Real time self differential global positioning system and method for a moving station in a local area, and terminal global positioning system using the same

• US 20030083817A1
• Filed: 04/25/2002
• Published: 05/01/2003
• Est. Priority Date: 10/29/2001
• Status: Active Grant

• Current Assignee: Total Soft Bank Ltd.
• Original Assignee: Total Soft Bank Ltd.
• Inventors: Yi, Dong Hyuk
• Granted Patent: US 6,704,652 B2
• Time in Patent Office: Days
• US Class Current: 701/215
• CPC Class Codes: G01S 19/071 DGPS corrections

Abstract

A real-time self Differential Global Positioning System (DGPS) is developed for positioning a moving station in a local area. This DGPS system enables not only to minimize the error ranges without any additional expansive transmitting-receiving equipment, but also to calculate an accurate correcting value through a DGPS receiver. A method of the real-time self DGPS system comprises the steps of: (1) receiving a GPS signal of moving station contained data of satellite time and pre-measured moving station position, (2) calculating a correcting value from the moving station, (3) positioning the accurate moving station according to the correcting value and the GPS signal of moving station.

Claims

1. A real time self Differential Global Positioning System (DGPS) for a moving station being operated under a client circumstance with a wireless LAN network and server in a local area, said DGPS system comprises:

a private reference station (10) being pre-measured its'"'"' position through accurate measurement, said private reference station (10) including a reference station GPS receiver (11) for detecting position via satellites (20˜

23),

a moving station (30) including a moving station GPS receiver (31) for detecting position via satellites, and a first wireless modem (32) for transmitting RGPS signals contained a position data and satellite time data from said moving station GPS receiver (31),

a central control unit (40) including a TGPS receiver (41), a central control server (42) and a second wireless modem (43),

said second wireless modem (43) communicating with said first wireless modem (32) in a short distance,

said TGPS receiver (41) being interfaced with said reference station GPS receiver (11), received said RGPS signals from said reference station, calculated correction data (X′

0, Y′

0) from the received data, and transmitted said calculated correction data to said central control server (42), and

said central control server (42) being interfaced with said second wireless modem (43), received said RGPS signals from said moving station, and calculated real position of said moving station by correcting error from the received RGPS signals of position data of moving station.

2. A real-time self DGPS as claimed of claim 1, said local area is defined within a range of several kilometers, and said position data enabling to transform a position coordinating value in the local area.

3. A terminal Global Positioning System (TGPS) being adopted a real-time self DGPS system in a local area, the TGPS system comprises:

a private reference station (10) being pre-measured its'"'"' position through accurate measurement, said private reference station (10) including a reference station GPS receiver (11) for detecting position via satellites (20˜

23),

a moving station (30) including a moving station GPS receiver (31) for detecting position via satellites, and a first wireless modem (32) for transmitting RGPS signals contained a position data and satellite time data from said moving station GPS receiver (31),

a central control unit (40) including a TGPS receiver (41), a central control server (42) and a second wireless modem (43),

said second wireless modem (43) communicating with said first wireless modem (32) in a short distance,

said TGPS receiver (41) being interfaced with said reference station GPS receiver (11), received said RGPS signals from said reference station, calculated correction data (X′

0, Y′

0) from the received data, and transmitted said calculated correction data to said central control server (42), and

said central control server (42) being interfaced with said second wireless modem (43), received said RGPS signals from said moving station, and calculated real position of said moving station by correcting error from the received RGPS signals of position data of moving station, and

a job control data and position data able to codify a code comprising a string with a header and a separator (-).

4. A method of real time self Differential Global Positioning System (DGPS) in a local area comprises the processing steps of:

receiving a moving station GPS signal (Mgps_0) at a central control server (42), said moving station GPS signal (Mgps_0) being contained data of satellite time (T0) and moving station position (Xm0, Ym0) which are measured via a moving station GPS receiver (MGPS) (31) at a specific position and time, transmitting said data of satellite time (T0) of moving station GPS signal to a TGPS receiver (41),

receiving reference station GPS signals (Rgps_−

2, Rgps_−

1, Rgps_0, Rgps_1, Rgps_2) at the TGPS server (41), said reference station GPS signals being contained satellite time (T0) data and position data (Xr, Yr) which are measured via a reference station GPS (RGPS) receiver (11) of private reference station (10) at near to said satellite time (T0),

selecting a position data (Xr0, Yr0) of reference station GPS signal being corresponded to said satellite time (T0),

calculating a correcting value (X′

0, Y′

0) according to said selected reference station GPS signal (Rgps_0) and stored actual position data (Xs, Ys) of reference station, and

calculating an error corrected real position (Xcm0, Ycm0) of said moving station according to said correcting value and position data of moving station.