Performance Evaluation of PPP-AR Method for Engineering Surveys with Embedded GNSS Chipset in a Smartphone

2020 ◽  
Author(s):  
Caneren Gul ◽  
Taylan Ocalan ◽  
Nursu Tunalioglu
Keyword(s):  
Satellite System ◽  
Time Interval ◽  
Dual Frequency ◽  
Economic Market ◽  
The World ◽  
Positioning Method ◽  
Gnss Receivers ◽  
Point Positioning ◽  
Global Navigation Satellite ◽  
Gnss Observations

<p>Today, traditional Precise Point Positioning (PPP) method with high-cost geodetic grade Global Navigation Satellite System (GNSS) receivers has been used commonly for surveying, navigation, geodesy, geophysics and other engineering applications where dm-cm level accuracy is required. On the other hand, while smartphones have created a growing economic market in the world, they serve positioning, navigation and timing (PNT) services in varying accuracy levels to the users besides many other facilities. One of the most significant components of the smartphones involving multi-sensors for outdoor point-positioning and navigation is the embedded GNSS chipset. Especially, the world’s first dual-frequency GNSS smartphone produced by Xiaomi in May 2018, so-called Xiaomi Mi 8, brings a new aspect to PNT applications. In this study, a smartphone with dual-frequency embedded GNSS chipset was used to analyze the performance of PPP-Ambiguity Resolution (PPP-AR) method in engineering surveys. With respect to study aim, simultaneous static GNSS observations gathered with a geodetic grade GNSS receiver and a smartphone were conducted within a test setup. The static GNSS observations were repeated for 3 days and the campaign duration was 2 hours per day at the same daily time interval. All the raw GNSS observations were converted into Receiver Independent Exchange Format (RINEX) and processed by the relative point positioning method as a reference solution initially. Later, all observations were processed by the PPP-AR method. A widely used online post-processing GNSS service, namely CSRS-PPP, which was updated in August 2018 (GPSPACE to SPARK) were employed for PPP-AR solutions. As a conclusion, we analyze the performance of the embedded dual frequency GNSS chipset and assess the feasibility of them in different engineering surveys.</p><p><strong>Keywords:</strong> Smartphone Positioning, PPP-AR, Embedded GNSS Chipset, Dual-frequency, Engineering Surveys</p>

scholarly journals Ionosphere-Constrained Single-Frequency PPP with an Android Smartphone and Assessment of GNSS Observations

Sensors ◽  
2020 ◽  
Vol 20 (20) ◽  
pp. 5917
Author(s):  
Guangxing Wang ◽  
Yadong Bo ◽  
Qiang Yu ◽  
Min Li ◽  
Zhihao Yin ◽  
...  
Keyword(s):  
Single Point ◽  
Application Programming Interface ◽  
Satellite System ◽  
Single Frequency ◽  
Dual Frequency ◽  
Application Programming ◽  
Point Positioning ◽  
Global Navigation Satellite ◽  
Gnss Observations ◽  
Better Than

With the development of Global Navigation Satellite System (GNSS) and the opening of Application Programming Interface (API) of Android terminals, the positioning research of Android terminals has attracted the attention of GNSS community. In this paper, three static experiments were conducted to analyze the raw GNSS observations quality and positioning performances of the smartphones. For the two experimental smartphones, the numbers of visible satellites with dual-frequency signals are unstable and not enough for dual-frequency Precise Point Positioning (PPP) processing all through the day. Therefore, the ionosphere-constrained single-frequency PPP model was employed to improve the positioning with the smartphones, and its performance was evaluated and compared with those of the Single Point Positioning (SPP) and the traditional PPP models. The results show that horizontal positioning accuracies of the smartphones with the improved PPP model are better than 1 m, while those with the SPP and the traditional PPP models are about 2 m.

scholarly journals Real-time Precise Point Positioning with a Xiaomi MI 8 Android Smartphone

Sensors ◽  
2019 ◽  
Vol 19 (12) ◽  
pp. 2835 ◽  
Author(s):  
Bo Chen ◽  
Chengfa Gao ◽  
Yongsheng Liu ◽  
Puyu Sun
Keyword(s):  
Real Time ◽  
Mobile Phones ◽  
Precise Point Positioning ◽  
Satellite System ◽  
Dual Frequency ◽  
Gnss Positioning ◽  
Positioning Errors ◽  
Positioning Method ◽  
Point Positioning ◽  
Time Required

The Global Navigation Satellite System (GNSS) positioning technology using smartphones can be applied to many aspects of mass life, and the world’s first dual-frequency GNSS smartphone Xiaomi MI 8 represents a new trend in the development of GNSS positioning technology with mobile phones. The main purpose of this work is to explore the best real-time positioning performance that can be achieved on a smartphone without reference stations. By analyzing the GNSS raw measurements, it is found that all the three mobile phones tested have the phenomenon that the differences between pseudorange observations and carrier phase observations are not fixed, thus a PPP (precise point positioning) method is modified accordingly. Using a Xiaomi MI 8 smartphone, the modified real-time PPP positioning strategy which estimates two clock biases of smartphone was applied. The results show that using multi-GNSS systems data can effectively improve positioning performance; the average horizontal and vertical RMS positioning error are 0.81 and 1.65 m respectively (using GPS, BDS, and Galileo data); and the time required for each time period positioning errors in N and E directions to be under 1 m is less than 30s.

scholarly journals Application of Least Squares with Conditional Equations Method for Railway Track Inventory Using GNSS Observations

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4948
Author(s):  
Krzysztof Czaplewski ◽  
Zbigniew Wisniewski ◽  
Cezary Specht ◽  
Andrzej Wilk ◽  
Wladyslaw Koc ◽  
...  
Keyword(s):  
Measurement Data ◽  
Satellite System ◽  
Theoretical Description ◽  
Railway Track ◽  
Land Surveying ◽  
Gnss Receivers ◽  
Mobile Satellite ◽  
Global Navigation Satellite ◽  
Gnss Observations ◽  
Observation Results

Satellite geodetic networks are commonly used in surveying tasks, but they can also be used in mobile surveys. Mobile satellite surveys can be used for trackage inventory, diagnostics and design. The combination of modern technological solutions with the adaptation of research methods known in other fields of science offers an opportunity to acquire highly accurate solutions for railway track inventory. This article presents the effects of work carried out using a mobile surveying platform on which Global Navigation Satellite System (GNSS) receivers were mounted. The satellite observations (surveys) obtained were aligned using one of the methods known from classical land surveying. The records obtained during the surveying campaign on a 246th km railway track section were subjected to alignment. This article provides a description of the surveying campaign necessary to obtain measurement data and a theoretical description of the method employed to align observation results as well as their visualisation.

scholarly journals Study on Multi-GNSS Precise Point Positioning Performance with Adverse Effects of Satellite Signals on Android Smartphone

Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6447
Author(s):  
Hongyu Zhu ◽  
Linyuan Xia ◽  
Dongjin Wu ◽  
Jingchao Xia ◽  
Qianxia Li
Keyword(s):  
Adverse Effects ◽  
Precise Point Positioning ◽  
Phase Error ◽  
Three Dimensional ◽  
Satellite System ◽  
Dual Frequency ◽  
Positioning Accuracy ◽  
Noise Ratio ◽  
Point Positioning ◽  
Gnss Observations

The emergence of dual frequency global navigation satellite system (GNSS) chip actively promotes the progress of precise point positioning (PPP) technology in Android smartphones. However, some characteristics of GNSS signals on current smartphones still adversely affect the positioning accuracy of multi-GNSS PPP. In order to reduce the adverse effects on positioning, this paper takes Huawei Mate30 as the experimental object and presents the analysis of multi-GNSS observations from the aspects of carrier-to-noise ratio, cycle slip, gradual accumulation of phase error, and pseudorange residual. Accordingly, we establish a multi-GNSS PPP mathematical model that is more suitable for GNSS observations from a smartphone. The stochastic model is composed of GNSS step function variances depending on carrier-to-noise ratio, and the robust Kalman filter is applied to parameter estimation. The multi-GNSS experimental results show that the proposed PPP method can significantly reduce the effect of poor satellite signal quality on positioning accuracy. Compared with the conventional PPP model, the root mean square (RMS) of GPS/BeiDou (BDS)/GLONASS static PPP horizontal and vertical errors in the initial 10 min decreased by 23.71% and 62.06%, respectively, and the horizontal positioning accuracy reached 10 cm within 100 min. Meanwhile, the kinematic PPP maximum three-dimensional positioning error of GPS/BDS/GLONASS decreased from 16.543 to 10.317 m.

scholarly journals Single-Baseline RTK Positioning Using Dual-Frequency GNSS Receivers Inside Smartphones

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4302 ◽  
Author(s):  
Paolo Dabove ◽  
Vincenzo Di Pietra
Keyword(s):  
Satellite System ◽  
Smart Devices ◽  
Dual Frequency ◽  
Cooperative Positioning ◽  
Gnss Positioning ◽  
Gnss Receivers ◽  
Master Station ◽  
Single Baseline ◽  
Gnss Measurements ◽  
Global Navigation Satellite

Global Navigation Satellite System (GNSS) positioning is currently a common practice thanks to the development of mobile devices such as smartphones and tablets. The possibility to obtain raw GNSS measurements, such as pseudoranges and carrier-phase, from these instruments has opened new windows towards precise positioning using smart devices. This work aims to demonstrate the positioning performances in the case of a typical single-base Real-Time Kinematic (RTK) positioning while considering two different kinds of multi-frequency and multi-constellation master stations: a typical geodetic receiver and a smartphone device. The results have shown impressive performances in terms of precision in both cases: with a geodetic receiver as the master station, the reachable precisions are several mm for all 3D components while if a smartphone is used as the master station, the best results can be obtained considering the GPS+Galileo constellations, with a precision of about 2 cm both for 2D and Up components in the case of L1+L5 frequencies, or 3 cm for 2D components and 2 cm for the Up, in the case of an L1 frequency. Moreover, it has been demonstrated that it is not feasible to reach the phase ambiguities fixing: despite this, the precisions are still good and also the obtained 3D accuracies of positioning solutions are less than 1 m. So, it is possible to affirm that these results are very promising in the direction of cooperative positioning using smartphone devices.

Performance Analysis of GPS/GLONASS Precise Point Positioning

GEOMATICA ◽  
2013 ◽  
Vol 67 (4) ◽  
pp. 237-242 ◽  
Author(s):  
Mohamed Azab ◽  
Ahmed El-Rabbany ◽  
M. Nabil Shoukry ◽  
Ramadan Khalil ◽  
Akram Afifi
Keyword(s):  
Precise Point Positioning ◽  
Satellite System ◽  
Data Sets ◽  
Dual Frequency ◽  
International Gnss Service ◽  
Positioning Systems ◽  
Processing Strategies ◽  
Satellite Visibility ◽  
Point Positioning ◽  
Global Navigation Satellite

Precise Point Positioning (PPP) with Global Positioning Systems (GPS) has attracted the attention of many researchers over the past decade. Recently, the Russian global navigation satellite system (GLONASS) has been modernized and restored to near full constellation status, which has made it more attractive for positioning and navigation. Having two healthy systems, namely GPS and GLONASS provides a combination of both constellations, which in turn promises to improve the availability, positioning accuracy, and reliability of PPP solutions. This study investigates the effect of combining GPS and GLONASS dual-frequency measurements on the static PPP solution and its sensitivity to different processing strategies. Many data sets from five globally distributed International GNSS Service (IGS) tracking stations were processed using the Bernese GPS software package. The addition of GLONASS constellation improved the satellite visibility and geometry by more than 60%, and 40%, respectively, and improves the positioning convergence by up to 41%, 38%, and 19% in east, north, and up directions, respectively.

Evaluation and Application of the GPS Code Observable in Precise Point Positioning

2019 ◽  
Vol 72 (06) ◽  
pp. 1633-1648
Author(s):  
Haojun Li ◽  
Jingxin Xiao ◽  
Bofeng Li
Keyword(s):  
Precise Point Positioning ◽  
Satellite System ◽  
Convergence Time ◽  
The North ◽  
Global Positioning ◽  
Gnss Receivers ◽  
Point Positioning ◽  
Global Navigation Satellite ◽  
Accumulation Characteristic ◽  
Better Than

The accuracy of the Global Positioning System (GPS) observable, especially for the code observable, has improved with the development of Global Navigation Satellite System (GNSS) receiver technology. An evaluation of the GPS code observable is presented in this paper, together with a stochastic model for the code and phase observables in Precise Point Positioning (PPP), established using the evaluated results. The results show that the code observables of Leica GNSS receivers are generally better than those of some other brand receivers and the Root Mean Square (RMS) for the code observables of the Leica GRX1200PRO, which includes the multipath effect, reaches 0·71 m, although Coarse/Acquisition (C/A) code observables are tracked. The static positioning of the code observable can reach centimetre level and the convergence time for the JPLM station is just 2·5 hours. The positioning results show that it is difficult to converge the Up direction to the centimetre level, compared with the North and East directions. The results show that static positioning can be correlated with the accumulation characteristic of the error for the code observable, while that that of the kinematic mode can be correlated to the error value. The shortened PPP convergence times verify that the presented stochastic models are effective.

scholarly journals Performance Evaluation of Single-Frequency Precise Point Positioning and Its Use in the Android Smartphone

2021 ◽  
Vol 13 (23) ◽  
pp. 4894
Author(s):  
Min Li ◽  
Zhuo Lei ◽  
Wenwen Li ◽  
Kecai Jiang ◽  
Tengda Huang ◽  
...  
Keyword(s):  
Precise Point Positioning ◽  
Satellite System ◽  
Convergence Time ◽  
Single Frequency ◽  
Dominant Factor ◽  
Smart Devices ◽  
Dual Frequency ◽  
Point Positioning ◽  
Pseudorange Noise ◽  
Global Navigation Satellite

The opening access of global navigation satellite system (GNSS) raw data in Android smart devices has led to numerous studies on precise point positioning on mobile phones, among which single-frequency precise point positioning (SF-PPP) has become popular because smartphone-based dual-frequency data still suffer from poor observational quality. As the ionospheric delay is a dominant factor in SF-PPP, we first evaluated two SF-PPP approaches with the MGEX (Multi-GNSS Experiment) stations, the Group and Phase Ionospheric Correction (GRAPHIC) approach and the uncombined approach, and then applied them to a Huawei P40 smartphone. For MGEX stations, both approaches achieved less than 0.1 m and 0.2 m accuracy in horizontal and vertical components, respectively. Uncombined SF-PPP manifested a significant decrease in the convergence time by 40.7%, 20.0%, and 13.8% in the east, north, and up components, respectively. For P40 data, the SF-PPP performance was analyzed using data collected with both a built-in antenna and an external geodetic antenna. The P40 data collected with the built-in antenna showed lower carrier-to-noise ratio (C/N0) values, and the pseudorange noise reached 0.67 m, which is about 67% larger than that with a geodetic antenna. Because the P40 pseudorange noise presented a strong correlation with C/N0, a C/N0-dependent weight model was constructed and used for the P40 data with the built-in antenna. The convergence of uncombined SF-PPP approach was faster than the GRAPHIC model for both the internal and external antenna datasets. The root mean square (RMS) errors for the uncombined SF-PPP solutions of P40 with an external antenna were 0.14 m, 0.15 m, and 0.33 m in the east, north, and up directions, respectively. In contrast, the P40 with an embedded antenna could only reach 0.72 m, 0.51 m, and 0.66 m, respectively, indicating severe positioning degradation due to antenna issues. The results indicate that the two SF-PPP models both can achieve sub-meter level positioning accuracy utilizing multi-GNSS single-frequency observations from mobile smartphones.

scholarly journals GNSS and LNSS Positioning of Unmanned Transport Systems: The Brief Classification of Terrorist Attacks on USVs and UUVs

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 401
Author(s):  
Łukasz Lemieszewski ◽  
Aleksandra Radomska-Zalas ◽  
Andrzej Perec ◽  
Larisa Dobryakova ◽  
Evgeny Ochin
Keyword(s):  
Propagation Delay ◽  
Satellite System ◽  
Transport Systems ◽  
Terrorist Attacks ◽  
Signal Delay ◽  
Receiving Antenna ◽  
The World ◽  
Gnss Receivers ◽  
Global Navigation Satellite

As the demand for precision positioning grows around the world and spreads across various industries, initiatives are being taken to increasingly protect Global Navigation Satellite System (GNSS) receivers from intruders of all kinds, from unintentional industrial interference to advanced GNSS spoofing systems. The timing and cost of these forthcoming satellite navigation safety efforts are difficult to decipher due to the large number of new signals and constellations being deployed. However, it is safe to say that the newly designed anti-jamming and anti-spoofing GNSS systems open up new opportunities for innovative technologies. The false acoustic signal delay is equal to the sum of the spoofer receiving antenna delay, processing delay, and propagation delay from the spoofer to the victim. The victim finds the same location as the spoofer’s receiving antenna, and receivers located in different locations will have the same XYZ. The article presents classifications of terrorist attacks of this type.

Sign in / Sign up

Export Citation Format

Share Document