Real-Time Kinematic (RTK) and Differential Global Navigation Satellite System (DGNSS) corrections using multiple reference stations

Abstract

A real-time kinematic (RTK) and / or differential GNSS (DGNSS) system is disclosed in which correction data from multiple reference stations is provided to a mobile device. Selection of the reference station (from which correction data is provided to the mobile device) may be based on factors such as the approximate location of the mobile device, the geometry of the reference station, and / or other factors. The mobile device can combine the correction data from the multiple reference stations in various ways to determine an accurate position fix for the mobile device without having to interpolate the correction data from the multiple reference stations.

Description

[Technical field]

[0001] The present invention relates generally to the field of satellite-based positioning, and more particularly to error correction in Global Navigation Satellite System (GNSS) terms for more accurate position determination. [Background technology]

[0002] A precise positioning service (PPS) provides highly accurate meter-level or sub-meter-level positioning of a mobile device, exceeding the accuracy of conventional consumer-grade Global Navigation Satellite System (GNSS) receivers. PPS includes services such as Precise Point Positioning (PPP), Real-Time Kinematic (RTK), and Differential GNSS (DGNSS). These services often perform network-based interpolation of reference station data to provide correction data (e.g., reference measurements) to a mobile station for positioning, and vary in accuracy, availability, and reliability. For highly accurate position determination of a mobile device, a conventional PPS may take a relatively long time (e.g., several minutes or more). In many conventional applications, such as land surveying, faster position determination may not be required. However, PPS may be useful in various modern applications if it can provide a relatively fast determination of highly accurate position. Summary of the Invention [Means for solving the problem]

[0003] The embodiments described herein below address these and other problems by providing an RTK / DGNSS system in which correction data from multiple reference stations is provided to a mobile device. In particular, the selection of a reference station may be made based on factors such as the approximate location of the mobile device, the geometry of the reference stations, and / or other factors. The mobile device may combine the correction data from the multiple reference stations in any of a variety of ways to determine a precise position fix for the mobile device. The selection of a reference station may be made by a service provider communicatively coupled to the mobile device via any combination of public and / or private networks.

[0004] An exemplary method of providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections according to the present disclosure comprises receiving information indicative of an approximate location of the mobile device or information regarding a satellite vehicle line-of-sight to the mobile device. The method also comprises selecting a plurality of reference stations from which to obtain the reference station correction data, where the selecting is based at least in part on the approximate location of the mobile device or information regarding the satellite vehicle line-of-sight to the mobile device. The method also comprises obtaining the reference station correction data from each reference station of the plurality of reference stations, where for each reference station, the reference station correction data may comprise data based on one or more measurements acquired by a GNSS receiver at the respective reference station. The method also comprises sending the reference station correction data to the mobile device.

[0005] An exemplary method of applying real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections at a mobile device according to the present disclosure comprises acquiring at the mobile device reference station correction data from each of a plurality of reference stations, where for each reference station, the reference station correction data may comprise one or more measurements acquired by a GNSS receiver at the respective reference station. The method also comprises acquiring mobile device measurement data, where the mobile device measurement data may comprise one or more measurements acquired by the GNSS receiver at the mobile device. The method also comprises determining a position of the mobile device based on the reference station correction data from each of the plurality of reference stations and the mobile device measurement data.

[0006] An exemplary computer server for providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections according to the present disclosure comprises a transceiver, a memory, and one or more processing units communicatively coupled to the transceiver and the memory. The one or more processing units are configured to receive information indicative of an approximate location of the mobile device or information regarding a satellite vehicle visible to the mobile device. The one or more processing units are further configured to select a plurality of reference stations from which to obtain the reference station correction data, where the selecting is based at least in part on the approximate location of the mobile device or information regarding the satellite vehicle visible to the mobile device. The one or more processing units are further configured to obtain the reference station correction data from each of the plurality of reference stations, where for each reference station, the reference station correction data may comprise data based on one or more measurements acquired by a GNSS receiver at the respective reference station. The one or more processing units are further configured to send the reference station correction data to the mobile device via the transceiver.

[0007] An exemplary mobile device for applying real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections according to the present disclosure comprises a transceiver, a GNSS receiver, a memory, and one or more processing units communicatively coupled to the transceiver, the GNSS receiver, and the memory. The one or more processing units are configured to acquire reference station correction data from each of a plurality of reference stations via the transceiver, where for each reference station, the reference station correction data may comprise one or more measurements acquired by the GNSS receiver at the respective reference station. The one or more processing units are also configured to acquire mobile device measurement data, where the mobile device measurement data may comprise one or more measurements acquired by the GNSS receiver of the mobile device. The one or more processing units are also configured to determine a position of the mobile device based on the reference station correction data from each of the plurality of reference stations and the mobile device measurement data.

[0008] An exemplary device for providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections according to the present disclosure comprises means for receiving information indicative of an approximate location of the mobile device or information regarding a satellite vehicle line-of-sight to the mobile device. The device also comprises means for selecting a plurality of reference stations from which to obtain reference station correction data, where the selecting is based at least in part on the approximate location of the mobile device or information regarding the satellite vehicle line-of-sight to the mobile device. The device also comprises means for obtaining reference station correction data from each of the plurality of reference stations, where for each reference station, the reference station correction data may comprise data based on one or more measurements acquired by a GNSS receiver at the respective reference station. The device also comprises means for sending the reference station correction data to the mobile device.

[0009] An exemplary device for applying real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections at a mobile device according to the present disclosure comprises means for acquiring at the mobile device reference station correction data from each of a plurality of reference stations, where for each reference station, the reference station correction data may comprise one or more measurements acquired by a GNSS receiver at the respective reference station. The device also comprises means for acquiring mobile device measurement data, where the mobile device measurement data may comprise one or more measurements acquired by the GNSS receiver at the mobile device. The device also comprises means for determining a position of the mobile device based on the reference station correction data from each of the plurality of reference stations and the mobile device measurement data.

[0010] An exemplary non-transitory computer-readable medium according to the present disclosure stores instructions for providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections. The instructions comprise code for receiving information indicative of an approximate location of the mobile device or information about a satellite vehicle line-of-sight to the mobile device. The instructions also comprise code for selecting a plurality of reference stations from which to obtain reference station correction data, where the selecting is based at least in part on the approximate location of the mobile device or information about the satellite vehicle line-of-sight to the mobile device. The instructions also comprise code for obtaining reference station correction data from each of the plurality of reference stations, where for each reference station, the reference station correction data may comprise data based on one or more measurements acquired by a GNSS receiver at the respective reference station. The instructions also comprise code for sending the reference station correction data to the mobile device.

[0011] An exemplary non-transitory computer-readable medium according to the present disclosure stores instructions for applying real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections at a mobile device. The instructions comprise code for acquiring at the mobile device reference station correction data from each reference station of a plurality of reference stations, where for each reference station, the reference station correction data may comprise one or more measurements acquired by a GNSS receiver at the respective reference station. The instructions also comprise code for acquiring mobile device measurement data, where the mobile device measurement data may comprise one or more measurements acquired by a GNSS receiver at the mobile device. The instructions also comprise code for determining a position of the mobile device based on the reference station correction data from each reference station of the plurality of reference stations and the mobile device measurement data. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic diagram of a real-time kinematic (RTK) and differential GNSS (DGNSS) system according to one embodiment. [Diagram 2] 1 is a diagram of an overhead view of a mobile device and multiple reference stations illustrating an algorithm that may be used for base station selection, according to some embodiments. [Diagram 3] 1 is a diagram of an overhead view of a mobile device and multiple reference stations illustrating an algorithm that may be used for base station selection, according to some embodiments. [Figure 4] 1 is an exemplary skyplot illustrating the azimuths and altitudes of various satellites visible (observable) by reference stations R1 and R2. [Diagram 5] 1 is a diagram illustrating how data from different reference stations may be provided to different mobile devices based on their respective locations within an area serviced by a mobile carrier network, according to one embodiment. [Figure 6]4A-4C are timing diagrams of various scheduling methods according to one embodiment. [Figure 7] 1 is a diagram of an overhead view of a mobile device and multiple reference stations illustrating values ​​that may be derived from reference station correction data and used to perform a data integrity check, according to one embodiment. [Figure 8] 1 is a diagram of an overhead view of a mobile device and multiple reference stations illustrating values ​​that may be derived from reference station correction data and used to perform a data integrity check, according to one embodiment. [Figure 9A] FIG. 1 is a flow diagram of a method for providing reference station correction data to a mobile device for RTK or DGNSS corrections in accordance with various embodiments. [Figure 9B] FIG. 1 is a flow diagram of a method for providing reference station correction data to a mobile device for RTK or DGNSS corrections in accordance with various embodiments. [Figure 10A] FIG. 1 is a flow diagram of a method for applying RTK or DGNSS corrections in a mobile device in accordance with various embodiments. [Figure 10B] FIG. 1 is a flow diagram of a method for applying RTK or DGNSS corrections in a mobile device in accordance with various embodiments. [Figure 10C] FIG. 1 is a flow diagram of a method for applying RTK or DGNSS corrections in a mobile device in accordance with various embodiments. [Figure 11] FIG. 2 is a block diagram of a mobile device according to one embodiment. [Figure 12] FIG. 1 is a block diagram of one embodiment of a computer system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] According to some exemplary implementations, like reference numbers in various figures refer to like elements. In addition, multiple instances of an element may be indicated by a first number for that element followed by a letter or a hyphen and a second number. For example, multiple instances of element 110 may be indicated as 110-1, 110-2, 110-3, etc., or 110a, 110b, 110c, etc. When referring to such an element using only the first number, any instance of that element should be understood (e.g., element 110 in the previous example would refer to elements 110-1, 110-2, and 110-3, or elements 110a, 110b, and 110c).

[0014] Several example embodiments will now be described with reference to the accompanying drawings, which form a part of this specification. Specific embodiments in which one or more aspects of the present disclosure may be implemented are described below, but other embodiments may be used and various modifications may be made without departing from the scope of the present disclosure.

[0015] As used herein, the terms "position" and "location" are used interchangeably. Additionally, the terms "position determination," "position fix," "position estimate," "estimated location," "position fix," and the like are also used interchangeably herein with respect to GNSS-based positioning to refer to an estimated position of a mobile device or other device equipped with a GNSS receiver. A position or location may be, for example, a two-dimensional position with respect to a two-dimensional map, or a three-dimensional position.

[0016] Additionally, the term "correction data" as used herein may refer to correction information provided by a RTK service provided to enable accurate position determination of a device having a GNSS receiver. The correction data may include measurement data acquired by a reference station and / or correction information derived from measurement data, such as a difference between a true distance determination based on a known position of the reference station and a measurement acquired at the reference station. The correction data may be used as described herein together with measurements acquired at a device having a GNSS receiver to determine an accurate position of the device.

[0017] 1 is a schematic diagram of a real-time kinematic (RTK) and differential GNSS (DGNSS) system according to one embodiment. The RTK / DGNSS system 100 enables highly accurate (e.g., sub-meter) GNSS position fixes of a mobile device 110 (also called a "rover station" or "rover") by using GNSS receivers at both the mobile device 110 and one or more reference stations 120 (also called "base stations") that receive radio frequency (RF) signals 130 from satellite vehicles (SVs) 140 (GNSS satellites) from one or more GNSS constellations (e.g., Global Positioning System (GPS), Galileo (GAL), Global Navigation Satellite System (GLONASS), Beidou, etc.). The type of mobile device 110 used may vary depending on the application and may include any of various types of devices having access to GNSS positioning data, such as a mobile device equipped with a GNSS receiver. Such mobile devices may include, for example, consumer electronics or other mobile consumer devices, such as mobile phones, tablets, laptops, wearable devices, vehicles, etc. In some embodiments, the mobile device 110 may comprise industrial equipment, such as surveying equipment.

[0018] In GNSS-based positioning, the mobile device 110 can use code-based positioning to determine the distance of each of the SVs 140 based on the determined delay of the generated pseudo-random binary sequence received in the RF signal 130. The mobile device 110 can use ephemeris (or navigation) data for the SVs 140 to more precisely calculate the position of each SV 140 at a particular moment in time. With the distance and position information of the SVs 140, the mobile device 110 can then determine a position fix for its location using conventional GNSS techniques. This position fix may be determined, for example, by a Standalone Positioning Engine (SPE) executed by one or more processors of the mobile device 110. However, the resulting accuracy of the position fix for the mobile device 110 is subject to errors caused by the SVs 140 orbit and clock, ionospheric and tropospheric delays, and other phenomena. While this can provide meter-order accuracy, this accuracy may be insufficient for many applications.

[0019] DGNSS provides an extension to conventional GNSS positioning by providing correction data from a reference station 120 with a known, fixed location. More specifically, the reference station 120 acquires GNSS measurements of RF signals 130 using a highly accurate GNSS receiver, and such GNSS measurements are provided to the mobile device 110 (e.g., via radio broadcast and / or data communication network 150 such as the Internet) together with the known location of the reference station 120. The mobile device can then use the correction data (which may include the measurement data and position information of the reference station 120, or correction information derived therefrom) to extend the GNSS-based positioning by applying corrections to the measured distances (pseudoranges) to each of the SVs 140. This more accurate position fix may be determined, for example, by a Precise Positioning Engine (PPE) executed by one or more processors of the mobile device 110.

[0020] RTK positioning can provide even more accurate solutions (e.g., centimeter or decimeter order) by using carrier-based ranging based on the carrier of the RF signal 130. Like DGNSS, RTK positioning can use highly accurate GNSS receivers to make measurements of the RF signal 130 from known positions using the reference station 120. However, unlike DGNSS, RTK correction data (also called "RTK service data") includes highly accurate carrier-based ranging. The RTK correction data can be related to the mobile device 110 via radio broadcast and / or data communication network 150. The mobile device 110 can then use the RTK correction data to correct errors in its own carrier-based ranging using measurements of the RF signal 130 from its own GNSS receiver. Error corrections for RTK positioning can include corrections for satellite clocks and orbits, ionospheric and tropospheric delays, phase windup, solid earth tides, ocean loading, and / or site displacements including polar tides. This more accurate position fix (i.e., position) may be determined, for example, by the PPE executed by one or more processors of the mobile device 110. More specifically, in addition to the information provided to the SPE, the PPE may use RTK correction data to provide a high accuracy carrier-based position fix. Several GNSS techniques may be employed in the PPE, such as DGNSS, RTK, and PPP.

[0021] The mobile device 110 can determine its position using a position / position estimator or positioning engine (e.g., PPE) that incorporates ambiguity resolution and differential corrections. The position / position estimator may use estimation techniques such as by using an Extended Kalman Filter (EKF), Weighted Least Squares (WLS), Hatch filter, particle filter, etc. The accuracy of a position fix for the mobile device 110 may depend on its distance or "baseline" 160 from the reference station 120, the accuracy of the differential corrections, etc. While traditional DGNSS and RTK corrections are limited to a baseline 160 of the order of a few kilometers or tens of kilometers, new techniques may extend the baseline 160 to much longer distances using extension techniques for error correction. For example, Ultra-Long Baseline RTK (ULB-RTK) can use a multi-constellation, multi-frequency (MCMF) GNSS receiver in the mobile device 110 and tropospheric modeling to perform corrections for errors due to ionospheric and tropospheric delays, allowing for baselines 160 of up to 1000 km or more. Due to this increased distance, there may be fewer SVs 140 observable by both the mobile device 110 and the reference station 120. These SVs 140 are referred to herein as "common-view satellites."

[0022] DGNSS and RTK positioning can be further enhanced using network-based techniques. In network-based DGNSS / RTK, correction data from multiple reference stations 120 is sent to a service provider 170. The mobile device 110 can then receive DGNSS / RTK correction data on demand by sending a request to the service provider 170 including the approximate position of the mobile device 110 (e.g., based on a previously known position, a tracking area in a wireless communication network, or a non-GNSS-based positioning (such as a dead reckoning-based positioning of a vehicle), etc.). The service provider 170, which may comprise one or more computer servers, can then provide customized DGNSS / RTK service data to the mobile device 110 by interpolating the correction data from multiple reference stations 120 to provide DGNSS / RTK service data for the approximate position of the mobile device 110. To interpolate the correction data, the service provider 170 can execute sophisticated GNSS algorithms based on the geometry of the reference stations 120 used. Due to the sophistication of the interpolated solution, convergence times (the length of time it takes to obtain a high accuracy position fix) may be relatively long, and as previously noted, while this may not be an issue in applications where relatively long convergence times are tolerable (e.g., land surveying), it may be an issue in other applications where time and safety may be critical (e.g., autonomous driving).

[0023] The embodiments described herein below address these and other problems by providing an RTK / DGNSS system 100 in which single-reference-station-based DGNSS / RTK service data (also referred to herein as reference station correction data) from each of a plurality of reference stations 120 is provided to the mobile device 110. In some embodiments, such DGNSS / RTK service data based on or associated with a single reference station may be non-interpolated DGNSS / RTK service data. As described in more detail below, the selection of the reference station 120 may be made based on factors such as the approximate location of the mobile device, the geometry of the reference station 120, and / or other factors. Additionally, and as described in more detail below, the mobile device 110 may combine the correction data from the plurality of reference stations 120 in any of a variety of ways to determine a precise position fix for the mobile device 110. The selection of the reference station 120 may be made by one or more computer servers (e.g., service provider 170) communicatively coupled to the reference stations 120 and the mobile device 110 via a data communications network 150. As mentioned, the data communications network 150 may comprise any of a variety of public and / or private networks, which may include the Internet, one or more mobile carrier networks, and / or other such wide area networks (WANs).

[0024] As mentioned, based on the approximate position of the mobile device, two or more relevant reference stations 120 may be selected from which correction data may be provided to the mobile device 110. The number N of reference stations for which the server provides correction information may vary depending on the quality of service (QOS) or user requirements. N may additionally or alternatively be application specific, being larger when greater accuracy, availability, and / or reliability is required, taking into account other limitations (e.g., processing capabilities of the mobile device 110). Figures 2-5 show algorithms that may be used for such reference station selection.

[0025] 2 is an overhead view diagram 200 of the positions of four reference stations R1-R4 relative to an approximate mobile device position 210. As used herein, the notation "R" (e.g., R1-R4) may correspond to the position of a reference station (e.g., reference station 120 of RTK / DGNSS system 100 as shown in FIG. 1) and / or the reference station itself. Approximate mobile device position 210 may correspond to the location of a mobile device (e.g., mobile device 110) within a geographic region served by RTK / DGNSS system 100.

[0026] The reference station selection method illustrated in FIG. 2 is proximity-based. That is, reference stations may be selected based on their proximity to the approximate mobile device location 210. This may be determined using a radius 230, which may be used in a variety of ways, as illustrated. In some embodiments, for example, the reference station selection process may involve starting with a small radius 230 and increasing the size of the radius 230 until a desired number N of reference stations fall within an area 240 covered by the radius 230. Additional or alternative techniques may be used to determine the number N of reference stations that are closest to the approximate mobile device location 210. Alternatively, an embodiment may have a radius 230 of a predetermined length and may select all reference stations that fall within the area 240 defined by the predetermined radius 230. Once a reference station is selected, correction data from the reference station may be provided to the mobile device. In the example illustrated in FIG. 2, reference stations R1-R3 fall within the area 240 defined by the radius 230 and are therefore selected. Meanwhile, reference station R4 is not selected.

[0027] As an alternative to radius-based techniques, embodiments may reference stations based on geofencing or a predetermined area. For example, a geographic region served by the service provider 170 of the RTK / DGNSS system 100 may be divided into a number of predetermined areas, where each predetermined area has a corresponding set of predetermined reference stations serving the respective predetermined area. Thus, if the approximate mobile device position 210 falls within a predetermined area, the corresponding set of predetermined reference stations may be selected. An example of how this may be implemented is described below with respect to FIG. 5.

[0028] It may be noted that the density of reference stations may vary depending on the network capabilities. In some embodiments of the RTK / DGNSS system 100, the reference stations R1-R4 may be located only a few kilometers apart. In other embodiments, such as in the RTK / DGNSS system 100 implementing ULB-RTK, the reference stations may be hundreds of kilometers or more apart. The location and density of the reference stations may also vary based on the geographic region.

[0029] The approximate mobile device position 210 may be determined in any of a variety of ways depending on the desired functionality. In some embodiments, the approximate mobile device position 210 may be determined based on a previously determined GNSS-based position fix (e.g., GNSS, RTK, or DGNSS). In some embodiments, the approximate mobile device position 210 may be determined by the mobile device or a server using network-based positioning techniques that may use RF signals to perform multilateration and / or multiangulation of the mobile device to determine the mobile device position based on known positions of RF transceivers (e.g., Wi-Fi access points, cellular network-based stations, etc.).

[0030] FIG. 3 is a diagram 300 of four reference station positions R1-R4 and the approximate mobile device position 210, similar to FIG. 2. However, in this example, the reference station selection is not based solely on proximity to the approximate mobile device position 210. Instead, a "balanced" group of reference stations is selected such that the distance 320 is minimized between the center of gravity 330 of the polygon 340 formed by the approximate mobile device position 210 and the positions of the selected reference stations. If two reference stations are selected, the embodiment will minimize the distance between the midpoint of the line formed between the two reference stations and the approximate mobile device position 210. In some aspects, the "balanced" group may be selected with a fixed number N of reference stations, which may be selected or predetermined according to one or more of the aspects described above.

[0031] It may be noted that this balanced approach does not necessarily result in selecting the closest reference station. As shown in Figure 3, if reference station R5 is selected rather than reference station R2, the resulting centroid 360 of the polygon formed by R1, R5, R3, and R4 is actually farther away than the centroid 330 formed when R2 is used, even though R5 is closer to the approximate mobile device location 210 than R2. Selecting R2 rather than R5 shifts the centroid in the direction indicated by the dashed arrow.

[0032] This balanced approach can be beneficial in various scenarios. For example, a mobile device may be surrounded by buildings or geographic features that block some portions of the sky. A reference station may be similarly surrounded by such buildings or geographic features. Thus, even nearby reference stations may not be able to provide sufficient correction data for satellites that are visible by the mobile device. However, by making a balanced selection of reference stations on different opposing sides of the approximate mobile device position 210, embodiments can help increase the number of common view satellites between the mobile device and the selected reference station.

[0033] By similar reasoning, this balanced selection of reference stations may be beneficial in RTK / DGNSS systems with a distributed network of reference stations, where the reference stations are hundreds or thousands of kilometers apart. In such systems, the mobile device may not have many common-view satellites with any given reference station. However, by receiving a balanced group of reference stations, the embodiments may help to increase the number of common-view satellites between the mobile device and the selected reference station. In general, increasing the number of common-view satellites results in increased accuracy of each position determination. In a particular example, having a set of three or more satellites visible to both the mobile device and at least one of the multiple reference stations may help to ensure error corrections for at least the minimum number of satellites used for position determination. That said, the embodiments may be used even when fewer (or no) common-view satellites are available. With respect to common-view satellites, another technique for reference station selection may be used, as shown in FIG. 4.

[0034] 4 is a skyplot 400 that diagrammatically illustrates the azimuths and altitudes of various SVs 140 that are visible (observable) by reference stations R1 and R2. It may be noted that only a portion of the SVs are labeled to avoid clutter. As shown, the SVs 140 may be characterized as line-of-sight by reference station R1, line-of-sight by reference station R2, or line-of-sight by reference stations R1 and R2.

[0035] According to some embodiments, the reference station selection may be performed to maximize common view satellites between the selected reference station and the mobile device. Depending on the desired functionality, the reference station selection may be based on information received from the mobile device and / or the reference station regarding visible SVs 140. Using the RTK / DGNSS system 100 of FIG. 1 as an example, the mobile device 110 may send a request for RTK / DGNSS correction data to the service provider 170 for position fixes. The request may include or be accompanied by information regarding visible SVs 140 at the mobile device 110 (e.g., based on correction data acquired by a GNSS receiver of the mobile device 110). The service provider 170 may then select a reference station 120 based on the SV 140 line-of-sight at each of the reference stations 120, which may be provided to the service provider 170 by the reference station periodically (e.g., every 30 seconds, every minute, every 5 minutes, etc.), based on a triggering event (e.g., a determination of a change in line-of-sight SV 140), based on a request by the service provider 170, etc. Additionally or alternatively, the reference station selection may be based on the SV 140 line-of-sight at the mobile device and / or the reference station, as calculated based on the approximate location of the mobile device, the known locations of the reference stations, and the calculated or known current position of SV 140.

[0036] 4, where sky plot 400 shows SVs 140 that are line-of-sight to the mobile device, reference stations R1 and R2 may be selected based on the fact that at least one of the SVs 140 that are line-of-sight to the mobile device is also line-of-sight to reference stations R1 and R2. In some aspects, reference stations R1 and R2 may be selected based on the fact that all of the SVs 140 that are line-of-sight to the mobile device are also line-of-sight to reference stations R1, R2, or both.

[0037] In some embodiments, correction data from a reference station may be provided to a mobile device based on the mobile device's location within an area serviced by a mobile carrier network, an example of which is shown in FIG.

[0038] 5 is a diagram illustrating how data from various reference stations may be provided to various mobile devices 110 based on the mobile devices' respective locations within an area serviced by a mobile carrier network. While the example shown in FIG. 5 illustrates how reference station selection may be based on a beam 505 transmitted by a cellular base station 520, alternative embodiments may additionally or alternatively provide various reference station correction data based on other location-based criteria, such as serving cells, wireless heat maps (e.g., location based on detected transmitters and (optionally) transmit strength), etc.

[0039] The example shown in FIG. 5 illustrates a cellular base station 520 of a fifth generation new radio (5G NR) carrier network capable of transmitting RF signals in different directions using different beams 505. The cellular base station 520 in a 5G NR network is also referred to as a next generation node B or gNB. Using the beams, the base station 520 can communicate data specific to devices in an area served by a particular beam 505. According to an embodiment, this can enable the mobile network to provide reference station correction data specific to an area served by one or more beams 505 of one or more base stations 520. In FIG. 5, a first mobile device 110-1 is located in a first area 540-1 served by a first beam 505-1a of a first base station 520-1 and a first beam 505-2a of a second base station 520-2. Additionally, a second mobile device 110-2 located within a second area 540-2 is served by a second beam 505-1b of the first base station 520-1 and a second beam 505-2b of the second base station 520-2. According to some embodiments, the base station 520 may provide different reference station correction data on different beams via broadcast or specific transmission to one or more devices within the area 540 served by the beam 505. Thus, each of the beams 505-1a, 505-1b, 505-2a, and 505-2b used to transmit reference station correction data may transmit reference station correction data from a different set of one or more reference stations. For example, beam 505-1a may be used to transmit correction data from reference stations R1 and R2, beam 505-1b may be used to transmit correction data from reference stations R1, R3, and R4, beam 505-2a may be used to transmit correction data from reference station R5, and beam 505-2b may be used to transmit correction data from reference stations R1, R2, R4, and R5.In this manner, different areas 540 served by base station 520 may receive reference station correction data from different combinations of reference stations, where the combination of reference stations for a given area 540 is known to enable accurate RTK / DGNSS position determination for mobile device 110 within area 540. Alternative configurations may serve area 540 using different numbers of base stations 520, including a single base station or three or more base stations.

[0040] The determination of which reference station correction data to use for a particular beam 505 (or, more generally, a particular area 540 served by the mobile carrier network) may be made by a server at the base station, a location server in the network (e.g., a Location Management Function (LMF) in a 5G NR network), and / or other computer server communicatively coupled to the base station 520. The server may receive feedback from the mobile device 110, input from external sources (e.g., a network operator), data from reference stations, and / or similar inputs, and may employ machine learning and / or other algorithms to determine the validity of different reference station correction data in different areas 540 served by the mobile carrier network.

[0041] Once the reference stations 120 have been selected or identified (e.g., using one or more of the techniques previously described), the manner in which the corresponding reference correction data from these reference stations 120 is provided to the mobile device 110 may vary. This may depend on any of a variety of factors, including available bandwidth, performance requirements, desired functionality, and / or other factors. Figure 6 and the following description provide ways in which correction data from the reference stations 120 may be provided to the device 110, according to some embodiments.

[0042] FIG. 6 is a diagram of how various scheduling methods may be employed to provide reference station correction data to the mobile device 110 based on bandwidth or performance requirements, according to some embodiments. As with other figures herein, it will be understood that the examples provided in FIG. 6 are non-limiting. Embodiments may use additional or alternative scheduling methods depending on the desired functionality. Here, the correction data is represented by different blocks, where blocks R1, R2, and R3 represent correction data from the first, second, and third reference stations 120, respectively. Times are shown as T0, T1, T2, etc., and may represent the times at which a set of reference station correction data is transmitted. More precisely, these times may represent the times at which a server or cellular base station begins transmitting the reference station correction data to the mobile device 110. It should be noted that a set of reference station correction data may be transmitted by a single server or cellular base station, or a subset or the entire set of reference station correction data may be transmitted by two or more servers or cellular base stations. The subsets transmitted by different servers or cellular base stations may complement each other as described above with respect to FIG. 5. The subsets transmitted by different servers or cellular base stations may further overlap partially or completely to provide redundancy in scenarios where availability is important. Furthermore, the cellular base stations may be at least partially provided separately from the reference stations. In some aspects, some or all of the cellular base stations may be co-located with or provided by the respective reference stations.

[0043] The first scheduling method 600-1 utilizes the maximum bandwidth to provide reference station correction data from all reference stations (R1, R2, and R3) in every time interval (T0, T1, and T2). The second scheduling method 600-2 utilizes a slightly smaller bandwidth and provides reference station correction data from two reference stations (R1 and R2) per time interval and provides reference station correction data from a third reference station (R3) in every other time interval. The third scheduling method 600-3 utilizes even smaller bandwidth by switching between providing reference station correction data from two reference stations (R1 and R2) and from a third reference station (R3) in every other interval. Finally, the fourth scheduling method 600-4 utilizes the minimum rate and provides reference station correction data from a single reference station in each time interval, rotating from one reference station to the next in each time interval. As one skilled in the art will appreciate, different scheduling methods may be used for different numbers of reference stations to accommodate different bandwidth or performance requirements, etc.

[0044] In general, an increased amount of reference station correction data may result in higher performance. Thus, as the amount of data provided to the mobile device 110 decreases from method 600-1 to method 600-4, so may the corresponding performance. Method 600-4 may result in a less accurate position determination than method 600-1, for example. However, method 600-4 uses much less bandwidth than method 600-1. Thus, depending on the desired functionality, a scheduling method may be selected based on a desired (or required) balance between performance and available bandwidth.

[0045] As mentioned, the reference station correction data for a given reference station 120 may include highly accurate GNSS measurements of one or more satellites acquired by the reference station 120. The mobile device 110 may then use this information together with position information for the reference station 120 to perform DGNSS / RTK corrections of the GNSS measurements acquired by the mobile device 110 in the manner previously described, resulting in a highly accurate position determination for the mobile device 110. In some embodiments, the correction data may include position information for the reference station 120 and may be included in or take into account the correction data sent to the mobile device 110 (e.g., in the blocks shown in FIG. 6). Alternatively, the position information may be provided separately. According to some embodiments, the mobile device 110 may maintain a database or almanac of reference station position information that may be provided by the service provider 170. The manner in which the mobile device 110 may use the reference station correction data to improve the performance of the position determination may vary depending on the desired functionality.

[0046] According to the first option, for example, the mobile device 110 may estimate the spatial distribution of the DGNSS / RTK corrections using the geometry of the reference stations. In this way, the mobile device 110 can interpolate the DGNSS / RTK corrections at a given position, similar to the technique performed by the service provider 170 in conventional network-based DGNSS / RTK positioning. However, since the mobile device 110 can perform GNSS-based positioning to determine its position (with an accuracy of the order of several meters), it does not rely on the interpolation of the DGNSS / RTK corrections at a given position. The mobile device 110 can instead determine a more precise interpolation specific to its GNSS-based position. Thus, the resulting interpolated DGNSS / RTK corrections may be more precise and, ultimately, a corresponding high-precision position determination for the mobile device 110.

[0047] According to a second option, the mobile device 110 may execute multiple instances of a positioning engine. As previously mentioned, the mobile device 110 may comprise a position / position estimator, which may be implemented by one or more hardware and / or software components of the mobile device 110 (as described in more detail below). According to a second option, the position / position estimator may comprise multiple instances of a positioning engine (e.g., a PPE using estimation techniques such as EKF, WLS, Hatch filter, particle filter, etc.). For each of the multiple reference stations 120, the corresponding positioning engine may use the reference station correction data for the respective reference station to resolve a baseline between the UE and the respective reference station, resulting in multiple baseline solutions. The mobile device 110 may then calculate a position fix from the multiple baseline solutions.

[0048] Depending on the desired functionality, multiple baseline solutions may be combined in various ways. For example, according to some embodiments, baseline solutions may be combined simply by using an average, such as a simple average or a weighted average. According to some embodiments, baselines may be weighted according to baseline length (e.g., shorter baselines may be given a greater weight than longer baselines). Additionally or alternatively, baselines may also be weighted based on satellite geometry (e.g., baselines determined using multiple constellations with many satellites may be given a greater weight than baselines determined using a single constellation and / or fewer satellites). Alternative embodiments may employ additional or alternative techniques for combining baseline solutions.

[0049] According to a third option, the mobile device 110 may run a single positioning engine to process reference station correction data from multiple reference stations 120 to derive a single solution. That is, in contrast to the second option previously described, the positioning engine of the mobile device 110 may be capable of processing multiple inputs to derive a single positioning solution. For example, a centralized Kalman filter may be used to process all baselines and resolve ambiguities (e.g., relative to RTK) using reference station correction data from multiple reference stations 120. More specifically, according to some embodiments, the centralized Kalman filter may be used to estimate the mobile device's position (e.g., X, Y, and Z coordinates), receiver clock errors from each reference station, Inter-Satellite-Type Bias (ISTB), base station tropospheric zenith delay, and / or other ambiguities. As one skilled in the art will appreciate, such a centralized Kalman filter may be more difficult to implement than simply combining the outputs of multiple Kalman filters as described above with respect to the second option. However, this option may be advantageous from a performance standpoint (eg, accuracy, processing usage, etc.), subject to an upper limit.

[0050] It may be noted that the performance advantages of embodiments utilizing one or more of the above-described options for processing the reference station correction data may vary. A position determination for the mobile device 110 based on reference station correction data from multiple reference stations 120 may be more accurate and / or faster than a position determination based on reference station correction data from a single reference station 120 due to the constraints included in the multi-reference method. Additionally or alternatively, the utilization of reference station correction data from multiple reference stations 120 may provide an advantage in terms of availability. That is, if there is an outage at one reference station 120, the embodiment may continue to utilize reference station correction data from one or more additional reference stations 120 to perform a position determination for the mobile device 110.

[0051] This is equally applicable to sparse reference station networks. For example, in a sparse RTK / DGNSS system 100 with large inter-station distances (e.g., 1000 km or more), there may be only a relatively small number of SVs 140 that are common and visible to both the reference station 120 and the mobile device 110. However, there may be many more SVs 140 that are common and visible between the mobile device 110 and multiple reference stations 120 (e.g., as previously described with respect to FIG. 4). Thus, when reference station correction data is received by the mobile device 110 from multiple reference stations 120, the mobile device 110 may select RTK / DGNSS correction information for the common and visible SVs 140 from different reference stations 120. Thus, the amount of RTK / DGNSS correction information available to a mobile device 110 receiving reference station correction data from multiple reference stations 120 may be greater than the amount of available RTK / DGNSS correction information from any single reference station 120.

[0052] 7 is a simplified overhead view 700 diagram of a mobile device and multiple reference stations illustrating how multiple constraints on values ​​derived from base station correction data from multiple reference stations can be used to make a position determination for the mobile device, according to one embodiment. The various values ​​in FIG. 7 are as follows: POS U represents the (exact) position of the mobile device, and POS R1 represents the (exact) position of the first reference station, and POS R2 represents the (exact) position of the second reference station, and POS R3 represents the (exact) position of the third reference station.

[0053]

number

[0054] is the position vector from the first base station to the mobile device,

[0055]

number

[0056] is the position vector from the second reference station to the mobile device,

[0057]

number

[0058] is the position vector from the third reference station to the mobile device. As with other figures provided herein, Figure 7 is provided as a non-limiting illustrative example. Characteristics such as the number of reference stations and their relative positions to each other and to the mobile device may vary from situation to situation.

[0059] As noted, the values ​​shown in FIG. 7 may be derived from the known positions of the reference stations along with the reference station correction data from the reference stations. Constraints on these values ​​may be used to perform checks on the reliability and completeness of the reference station correction data. Moreover, these constraints may also be used to more quickly determine the mobile device position (POS). U ) may be determined. Some constraints may be expressed by the following equation:

[0060]

number

[0061] Equation (1) is a position vector consistency check that uses the known position of the base station and the vector from the base station to the mobile device. The position of the base station plus the vector to the mobile device should equal the position of the mobile device. This should be the same for all base stations. If the base station correction data for a base station does not match the base station correction data of other base stations, it may be ignored. More specifically,

[0062]

number

[0063] ,

[0064]

number

[0065] , and

[0066]

number

[0067] may represent the respective baseline solutions as described above. Based on the position vector consistency check, one or more baseline solutions may be removed from further processing based on deviating from the determined mobile device position, for example, by exceeding a threshold or exceeding other baseline solutions. Additionally or alternatively, voting logic or de-weighting as described below may be applied.

[0068] Equation (2) is a position vector constraint resulting from the relative relationship between the positions of the mobile device, the first reference station, and the second reference station. As shown in FIG. 8, the position vector between the first and second reference stations (which can be derived from the known positions of the first and second reference stations)

[0069]

number

[0070] is the position vector from the first base station to the mobile device

[0071]

number

[0072] Position vector from the mobile device to the second reference station

[0073]

number

[0074] plus (ii) the first base station. As will be appreciated, similar constraints may be derived from the relationships between (i) the mobile device, the second base station, and the third base station, and (ii) the mobile device, the third base station, and the first base station. Again, data from one base station may be ignored if it does not match data from the other base station. Removal of data from one or even both base stations from further processing again may affect the determined mobile device position (POS). U ) and / or how different the left and right sides of equation (2) are, for example, by comparing the norm of the difference to a maximum allowable deviation. Additionally or alternatively, unweighting as described below may be used.

[0075] Equation (3) is a carrier phase ambiguity check that can be used in RTK implementations. Similar to equation (2), the method also checks the carrier phase ambiguity (Δ∇Amb 12 ) is the carrier phase ambiguity (Δ∇Amb 1U ) from the mobile device to the second reference station, the carrier phase ambiguity (Δ∇Amb U2) plus. Again, similar constraints may be derived using baselines between (i) the mobile device, the second reference station, and the third reference station, and (ii) the mobile device, the third reference station, and the first reference station. Again, data from one reference station may be ignored if it does not match data from the other reference station. Corresponding criteria for removing data from one or both reference stations from further processing may be applied based on carrier phase ambiguities. Additionally or alternatively, unweighting as described below may be applied.

[0076] Equation (1), equation (2), and / or equation (3) may be used as a data integrity check to determine if the reference station correction data is good. As noted, the reference station correction data from a reference station may be ignored if it fails any or all of these checks. Voting logic using three or more reference stations may be used, for example, to identify and ignore information from incompatible reference stations.

[0077] Additionally or alternatively, such as when reference station data from only two reference stations is available, Equation (1), Equation (2), and / or Equation (3) may be used to determine whether a position determination based on the reference station correction data is good. For example, if an error is detected using Equation (1), Equation (2), and / or Equation (3), the position determination may be determined to be unreliable, and the position determination may then be ignored or de-weighted accordingly.

[0078] FIG. 9A is a flow diagram of a method 900-A for providing reference station correction data to a mobile device for RTK or DGNSS corrections, according to one embodiment. The method 900-A can utilize techniques described above and thus can be viewed as one implementation of previously described processes, including those illustrated in FIGS. 2-5. Alternative embodiments may vary in functionality by combining, separating, or otherwise modifying the functionality described in the blocks illustrated in FIG. 9A. Means for performing the functionality of one or more of the blocks illustrated in FIG. 9A may comprise hardware and / or software components of a computer system, such as the components illustrated in FIG. 12 and described herein below. The computer system may comprise a computer server corresponding to the service provider 170 illustrated in FIG. 1 and described above in this embodiment.

[0079] At block 910, the functionality comprises receiving information indicative of an approximate location of the mobile device or information regarding satellite vehicles line-of-sight to the mobile device. As noted in the embodiments described above, the approximate location of the mobile device may be determined in any of a variety of ways, such as a previously determined GNSS-based position fix (e.g., GNSS, RTK, or DGNSS), a sensor-based positioning (e.g., dead reckoning, image-based positioning, etc.), and / or a network-based positioning technique (which may perform multilateration and / or multiangulation of the mobile device using RF signals to determine the mobile device location based on the known position of the RF transceiver). The network-based positioning technique may include, for example, multi-round trip time (RTT), observed time difference of arrival (OTDOA) or downlink time difference of arrival (DL-TDOA), angle of arrival (AOA), angle of departure (AOD), and / or other positioning procedures that may be performed, for example, in a cellular or wireless local area network (WLAN). The information regarding satellite vehicles line-of-sight may be obtained by the mobile device itself. The approximate location of the mobile device, or information regarding satellite vehicles visible to the mobile device, may be provided by the mobile device itself (e.g., via a data communications network 150, such as a cellular network and / or the Internet) or by another entity. In some embodiments, for example, the mobile network may be able to provide the approximate location of the mobile device.

[0080] The means for performing the functionality in block 910 may include one or more software and / or hardware components of computer system 1200, such as bus 1205, processing unit 1210, communication subsystem 1230, working memory 1235, and / or other software and / or hardware components of computer system 1200 as shown in FIG. 12 and described in more detail below.

[0081] At block 920, the functionality comprises selecting a number of reference stations from which to obtain reference station correction data, the selecting being based at least in part on the approximate location of the mobile device. As previously described with reference to Figures 2-5, the reference stations may be selected using different techniques. For example, the reference stations may be selected to maximize the number of common-view GNSS satellites between the mobile device and the multiple reference stations. This "balanced" approach may be useful, especially when the distance between the reference stations is large (e.g., hundreds of kilometers or more) and different reference stations may have different common-view satellites with the mobile device. According to some embodiments, to maximize the number of common-view GNSS satellites between the mobile device and the multiple reference stations, the method may further comprise obtaining information from each of the multiple reference stations of the GNSS satellites that are visible by the respective reference station, or obtaining information from the mobile device indicative of the GNSS satellites that are visible by the mobile device, or both.

[0082] According to some embodiments, selecting the multiple reference stations may additionally or alternatively be based on a respective position of each of the multiple reference stations. In such embodiments, selecting the multiple reference stations may be based on a proximity of a respective position of each of the multiple reference stations to an approximate location of the mobile device. For example, the radius-based selection shown in FIG. 2 is a form of this type of reference station selection. In some embodiments, the reference station may be selected to minimize the distance between a midpoint or centroid of the reference station positions and the approximate location of the mobile device. For example, the process shown in FIG. 3 is a form of this type of reference station selection.

[0083] The means for performing the functionality in block 920 may include one or more software and / or hardware components of computer system 1200, such as bus 1205, processing unit 1210, working memory 1235, and / or other software and / or hardware components of computer system 1200 as shown in FIG. 12 and described in more detail below.

[0084] At block 930, the functionality comprises obtaining reference station correction data from each of the multiple reference stations, where for each reference station, the reference station correction data comprises data based on one or more measurements of RF signals from one or more GNSS satellites acquired by a GNSS receiver at the respective reference station. As one skilled in the art will appreciate, this reference station correction data may be used by the mobile device to perform RTK or DGNSS corrections to measurements of the GNSS satellites acquired by the mobile device. As mentioned, the correction data may include correction information based on the measurement data and the known position of the respective reference station. Additionally or alternatively, the correction data may include the measurement data itself, and (optionally) position information for the respective reference station. To enable the mobile device to determine its position, the reference station correction data for a given reference station may include or be associated with timing information regarding when one or more measurements of RF signals from one or more GNSS satellites were acquired by the reference station, position information regarding the position of the reference station, etc.

[0085] The means for performing the functionality in block 930 may include one or more software and / or hardware components of computer system 1200, such as bus 1205, processing unit 1210, communication subsystem 1230, working memory 1235, and / or other software and / or hardware components of computer system 1200 as shown in FIG. 12 and described in more detail below.

[0086] At block 940, the functionality comprises sending the reference station correction data to the mobile device. As previously mentioned, a computer server (e.g., service provider 170) may be communicatively coupled to the mobile device 110 via a data communications network 150. The data communications network 150 may comprise any of a variety of public and / or private networks, including the Internet, a mobile communications network, and the like. Thus, in some embodiments, sending the reference station correction data to the mobile device may comprise transmitting the reference station correction data from one or more mobile network base stations. As previously described with reference to FIG. 5, different selections of reference stations may be made for different mobile devices in different locations within different coverage areas (e.g., area 540) of one or more mobile network base stations. Thus, according to some embodiments where the approximate location of the mobile device is within a first coverage area of ​​one or more mobile network base stations, the method 900-A may further comprise sending correction data from a different plurality of reference stations to a second mobile device in a second coverage area of ​​the one or more mobile network base stations.

[0087] The means for performing the functionality in block 940 may include one or more software and / or hardware components of computer system 1200, such as bus 1205, processing unit 1210, communication subsystem 1230, working memory 1235, and / or other software and / or hardware components of computer system 1200 as shown in FIG. 12 and described in more detail below.

[0088] FIG. 9B is a flow diagram of a method 900-B for providing reference station correction data to a mobile device for RTK or DGNSS corrections according to another embodiment. The functionality in the blocks of FIG. 9B is similar to the corresponding blocks in FIG. 9A. However, in FIG. 9B, the functionality of block 925 explicitly refers to the selected reference station as a "subset of available reference stations from which reference station correction data should be obtained," which subset is referenced later in block 935. As with method 900-A of FIG. 9A, techniques described above can be utilized. In particular, the selection of the subset may include one or more of the processes illustrated in FIGS. 2-5 and described above. Alternative embodiments may vary in functionality by combining, separating, or otherwise modifying the functionality described in the blocks illustrated in FIG. 9B. Means for performing the functionality of one or more of the blocks illustrated in FIG. 9B may comprise hardware and / or software components of a computer system, such as the components illustrated in FIG. 12 and described herein below. The computer system may comprise a computer server corresponding to the service provider 170 illustrated in FIG. 1 and described above in this embodiment.

[0089] FIG. 10A is a flow diagram of a method 1000-A of applying RTK or DGNSS corrections in a mobile device, according to one embodiment. Method 1000-A may utilize techniques described above and may therefore be viewed as one implementation of previously described processes, including those described with reference to FIGS. 2-7. Alternative embodiments may vary in functionality by combining, separating, or otherwise modifying the functionality described in the blocks shown in FIG. 10A. Means for performing the functionality of one or more of the blocks shown in FIG. 10A may comprise hardware and / or software components of a mobile device, such as the components shown in FIG. 11 and described herein below.

[0090] In block 1005, the functionality optionally comprises sending a request for reference station correction data to a server and / or one or more mobile network base stations. As previously mentioned, a mobile device can send a request to a DGNSS / RTK service provider for DGNSS / RTK correction data. The request may include an approximate position of the mobile device (e.g., based on a previously known position, a non-GNSS-based positioning, etc.) and may also include an indication of the mobile device's ability to interpolate correction data. According to some embodiments, the request may additionally or alternatively comprise a QOS indicator and / or a requested number N of reference stations. The means for performing the functionality in block 1005 may include one or more software and / or hardware components of a computer system 1100, such as a bus 1105, a processing unit 1110, a wireless communication interface 1130, a memory 1160, and / or other software and / or hardware components of a mobile device 110 as shown in FIG. 11 and described in more detail below.

[0091] At block 1010, the functionality comprises obtaining, at the mobile device, reference station correction data from each of the multiple reference stations, where for each reference station, the reference station correction data comprises data based on one or more measurements of RF signals from one or more GNSS satellites, acquired by a GNSS receiver at the respective reference station. The reference station correction data from each of the multiple reference stations is limited to correction data associated with or acquired at the respective reference station. According to embodiments of the present disclosure, the reference station correction data does not include reference station correction data of any other reference station of the multiple reference stations. As noted, the correction data may include correction information based on the measurement data and the known position of the respective reference station. Additionally or alternatively, the correction data may include the measurement data itself, and (optionally) location information for the respective reference station. As previously described, the reference station correction data may be obtained from a computer server and / or one or more mobile network base stations. According to some embodiments, obtaining the reference station correction data from the computer server may comprise initiating a communication session between the mobile device and the computer server.

[0092] The means for performing the functionality in block 1010 may include one or more software and / or hardware components of a computer system 1100, such as the bus 1105, the processing unit 1110, the wireless communication interface 1130, the memory 1160, and / or other software and / or hardware components of the mobile device 110 as shown in FIG. 11 and described in more detail below.

[0093] At block 1020, the functionality comprises acquiring mobile device measurement data, the mobile device measurement data comprising one or more measurements acquired by a GNSS receiver at the mobile device of RF signals from one or more GNSS satellites. As one skilled in the art will appreciate, the mobile device can use the reference station correction data acquired at block 1010 to perform RTK or DGNSS corrections on the mobile device measurement data to enable the mobile device to make high accuracy position determinations.

[0094] The means for performing the functionality in block 1020 may include one or more software and / or hardware components of a computer system 1100, such as the bus 1105, the processing unit 1110, the GNSS receiver 1180, the memory 1160, and / or other software and / or hardware components of the mobile device 110 as shown in FIG. 11 and described in more detail below.

[0095] At block 1030, the functionality comprises determining a position of the mobile device based on the reference station correction data from each of the multiple reference stations and the mobile device measurement data. As previously described, the mobile device can use the reference station correction data without the need for interpolated RTK / DGNSS correction information as used in conventional RTK / DGNSS systems. The position determination can instead be performed, for example, by combining position determinations made from the reference station correction data of different reference stations or by using a single Kalman filter to process the reference station correction data from the multiple reference stations. Thus, according to some embodiments of method 1000-A, determining the position of the mobile device at block 1030 may comprise, for each of the multiple reference stations, determining an estimated position of the mobile device based on the reference station correction data from the respective reference station and the mobile device measurement data, and combining all of the estimated positions to determine the position of the mobile device. Moreover, according to some embodiments, combining all of the estimated positions may comprise taking a simple average or a weighted average of the estimated positions. Alternatively, according to some embodiments, determining the position of the mobile device comprises using a single Kalman filter to process reference station correction data from all reference stations of the multiple reference stations.

[0096] The means for performing the functionality in block 1030 may include one or more software and / or hardware components of a computer system 1100, such as the bus 1105, the processing unit 1110, the memory 1160, and / or other software and / or hardware components of the mobile device 110 as shown in FIG. 11 and described in more detail below.

[0097] As previously described with respect to equations (1)-(3), checks may be performed on the estimated mobile device position and / or other values ​​determined from the reference station correction data to determine whether the reference station correction data and / or estimated mobile device position are accurate. Thus, some embodiments of method 1000-A may further comprise verifying the accuracy of the determined position of the mobile device using carrier phase integer ambiguities or position vectors from at least two of the multiple reference stations.

[0098] Some embodiments may include additional or alternative features as described herein. For example, some embodiments of method 1000-A may include disregarding reference station correction data from one or more reference stations of the plurality of reference stations based on verification of the accuracy of the determined position of the mobile device, and determining an improved position of the mobile device based on the remaining reference station correction data from the plurality of reference stations and the mobile device measurement data.

[0099] Additionally or alternatively, as noted, method 1000-A may comprise sending a request for reference station correction data to a provider service. According to some embodiments, the request includes information indicative of an approximate location of the mobile device. Additionally or alternatively, the request includes at least one of a quality of service (QOS) or a number of reference stations to be included in the plurality of reference stations.

[0100] According to some embodiments, the method 1000-A may further comprise obtaining reference station correction data from each reference station of the plurality of reference stations comprises receiving the reference station correction data from one or more mobile network base stations. Receiving the reference station correction data from the one or more mobile network base stations may further comprise repeatedly receiving the reference station correction data from the one or more mobile network base stations. According to some embodiments, the repetition rate of receiving the reference station correction data may be based on at least one of a bandwidth of wireless communication with the one or more mobile network base stations or a performance requirement for determining the location of the mobile device.

[0101] FIG. 10B is a flow diagram of a method 1000-B of applying RTK or DGNSS corrections at a mobile device according to another embodiment. Similar to the method 1000-A of FIG. 10A, the method 1000-B can utilize the techniques described above and thus can be viewed as one implementation of the processes previously described, including the processes described with reference to FIGS. 6-7. Furthermore, the functionality in the blocks of FIG. 10B is similar to the corresponding blocks in FIG. 10A. The main difference in FIG. 10B is the functionality in block 1007, including the explicit selection of a subset of available reference stations from which to obtain reference station correction data, which may be performed by the mobile device itself. That is, according to some embodiments, the base station positions and (optionally) other information for base station selection (e.g., using the selection techniques shown in FIGS. 2-5 and described above) can be provided to the mobile device, enabling the mobile device to perform the base station selection. Information for reference station selection may be obtained by the mobile device, for example, via a broadcast and / or data communication network 150 (e.g., the Internet and / or another data network). The functionality of blocks 1015 and 1035 in FIG. 10B mimics the functionality of respective blocks 1010 and 1030 in FIG. 10A, except that blocks 1015 and 1035, as in FIG. 9B, explicitly refer to the selected reference station as a "subset of available reference stations from which reference station correction data should be obtained." Alternative embodiments may vary in functionality by combining, separating, or otherwise modifying the functionality described in the blocks shown in FIG. 10B. Means for performing the functionality of one or more of the blocks shown in FIG. 10B may comprise hardware and / or software components of a mobile device, such as the components shown in FIG. 11 and described herein below.

[0102] FIG. 10C is a flow diagram of a method 1000-C of applying RTK or DGNSS corrections at a mobile device according to another embodiment. Method 1000-C comprises a further variation of methods 1000-A and 1000-B of FIG. 10A and FIG. 10B. Here, the functionality at block 1010 may be the same as corresponding block 1010 of FIG. 10A, and comprises acquiring at the mobile device reference station correction data from each of a plurality of reference stations, where for each reference station, the reference station correction data comprises data based on one or more measurements of RF signals from one or more GNSS satellites acquired by a GNSS receiver at the respective reference station. The functionality at block 1017 comprises selecting a subset of the plurality of reference stations from which to use the acquired reference station correction data, where the subset comprises a plurality of reference stations, and where the selecting is based at least in part on the approximate location of the mobile device or on information about satellite vehicles visible to the mobile device. That is, in contrast to the functionality in block 1007 of method 1000-B, where the reference station from which to obtain reference station correction data is selected, the functionality in block 1017 comprises a posteriori selection of the reference station from which correction data is obtained. For example, this may be the case in an implementation in which the mobile device obtains correction data via broadcast. Again, this selection may use one or more of the selection techniques shown in Figures 2-5 and described above. Method 1000-C may then proceed similarly to method 1000-B, where measurement data is obtained (at block 1020) and the location of the mobile device is determined (at block 1035) based on the measurement data and the reference station correction data from each reference station of the subset. Alternative embodiments may vary in functionality by combining, separating, or otherwise modifying the functionality described in the blocks shown in Figure 10C. Means for performing the functionality of one or more of the blocks shown in Figure 10C may comprise hardware and / or software components of the mobile device, such as the components shown in Figure 11 and described herein below.

[0103] FIG. 11 is a block diagram of various hardware and software components of a mobile device 110, according to one embodiment. These components may be utilized as described herein above (e.g., in connection with FIGS. 1-10). For example, the mobile device 110 may perform one or more of the operations of the methods illustrated in FIGS. 10A-10C and / or the functions of the mobile device 110 as described in the embodiments herein. It should be noted that FIG. 11 is intended to provide only a generalized illustration of the various components, and any or all of the components may be utilized as appropriate. As previously noted, the mobile device 110 may vary in form and function and may ultimately comprise any GNSS-enabled device, including vehicles, commercial and consumer electronic devices, surveying equipment, and the like. Thus, in some instances, the components illustrated by FIG. 11 may be localized in a single physical device and / or distributed among various networked devices that may be disposed in different physical locations (e.g., different locations of a vehicle). It may further be noted that the reference stations may utilize similar hardware and / or software components as the mobile device 110 and / or computer system 1200 (described below) to provide the functionality described herein.

[0104] A mobile device 110 is illustrated comprising hardware elements that may be electrically coupled (or in other manner in communication, as appropriate) via a bus 1105. The hardware elements may include a processing unit 1110, which may include, but is not limited to, one or more general-purpose processors, one or more special-purpose processors (such as digital signal processing (DSP) chips, graphics processing units (GPUs), application specific integrated circuits (ASICs), etc.), and / or other processors, processing structures, or processing means. As shown in FIG. 11, some embodiments may have a separate digital signal processor (DSP) 1120 depending on the desired functionality. Position determination and / or other determinations based on wireless communication may be performed in the processing unit 1110 and / or in a wireless communication interface 1130 (described below). The mobile device 110 may also include one or more input devices 1170, which may include, but are not limited to, a keyboard, a touch screen, a touch pad, a microphone, buttons, dials, switches, etc., and one or more output devices 1115, which may include, but are not limited to, a display, a light emitting diode (LED), a speaker, etc. As will be appreciated, the types of input devices 1170 and output devices 1115 may depend on the type of mobile device 110 with which the input devices 1170 and output devices 1115 are integrated.

[0105] The mobile device 110 may also include a wireless communication interface 1130, which may comprise, but is not limited to, a modem, a network card, an infrared communication device, a wireless communication device, and / or a chipset (such as a Bluetooth® device, an IEEE 802.11 device, an IEEE 802.15.4 device, a Wi-Fi device, a WiMAX™ device, a wide area network (WAN) device, and / or various cellular devices), etc., which may enable the mobile device 110 to communicate over a network and / or directly with other devices as described herein. The wireless communication interface 1130 may enable data and signaling to be communicated (e.g., transmitted and received) with a network, for example, via a WAN access point, a cellular base station and / or other access node type, and / or other network components, computer systems, and / or any other electronic devices described herein. Communication may be performed via one or more wireless communication antennas 1132 that send and / or receive wireless signals 1134. The antenna 1132 may comprise one or more individual antennas, one or more antenna arrays, or any combination.

[0106] Depending on the desired functionality, the wireless communication interface 1130 may comprise a separate transceiver, a separate receiver and transmitter, or any combination of transceivers, transmitters, and / or receivers for communicating with base stations and other terrestrial transceivers such as wireless devices and access points. The mobile device 110 may communicate with different data networks, which may comprise a variety of network types. For example, a wireless wide area network (WWAN) may be a code division multiple access (CDMA) network, a time division multiple access (TDMA) network, a frequency division multiple access (FDMA) network, an orthogonal frequency division multiple access (OFDMA) network, a single carrier frequency division multiple access (SC-FDMA) network, a WiMAX™ (IEEE 802.16) network, etc. The CDMA network may implement one or more radio access technologies (RATs), such as CDMA2000™, Wideband CDMA (WCDMA™), etc. CDMA2000® includes IS-95, IS-2000, and / or IS-856 standards. A TDMA network may implement Global System for Mobile Communications (GSM), Digital Advanced Mobile Phone System (D-AMPS), or some other RAT. An OFDMA network may employ Long Term Evolution (LTE), LTE Advanced, 5G NR, 6G, etc. 5G NR, LTE, LTE Advanced, GSM, and WCDMA® are described in documents from the 3rd Generation Partnership Project (3GPP®). CDMA2000® is described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP® 2). 3GPP® documents and 3GPP® 2 documents are publicly available. A wireless local area network (WLAN) may also be an IEEE 802.11x network, and a wireless personal area network (WPAN) may be a Bluetooth network, an IEEE 802.15x, or some other type of network.The techniques described herein may also be used for any combination of WWAN, WLAN, and / or WPAN.

[0107] The mobile device 110 may further include sensors 1140. The sensors 1140 may comprise, without limitation, one or more inertial sensors and / or other sensors (e.g., accelerometers, gyroscopes, cameras, magnetometers, altimeters, microphones, proximity sensors, light sensors, barometers, etc.), some of which may be used in some cases to supplement and / or facilitate the position determinations described herein.

[0108] An embodiment of the mobile device 110 may also include a GNSS receiver 1180 capable of receiving signals 1184 from one or more GNSS satellites (e.g., SV 140) as described herein using an antenna 1182 (which may be the same as antenna 1132). The GNSS receiver 1180 can use conventional techniques to extract a position of the mobile device 110 from a GNSS SV (e.g., SV 140 of FIG. 3 ) of a GNSS system, such as GPS, GAL, Global Navigation Satellite System (GLONASS), Quasi-Zenith Satellite System (QZSS) over Japan, Indian Regional Navigation Satellite System (IRNSS) over India, and Beidou Navigation Satellite System (BDS) over China. Moreover, the GNSS receiver 1180 may be used in conjunction with various augmentation systems (e.g., Satellite-Based Augmentation Systems (SBAS)), which may be associated with or otherwise enabled for use with one or more global and / or regional navigation satellite systems, such as, for example, Wide Area Augmentation System (WAAS), European Geostationary Navigation Overlay Service (EGNOS), Multifunction Satellite Augmentation System (MSAS), and Geo-Augmented Navigation System (GAGAN).

[0109] It may be noted that although the GNSS receiver 1180 shown in FIG. 11 is shown as a separate component from other components in the mobile device 110, the embodiment is not so limited. As used herein, the term "GNSS receiver" may comprise hardware and / or software components configured to obtain GNSS measurements (measurements from GNSS satellites). Thus, in some embodiments, the GNSS receiver may comprise a measurement engine executed (as software) by one or more processing units, such as the processing unit 1110, the DSP 1120, and / or a processing unit (e.g., in a modem) in the wireless communication interface 1130. The GNSS receiver may also optionally include a positioning engine, such as those described herein (e.g., EKF / Kalman filter, WLS, Hatch filter, particle filter, etc.), that can use the GNSS measurements from the measurement engine and RTK / D GNSS correction information to determine the position of the GNSS receiver. The positioning engine may also be executed by one or more processing units, such as the processing unit 1110 and / or the DSP 1120.

[0110] The mobile device 110 may further include and / or be in communication with a memory 1160. The memory 1160 may comprise a machine-readable or computer-readable medium, which may include, but is not limited to, local and / or network-accessible storage, disk drives, drive arrays, optical storage devices, solid-state storage devices such as random access memory (RAM) and / or read-only memory (ROM) that may be programmable, flash-updateable, and the like. Such storage devices may be configured to implement any suitable data storage system, including, but not limited to, various file systems, database structures, and the like.

[0111] The memory 1160 of the mobile device 110 may also comprise software elements (not shown in FIG. 11 ) including other code, such as an operating system, device drivers, executable libraries, and / or one or more application programs, which may comprise computer programs provided by various embodiments and / or may be designed to implement methods and / or configure systems provided by other embodiments, as described herein. By way of example only, one or more procedures described with respect to the methods described above may be implemented as code and / or instructions in the memory 1160 executable by the mobile device 110 (and / or the processing unit 1110 or DSP 1120 within the mobile device 110). In one aspect, such code and / or instructions may then be used to configure and / or adapt a general-purpose computer (or other device) to perform one or more operations in accordance with the methods described.

[0112] FIG. 12 is a block diagram of an embodiment of a computer system 1200 that may be utilized and / or incorporated into a service provider 170, a reference station 120, a base station, a computer server, and / or other devices described herein. FIG. 12 provides a block diagram of an embodiment of a computer system 1200 that can perform methods provided by various other embodiments, such as those described with respect to FIGS. 1-9. It should be noted that FIG. 12 is only intended to provide a generalized illustration of the various components, any or all of which may be utilized as appropriate. Thus, FIG. 12 broadly illustrates how individual system elements may be implemented in a relatively separated or relatively more integrated manner. Additionally, similar to the components of FIG. 11, the components illustrated by FIG. 12 can be localized in a single device and / or distributed among various networked devices that may be located in different physical or geographic locations.

[0113] A computer system 1200 is illustrated comprising hardware elements that may be electrically coupled (or in other suitable communication) via a bus 1205. The hardware elements may include a processing unit 1210, which may include, but is not limited to, one or more general purpose processors, one or more special purpose processors (such as DSPs, ASICs, GPUs, etc.), and / or other processing structures that may be configured to perform one or more of the methods described herein, including those described with respect to Figures 9A and 9B. The computer system 1200 may also include one or more input devices 1215, which may include, but is not limited to, a mouse, keyboard, camera, microphone, etc., and one or more output devices 1220, which may include, but is not limited to, a display device, printer, etc. The types of input devices 1215 and output devices 1220 may depend on the type of computer system 1200 with which the input devices 1215 and output devices 1220 are integrated.

[0114] Computer system 1200 may further include (and / or be in communication with) one or more non-transitory storage devices 1225, which may comprise local and / or network-accessible storage, and / or may include solid-state storage devices, such as, but not limited to, disk drives, drive arrays, optical storage devices, RAM and / or ROM, which may be programmable, flash-updateable, etc. Such storage devices may be configured to implement any suitable data storage system, including, but not limited to, various file systems, database structures, etc.

[0115] The computer system 1200 may also include a communications subsystem 1230, which may include support for wireline and / or wireless communications technologies, managed and controlled (in some embodiments) by a wireless communications interface 1233. The communications subsystem 1230 may include a modem, a network card (wireless or wired), an infrared communications device, a wireless communications device, and / or a chipset, etc. The communications subsystem 1230 may include one or more input and / or output communications interfaces, such as the wireless communications interface 1233, to enable data and signaling to be exchanged with networks, mobile devices, other computer systems, and / or any other electronic devices described herein. In particular, if the computer system 1200 comprises a base station, the wireless communications interface 1233 may enable the base station to wirelessly communicate with one or more mobile devices 110.

[0116] In many embodiments, the computer system 1200 further comprises a working memory 1235, which may include a RAM device and / or a ROM device. The software elements shown as residing in the working memory 1235 may include other code, such as an operating system 1240, device drivers, executable libraries, and / or applications 1245, which may comprise computer programs provided by various embodiments and / or may be designed to implement methods and / or configure systems provided by other embodiments, as described herein. By way of example only, one or more procedures described with respect to the methods described above, such as the methods described with respect to Figures 9A and 9B, may be implemented as code and / or instructions stored (e.g., temporarily) in the working memory 1235 and executable by a computer (and / or a processing unit within the computer, such as processing unit 1210), and in one aspect, such code and / or instructions may then be used to configure and / or adapt a general-purpose computer (or other device) to perform one or more operations according to the methods described.

[0117] A set of these instructions and / or code may be stored on a non-transitory computer-readable storage medium, such as storage device 1225 described above. In some cases, the storage medium may be incorporated within a computer system, such as computer system 1200. In other embodiments, the storage medium may be separate from the computer system (e.g., a removable medium, such as an optical disk) and / or may be provided in an installation package, such that the storage medium may be used to program, configure, and / or adapt a general-purpose computer with the instructions / code stored thereon. These instructions may take the form of executable code executable by computer system 1200 and / or may take the form of source and / or installable code that, upon compilation and / or installation on computer system 1200 (e.g., using any of a variety of commonly available compilers, installation programs, compression / decompression utilities, etc.), then takes the form of executable code.

[0118] It will be apparent to those skilled in the art that substantial modifications may be made according to particular requirements. For example, customized hardware may be used and / or particular elements may be implemented in hardware, software (including portable software such as applets), or both. Furthermore, connection to other computing devices, such as network input / output devices, may be employed.

[0119] With reference to the accompanying figures, components that may include memory may include non-transitory machine-readable media. As used herein, the terms "machine-readable media" and "computer-readable media" refer to any storage medium that participates in providing data that causes a machine to operate in a specific manner. In the embodiments provided above, various machine-readable media may participate in providing instructions / code to a processing unit and / or other devices for execution. Additionally or alternatively, machine-readable media may be used to store and / or transport such instructions / code. In many implementations, the computer-readable media is a physical and / or tangible storage medium. Such media may take many forms, including, but not limited to, non-volatile media and volatile media. Common forms of computer-readable media include, for example, magnetic media and / or optical media, any other physical media with a pattern of holes, RAM, programmable ROM (PROM), erasable PROM (EPROM), FLASH-EPROM, any other memory chip or cartridge, a carrier wave as described below, or any other medium from which instructions and / or code can be read by a computer.

[0120] The methods, systems, and devices described herein are examples. Various embodiments may omit, substitute, or add various procedures or components as appropriate. For example, features described with respect to some embodiments may be combined in various other embodiments. Different aspects and elements of the embodiments may be combined in a similar manner. Various components of the diagrams provided herein may be embodied in hardware and / or software. Also, technology evolves, and thus many of the elements are examples that do not limit the scope of the disclosure to those specific examples.

[0121] It has proven convenient at times, primarily for reasons of common usage, to refer to such signals as bits, information, values, elements, symbols, characters, variables, terms, numbers, numeric values, or the like. It should be understood, however, that all of these or similar terms are to be associated with the appropriate physical quantities and are merely convenient labels. Unless otherwise indicated, and as is apparent from the above description, it will be appreciated that throughout this specification descriptions utilizing terms such as "processing," "calculating," "calculating," "determining," "ascertaining," "identifying," "associating," "measuring," "performing," and the like refer to the actions or processes of a particular apparatus, such as a special purpose computer or similar special purpose electronic computing device. Thus, in the context of this specification, a special purpose computer or similar special purpose electronic computing device or system is capable of manipulating or transforming signals that are commonly represented as physical electronic, electrical, or magnetic quantities in the memory, registers, or other information storage, transmission, or display devices of the special purpose computer or similar special purpose electronic computing device or system.

[0122] The terms "and" and "or" as used herein may include various meanings that are also expected to depend at least in part on the context in which such terms are used. Typically, "or" when used to link an enumeration such as A, B, or C is intended to mean A, B, and C, which are used herein in an inclusive sense, as well as A, B, or C, which are used herein in an exclusive sense. In addition, the term "one or more" as used herein may be used to describe any feature, structure, or characteristic in the singular or may be used to describe some combination of features, structures, or characteristics. However, it should be noted that this is merely an illustrative example, and claimed subject matter is not limited to this example. Furthermore, the term "at least one of," when used to link an enumeration such as A, B, or C, may be interpreted to mean any combination of A, B, and / or C, such as A, AB, AA, AAB, AABBCCC, etc.

[0123] Although several embodiments have been described, various modifications, alternative configurations, and equivalents may be used without departing from the scope of the present disclosure as defined by the appended claims. For example, the above elements may only be components of a larger system, and other rules may take precedence over or otherwise modify the application of the various embodiments. Also, some steps may be undertaken before, during, or after the above elements are considered. Thus, the above description does not limit the scope of the present disclosure.

[0124] In view of this description, embodiments may include various combinations of features. Example implementations are described in the following numbered clauses. Clause 1: A method for providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections, the method comprising the steps of receiving information indicating an approximate position of the mobile device or information regarding a satellite vehicle visible to the mobile device; selecting a plurality of reference stations from which to obtain reference station correction data, the selection being based at least in part on the approximate position of the mobile device or information regarding the satellite vehicle visible to the mobile device; obtaining reference station correction data from each of the plurality of reference stations, where for each reference station, the reference station correction data comprises data based on one or more measurements acquired by a GNSS receiver at the respective reference station; and sending the reference station correction data to the mobile device. Clause 2: The method of clause 1, wherein the step of selecting a plurality of reference stations is additionally based on a respective position of each reference station of the plurality of reference stations. Clause 3: The method of clause 1 or 2, wherein the step of selecting a plurality of base stations is based on a proximity of a respective position of each of the plurality of base stations to an approximate position of the mobile device. Clause 4: The method of clause 1 or 2, wherein the plurality of reference stations are selected to minimize a distance between a midpoint or centroid of the reference station positions and an approximate position of the mobile device. Clause 5: The method of clause 1, wherein the multiple reference stations are selected to maximize a number of common-view GNSS satellites between the mobile device and the multiple reference stations. Clause 6: The method of clause 5, wherein, in order to maximize the number of common view GNSS satellites between the mobile device and the plurality of reference stations, the method further comprises the step of obtaining, from each of the plurality of reference stations, information indicative of the GNSS satellites visible by the respective reference station, or obtaining, from the mobile device, information indicative of the GNSS satellites visible by the mobile device, or both. Clause 7: The method of any one of clauses 1 to 6, wherein the step of selecting a plurality of reference stations comprises the step of determining a number of reference stations to be included in the plurality of reference stations. Clause 8: The method of clause 7, wherein the number of reference stations is determined based on at least one of a quality of service (QOS), a user request from a mobile device, or an application of the mobile device. Clause 9: The method of any of clauses 1 to 8, wherein sending the reference station correction data to the mobile device comprises transmitting the reference station correction data from one or more mobile network base stations. Clause 10: The method of clause 9, wherein the approximate location of the mobile device is within a first coverage area of ​​one or more mobile network base stations, the method further comprising sending reference station correction data from a different plurality of reference stations to a second mobile device within a second coverage area of ​​the one or more mobile network base stations. Clause 11: A method for applying real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections on a mobile device, the method comprising the steps of acquiring at the mobile device reference station correction data from each of a plurality of reference stations, where for each reference station, the reference station correction data comprises one or more measurements acquired by a GNSS receiver at the respective reference station; acquiring mobile device measurement data, where the mobile device measurement data comprises one or more measurements acquired by the GNSS receiver at the mobile device; and determining a position of the mobile device based on the reference station correction data from each of the plurality of reference stations and the mobile device measurement data. Clause 12: The method of clause 11, wherein the step of determining a position of the mobile device comprises the steps of: determining, for each reference station of the plurality of reference stations, an estimated position of the mobile device based on reference station correction data from the respective reference station and the mobile device measurement data; and determining the position of the mobile device based on the estimated position. Clause 13: The method of clause 12, wherein determining a location of the mobile device based on the estimated locations comprises taking a simple or weighted average of at least some of the estimated locations. Clause 14: The method of clause 11, wherein determining a position of the mobile device comprises using a single Kalman filter to process reference station correction data from multiple reference stations. Clause 15: The method of any of clauses 11 to 14, further comprising verifying the accuracy of the determined position of the mobile device using carrier-phase integer ambiguities or position vectors from at least two of the plurality of reference stations. Clause 16: The method of clause 15, further comprising the steps of disregarding reference station correction data from one or more reference stations of the plurality of reference stations based on verification of the accuracy of the determined position of the mobile device, and determining an improved position of the mobile device based on the remaining reference station correction data from the plurality of reference stations and the mobile device measurement data. Clause 17: The method of any of clauses 11 to 16, further comprising the step of sending a request for reference station correction data to a provider service. Clause 18: The method of clause 17, wherein the request includes information indicating an approximate location of the mobile device. Clause 19: The method of clause 17 or 18, wherein the request includes at least one of a quality of service (QOS) or a number of reference stations to be included in the plurality of reference stations. Clause 20: The method of any of clauses 11 to 19, wherein obtaining reference station correction data from each reference station of the plurality of reference stations comprises receiving the reference station correction data from one or more mobile network base stations. Clause 21: The method of clause 20, wherein receiving the reference station correction data from the one or more mobile network base stations comprises repeatedly receiving the reference station correction data from the one or more mobile network base stations. Clause 22: The method of clause 21, wherein the repetition rate of receiving the reference station correction data is based on at least one of a bandwidth of wireless communication with one or more mobile network base stations, or a performance requirement for determining the position of the mobile device. Clause 23: A computer server for providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections, the computer server comprising: a transceiver, a memory, and one or more processing units communicatively coupled to the transceiver and the memory, the one or more processing units configured to: receive information indicative of an approximate position of the mobile device or information regarding a satellite vehicle visible to the mobile device; select a plurality of reference stations from which to obtain reference station correction data, the selecting being based at least in part on the approximate position of the mobile device or information regarding the satellite vehicle visible to the mobile device; obtain reference station correction data from each of the plurality of reference stations, where for each reference station, the reference station correction data comprises data based on one or more measurements acquired by a GNSS receiver at the respective reference station; and send the reference station correction data to the mobile device via the transceiver. Clause 24: The computer server of clause 23, wherein the one or more processing units are additionally configured to select a plurality of reference stations based on a respective position of each reference station of the plurality of reference stations. Clause 25: The computer server of clause 23 or 24, wherein the one or more processing units are additionally configured to select a plurality of base stations based on a proximity of a position of each of the plurality of base stations to an approximate position of the mobile device. Clause 26: The computer server of clause 23 or 24, wherein the one or more processing units are configured to select a number of reference stations so as to minimize a distance between a midpoint or centroid of the reference station positions and an approximate position of the mobile device. Clause 27: The computer server of clause 23, wherein the one or more processing units are configured to select the plurality of reference stations to maximize a number of common-view GNSS satellites between the mobile device and the plurality of reference stations. Clause 28: The computer server of clause 27, wherein, in order to maximize the number of common view GNSS satellites between the mobile device and the plurality of reference stations, the one or more processing units are configured to obtain, from each of the plurality of reference stations, information indicative of the GNSS satellites visible by the respective reference station, or obtain, from the mobile device, information indicative of the GNSS satellites visible by the mobile device, or both. Clause 29: The computer server of any of clauses 23 to 28, wherein, to select a plurality of reference stations, the one or more processing units are configured to determine a number of reference stations to be included in the plurality of reference stations. Clause 30: The computer server of clause 29, wherein the one or more processing units are configured to determine the number of reference stations based on at least one of a quality of service (QOS), a user request from a mobile device, or an application of the mobile device. Clause 31: A computer server according to any of clauses 23 to 30, wherein the one or more processing units are configured to transmit the reference station correction data from one or more mobile network base stations to send the reference station correction data to the mobile device. Clause 32: The computer server of any of clauses 23 to 31, wherein when the approximate location of the mobile device is within a first coverage area of ​​the one or more mobile network base stations, the one or more processing units are configured to send reference station correction data from a different plurality of reference stations to a second mobile device in a second coverage area of ​​the one or more mobile network base stations. Clause 33: A mobile device for applying real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections, the mobile device comprising a transceiver, a GNSS receiver, a memory, and one or more processing units communicatively coupled to the transceiver, the GNSS receiver, and the memory, the one or more processing units configured to: acquire reference station correction data from each reference station of a plurality of reference stations via the transceiver, where for each reference station, the reference station correction data comprises one or more measurements acquired by the GNSS receiver at the respective reference station; acquire mobile device measurement data, where the mobile device measurement data comprises one or more measurements acquired by the GNSS receiver of the mobile device; and determine a position of the mobile device based on the reference station correction data from each reference station of the plurality of reference stations and the mobile device measurement data. Clause 34: The mobile device of clause 33, wherein to determine a position of the mobile device, the one or more processing units are configured to: determine, for each reference station of the plurality of reference stations, an estimated position of the mobile device based on the reference station correction data from the respective reference station and the mobile device measurement data; and determine the position of the mobile device based on the estimated position. Clause 35: The mobile device of clause 34, wherein to determine a location of the mobile device based on the estimated locations, the one or more processing units are configured to take a simple or weighted average of at least some of the estimated locations. Clause 36: The mobile device of clause 33, wherein, to determine a position of the mobile device, the one or more processing units are configured to use a single Kalman filter to process reference station correction data from multiple reference stations. Clause 37: A mobile device of any of clauses 33 to 36, wherein the one or more processing units are further configured to verify an accuracy of the determined position of the mobile device using carrier-phase integer ambiguities or position vectors from at least two of the plurality of reference stations. Clause 38: The mobile device of clause 37, wherein the one or more processing units are further configured to ignore reference station correction data from one or more reference stations among the plurality of reference stations based on verification of an accuracy of the determined position of the mobile device, and determine an improved position of the mobile device based on the remaining reference station correction data from the plurality of reference stations and the mobile device measurement data. Clause 39: The mobile device of any of clauses 33 to 38, wherein the one or more processing units are further configured to transmit a request for reference station correction data to the provider service via the transceiver. Clause 40: The mobile device of clause 39, wherein the one or more processing units are further configured to include in the request information indicative of an approximate location of the mobile device. Clause 41: The mobile device of clause 39 or 40, wherein the one or more processing units are further configured to include in the request at least one of a quality of service (QOS) or a number of reference stations to be included in the plurality of reference stations. Clause 42: In a mobile device of any of clauses 33 to 41, in order to obtain reference station correction data from each reference station of the plurality of reference stations, the one or more processing units are configured to receive reference station correction data from one or more mobile network base stations. Clause 43: The mobile device of clause 42, wherein for receiving the reference station correction data from the one or more mobile network base stations, the one or more processing units are configured to repeatedly receive the reference station correction data from the one or more mobile network base stations. Clause 44: A mobile device according to clause 43, wherein the repetition rate of receiving reference station correction data is based on at least one of a bandwidth of wireless communication with one or more mobile network base stations, or a performance requirement for determining the position of the mobile device. Clause 45: A device for providing reference station correction data to a mobile device for real time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections, the device comprising: means for receiving information indicative of an approximate position of the mobile device or information regarding a satellite vehicle visible to the mobile device; means for selecting a plurality of reference stations from which to obtain reference station correction data, the selection being based at least in part on the approximate position of the mobile device or information regarding the satellite vehicle visible to the mobile device; means for obtaining reference station correction data from each of the plurality of reference stations, where for each reference station, the reference station correction data comprises data based on one or more measurements acquired by a GNSS receiver at the respective reference station; and means for sending the reference station correction data to the mobile device. Clause 46: The device of clause 45, wherein selecting the plurality of reference stations is additionally based on a respective position of each of the plurality of reference stations. Clause 47: The device of clause 45 or 46, wherein selecting the plurality of reference stations is based on a proximity of a respective position of each of the plurality of reference stations to an approximate position of the mobile device. Clause 48: The device of clause 45 or 46, wherein the means for selecting a plurality of base stations comprises means for selecting a plurality of base stations so as to minimize a distance between a midpoint or centroid of the base station positions and an approximate position of the mobile device. Clause 49: The device of clause 45, wherein the means for selecting a plurality of reference stations comprises means for selecting the plurality of reference stations so as to maximize a number of common view GNSS satellites between the mobile device and the plurality of reference stations. Clause 50: The device of clause 49, wherein, in order to maximize the number of common view GNSS satellites between the mobile device and the plurality of reference stations, the device further comprises means for obtaining, from each of the plurality of reference stations, information indicative of the GNSS satellites visible by the respective reference station, or means for obtaining, from the mobile device, information indicative of the GNSS satellites visible by the mobile device, or both. Clause 51: The device of any of clauses 45 to 50, wherein the means for selecting a plurality of reference stations comprises means for determining a number of reference stations included in the plurality of reference stations. Clause 52: The device of clause 51, wherein the number of reference stations is determined based on at least one of a Quality of Service (QOS), a user request from the mobile device, or an application of the mobile device. Clause 53: The device of any of clauses 45 to 52, wherein the means for sending the reference station correction data to the mobile device comprises means for transmitting the reference station correction data from one or more mobile network base stations. Clause 54: A device for applying real time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections on a mobile device, the device comprising: means for acquiring at the mobile device reference station correction data from each of a plurality of reference stations, where for each reference station, the reference station correction data comprises one or more measurements acquired by a GNSS receiver at the respective reference station; means for acquiring mobile device measurement data, where the mobile device measurement data comprises one or more measurements acquired by the GNSS receiver at the mobile device; and means for determining a position of the mobile device based on the reference station correction data from each of the plurality of reference stations and the mobile device measurement data. Clause 55: The device of clause 54, wherein the means for determining a position of the mobile device comprises: means for determining, for each reference station of the plurality of reference stations, an estimated position of the mobile device based on base station correction data from the respective reference station and the mobile device measurement data; and means for determining a position of the mobile device based on the estimated position. Clause 56: The device of clause 55, wherein the means for determining a position of the mobile device based on the estimated positions comprises means for taking a simple or weighted average of at least some of the estimated positions. Clause 57: The device of clause 54, wherein the means for determining a position of the mobile device comprises means for using a single Kalman filter to process the reference station correction data from a plurality of reference stations. Clause 58: The device of any of clauses 54 to 57, further comprising means for verifying the accuracy of the determined position of the mobile device using carrier-phase integer ambiguities or position vectors from at least two of the plurality of reference stations. Clause 59: The device of clause 58, further comprising means for disregarding reference station correction data from one or more of the plurality of reference stations based on verification of an accuracy of the determined position of the mobile device, and means for determining an improved position of the mobile device based on the remaining reference station correction data from the plurality of reference stations and the mobile device measurement data. Clause 60: The device of any of clauses 54 to 59, further comprising means for transmitting a request for reference station correction data to a provider service. Clause 61: The device of clause 60, further comprising means for including in the request information indicative of an approximate location of the mobile device. Clause 62: The device of clause 60 or 61, further comprising means for including in the request at least one of a quality of service (QOS) or a number of reference stations to be included in the plurality of reference stations. Clause 63: In the device of any of clauses 54 to 62, the means for obtaining reference station correction data from each reference station of the plurality of reference stations comprises means for receiving the reference station correction data from one or more mobile network base stations. Clause 64: The device of clause 63, wherein the means for receiving reference station correction data from the one or more mobile network base stations comprises means for repeatedly receiving the reference station correction data from the one or more mobile network base stations. Clause 65: A device as in clause 64, wherein the repetition rate of receiving reference station correction data is based on at least one of a bandwidth of wireless communication with one or more mobile network base stations, or a performance requirement for determining the position of the mobile device. Clause 66: A non-transitory computer-readable medium storing instructions for providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections, the instructions comprising code for receiving information indicative of an approximate position of the mobile device or information regarding a satellite vehicle visible to the mobile device; selecting a plurality of reference stations from which to obtain reference station correction data, the selecting being based at least in part on the approximate position of the mobile device or information regarding the satellite vehicle visible to the mobile device; obtaining reference station correction data from each of the plurality of reference stations, where for each reference station, the reference station correction data comprises data based on one or more measurements acquired by a GNSS receiver at the respective reference station; and sending the reference station correction data to the mobile device. Clause 67: The non-transitory computer-readable medium of clause 66, wherein selecting the plurality of reference stations is additionally based on a respective position of each reference station of the plurality of reference stations. Clause 68: The non-transitory computer-readable medium of clause 66 or 67, wherein selecting the plurality of base stations is based on a proximity of a respective location of each of the plurality of base stations to an approximate location of the mobile device. Clause 69: The non-transitory computer-readable medium of clause 66 or 67, wherein the code for selecting a plurality of base stations comprises code for selecting a plurality of base stations so as to minimize a distance between a midpoint or centroid of the base station positions and an approximate position of the mobile device. Clause 70: The non-transitory computer-readable medium of clause 66, wherein the code for selecting a plurality of reference stations comprises code for selecting a plurality of reference stations to maximize a number of common-view GNSS satellites between the mobile device and the plurality of reference stations. Clause 71: The non-transitory computer-readable medium of clause 70, wherein, to maximize a number of common view GNSS satellites between the mobile device and the plurality of reference stations, the instructions further comprise code for obtaining, from each of the plurality of reference stations, information indicative of GNSS satellites visible by the respective reference station, or obtaining, from the mobile device, information indicative of GNSS satellites visible by the mobile device, or both. Clause 72: The non-transitory computer-readable medium of any of clauses 66 to 71, wherein the code for selecting a plurality of reference stations comprises code for determining a number of reference stations included in the plurality of reference stations. Clause 73: The non-transitory computer-readable medium of clause 72, wherein the number of reference stations is determined based on at least one of a quality of service (QOS), a user request from a mobile device, or an application on the mobile device. Clause 74: The non-transitory computer-readable medium of any of clauses 66 to 73, wherein the code for sending the reference station correction data to the mobile device comprises code for transmitting the reference station correction data to one or more mobile network base stations. Clause 75: A non-transitory computer-readable medium storing instructions for applying real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections at a mobile device, the instructions comprising code for acquiring at the mobile device reference station correction data from each of a plurality of reference stations, where for each reference station, the reference station correction data comprises one or more measurements acquired by a GNSS receiver at the respective reference station; acquiring mobile device measurement data, where the mobile device measurement data comprises one or more measurements acquired by the GNSS receiver at the mobile device; and determining a position of the mobile device based on the reference station correction data from each of the plurality of reference stations and the mobile device measurement data. Clause 76: The non-transitory computer readable medium of clause 75, wherein the code for determining a position of the mobile device comprises code for determining, for each reference station of the plurality of reference stations, an estimated position of the mobile device based on the reference station correction data from the respective reference station and the mobile device measurement data, and determining the position of the mobile device based on the estimated position. Clause 77: The non-transitory computer-readable medium of clause 76, wherein the code for determining a position of the mobile device based on the estimated positions comprises code for taking a simple average or a weighted average of at least some of the estimated positions. Clause 78: The non-transitory computer-readable medium of clause 75, wherein the code for determining a position of the mobile device comprises code for using a single Kalman filter to process reference station correction data from multiple reference stations. Clause 79: The non-transitory computer-readable medium of any of clauses 75-78, wherein the instructions further comprise code for verifying an accuracy of a determined position of the mobile device using carrier-phase integer ambiguities or position vectors from at least two of the plurality of reference stations. Clause 80: The non-transitory computer-readable medium of clause 79, wherein the instructions further comprise code for ignoring the reference station correction data from one or more reference stations of the plurality of reference stations based on verification of an accuracy of the determined position of the mobile device, and determining an improved position of the mobile device based on the remaining reference station correction data from the plurality of reference stations and the mobile device measurement data. Clause 81: The non-transitory computer-readable medium of any of clauses 75-80, wherein the instructions further comprise code for sending a request for reference station correction data to a provider service. Clause 82: The non-transitory computer-readable medium of clause 81, wherein the instructions further comprise code for including information indicative of an approximate location of the mobile device in the request. Clause 83: The non-transitory computer-readable medium of clause 81 or 82, wherein the instructions further comprise code for including in the request at least one of a quality of service (QOS) or a number of reference stations to be included in the plurality of reference stations. Clause 84: The non-transitory computer-readable medium of any of clauses 75 to 83, wherein the code for obtaining reference station correction data from each reference station of the plurality of reference stations comprises code for receiving the reference station correction data from one or more mobile network base stations. Clause 85: The non-transitory computer-readable medium of clause 84, wherein the code for receiving reference station correction data from the one or more mobile network base stations comprises code for repeatedly receiving the reference station correction data from the one or more mobile network base stations. Clause 86: The non-transitory computer-readable medium of clause 85, wherein a repetition rate of receiving the reference station correction data is based on at least one of a bandwidth of wireless communication with one or more mobile network base stations or a performance requirement for determining a position of the mobile device. [Explanation of symbols]

[0125] 100 RTK / DGNSS systems 110 Mobile Devices 110-1 First Mobile Device 110-2 Second Mobile Device 120 Reference station 130 Radio Frequency (RF) Signals 140 Satellite Vehicle (SV) 150 Data Communication Network 160 baseline 170 Service Providers 210 Approximate Mobile Device Location 230 radius 240 Area 320 distance 330 Center of gravity 340 Polygon 360 Center of gravity 505 Beam 505-1a First Beam 505-1b Second Beam 505-2a First Beam 505-2b Second Beam 520 Cellular Base Station 520-1 First base station 520-2 Second base station 540 Area 540-1 First Area 540-2 Second Area 600-1 First Scheduling Method 600-2 Second Scheduling Method 600-3 Third Scheduling Method 600-4 The fourth scheduling method 1105 Bus 1110 Processing Unit 1115 Output Device 1120 Digital Signal Processor (DSP) 1130 Wireless communication interface 1132 Wireless Communication Antenna 1134 Wireless Signal 1140 Sensor 1160 Memory 1170 Input Devices 1180 GNSS Receiver 1182 Antenna 1184 Signal 1200 Computer Systems 1205 Bus 1210 Processing Unit 1215 Input Devices 1220 output device 1225 Non-transient storage devices 1230 Communication Subsystem 1233 Wireless Communication Interface 1235 Working Memory 1240 Operating Systems 1245 Applications

Claims

1. 1. A method for providing reference station correction data for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections to a mobile device, comprising: receiving information indicative of an approximate location of the mobile device or information regarding satellite vehicles visible to the mobile device; selecting a plurality of reference stations from which to obtain the reference station correction data, the selecting being based at least in part on the approximate location of the mobile device or the information regarding satellite vehicles visible to the mobile device; obtaining the reference station correction data from a respective reference station of the plurality of reference stations, wherein for each reference station, the reference station correction data comprises data based on one or more measurements acquired by a GNSS receiver at the respective reference station; sending the reference station correction data to the mobile device; A method for providing the above.

2. The method of claim 1 , wherein the step of selecting a plurality of reference stations is additionally based on a respective position of each of the plurality of reference stations.

3. The method of claim 2 , wherein selecting the plurality of base stations is based on a proximity of the respective positions of each of the plurality of base stations to the approximate position of the mobile device.

4. The method of claim 2 , wherein the plurality of reference stations are selected to minimize a distance between a midpoint or centroid of reference station positions and the approximate position of the mobile device.

5. The method of claim 1 , wherein the plurality of reference stations is selected to maximize a number of common-view GNSS satellites between the mobile device and the plurality of reference stations.

6. to maximize the number of common-view GNSS satellites between the mobile device and the plurality of reference stations; obtaining, from each reference station of the plurality of reference stations, information indicative of GNSS satellites visible by said each reference station; or obtaining, from the mobile device, information indicative of GNSS satellites visible by the mobile device; or Both The method of claim 5 , further comprising:

7. The method of claim 1 , wherein selecting the plurality of reference stations comprises determining a number of reference stations included in the plurality of reference stations.

8. The method of claim 7, wherein the number of reference stations is determined based on at least one of a quality of service (QOS), a user request from the mobile device, or an application of the mobile device.

9. The method of claim 1 , wherein sending the reference station correction data to the mobile device comprises transmitting the reference station correction data from one or more mobile network base stations.

10. the approximate location of the mobile device is within a first coverage area of ​​the one or more mobile network base stations; 10. The method of claim 9, further comprising sending reference station correction data from a plurality of different reference stations to a second mobile device within a second coverage area of ​​the one or more mobile network base stations.

11. 1. A computer server for providing reference station correction data to a mobile device for real-time kinematic (RTK) or differential global navigation satellite system (DGNSS) corrections, comprising: A transceiver; Memory, one or more processing units communicatively coupled to the transceiver and the memory; wherein the one or more processing units: receiving information indicative of an approximate location of the mobile device or information regarding satellite vehicles visible to the mobile device; selecting a plurality of reference stations from which to obtain the reference station correction data, said selecting being based at least in part on the approximate location of the mobile device or the information regarding satellite vehicles visible to the mobile device; obtaining the reference station correction data from a respective reference station of the plurality of reference stations, the reference station correction data comprising, for each reference station, data based on one or more measurements acquired by a GNSS receiver at the respective reference station; sending said reference station correction data to said mobile device via said transceiver; A computer server configured to:

12. The computer server of claim 11 , wherein the one or more processing units are additionally configured to select the plurality of reference stations based on a position of each of the plurality of reference stations.

13. 13. The computer server of claim 12, wherein the one or more processing units are additionally configured to select the plurality of base stations based on a proximity of a position of each of the plurality of base stations to the approximate position of the mobile device.

14. 13. The computer server of claim 12, wherein the one or more processing units are configured to select the plurality of reference stations to minimize a distance between a midpoint or centroid of a reference station position and the approximate position of the mobile device.

15. The computer server of claim 11, further comprising means for executing the method of any one of claims 5 to 10.

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