M-DGPS: mobile devices supported differential global positioning system algorithm

Abstract

Differential global positioning system (DGPS) is important for all kinds of navigation applications which can improve the positioning accuracy from around 15 m provided by standard point service (SPS) to about 1-2 m. It uses a network of continuous operating reference station (CORS) with known positions and broadcasts the correction between the measured satellite pseudoranges and actual (internally computed) pseudoranges, and receiver stations may correct their pseudoranges by the same amount. Hence, in order to implement DGPS, the raw pseudorange measurements of the receiver are required. It is not a problem for general GPS receivers, but for mobile devices with an integrated GPS chip, it is not feasible as the raw pseudorange measurements cannot be accessed for most mobile devices. In order to realize DGPS on mobile, a mobile DGPS (M-DGPS) algorithm is proposed which does not require the raw pseudorange measurements. As the mobile can provide a SPS solution and the satellite names which is used to get the solution, with the correction of these satellites received from the CORS network, a position correction can be calculated. Then, the solution can be improved after applying the position correction. The algorithm is tested in different areas of Fuzhou city, China, and the results show that the new M-DGPS algorithm can improve the positioning accuracy obviously and meet the accuracy requirements of some navigation and surveying applications most of the time in urban environments.

Assessment of the Positioning Accuracy of DGPS and EGNOS Systems in the Bay of Gdansk using Maritime Dynamic Measurements

“…Officially, DGPS must ensure a measurement precision (p = 0·95) of up to 10 m in a horizontal plane in accordance with a standard issued by the International Association of Lighthouse Authorities (IALA) (IALA, 2004). However, in reality, DGPS systems, as has been mentioned before, enable positioning with an accuracy considerably exceeding that of unaugmented GPS, which enables its use, for example, in the location of mobile devices (Ji et al, 2015; Yoon et al, 2016), marine navigation, and in coastal navigation and in dynamic vessel positioning (Chen et al, 2009; Kim, 2014; Moore et al, 2001), in precision farming for reliable yield mapping or crop soil variability (Liu et al, 2015), in hydrography for positioning of acoustic systems (Lubis et al, 2017; Ratheesh et al, 2018; Ward et al, 2016) in autonomous vehicle positioning (Rathour et al, 2017; Ssebazza and Pan, 2015; Vetrella et al, 2016), and in studying glacier changes (Muhammad and Tian, 2015) and in, for example, dam displacements (Galan-Martin et al, 2013).…”

Smart Device-Supported BDS/GNSS Real-Time Kinematic Positioning for Sub-Meter-Level Accuracy in Urban Location-Based Services

“…[11,25]. Therefore, obtaining the required observations is a prerequisite for achieving RTK positioning on smart devices.…”

“…Precise positioning and navigation based on low-cost receivers also becomes possible with the support of multi-constellations [7,8,9,10]. However, the positioning accuracy provided by the commonly used smart devices, such as smartphones with an embedded GNSS chip, is only about 15–20 m through the single-point positioning (SPP) approach [11], and it is very difficult to meet the demands of high-precision LBS, which usually requires sub-meter-level positioning [12,13]. …”

A New DGNSS Positioning Infrastructure for Android Smartphones

“…However, buildings or trees on the path from the satellite to the user can block the GNSS signals, and the reference station and users would utilize different sets of satellites. Thus, the conventional position correction degrades the accuracy of GNSS most of the time, instead of improving the accuracy [16][17][18].…”

“…The concept of DGNSS based on National Marine Electronics Association (NMEA) messages was first proposed in [17], and subsequently demonstrated in [18,19]. These research efforts have shown that the positioning accuracy of smartphones can be improved in mid-latitude regions, and have demonstrated the feasibility of the concept.…”