EP0574009A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
DGPS positioning method, DGPS reference station and DGPS positioning apparatus for moving object
Assignee: MIWA SCIENCE LABORATORY Inc
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Filing: 1993-06-11
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Granted: —
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Expires: 2013-06-11
Abstract
Abstract In a differential GPS reference station (11) the accurate position of which is preknown, the position or pseudo range of the reference station is measured by a GPS stand-alone positioning unit on the basis of signals received from GPS satellites 13₁ through 13₄ and an error between the measured position or pseudo range of the reference station and its actual position or pseudo range is computed by a computer (14). A correction value for the error and the PRN number of each used satellite are broadcast, as reference station information, from RDS broadcasting equipment (12) while being multiplexed in an FM broadcast as an RDS signal. In a car (21), a car radio (22) receives the FM broadcast and extracts therefrom the reference station information and provides it to a computing part (23C). A GPS stand-alone positioning unit (23G) receives the signal from the GPS satellites of the same PRN number and performs GPS positioning, and the computing part (23C) corrects the measured value with the above-mentioned error and, if necessary, provides the corrected value to a navigation system (24).
Inventors
- 👤 Hirohide Miwa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 08:15
CPC Classifications
G; G01; G01S; G01S19/00; G01S19/01; G01S19/03; G01S19/07; G01S19/071; G01S19/38; G01S19/39; G01S19/40; G01S19/41
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
278 words
A differential GPS positioning method which receives signals from a plurality of GPS satellites and a signal from a reference station and determines the position of reception, said method comprising: (a) a step wherein a differential GPS reference station, the actual position of which is preknown, receives signals from at least three selected satellites and generates, on the basis of the received signal, reference station positioning information including measured position information corresponding to a measured position of said reference station defined by said satellites and actual position information corresponding to the actual position of said reference station; (b) a step wherein utilized satellite information indicating said selected satellites and said reference station positioning information in said step (a) are combined with each other and outputs as reference station information; (c) a step wherein said reference station information in said step (b) is broadcast by conventional public broadcasting means after being multiplexed with its radio wave; (d) a step wherein a moving object receives said radio wave and separates said utilized satellite information and said reference station positioning information from said reference station information in said step (c); (e) a step wherein signals from satellites indicated by said utilized satellite information separated in said step (d) are selectively received by a GPS stand-alone positioning means of said moving object and moving object position information corresponding to the position of said moving object is calculated on the basis of said received signals; and (f) a step of calculating the position of said moving object corrected on the basis of said moving object position information obtained in said step (e) and said reference station positioning information separated in said step (d).
Claim 2
Dependent Claim
137 words
The method of claim 1, wherein said step (a) includes a step of measuring the position of said reference station by said GPS stand-alone positioning means on the basis of orbit data received by said GPS stand-alone positioning means from said satellites, respectively, and a step of generating, as said reference station positioning information, the difference between the measured position of said reference station and said actual position of said reference station; said step (e) is a step of measuring the position of said moving object, as said moving object position information, by said GPS stand-alone positioning means of said moving object; and said step (f) is a step of obtaining said corrected position of said moving object by adding the measured position of said moving object with said difference separated as said reference station positioning information.
Claim 3
Dependent Claim
151 words
The method of claim 1, wherein said step (a) includes a step of measuring the position of said reference station on the basis of the orbit data received by said GPS stand-alone positioning means from said satellites, respectively, and a step of generating said measured position and said actual position information as said reference station positioning information; said step (e) is a step of measuring the position of said moving object, as said moving object position information, by said GPS stand-alone positioning means of said moving object; and said step (f) includes a step of calculating the difference between the measured position of said reference station separated as said reference station positioning information and the actual position of said reference station obtained from said actual position information, and a step of adding said difference to the measured position of said moving object to obtain said corrected position of said moving object.
Claim 4
Dependent Claim
216 words
The method of claim 1, wherein said step (a) includes a step of calculating pseudo ranges between said reference station and said respective satellites by said GPS stand-alone positioning means on the basis of the times needed for the signals from said satellites to reach said reference station, a step of calculating the positions of said satellites from the orbit data received therefrom and calculating the actual distances between said satellites and said reference station from said calculated positions of said satellites and said actual position of said reference station, and a step of generating the differences between said actual distances and said pseudo ranges, as said reference station positioning information, respectively; said step (e) is a step of calculating pseudo ranges between said moving object and said satellites and the positions of said satellites by said GPS stand-alone positioning means of said moving object, as said moving object position information, respectively; and said step (f) includes a step of obtaining corrected pseudo ranges by adding said differences, separated as said reference station information, to said pseudo ranges between said moving object and said satellites, respectively, and a step of calculating said corrected position of said moving object on the basis of the relationship between said calculated positions of said satellites and said corrected pseudo ranges.
Claim 5
Dependent Claim
192 words
The method of claim 1, wherein said step (a) includes a step of calculating pseudo ranges between said reference station and said satellites by GPS stand-alone positioning means on the basis of the times needed for the signals from said satellites to reach said reference station, and a step of generating sets of said pseudo ranges and said actual position information as said reference station positioning information; said step (e) is a step of calculating the positions of said satellites and the position of said moving object, as said moving object position information, respectively, by said GPS stand-alone positioning means of said moving object; and said step (f) includes a step of calculating the position of said reference station on the basis of the relationship between the respective pseudo ranges of said reference station separated as said reference station positioning information and the calculated positions of said satellites, and a step of obtaining the difference between the position of said moving object and the position of said reference station and adding said difference with the actual position obtained from said actual position information to obtain said corrected position of said moving object.
Claim 6
Dependent Claim
149 words
The method of claim 1, wherein said step (a) includes a step of measuring the position of said reference station by GPS stand-alone positioning means on the basis of orbit data received from said satellites and a step of generating a set of information corresponding to the position of said reference station and the said actual position of said reference station; said step (e) is a step of calculating the position of said moving object, as said moving object position information, by said GPS stand-alone positioning means of said moving object; and said step (f) includes a step of obtaining the difference between the position of said moving object and the position of said reference station separated as said reference station information, and a step of adding said difference with said actual position obtained from said actual position information to thereby obtain said corrected position of said moving object.
Claim 7
Dependent Claim
21 words
The method of claim 3, 5, or 6, wherein said actual position information is said actual position of said reference station.
Claim 8
Dependent Claim
64 words
The method of claim 3, 5, or 6, wherein said actual position information is identification information for identifying said reference station and said step (f) includes a step wherein the actual position of said reference station corresponding to said identification information is read out of a predetermined table indicating the relationship between the reference station indicated by said identification information and its actual position.
Claim 9
Dependent Claim
84 words
A differential GPS reference station whose accurate actual position is preknown, said station comprising: positioning means which receives signals from a plurality of satellites, performs GPS positioning and generates reference station positioning information corresponding to a measured position of said reference station; means for generating reference station information including said reference station positioning information obtained with said positioning means and utilized satellite information indicating said plurality of satellites used; and means for broadcasting said reference station information while multiplexing it with a public broadcast.
Claim 10
Dependent Claim
90 words
A differential GPS reference station whose accurate actual position is preknown, said reference station comprising: positioning means which receives signals from a plurality of satellites, performs GPS positioning and generates reference station positioning information corresponding to a measured position of said reference station; means for generating reference station information including said reference station positioning information obtained with said positioning means and utilized satellite information indicating said plurality of satellites used; and means for sending said reference station information to a broadcasting station wherein it is multiplexed with a public broadcast.
Claim 11
Dependent Claim
68 words
The reference station of claim 9 or 10, wherein said reference station positioning information includes an error of the pseudo range between said reference station and each of said plurality of satellites or a correction value for said pseudo range or a predictive value of said pseudo range after a predetermined time, and said utilized satellite information includes identification numbers and/or pseudo random codes of said utilized satellites.
Claim 12
Dependent Claim
44 words
The reference station of claim 9 or 10, wherein said reference station information includes an error between measured and actual positions of said reference station, or a correction value therefor, or a predictive value of said error or corrected value after a predetermined time.
Claim 13
Dependent Claim
68 words
The reference station of claim 9 or 10, wherein said reference station positioning information includes a pseudo range between said reference station and each of said utilized satellites or a predictive value of said pseudo range after a predetermined time and position information of said reference station, and said utilized satellite information includes at least one of identification numbers and pseudo random code numbers of said utilized satellites.
Claim 14
Dependent Claim
39 words
The reference station of claim 9 or 10, wherein said public broadcast is any one of a radio broadcast, a TV broadcast, a satellite broadcast, a weather broadcast and a weather map facsimile message and a disaster preventing broadcast.
Claim 15
Dependent Claim
34 words
The reference station of claim 9 or 10, wherein said public broadcast is a radio broadcast and said multiplexing system is of the RDS standard adopted by the Europe Broadcasting Union or similar standard.
Claim 16
Dependent Claim
76 words
A differential GPS positioning apparatus carried on a moving object or made in a portable form, said apparatus comprising: positioning means for performing differential GPS positioning; reference station information extracting means which receives a public broadcast from a differential GPS reference station and extracts reference station information multiplexed with said public broadcast; combining means for combining said extracted reference station information with data measured by said GPS positioning means to perform positioning of said moving object.
Claim 17
Dependent Claim
82 words
The apparatus of claim 16, wherein said reference station information is errors of pseudo ranges between said differential GPS reference station and said utilized satellites or correction values for said errors or their predictive values after a predetermined time, and said combining means is means whereby the pseudo ranges between said moving object and the same utilized satellites, measured by said positioning means of said moving object, are corrected with said reference station information to obtain the position of said moving object.
Claim 18
Dependent Claim
69 words
The apparatus of claim 16, wherein said reference station information is an error between measured and actual positions of said reference station or a correction value for said error, or its predictive value after a predetermined time, and said combining means is means whereby the measured position of said moving object, measured by said positioning means through use of said utilized satellite, is corrected with said reference station information.
Claim 19
Dependent Claim
109 words
The apparatus of claim 16, wherein said reference station information is a pseudo range between said reference station and each used satellite or its predictive value after a predetermined time and actual position information of said reference station, and said combining means which obtains the position of said reference station from said reference station information, obtains the difference between said position of said reference station thus obtained and the position of said moving object obtained by said positioning means and adds the relative position to the actual position of said reference position obtained from the position information of said reference station to obtain the position of said moving object.
Claim 20
Dependent Claim
93 words
The apparatus of claim 16, wherein said reference station information is a measured position of said reference station obtained by said reference station and the actual position information of said reference station, and said combining means is means which obtains the difference between said measured position of said reference station and the position of said moving object obtained by said positioning means and adds the relative position to the actual position of said reference station obtained from the position information of said reference station to thereby obtain the position of said moving object.
Claim 21
Independent Claim
80 words
The apparatus of any one of claims 16 through 20, wherein said reference station information extracting means is provided with extracting means which receives an FM radio broadcast and extracts reference station information multiplexed by a system of the RDS standard of the European Broadcasting Union or a similar system, and automatic channel switching means for automatically switching the tune of said FM radio broadcast to a channel of a normal field intensity when the received radio wave becomes weak.
Claim 22
Dependent Claim
35 words
The apparatus of claim 21, wherein said reference station information extracting means and said automatic channel switching means are included in an FM-RDS radio receiver and connected thereto or formed as a unitary structure therewith.
Claim 23
Dependent Claim
76 words
A radio receiver for a differential GPS positioning apparatus, comprising: automatically channel switching means for automatically switching a channel of a reduced field intensity to a channel of a normal field intensity; means for receiving a broadcasting wave having multiplexed therewith reference station information of a differential GPS reference station and for extracting said reference station information from said received broadcasting wave; and a terminal for providing therethrough said extracted reference station information to the outside.
Claim 24
Dependent Claim
76 words
A radio receiver for a differential GPS positioning apparatus, comprising: automatically switching means for automatically switching a channel of a reduced field intensity to a channel of a normal field intensity; means for receiving a broadcasting wave having multiplexed therewith reference station information of a differential GPS reference station and for extracting said reference station information from said received broadcasting wave; and means for outputting said extracted reference station information as a visible or audible form.
Claim 25
Dependent Claim
21 words
A navigation apparatus, characterized by the provision of said differential GPS positioning apparatus of any one of claims 16 through 20.
References Cited (Backward Citations)
No citation records indexed.
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