An Observation Density Based Method for Independent Baseline Searching in GNSS Network Solution

Round 1

Reviewer 1 Report

This article proposes a baseline selection method based on the co-visual density of GNSS satellites, which provides a new option for the setup of GNSS large network solution. Comments on the article are as follows.

1, Among the independent baseline selection strategies, in addition to OBS-MAX, SHORTEST and the method proposed by the authors, there are other models based on maximum ambiguity fixed success rate [1] and STAR [2]. In the results and discussion session, the advantages of the new methods over them, or why the old methods are not applicable in the large global network solution should be analyzed.

2, From Table 2, it can be seen that the probability of large error for OBS-DEN is high (0.07%), which may be due to the fact that some stations with low observation density were left behind by MST to be selected last. Therefore, the advantage of OBS-DEN may lie in the fact that it leads to a better solution for local dense co-viewing. The advantage of OBS-DEN over traditional methods may be better reflected in its ability to exclude stations with both long distances and few observations. This analysis should be considered in appropriate part of the article.

3, In section 4.1, the specific download websites for the products and data mentioned should be added so that the reader can track this study.

4. In the Introduction and Results, Discussion section, some of the language is wordy. The presentation should be more condensed to enhance the readability of the article.

Refs:

1.         Hua, C. Application Research of Method of Large Network Realtime Data Rapid Solution (D). Wuhan, 2010 .

2.         Dach, R.; Walser, P. Bernese GNSS Software Version 5.2; University of Bern: Bern, 2015.

Author Response

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Reviewer 2 Report

This communication falls within the topics covered by the newspaper and is of an adequate length. The topic is of interest however authors should emphasize in greater detail what the contribution of their communication is.

Another doubt relates to the age of the data used: why did the authors focus on data from 10 years ago?

In the last 10 years, satellite navigation systems have made great strides.

It would be much more interesting to refer to newer data.

The last observation relates to the histograms shown.

The histograms shown in figures 4 and 7 must also be improved as regards the caption. In particular, figure 7 states that "The vertical coordinate represents the number of stations in the interval" while the probability label is shown on the ordinate axis.

It needs to be clarified which type of normalization was used to calculate the histograms.

Author Response

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Reviewer 3 Report

I send the review in the attachment.

Comments for author File: Comments.pdf

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Round 2

Reviewer 2 Report

I understand the authors' impossibility of being able to use more recent data but still it is quite strange to publish a research in 2022 on such old data.

Despite this, communication has improved. It remains only to improve figures. Readers must be able to read the figures without having to refer to the text

Figure 4.  What is meant by coordinate-axis.
Please change Y-axis label. Number of what?

Figure 7 please improve caption. Is log scal used? Please improve

Author Response

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