Assessing the accuracy of online GNSS processing services and commercial software on short baselines

Abstract

With the rapid establishment of free online processing services to provide users with reliable solutions, it is important to determine the reliability of using free online processing software for the Global Navigation Satellite System post-processing. The study aim at assessing the accuracy of two (2) free online processing software, AUSPOS, and CSRS-PPP and two (2) commercial software, compass post-processing, and GNSS solutions. Field observations were carried out on seven (7) control points using static GNSS observation techniques with an observation period of 1hr for three (3) consecutive days and conventional surveying using total station instruments to establish a closed traverse. The acquired data were post-processed using both online and commercial software. The co-ordinates generated from each software were then compared with the ones obtained using total station instruments to determine their relative discrepancies and accuracies. Root mean square error and T-test were used for the analysis of the result. The result obtained is (0.004m, 0.003m and 0.007m) for compass post-processing software and (0.015m, 0.012m and 0.016m) for GNSS solutions software and the online software had the Root Mean Square Error (RMSE) values of (0.025m, 0.023m and 0.027m) for AUSPOS and (0.034m, 0.037m and 0.041m) for CSRS-PPP both in X, Y, and Z direction i.e. UTM East, North and ellipsoidal height respectively. Analysis at a 5% level of significance shows no significant difference between the two methods. Online GNSS processing services are easy to use, do not require the knowledge of GNSS data processing and can be adopted for engineering and geodetic applications.

Comparison of PPPH MATLAB based program vs Online GNSS Services

“…The main goal in developing GAPS was to come up with a state-of-the-art positioning tool; however, GAPS showed itself to be much more versatile than that, allowing innovative data analysis and quality control procedures. [5] 2.2 CSRS-PPP CSRS-PPP provides an online service for GNSS data post-processing allowing users to compute high precision positions from their raw observed data. CSRS estimates are computed from carrier phase or code pseudo-range observations of both single and dual-frequency receivers.…”

Precision Evaluation for Different GNSS Rinex 3 Using Online Services and Open-Source Software PPP-Mans

“…As a result, using conventional techniques to build and maintain a network of permanent stations is expensive. On the other side, the International GNSS Service (IGS) provides incredibly precise satellite orbits, clock corrections, or atmospheric products (Herbert et al, 2020).…”

“…It is crucial to use this form of differential placement when prompt results are desired. The post-processing techniques perform the modifications after acquiring the GPS data (Herbert et al, 2020).If the data was gathered using a double frequency GNSS receiver and viewed from any position on Earth, the data RINEX file can be sent to online services for postprocessing. Some services also offer a wide range of data types.…”

“…It is crucial to use this form of differential placement when prompt results are desired. The post-processing techniques perform the modifications after acquiring the GPS data (Herbert et al, 2020).…”

Khảo sát kết quả xử lý dữ liệu GNSS sử dụng các dịch vụ trực tuyến

“…Khả năng xử lý của các dịch vụ AusPOS, CRCS-PPP cũng đã được đánh giá khi so sánh với kết quả xử lý bằng các phần mềm thương mại xử lý cạnh ngắn như Compass Post Process và GNSS Solution. Kết quả thực nghiệm cho thấy, với mức khác biệt 5% về độ chính xác trong kết quả xử lý giữa các dịch vụ xử lý dữ liệu trực tuyến với các phần mềm thương mại chứng tỏ tính hiệu quả của các dịch vụ nêu trên [14]. Nghiên cứu [15] đã đánh giá kết quả xử lý dữ liệu GNSS sử dụng các dịch vụ AusPOS, OPUS, CRCS-PPP với Magic-GNSS và cho độ chính xác kết quả đạt được ở mức cm khi xử lý dữ liệu với độ dài 3 giờ.…”