Pseudolite Positioning System

• US 20130201057A1
• Filed: 04/18/2011
• Published: 08/08/2013
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Kubrak, Damien
• Granted Patent: US 9,423,502 B2
• Time in Patent Office: Days
• US Class Current: 342/357.48
• CPC Class Codes: G01S 19/11 wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters

Abstract

A positioning system comprises a set of pseudolites distributed in a confined area, said pseudolites transmitting positioning signals characterized by their time desynchronization and their apparent Doppler frequency, said time desynchronization and/or said apparent Doppler frequency of the positioning signals transmitted by the pseudolites being configured so that there is no ambiguity concerning the location of the correlation peaks P1, P2, P3, P4, P5 in the matrix of ambiguities defined by the delay and the apparent Doppler frequency of the positioning signals acquired by the receiver.

Claims

1. A system for positioning an object in an area of interest having a confined area, said system comprising a set of pseudolites distributed in the confined area, said pseudolites having a spreading code corresponding to the spreading code of a satellite belonging to a constellation of satellites of a satellite navigation system, and transmitting positioning signals characterized by their time desynchronization and their apparent Doppler frequency, and said object comprising a receiver capable of acquiring the positioning signals, said system further comprising:

a server comprising means for configuring said time desynchronization and/or said apparent Doppler frequency of the positioning signals transmitted by the pseudolites so that there is no ambiguity concerning the location of the correlation peaks in the matrix of ambiguities defined by the delay and the apparent Doppler frequency of the positioning signals acquired by the receiver.

2. The system as claimed in claim 1, further comprising means for controlling the power of the positioning signals transmitted by the pseudolites.

3. The system as claimed in claim 1, wherein the time desynchronization and the apparent Doppler frequency of the positioning signals transmitted by the pseudolites are first programmed at each pseudolite.

4. The system as claimed in claim 1, wherein all the pseudolites have the same spreading code.

5. The system as claimed in claim 4, the receiver comprising a number of channels greater than 1 for the search and acquisition of positioning signals, characterized in that said receiver can dedicate only one channel to the search for positioning signals transmitted by the pseudolites.

6. The system as claimed in claim 1, wherein the positioning signals transmitted by the pseudolites have frequencies belonging to a range of frequencies with no intersection with the range of frequencies used to transmit positioning signals by the satellites belonging to the constellation of satellites of the satellite navigation system in question.