Correlation of flight track data with other data sources

• US 7,248,219 B2
• Filed: 08/22/2005
• Issued: 07/24/2007
• Est. Priority Date: 02/29/2000
• Status: Expired due to Term

• Current Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Original Assignee: ERA Systems Corporation (General Dynamics Corporation)
• Inventors: Smith, Alexander E., Cohen, Bennett
• Primary Examiner(s): PHAN, DAO LINDA
• Application Number:
  US11/209,030
• Publication Number:
  US 20070069950A1
• Time in Patent Office: 701 Days
• Field of Search: 342/455, 342/456, 342/463, 342/465, 701/14, 701/15, 701/120
• US Class Current: 342/456
• CPC Class Codes: G01S 13/781 Secondary Surveillance Radar [SSR] in general
• CPC Class Codes: G01S 13/86 Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
• CPC Class Codes: G01S 5/0284 Relative positioning
• 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
• CPC Class Codes: G08G 5/0013 with a ground station
• CPC Class Codes: G08G 5/006 in accordance with predefined flight zones, e.g. to avoid prohibited zones
• CPC Class Codes: G08G 5/0082 for monitoring traffic from a ground station radar or analogous systems specially adapted for traffic control G01S13/91

Abstract

A method of triangulating aircraft transponder signals using a number of receivers connected to a central station over communication links includes applying at least one logic rule at each receiver to incoming transponder signals to filter redundant transponder signals, time-stamping filtered transponder signals, and transmitting time-stamped transponder signals to the central station. Logic rules include at least one of altitude filtering, Mode S, Mode A/C code filtering, and change filtering. Replies are accepted when a change in state is indicated, such that the only those replies indicating a change in state are time-stamped and sent to the central server.

Claims

1. A method of triangulating aircraft transponder signals using a number of radio receivers connected to a central station over communication links, said method comprising the steps of:

applying at least one logic rule at each radio receiver to incoming aircraft transponder signals to filter redundant transponder signals,

time-stamping filtered transponder signals, and

transmitting time-stamped transponder signals to the central station.

2. The method of claim 1, wherein the logic rules include at least one of altitude filtering, Mode S, Mode A/C code filtering, and change filtering.

3. The method of claim 1, wherein replies are accepted when a change in state is indicated, such that the only those replies indicating a change in state are time-stamped and sent to the central server.

4. A system for triangulating aircraft transponder signals comprising:

a central station for receiving time-stamped signals from a plurality of radio receivers;

a plurality of radio receivers connected to the central station over communication links, each of said radio receivers comprising;

means for applying at least one logic rule at each receiver to incoming aircraft

transponder signals to filter redundant aircraft transponder signals,

means for time-stamping filtered aircraft transponder signals, and

means for transmitting time-stamped aircraft transponder signals to the central station.

5. The system of claim 4, wherein the logic rules include at least one of altitude filtering, Mode S, Mode A/C code filtering, and change filtering.

6. The system of claim 4, wherein replies are accepted when a change in state is indicated, such that the only those replies indicating a change in state are time-stamped and sent to the central server.