Portable mobile reference station data service and management method and system

Abstract

The application provides a portable mobile reference station data service and management method and system, relates to the technical field of satellite navigation and high-precision positioning, and comprises the following steps: broadcasting ephemeris and clock difference parameters are parsed according to an interface control file protocol; RTCC SSR data stream is obtained; the RTCC SSR data stream is decoded to obtain SSR correction numbers; the accurate coordinates of a reference station are calculated based on GNSS observation values, satellite navigation messages and the SSR correction numbers; the convergence state of the accurate coordinates of the reference station is evaluated in real time, and parameter configuration is carried out; GNSS observation values are packaged into RTCC MSM4 messages, and are combined and encoded with RTCC 1005 messages packaged from the accurate coordinates of the reference station to generate real-time RTCC differential data stream; and the RTCC differential data stream is broadcast to each terminal through a TCP / IP interface according to an NTRIP protocol. The application realizes high-precision reference station positioning and multi-terminal service.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of satellite navigation and high-precision positioning, and particularly relates to a portable mobile reference station data service and management method and system. BACKGROUND

[0002] With the rapid development of global navigation satellite system (GNSS) technology, high-precision navigation and positioning technologies based on real-time kinematic (RTK) and precise point positioning (PPP) have been widely applied in the fields of transportation, precision agriculture, disaster monitoring, etc. Among them, PPP-RTK technology gradually becomes an efficient high-precision positioning solution by combining the precision of PPP and the real-time performance of RTK. Traditional reference station positioning systems usually rely on fixed sites and complex network deployment, which have the problems of large equipment size, complex deployment, and insufficient real-time performance, and are difficult to meet the needs of high mobility or complex environment areas. In addition, the combination of PPP-RTK service and RTCM (Radio Technical Commission for Maritime Services) data broadcast in the prior art is limited, especially in portable reference stations, there is still a lack of an efficient data interaction and processing mechanism to realize the rapid deployment of reference stations and high-precision positioning functions.

[0003] Therefore, there is an urgent need for a portable reference station data interaction and positioning system and method, which combines cloud-based PPP-RTK service with terminal equipment, supports RTCM data generation and broadcast, and not only meets the requirements of portability and deployment efficiency, but also realizes high-precision reference station positioning and multi-terminal service. SUMMARY

[0004] In order to overcome the problems of large equipment size, complex deployment, and insufficient real-time performance in the prior art, the present application provides a portable mobile reference station data service and management method and system, which can realize accurate coordinate calculation of reference stations, RTCM data stream generation and broadcast, and full-process support for multi-terminal high-precision positioning service, in order to meet the high-precision positioning requirements in actual scenarios, the deployment requirements of reference stations with high mobility, and the technical challenges of efficient data interaction in complex environments.

[0005] In order to achieve the above-mentioned purposes, the present application adopts the following technical solutions:

[0006] A portable mobile reference station data service and management method, comprising the following steps:

[0007] Step 1, the GNSS antenna receives signal transmission to the board card, demodulates to generate GNSS observation value and navigation text, and parses out broadcast ephemeris and clock difference parameters according to the interface control file (ICD) protocol;

[0008] Step 2, the 4G / 5G antenna receives the network signal of the PPP-RTK service end and transmits to the 4G / 5G network card to obtain the RTCM (Radio Technical Commission for Maritime Services, International Maritime Services Radio Technology Commission) SSR (State Space Representation) data stream;

[0009] Step 3, the electric text decoding module decodes the RTCM SSR data stream to obtain the SSR correction number;

[0010] Step 4, the PPP-AR positioning module calculates the accurate coordinates of the reference station based on the GNSS observation value and satellite navigation electric text and the RTCM SSR correction number;

[0011] Step 5, the visualization configuration module evaluates the convergence state of the calculation result of the PPP-AR positioning module in real time, and configures the parameters of the NTRIP Caster (NTRIP caster server) broadcast module;

[0012] Step 6, the electric text packaging and coding module packages the GNSS observation value into the RTCM MSM4 electric text, and combines and encodes the RTCM 1005 electric text packaged from the accurate coordinates of the reference station to generate a real-time RTCM differential data stream;

[0013] Step 7, the NTRIP Caster broadcast module transmits the RTCM differential data stream to each terminal through the TCP / IP interface according to the NTRIP (Internet-based RTCM network transmission protocol) protocol.

[0014] The application also provides a portable mobile reference station data service and management system, comprising:

[0015] The electric text decoding module is connected with the PPP-AR positioning module and is used for decoding the RTCM SSR data stream transmitted by the 4G / 5G network card to obtain the corresponding SSR correction number;

[0016] The PPP-AR positioning module is used for receiving and processing the GNSS observation value output by the GNSS board card, the satellite navigation electric text and the SSR correction number output by the electric text decoding module, and calculating the accurate coordinates of the reference station through the PPP-AR algorithm;

[0017] The electric text packaging and coding module is connected with the PPP-AR positioning module and the GNSS board card, and is used for packaging the accurate coordinates of the reference station into the RTCM 1005 electric text, packaging the GNSS observation value generated by the GNSS board card into the RTCM MSM4 electric text, and combining and encoding the two to generate an RTCM differential data stream;

[0018] An NTRIP Caster broadcasting module, connected with the message packaging and encoding module, is configured to broadcast the RTCM differential data stream to an external terminal device through a network communication interface according to an NTRIP protocol.

[0019] A visual configuration module, connected with the PPP-AR positioning module and the NTRIP Caster broadcasting module, is configured to provide a human-computer interaction interface, monitor the convergence of the PPP-AR solving state in real time, and configure and manage system operation parameters and broadcasting parameters.

[0020] The application further provides an electronic device, which comprises:

[0021] at least one processor; and

[0022] a memory in communication with the at least one processor; wherein

[0023] the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the portable mobile reference station data service and management method.

[0024] The application further provides a non-transitory computer readable storage medium storing computer instructions for causing a computer to perform the portable mobile reference station data service and management method.

[0025] Advantages:

[0026] The application integrates a PPP-AR (precise point positioning ambiguity fixing) high-precision positioning algorithm and a cloud-based PPP-RTK service, realizes autonomous centimeter-level coordinate solving of a reference station under no known point condition and real-time generation and broadcasting of an RTCM differential data stream, has the capabilities of rapid deployment, multi-system compatibility and multi-terminal concurrent service, effectively solves the problems of strong dependence on fixed infrastructure, complicated deployment and difficulty in guaranteeing absolute accuracy in a traditional operation mode, and significantly improves the practicability, reliability and operation efficiency of the reference station in scenarios such as precision agriculture, intelligent driving, engineering surveying and emergency mapping. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 A flowchart of a portable mobile reference station data service and management method of the application;

[0028] Figure 2 A working logic diagram of a portable mobile reference station data service and management system of the application. DETAILED DESCRIPTION

[0029] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other. The present application will be further described below with reference to the drawings and embodiments.

[0030] The present application is realized based on a portable mobile reference station. The hardware platform of the portable mobile reference station includes GNSS antennas, GNSS board cards, 4G / 5G antennas, 4G / 5G network cards and other hardware components, and text decoding modules, PPP-AR positioning modules, text packaging and encoding modules, NTRIP Caster broadcasting modules and visual configuration modules. The text decoding module decodes the RTCM SSR data stream received from the 4G / 5G network card and obtains the SSR correction number; the PPP-AR positioning module receives and processes the observation data of the GNSS board card and the SSR correction number of the text decoding module, and outputs the accurate coordinates of the portable mobile reference station; the text packaging and encoding module packages and encodes to generate a standard format RTCM differential data stream; the NTRIP Caster broadcasting module broadcasts the encoded RTCM differential data stream to external terminal equipment; and the visual configuration module provides a human-computer interaction interface for monitoring system status and configuration parameters.

[0031] As shown in Figure 1 The present application provides a portable mobile reference station data service and management method, which includes the following steps:

[0032] Step 1, the GNSS antenna receives signals and transmits them to the multi-system multi-frequency GNSS board card to demodulate GNSS observation values and navigation text, and parse the broadcast ephemeris and clock difference parameters according to the interface control file (ICD) protocol, which includes the following steps:

[0033] Step 1.1, the GNSS measurement choke ring antenna arranged on the portable mobile reference station is connected to the multi-system multi-frequency GNSS board card in its interior through a radio frequency cable.

[0034] Step 1.2, the multi-system multi-frequency GNSS board card receives and tracks the L1 / L2 frequency point signals of all visible GPS (Global Positioning System), BDS (Beidou Satellite Navigation System) and Galileo (Galileo Satellite Navigation System) satellites, and generates original observation data containing pseudorange, carrier phase, Doppler shift and signal-to-noise ratio in real time through baseband processing.

[0035] Step 1.3, the multi-system multi-frequency GNSS board card synchronously demodulates the navigation message bit stream in the satellite signal, and parses out the broadcast ephemeris and broadcast clock difference parameters according to the ICD-GPS-200 (Global Positioning System Space Signal Interface Control Document) protocol of GPS, the BDS (BeiDou Satellite Navigation System Space Signal Interface Control Document) of BDS, and the Galileo Open Service Signal In Space Interface Control Document (Galileo Open Service Signal Interface Document) of Galileo.

[0036] Step 2, transmitted to the 4G / 5G network card to obtain the RTCM SSR data stream, including the following steps:

[0037] Step 2.1, the portable reference station initiates a Socket connection request to the server IP address and port (such as ntrip.xxxx.com:2101) of the cloud PPP-RTK service provider (such as Qianxun Position, Liufen Technology) through the Quectel RM500Q 4G / 5G network card (connected to the Internet, based on TCP / IP protocol).

[0038] Step 2.2, the built-in NTRIP Client software module sends an authentication request containing the target mount point name, username and password to the server through the HTTP / 1.1 protocol (for example: GET / RTCM32-GGB HTTP / 1.1).

[0039] Step 2.3, after authentication, continuously receive the data stream broadcast by the server in the RTCM 3.3 standard format. The data stream mainly contains RTCM 1057 (SSR orbit correction number), 1058 (SSR clock correction number), 1060 (SSR phase bias correction number) series of messages.

[0040] Step 3, decode the RTCM SSR data stream to obtain the SSR correction number, including:

[0041] Step 3.1, the message decoding module performs cyclic redundancy check (CRC) on the received message, and after verification, parses according to the message number, separates and extracts the precise orbit correction number ΔX, ΔY, ΔZ, precise clock correction number δt, phase bias correction number UPD, etc.

[0042] Step 4, the PPP-AR positioning module calculates the accurate coordinates of the reference station based on GNSS observation values, satellite navigation messages and SSR correction numbers, including the following steps:

[0043] Step 4.1, PPP-AR positioning module (using RTKLIB (Real-Time Kinematic Library), PRIDE-PPPAR (High-Precision Real-Time Kinematic Precise Point Positioning Ambiguity Resolution Tool) or commercial software engine) performs data preprocessing on the raw observation data generated in Step 1.2, including signal-to-noise ratio threshold screening, cycle slip detection and marking, to obtain preprocessed observation data, and calculates the rough position and clock error of the satellite in combination with the satellite navigation message.

[0044] Step 4.2, the PPP-AR positioning module fuses the preprocessed observation data, the broadcast ephemeris of Step 1.3, and the precise orbit correction numbers ΔX, ΔY, ΔZ, precise clock correction numbers δt, and phase bias correction numbers UPD, to generate accurate satellite position and time information using precise orbit correction numbers and precise clock correction numbers.

[0045] Step 4.3, construct an ionosphere-free combined observation model, use an extended Kalman filter (EKF) for parameter estimation, and solve the receiver position, clock error, troposphere delay and carrier phase float ambiguity in real time. Then, use the LAMBDA (Least Squares) algorithm to search and fix the integer ambiguity of each frequency, and finally output the reference station's centimeter-level three-dimensional coordinates in the ITRF (International Terrestrial Reference Frame) framework.

[0046] Step 5, the visualization configuration module evaluates the convergence state of the PPP-AR positioning module in real time, and configures the parameters of the NTRIP Caster broadcast module, including the following steps:

[0047] Step 5.1, the visualization configuration module developed based on QT (Qt Creator, cross-platform C++ graphical user interface application development framework) (real-time graphical display of PPP-AR solution results, posteriori unit weight variance, ambiguity fixing rate Ratio, and position convergence in east, north and sky directions.

[0048] Step 5.2, when the monitoring indicators are stable (for example: horizontal accuracy < 2 cm, vertical accuracy < 3 cm, and maintained for more than 60 seconds), the interface prompts "system convergence, service ready".

[0049] Step 5.3, the user inputs the broadcast parameters of the NTRIP Caster broadcast module through the interface, including: establishing a mount point list (including mount point names such as TEST01), setting network parameters (including port numbers such as 2101), setting authentication information (including username and password), and configuring data stream parameters (such as the output frequency of 1 Hz of the differential data stream).

[0050] Step 6, the message encapsulation and encoding module encapsulates the GNSS observations into RTCM MSM4 messages and combines them with the RTCM 1005 messages encapsulated from the reference station precise coordinates to generate real-time RTCM differential data stream, including the following steps:

[0051] Step 6.1, the message encapsulation and encoding module obtains the multi-system raw observations generated by the multi-system GNSS board in real time.

[0052] Step 6.2, the message encapsulation and encoding module calls the board SDK (software development kit) or built-in encoding library to encapsulate the observations into observation messages according to the RTCM MSM4 standard (GPS: 1074, BDS: 1124, Galileo: 1094) (MSM4 type observation message of GPS, MSM4 type observation message of BDS, MSM4 type observation message of Galileo); at the same time, the reference station centimeter-level three-dimensional coordinates obtained in step 3.3 are encapsulated according to the RTCM 1005 message format.

[0053] Step 6.3, the RTCM 1005 message is used as the reference station information header, and the subsequent continuously generated MSM4 observation messages are arranged in time sequence, to generate a continuous differential data stream conforming to the RTCM 3.3 standard.

[0054] Step 7, the NTRIP Caster broadcasting module broadcasts the RTCM differential data stream to each terminal through the TCP / IP interface according to the NTRIP protocol, including the following steps:

[0055] Step 7.1, the NTRIP Caster broadcasting module such as BNC (Beidou Network Clock NTRIP Client and broadcaster) or SNIP (Simple NTRIP Internet Protocol broadcaster) is started in the background of the portable reference station, loads the mount point list and authentication information established in step 4.3, and listens for connections on the specified port.

[0056] Step 7.2, the continuous differential data stream generated in step 6.3 is pushed to the NTRIP Caster broadcasting module in a ring buffer manner.

[0057] Step 7.3, the NTRIP Caster broadcasting module broadcasts the data stream in the form of TCP packets to the Internet in real time through the uplink network link established by the 4G / 5G card according to the NTRIP protocol. The external RTK mobile station (terminal) as the NTRIP Client can access and receive centimeter-level differential services by inputting the same mount point information and IP address.

[0058] Embodiment:

[0059] In an embodiment of the present application, the present application is used in a mountain disaster emergency monitoring system to realize high-precision reference station positioning and real-time data interaction.

[0060] After the rescue team arrives at the safe area outside the landslide, the portable reference station is quickly deployed. After the power is turned on, the devices of the portable reference station automatically receive satellite signals through the GNSS antenna, and successfully access the cloud PPP-RTK service through the 4G network (in the area without public network coverage, the satellite communication module can be used as a backup link), and receive the SSR correction number.

[0061] The device completes the PPP-AR convergence within 15 minutes, and the visual interface displays that the three-dimensional coordinate accuracy is better than 2 cm, and the system prompts "ready". The technician connects the Wi-Fi hotspot of the device through the tablet computer, accesses the web configuration interface, and confirms that the coordinates are correct.

[0062] The technician simply sets the mounting point to LANDSLIDE_01 and the password to the temporary instruction in the interface. The device immediately starts to broadcast the differential stream containing BDS / GPS dual-system data.

[0063] The unmanned aerial vehicle is equipped with an RTK terminal and is connected to the reference station LANDSLIDE_01 through the network RTK mode, so that the landslide displacement monitoring and orthographic image aerial survey with centimeter-level accuracy can be performed in the area without a map, and the data is transmitted to the command center in real time. During the whole process, the Beidou / GNSS reference station is established, and there is no need for long-term observation and post-processing of precise coordinates, which greatly shortens the emergency response time and provides a crucial high-precision spatial reference for disaster research and judgment.

[0064] As shown in Figure 2 The present application also provides a portable mobile reference station data service and management system for realizing the above method, comprising the following modules:

[0065] The text decoding module is used for decoding the RTCM SSR data stream transmitted by the 4G / 5G network card to obtain the corresponding SSR correction number;

[0066] The PPP-AR positioning module is used for receiving and processing the GNSS observation value, satellite navigation text and RTCM SSR correction number data stream output by the 4G / 5G network card, and calculating the accurate coordinates of the reference station through the PPP-AR algorithm;

[0067] The electric text packaging and coding module is connected with the PPP-AR positioning module and the GNSS board card, and is used for packaging the accurate coordinates of the reference station into RTCM 1005 electric text, packaging GNSS observation values generated by the GNSS board card into RTCM MSM4 electric text, and then combining and coding the two to generate an RTCM differential data stream;

[0068] The NTRIP Caster broadcasting module is connected with the electric text packaging and coding module, and is used for broadcasting the RTCM differential data stream to external terminal devices (terminal 1-terminal N) through a network communication interface according to an NTRIP protocol. Figure 2

[0069] The visual configuration module is connected with the PPP-AR positioning module and the NTRIP Caster broadcasting module, and is used for providing a human-computer interaction interface, monitoring the convergence of the PPP-AR solving state in real time, and configuring and managing system operation parameters and broadcasting parameters.

[0070] The application further provides an electronic device, which comprises at least one processor and a memory connected with the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the portable mobile reference station data service and management method.

[0071] The application further relates to a non-transitory computer readable storage medium storing computer instructions for enabling the computer to execute the portable mobile reference station data service and management method.

[0072] Those skilled in the art should understand that the embodiments of the application can be provided as a method, a system or a computer program product. Therefore, the application can adopt a completely hardware embodiment, a completely software embodiment or an embodiment combining software and hardware aspects. Moreover, the application can adopt a computer program product in the form of one or more computer usable storage media containing computer usable program codes (including but not limited to disk storage, CD-ROM, optical storage, etc.). The solutions in the embodiments of the application are recommended to be realized by using C / C++ and JAVA languages.​

Claims

1. A portable mobile reference station data service and management method, characterized by, Comprise the following steps: Step 1, GNSS antenna receives signals and transmits to multi-system multi-frequency GNSS board card, demodulation generates GNSS observation value and navigation text, and parses broadcast ephemeris and clock difference parameters according to interface control file protocol; Step 2, 4G / 5G antenna receives the network signal of PPP-RTK server, and transmits to 4G / 5G network card to obtain RTCM SSR data stream; RTCM represents standard format message, and SSR represents state space representation; RTK represents real-time dynamic positioning, and PPP represents precise point positioning; Step 3, decode RTCM SSR data stream to obtain SSR correction number, including: Step 3.1, cyclic redundancy check verification is carried out on the received RTCM SSR data stream, and after verification, the text type is parsed, and the precise orbit correction number, precise clock correction number, phase bias correction number and code bias correction number are separated and extracted; Step 4, based on GNSS observation value and satellite navigation text and SSR correction number, the accurate coordinates of the reference station are calculated, including: Step 4.1, data quality screening, cycle slip detection and repair are carried out on GNSS observation data, and the rough position and clock difference of satellite are calculated by using satellite navigation text; Step 4.2, precise satellite position and clock difference information are generated by using precise orbit correction number and precise clock correction number in step 3.1; Step 4.3, the precise satellite information, phase bias correction number and preprocessed GNSS observation data are fused to construct an ionosphere-free combined observation model, and parameter estimation is carried out through extended Kalman filter, and least square method is used to search fixed integer ambiguity, and finally the accurate coordinates of the reference station are solved; Step 5, the convergence state of the accurate coordinates of the reference station is evaluated in real time, and parameter configuration is carried out; Step 6, the GNSS observation value is packaged into RTCM MSM4 text, and is combined and encoded with RTCM1005 text packaged from the accurate coordinates of the reference station to generate real-time RTCM differential data stream; Step 7, according to NTRIP protocol, the RTCM differential data stream is broadcast to each terminal through TCP / IP interface; NTRIP protocol is an RTCM network transmission protocol based on Internet.

2. The portable mobile reference station data service and management method of claim 1, wherein, The step 2 comprises: Step 2.1, the 4G / 5G network card initiates a connection request to the specified IP address and port of the PPP-RTK server based on TCP / IP protocol; Step 2.2, an NTRIP authentication request containing mounting point, username and password is sent to the PPP-RTK server through HTTP protocol; Step 2.3, after authentication, the RTCM SSR data stream broadcast by the PPP-RTK server is received, which contains the text of orbit correction number, clock difference correction number, phase bias correction number and code bias correction number.

3. The portable mobile reference station data service and management method of claim 1, wherein, The step 5 comprises: Step 5.1, the posteriori unit weight variance of the accurate coordinates of the reference station, the ambiguity fixing rate and the convergence accuracy of the three-dimensional coordinate components of east, north and sky direction of the solution result are monitored in real time; Step 5.2, when all monitoring indicators are continuously lower than the preset threshold and maintain for more than a predetermined time, it is determined that the convergence is completed, and a system ready signal is generated, outputting the precise coordinates of the reference station; Step 5.3, receiving user input through a graphical user interface, configuring mount point name, port number, username and password, and setting output frequency of differential data stream.

4. The portable mobile reference station data service and management method of claim 1, wherein, The step 6 comprises: Step 6.1, receiving real-time GNSS observation values from the board card, and packaging in RTCM MSM4 message format, the message including pseudo-range, carrier phase observation value and signal-to-noise ratio; Step 6.2, receiving the precise coordinates of the reference station, and packaging into RTCM 1005 message format; Step 6.3, combining and arranging the RTCM 1005 message as a message header with the RTCM MSM4 message according to the RTCM protocol standard, to generate a continuous RTCM differential data stream.

5. The portable mobile reference station data service and management method of claim 1, wherein, The step 7 comprises: Step 7.1, starting broadcasting, listening to the specified port, and loading the mount point list, username and password configured in step 5 from the configuration file; Step 7.2, using the RTCM differential data stream generated in step 6 as a data source for broadcasting; Step 7.3, according to the NTRIP protocol, continuously broadcasting the RTCM differential data stream to the Internet in the form of TCP data packets through the 4G / 5G network card network communication interface; Step 7.4, after the terminal device is authenticated by HTTP Basic authentication as an NTRIP Client, a TCP long connection is established to access and receive the differential data stream.

6. A portable mobile reference station data service and management system for implementing the method of any one of claims 1 to 5, characterized by Comprise: The message decoding module is connected with the PPP-AR positioning module, and is used for decoding the RTCM SSR data stream transmitted by the 4G / 5G network card to obtain corresponding SSR correction number; The PPP-AR positioning module is used for receiving and processing GNSS observation values, satellite navigation messages output by the GNSS board card and SSR correction numbers output by the message decoding module, and obtaining the precise coordinates of the reference station through PPP-AR algorithm solution; PPP-AR represents ambiguity fixed in precise point positioning; The message packaging and encoding module is connected with the PPP-AR positioning module and the GNSS board card, and is used for packaging the precise coordinates of the reference station into RTCM 1005 message, and packaging the GNSS observation values generated by the GNSS board card into RTCM MSM4 message, and then combining and encoding the two to generate an RTCM differential data stream; The NTRIP Caster broadcasting module is connected with the message packaging and encoding module, and is used for broadcasting the RTCM differential data stream to external terminal devices through the network communication interface according to the NTRIP protocol; The visual configuration module is connected with the PPP-AR positioning module and the NTRIP Caster broadcasting module, and is used for providing a human-computer interaction interface, monitoring the convergence of the PPP-AR solution state in real time, and configuring and managing system running parameters and broadcasting parameters.

7. An electronic device, comprising: The electronic device comprises: at least one processor; and a memory in communication with the at least one processor; wherein The memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the portable mobile reference station data service and management method of any one of claims 1-5.

8. A non-transitory computer-readable storage medium, comprising: The non-transitory computer readable storage medium stores computer instructions for causing the computer to perform the portable mobile reference station data service and management method of any one of claims 1-5.

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