Systems and methods employing active TCAS to enhance situational awareness

1. A method comprising:

transmitting a Mode S interrogation;

receiving a response from an aircraft that has received the Mode S interrogation;

determining a range to the aircraft based on a time period between transmitting the Mode S interrogation and receiving the response;

requesting information from one or more data sources, wherein the requesting includes specifying that the information should only be provided by the one or more data sources if the aircraft is within a predetermined volume;

receiving the information from the one or more data sources; and

determining at least one of a bearing to the aircraft and a position of the aircraft using the determined range and the information from the one or more data sources.

2. The method of claim 1 , wherein the information from the one or more data sources includes at least one of:

a range between the aircraft and one or more of the data sources;

a bearing to the aircraft from one or more of the data sources;

a position of one or more of the data sources;

a velocity of one or more of the data sources; and

an identifier for one or more of the data sources.

3. The method of claim 1 , further comprising displaying the position of the aircraft in conjunction with a map of a geographical region through a Cockpit Display of Traffic Information (CDTI).

4. The method of claim 1 , wherein the predetermined volume is bounded by at least one dimension measured from at least one of:

a distance from a vehicle;

a distance from the one or more data sources;

a distance from a fixed geographical location; and

combinations thereof.

5. The method of claim 1 , wherein determining the position of the aircraft is further based on the determined bearing.

6. The method of claim 1 , wherein determining at least one of the bearing to the aircraft and the position of the aircraft is based on one or more geographical features.

7. The method of claim 1 , further comprising:

transmitting a second Mode S interrogation;

receiving a second response from the aircraft that has received the second Mode S interrogation;

determining a second range to the aircraft based on a second time period between transmitting the second Mode S interrogation and receiving the second response; and

determining at least one of a velocity direction of the aircraft and a velocity magnitude of the aircraft based on the determined range and the second determined range.

8. A system comprising:

a processor;

a Mode S transceiver;

a data transceiver; and

a memory coupled to the processor and storing instructions that, when executed by the processor, cause the processor to:

transmit a Mode S interrogation using the Mode S transceiver;

receive a response through the Mode S transceiver from an aircraft that has received the Mode S interrogation;

determine a range to the aircraft based on a time period between transmitting the Mode S interrogation and receiving the response;

request information from one or more data sources, wherein the requesting includes specifying that the information should only be provided by the one or more data sources if the aircraft is within a predetermined volume;

receive the information from the one or more data sources through the data transceiver; and

determine at least one of a bearing to the aircraft and a position of the aircraft using the determined range and the information from the one or more data sources.

9. The system of claim 8 , further comprising a user interface, wherein the memory further stores instructions that, when executed by the processor, cause the processor to describe the position of the aircraft to a user through the user interface.

10. The system of claim 9 , wherein the user interface includes a Cockpit Display of Traffic Information (CDTI) and the position of the aircraft is displayed in conjunction with a map of a geographical region.

11. The system of claim 9 , wherein the memory further stores instructions that, when executed by the processor, cause the processor to:

determine whether the aircraft poses a threat to a vehicle coupled to the system; and

issue an alert to the user through the user interface when it is determined that the aircraft poses a threat to the vehicle.

12. The system of claim 8 , wherein the memory further stores instructions that, when executed by the processor, cause the processor to:

transmit a second Mode S interrogation using the Mode S transceiver;

receive a second response through the Mode S transceiver from the aircraft that has received the second Mode S interrogation;

determine a second range to the aircraft based on a time period between transmitting the second Mode S interrogation and receiving the second response;

determine at least one of a velocity direction of the aircraft and a velocity magnitude of the aircraft based on the determined range and the second determined range.