.org/10.1109/ACCESS.2020.2998042.
b) Magiera, Weronika, Inese Vārna, Ingus Mitrofanovs, Gunārs Silabrieds, Artur Krawczyk, Bogdan Skorupa, Michal Apollo, and Kamil Maciuk. 2022. “Accuracy of Code GNSS Receivers under Various Conditions.” Remote Sensing 14 (11): 2615. https://doi.org/10.3390/rs14112615.
c) Karki, Bikram, and Myounggyu Won. 2020. “Characterizing Power Consumption of Dual-Frequency GNSS of Smartphone.” In GLOBECOM 2020 - 2020 IEEE Global Communications Conference, 1–6. IEEE. https://doi.org/10.1109/GLOBECOM42002.2020.9322317.
4) Whole text is definitely to long, I suggest make it shorter in some parts: 37 pages, even including attachments is to long.
Text might be accepted for a publication after improvements.
All the best and stay safe
Author Response
Dear Sir or Madam,
Thank you for your review of our article. Please find in the file attached our detailed answer to your comments.
This file also includes a version of the manuscript with changes highlighted in blue.
Best regards,
The Authors
Author Response File: Author Response.pdf
Reviewer 4 Report
Comments and Suggestions for AuthorsVery interesting paper and the logging APP and datasets provided in this paper could significantly help more researchers investigating the possibility of utilizing smart devices for positioning, navigation services.
Major Comments
1/ Line 512-515: the manuscript mentions that in certain cases, some devices have even reported more satellites than the reference receiver as these devices do not remove low quality signals. It would be great to have a sentence or two to describe how the positioning performance is with and without these bad signals.
2/ There are tons of results shown in the appendix. However, the results section in the manuscript only discussed a bit. Since these results are very informative, it would be great for the authors to discuss the results for each scenario in details and have some conclusions/observations on the performance comparison among different devices and why.
3/ Table A.5, A.12, A17, A23 shows the error for east, north, and up for each device. It would be great to have an overall root mean square error metric over all dimensions that quantifies the performance of each device. This could help reader to better understand/order the performance of the devices.
4/ In this paper, the author considers two mode: texting and pocket. It would be great to have some further ablation studies to understand the impact of the position of the devices. For example, is the performance comparable if the screen side faces front or back in the pocket? How's the performance for different angles of holding the devices? This can be considered as a future work.
5/ Figure A16, A17, for the doppler errors and phase errors, seems the mean errors are all positive across all devices. Any insights on this?
Comments on the Quality of English Language
The overall quality of the writing is satisfactory.
Author Response
Dear Sir or Madam,
Thank you for your review of our article. Please find in the file attached our detailed answer to your comments.
This file also includes a version of the manuscript with changes highlighted in blue.
Best regards,
The Authors
Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
Comments and Suggestions for AuthorsText might be accepted for a publication in a current form.
