EP0335558A2
Expired / Lapsed
EP
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Radio communication system
Assignee: BAE Systems Electronics Ltd
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Filing: 1989-03-21
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Granted: —
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Expires: 2009-03-21
Abstract
Abstract A cellular or similar radio system measures the propagation time for signals to be transmitted between a mobile unit and at least two base stations, thereby obtaining two range measurements. This is used in a triangulation process to estimate the position of the mobile unit.
Inventors
- 👤 Daniel Vincent Mccaughan
- 👤 Boleslaw Marian Sosin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 03:27
CPC Classifications
H; H04; H04W; H04W64/00; G; G01; G01S; G01S13/00; G01S13/87; G01S13/878; G01S5/00; G01S5/02; G01S5/14
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
95 words
A radio communication system comprising a plurality of stations at known locations, hereinafter called "base stations", a movable station, and a facility for observing transmissions between the movable station and the base stations and for selecting, depending on the results of this observation, the best base station for the movable station to use for communication purposes; characterised by means for making measurements of the times for transmission of signals between the movable station and at least two base stations and means for deriving, from the measurements, an estimate of the location of the movable station.
Claim 2
Dependent Claim
95 words
A radio communication system comprising a plurality of stations at known locations, hereinafter called "base stations", a movable station, and a facility for observing transmissions between the movable station and the base stations and for selecting, depending on the results of this observation, the best base station for the movable station to use for communication purposes; characterised by means for making measurements of the times for transmission of signals between the movable station and at least two base stations and means for deriving, from the measurements, an estimate of the location of the movable station.
Claim 3
Dependent Claim
35 words
A system according to claim 1 comprising means for storing data representing a road map and means for correcting the said estimate by making an assumption that the movable station is located on a road.
Claim 4
Dependent Claim
51 words
A system according to claim 1 or 2 in which each measurement is of the round-trip time for a first signal to be sent in one direction from one station to another and for a second signal to be sent, in response to receipt of the first, in the reverse direction.
Claim 5
Dependent Claim
27 words
A system according to claim 3 comprising means for correcting each measurement to take into consideration a finite response time of the station receiving the first signal.
Claim 6
Dependent Claim
21 words
A system according to claim 1 and substantially as described with reference to the accompanying drawings and substantially as illustrated therein.
Claim 7
Dependent Claim
13 words
A movable station for use in a system according to any preceding claim.
Claim 8
Dependent Claim
13 words
A base station for use in a system according to any preceding claim.
References Cited (Backward Citations)
No citation records indexed.
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