Apparatus for multilateration and method

• US 20080042902A1
• Filed: 05/23/2007
• Published: 02/21/2008
• Est. Priority Date: 07/03/2006
• Status: Active Grant

• Current Assignee: ROKE Manor Research Limited (Chemring Group PLC)
• Original Assignee: ROKE Manor Research Limited (Chemring Group PLC)
• Inventors: Quilter, Timothy, Brandwood, David
• Granted Patent: US 7,830,308 B2
• Time in Patent Office: Days
• US Class Current: 342/465
• CPC Class Codes: G01S 13/781 Secondary Surveillance Radar [SSR] in general
• CPC Class Codes: G01S 5/0081 Transmission between base stations
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence

Abstract

To cater for the positioning of an aircraft in a boundary zone between two adjacent multilateration systems, the controller (14) in one system receives Time Difference of Arrival data provided by the controller (15) in the second system. The controller (15) derives the TDoA data from time of arrival data provided by its receiver stations (9-13). By furnishing TDoA data the timings of the two systems do not need to be synchronised. The controller (14) uses the TDoA data and also time of arrival data from its local receiver stations (4-8) to perform a multilateration to determine the location of the aircraft (16).

Claims

1. A multilateration system comprising a controller for receiving data concerning a signal transmitted from an object to be positioned from a first set of receiving stations and data concerning the signal from a second set of receiver stations which controller performing a multilateration process on the data to determine the location of the object.

2. A multilateration system as claimed in claim 1 wherein the first set of receiving stations provides data to a first controller for performing a multilateration process on at least the data and a second controller for performing a multilateration process on at least the data from the second set of receiver stations.

3. A multilateration system as claimed in claim 1, comprising a controller for receiving data concerning receipt of a signal transmitted from an object to be positioned from a first set of receiving stations and time difference of arrival data from a second set of receiver stations also receiving the signal from the object which controller performing a multilateration process on the data to determine the location of the object.

4. A multilateration system as claimed in claim 3 wherein the data concerning the receipt of the signal is time of arrival data or time difference of arrival data.

5. A multilateration system as claimed in claim 3, wherein the time difference of arrival data from the second set of receiver stations is derived from time of arrival data.

6. A multilateration system as claimed in claim 1 wherein the time difference of arrival data derived from time of arrival data from a second set of receiver stations is derived by a second controller.

7. A multilateration system as claimed in claim 1, comprising at least a first, second and third controller wherein the first and second controllers transmit at least one of the time difference of arrival data and time of arrival data concerning the received signals to the third controller which performs a multilateration on the data to locate an object.

8. A multilateration system as claimed in claim 1, further comprising a communications link between the controllers for transmission of the time difference of arrival data.

9. A multilateration system as claimed in claim 8 wherein at least one of the controllers includes one of a transmitter or receiver station coupled to the communications link and the other of the at least one of the controllers includes the other of the transmitter or receiver station.

13. A method as claimed in claim 1, wherein the controller determining that the object has approached a particular zone adopts a master role and recruits a second controller receiving data from the second set of receiver stations.

10. A method for locating the position of an object transmitting a radio signal comprising:

receiving data concerning receipt of the signal from a first set of receiver stations;

receiving Time Difference of Arrival data from a second set of receiver stations;

performing a multilateration process on the data and the Time Difference of Arrival data to derive the location of the object.

11. A method as claimed in claim 10 wherein the data concerning receipt of the signal is time of arrival data.

12. A method as claimed in claim 11, comprising the preliminary step of determining the approach of the object to a particular zone before carrying out the method.

14. A method as claimed in claim 11 wherein the second controller determines Time Difference of Arrival data from time of arrival data provided by the second set of receiver stations and transmits the Time Difference of Arrival data to the master controller.

15. (canceled)