KR100503195B1 - Geographical information system providing correction data for real time coordinates correction based on dgps and iocp communication - Google Patents

Abstract

A geographic information system is published that provides correction data for real-time coordinate correction based on Digi-PS and IOS communications. The geographic information system of the present invention includes a plurality of DGPS correction data collection stations. The DGPS correction data collection station receives medium wave signals transmitted from a plurality of reference stations, collects the DGPS correction data, and provides the DGPS correction data to the central server through the TCP / IP network. The central server communicates with the mobile station terminal in an IOCP communication manner and provides corresponding DGPS correction data in response to a request of the mobile station terminal. The mobile station performs coordinate correction in real time using the DGPS correction data provided by the IOCP communication method.

Description

GEOGRAPHICAL INFORMATION SYSTEM PROVIDING CORRECTION DATA FOR REAL TIME COORDINATES CORRECTION BASED ON DGPS AND IOCP COMMUNICATION}

The present invention relates to a geographic information system based on a digital GPS (DGPS), specifically, a pseudo-distance correction value, which is DGPS correction data provided from a reference station through a plurality of DGPS correction data collection stations, is collected into a central server. And a DGPS correction value information collection for providing corresponding correction data for real-time coordinate correction to a mobile station using an IOCP communication method, and a real-time coordinate correction geographic information system using an ICP communication method.

GPS (Global Positioning System) is a satellite positioning system that knows exactly where you are using satellites anywhere in the world, not just airplanes, ships and cars. GPS was developed by the US Department of Defense as a system for military purposes, but today it has been approved by the US Congress and used in the civilian, on the premise of opening some to civilians. Early GPS was difficult to get accurate position due to various error factors. Accordingly, various methods for obtaining more accurate location information have been developed, and DGPS (Differential GPS) is now widely used.

DGPS is a navigation system that enables more accurate positioning using pseudorange correction values sent from a reference station whose location is known. After receiving the GPS signal from the satellite, the reference station calculates the pseudo range correction value based on its accurate measured position and GPS signal, and transmits it to the mobile terminal in the RTCM (Radio Technical Commission for Maritime Service) format. do. The mobile station terminal corrects the coordinates by reflecting this information in its position calculation.

Currently, the RF beacon (BEACON) method is most commonly used as a communication means for the correction process of the DGPS, which uses a radio frequency method for transmitting a correction signal to a radio wave of a predetermined frequency band. However, in the conventional method, the installation process of the DGPS equipment is complicated, and blind spots are generated due to a building or radio interference, and an error occurs as the distance from the reference station increases. In addition, power consumption is known to have a number of disadvantages, such as paying close attention to power management.

Various methods for improving the problems of the communication method using the RF beacon have been proposed. Korean Patent Application No. 10-1998-15794 discloses a method of calibrating a GPS signal using a CDMA mobile phone. However, since this method supports only one-to-one communication between the reference station and the GPS receiver, communication disconnection frequently occurs during the call for mutual communication, which makes it difficult to use in practice.

Korean Patent Application No. 10-2004-41706 discloses a digital PS system using the wireless Internet. This system is a method of transmitting correction information from a reference station to a terminal such as a PDA in a CDMA manner. In this method, a CDMA signal is sent to the server at the request of the user, and the server selects a bidirectional scheme in which the server needs to receive information from the reference station. However, since the time required for CDMA connection is about 2 to 3 seconds, and after receiving the reference station information, it is difficult to provide correction information data in real time. In addition, the cost factor is high because of the CDMA call requested by the user and the CDMA call sent back to the user.

Therefore, in the DGPS-based geographic information system, the present invention collects DGPS correction data provided from a reference station to a central server through a plurality of DGPS correction data collection stations, and applies correction data corresponding to a request of a mobile station terminal in an IOCP communication method. The purpose of the present invention is to provide an improved geographic information system in which a mobile station terminal can perform stable and high precision real-time coordinate correction by providing the mobile station terminal through a CDMA mobile communication network.

One aspect of the present invention for achieving the above technical problem relates to a geographic information system for providing correction data for real-time coordinate correction. The geographic information system of the present invention comprises: a plurality of DGPS correction data collection stations that receive medium wave signals transmitted from a plurality of reference stations, collect DGPS correction data, and output them through a TCP / IP network; A central server for collecting the DGPS correction data collected from the plurality of DGPS correction data collection stations; And a mobile station terminal communicating with the central server through a CDMA communication network in an IOCP communication manner, wherein the central server receives DGPS correction data provided from a reference station closest to the current position of the mobile station terminal in response to a request for transmitting the DGPS correction data of the mobile station terminal. It provides correction data for real-time coordinate correction based on the digital PS and IOS communication provided to the mobile station.

Advantageously, said DGPS correction data collection station comprises: at least one medium wave receiver for receiving medium wave signals transmitted from a reference station; At least one radio conversion transmitter for converting DGPS correction data in a serial data format output from the medium wave receiver into a radio signal; And a wireless sharing receiver for transmitting DGPS correction data in serial data format transmitted from one or more radio conversion transmitters to a central server via a TCP / IP network.

Preferably, the central server comprises: a collection station manager for collecting and managing DGPS correction data provided from a plurality of DGPS correction data collection stations via a TCP / IP network; A mobile station manager which manages access to the mobile station terminal through the CDMA communication network by an IOCP communication method, and processes user authentication of the mobile station terminal; A shortest base station selecting unit selecting a reference station closest to the mobile station terminal; And a real-time correction value transmitter for providing corresponding DGPS correction data in real time in response to a request of the mobile station.

Preferably, the mobile station terminal is connected to the central server via a CDMA communication network in accordance with the IOCP communication scheme to receive GPS information from the mobile communication block and the satellite receiving the DGPS correction data, and to perform coordinate correction based on the DGPS correction data. And a GPS block, and the mobile communicator block receives coordinate information corrected from the GPS block to display geographic information.

DETAILED DESCRIPTION In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the embodiments of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the accompanying drawings. In understanding the drawings, it should be noted that like parts are intended to be represented by the same reference numerals as much as possible. Detailed descriptions of well-known functions and configurations that are determined to unnecessarily obscure the subject matter of the present invention will be omitted.

(Example)

Hereinafter, by explaining a preferred embodiment of the present invention with reference to the accompanying drawings, a geographic information system for providing correction data for real-time coordinate correction of the present invention will be described in detail.

1 is a block diagram schematically showing the overall configuration of a geographic information system according to a preferred embodiment of the present invention. Referring to FIG. 1, the geographic information system of the present invention is largely composed of a plurality of reference stations 20, a plurality of DGPS correction data collection stations 30, a central server 50, and a mobile station terminal 100. And the GIS tool 60 is used auxiliary.

A plurality of reference stations 20 are installed at a point where the exact position is known, and transmits by calculating and transmitting correction error values such as orbital errors, time errors, and propagation delay errors from the GPS information provided from each satellite 10. The station uses Radio BEACON frequency of 285 ~ 325kHz and transmits it with BEACON signal. In Korea, about 12 such reference stations are installed and operated. In the present invention, the DGPS correction data (RTCM correction data) is collected using the medium wave signal transmitted from the reference station 20.

The plurality of DGPS correction data collection stations 30 collects respective DGPS correction data from medium frequency signals (radio beacons) transmitted from the plurality of reference stations 20, and transmits the respective DGPS correction data through the TCP / IP network 40 to the central server 50. To provide.

The central server 50 collects and manages the DGPS correction data provided from the plurality of DGPS correction data collection stations 30 and any one closest to the corresponding mobile station terminal 100 in response to a request of the mobile station terminal 100. The DGPS correction data provided from the reference station 20 is provided to the mobile station terminal 100 through the CDMA communication network 45 in real time based on the IOCP communication method.

The mobile station terminal 100 communicates with the central server 50 via the CDMA communication network 45 and performs stable and accurate real time coordinate correction using the DGPS correction data provided from the central server 50.

The GIS tool 60 may monitor the measured value by downloading the DGPS information measured by the mobile station terminal 100, and process and manage drawing control, coordinate transformation, vector editing, etc. which are general functions of the GIS.

FIG. 2 is a block diagram illustrating a detailed configuration of the DGPS correction data collection unit of FIG. 1. Referring to FIG. 2, the DGPS correction data collection station 30 includes one or more medium wave receivers 31, one or more radio conversion transmitters 32, and a wireless sharing receiver 33.

One or more medium wave receivers 31 interpret the radio beacon signal, which is a medium wave signal transmitted from the reference station 20, and convert the DGPS correction data into serial communication data. The at least one radio conversion transmitter 32 converts the DGPS correction data in the form of serial information provided from the medium wave receiver 31 into a radio signal and transmits the radio signal to the radio sharing receiver 33. The radio sharing receiver 33 transmits the information collected from the one or more radio conversion transmitters 32 to the central server 50 through the TCP / IP network 40. The radio sharing receiver 33 communicates with one or more radio conversion transmitters 32 based on a Bluetooth communication scheme, and distinguishes each device by a communication port number.

3 is a flowchart illustrating a control procedure of the DGPS correction data collection unit. Referring to FIG. 3, at step S10 one or more medium wave receivers 31 receive medium wave signals transmitted from a plurality of reference stations 20. In step S11, the medium wave receiver 31 analyzes the received medium wave signal, obtains the DGPS correction data, converts it into a serial signal, and provides the converted radio signal to the corresponding radio conversion transmitter 32. In step S12, the radio conversion transmitter 32 converts the provided serial DGPS correction data into a radio signal and transmits the radio signal to the radio sharing receiver 33. In step S13, the wireless sharing receiver 33 transmits the DGPS correction data in serial form received from the one or more radio conversion transmitters 32 to the central server 50 through the TCP / IP network 40.

4 is a block diagram illustrating a configuration of a central server of FIG. 1. Referring to FIG. 4, the central server 50 is largely composed of a collection station manager 51, a mobile station manager 52, a shortest-range reference station analyzer 53, and a real-time correction value transmitter 54.

The central server 50 manages the DGPS correction data provided from the plurality of DGPS correction data collection units 30 for each channel. The central server 50 asynchronously outputs DGPS correction data provided from the reference station 30 closest to where the mobile station terminal 100 is located in response to a request for providing the DGPS correction data of the mobile station terminal 100. Provided in real time based on the communication method.

The problem with the general client / server method is that it is difficult to transmit in real time due to the large overhead due to frequent context switching between contexts. To overcome this problem, asynchronous IOCP was introduced. In the geographic information system of the present invention, the central server 50 and the mobile station terminal 100 communicate based on the asynchronous IOCP communication method. The collection station manager 51 manages the DGPS correction data provided from the plurality of DGPS correction data collection stations 30 for each reference station 20 and maintains and manages the latest DGPS correction data at a constant size (N byte). .

The mobile station manager 52 processes initial user authentication upon connection of the mobile station terminal 100, manages communication connection with the mobile station terminal 100 in a connection mode or a correction mode according to the state of the mobile station terminal 100, and performs CDMA communication. Due to the nature of the connection, check the disconnection and decide whether to reconnect and remove the connection completely. The shortest distance reference station analyzer 53 selects the best reference station by calculating the actual distance between the reference station 20 and the mobile station terminal 100. The real-time correction value transmitter 54 transmits the DGPS correction data in real time at regular intervals according to the request of the mobile station terminal 100.

5 is a flowchart showing the control procedure of the central server. In step S20, the collection station manager 51 receives the DGPS correction data provided from the plurality of DGPS correction data collection stations 30 through the TCI / IP network 40 and manages each data for each reference station 20.

When the mobile station terminal 100 connects in step S21, the mobile station manager 52 performs a user authentication process. The user authentication process can, for example, authenticate the mobile station by the CDMA terminal number. If user authentication is made, in step S22 the shortest base station analyzer 53 selects and maintains the closest reference station 20 according to the position of the mobile station terminal 100. In step S23, the mobile station manager 52 continuously checks the state of the mobile station terminal 100 at regular intervals in order to maintain communication connection in accordance with the request of the mobile station terminal 100. FIG.

In step S24, the DGPS correction data provided from the reference station 20 selected in accordance with the request of the mobile station terminal 100 is provided to the mobile station terminal 100. FIG. In step S25, in response to the request of the mobile station terminal 100, the communication connection with the mobile station terminal 100 is released.

6 is a block diagram showing the configuration of the mobile station terminal of FIG. Referring to FIG. 6, the mobile station terminal 100 is largely composed of a mobile communicator block 101 and a GPS block 102. The mobile communication block 101 may be constituted by, for example, a mobile communication terminal such as a PDA. The GPS block 102 is a block that receives the GPS signal transmitted from the satellite 12.

In detail, the mobile communication block 101 includes a CDMA communication unit 110, an internal processing module 120, a memory device 131, a first power supply and charging device 140, and a first display device 150. do.

The CDMA communication unit 110 communicates with the central server 50 through the CDMA communication network 45 based on the IOCP communication method, receives the DGPS correction data in real time, and transmits the current location information of the mobile station terminal 100 itself to the central server ( 50) to select the optimal reference station 20. The internal processing module 120 sets up a communication environment of the mobile station terminal 100 such as coordinate transformation and communication port setting for correctly checking the coordinates of the WGS84.

The memory device 130 stores data such as DGPS correction data and coordinate information. The first power supply and charging device 140 receives power from the first external power source 141 to charge the internal rechargeable battery, and the operating power is supplied to the mobile communication block 101 from the internal rechargeable battery. The first display device 150 displays the satellite state of the GPS and the coordinates and geographic information where the mobile station terminal 100 is located.

The GPS block 102 includes a second display device 160, a communication level converting and port integration device 170, a GPS receiver 180, and a second power supply and charging device 190.

The second display device 160 displays various states such as a power supply, a charging state, and a transmission / reception state related to the GPS with LEDs. The communication level conversion and port integration device 170 converts the communication voltage level for the interface with the mobile communication block 101. The GPS receiver 180 receives a GPS signal provided from the satellite 12 and performs coordinate correction based on the DGPS correction data provided in real time.

The second power supply and charging unit 190 charges and drives another internal rechargeable battery at a DC 5V-16V through the second external power supply 191, and charges using a DC adapter indoors, and a cigar jack of a vehicle while moving. Can be charged by connecting to.

7 is a flowchart showing a control procedure of a mobile station terminal. Referring to FIG. 7, in step S30, the mobile communication block 101 accesses the central server 50 through the CDMA communication network 45 and receives user authentication using the CDMA terminal number. In step S31, the connection mode with the central server 50 is maintained, and in step S32, the DGPS correction data is received during the set time in the transmission mode, and when the time ends, the mode is switched to the connection mode. In step S33, the optimal DGPS correction data received from the central server 50 is transmitted to the GPS block 102 in the transmission mode.

In S34, location information and status information are received from the GPS block 102. In operation S35, the information received from the GPS block 102 is analyzed and the necessary information is output to the screen of the first display apparatus 150. In operation S36, the GPS-related information is stored in the memory device 130 when the user requests it. In step S37, the mobile station terminal 100 switches to the transmission mode in accordance with the user's request, and the time for maintaining the transmission mode is also extended, and when the designated time is completed, the mobile station terminal 100 automatically switches to the connection mode.

As described above, the present invention has been described with reference to the embodiments shown in the drawings, but this is merely exemplary, and those skilled in the art to which the present invention pertains have various modifications and equivalent embodiments. You can see that it is possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

According to the geographic information system of the present invention as described above, DGPS correction data is independently collected through a plurality of DGPS correction data collection stations, and transmitted to a central server through a TCP / IP network in terms of communication cost compared to the prior art. Very significant cost savings can be achieved. In addition, since the central server collects the DGPS correction data in real time and provides the DGPS correction data to the mobile station in the unit of time less than 1 second, it has 4 to 5 times more efficiency than the conventional method in providing the real time correction information data service. Can give

In order to more fully understand the drawings used in the detailed description of the invention, a brief description of each drawing is provided.

1 is a block diagram schematically showing the overall configuration of a geographic information system according to a preferred embodiment of the present invention.

FIG. 2 is a block diagram illustrating a detailed configuration of the DGPS correction data collection unit of FIG. 1.

3 is a flowchart illustrating a control procedure of the DGPS correction data collection unit.

4 is a block diagram illustrating a configuration of a central server of FIG. 1.

5 is a flowchart showing the control procedure of the central server.

6 is a block diagram showing the configuration of the mobile station terminal of FIG.

7 is a flowchart showing a control procedure of a mobile station terminal.

* Description of the symbols for the main parts of the drawings

10, 12: satellite 20: reference station

30: DGPS correction data collection station 40: TCP / IP network

45: CDMA network 60: GIS tool

100: mobile station terminal

Claims (4)

A plurality of DGPS correction data collection stations that receive the medium wave signals transmitted from the plurality of reference stations, collect DGPS correction data, and output them through a TCP / IP network; A central server for collecting the DGPS correction data collected from the plurality of DGPS correction data collection stations; A mobile station terminal which performs communication in a IOCP communication manner through a central server and a CDMA communication network, The central server provides the correction data for real-time coordinate correction based on the digital PS and IOS communication which provides the corresponding mobile station with the DGPS correction data provided from the reference station closest to the current position of the mobile station according to the request for transmitting the DGPS correction data of the mobile station. Providing geographic information system. The apparatus of claim 1, wherein the DGPS correction data collection station is: One or more medium frequency receivers for receiving medium frequency signals transmitted from a reference station; At least one radio conversion transmitter for converting DGPS correction data in a serial data format output from the medium wave receiver into a radio signal; And Providing correction data for real-time coordinate correction based on digital PS and IOS communication including a wireless sharing receiver for transmitting DGPS correction data in serial data format transmitted from one or more radio conversion transmitters to a central server through a TCP / IP network. Geographic information system. The system of claim 1, wherein the central server is: A collection station manager that collects and manages DGPS correction data provided from a plurality of DGPS correction data collection stations through a TCP / IP network; A mobile station manager which manages access to the mobile station terminal through the CDMA communication network by an IOCP communication method, and processes user authentication of the mobile station terminal; A shortest base station selecting unit selecting a reference station closest to the mobile station terminal; And A geographic information system providing correction data for real-time coordinate correction based on Digi-PS and IOS communication, including a real-time correction value transmission unit for providing corresponding DGPS correction data in real time in response to a request of a mobile station. The mobile station terminal of claim 1, wherein the mobile station terminal receives GPS information from a mobile communication block and a satellite receiving DGPS correction data by connecting to a central server through a CDMA communication network according to an IOCP communication scheme, and correcting coordinates based on the DGPS correction data. Includes a GPS block to implement, The mobile communication unit block receives the coordinate information corrected from the GPS block, the geographic information system for providing correction data for real-time coordinate correction based on the digital PS and IOS communication to display the geographic information.