Position location using global positioning signals augmented by broadcast television signals

1. A method for determining the position of a user terminal, comprising:

receiving at the user terminal a broadcast television signal from a television signal transmitter;

determining a first pseudo-range between the user terminal and the television signal transmitter based on a known component of the broadcast television signal;

receiving at the user terminal a global positioning signal from a global positioning satellite; and

determining a second pseudo-range between the user terminal and the global positioning satellite based on the global positioning signal; and

wherein a position of the user terminal is determined based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

2. The method of claim 1 , further comprising:

determining a position of the user terminal based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

3. The method of claim 1 , wherein determining a position of the user terminal comprises:

adjusting the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

adjusting the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

determining the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

4. A method for determining the position of a user terminal, comprising:

receiving a first pseudo-range from the user terminal, the first pseudo-range determined between the user terminal and a television signal transmitter based on a known component of a broadcast television signal transmitted by the television signal transmitter;

receiving a second pseudo-range from the user terminal, the second pseudo-range determined between the user terminal and a global positioning satellite based on a global positioning signal transmitted by the global positioning satellite; and

determining a position of the user terminal based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

5. The method of claim 4 , wherein determining a position of the user terminal comprises:

adjusting the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

adjusting the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

determining the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

6. Computer-readable media embodying instructions executable by a computer to perform a method for determining the position of a user terminal, the method comprising:

determining a first pseudo-range between the user terminal and a television signal transmitter based on a known component of a broadcast television signal received at the user terminal from the television signal transmitter; and

determining a second pseudo-range between the user terminal and a global positioning satellite based on a global positioning signal received at the user terminal from the global positioning satellite; and

wherein a position of the user terminal is determined based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

7. The media of claim 6 , wherein the method further comprises:

determining the position of the user terminal based on the first and second pseudo-ranges, the location of the television signal transmitter, and the location of the global positioning satellite.

8. The media of claim 7 , wherein determining a position of the user terminal comprises:

adjusting the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

adjusting the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

determining the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

9. Computer-readable media embodying instructions executable by a computer to perform a method for determining the position of a user terminal, the method comprising:

receiving a first pseudo-range, the first pseudo-range determined between the user terminal and the television signal transmitter based on a known component of a broadcast television signal transmitted by the television signal transmitter;

receiving a second pseudo-range, the second pseudo-range determined between the user terminal and a global positioning satellite based on a global positioning signal transmitted by the global positioning satellite; and

determining a position of the user terminal based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

10. The media of claim 9 , wherein determining a position of the user terminal comprises:

adjusting the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

adjusting the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

determining the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

11. An apparatus for determining the position of a user terminal, comprising:

a receiver to receive at the user terminal a broadcast television signal from a television signal transmitter;

a processor to determine a first pseudo-range between the user terminal and the television signal transmitter based on a known component of the broadcast television signal;

wherein the receiver receives at the user terminal a global positioning signal from a global positioning satellite;

wherein the processor determines a second pseudo-range between the user terminal and the global positioning satellite based on the global positioning signal; and

wherein a position of the user terminal is determined based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

12. The apparatus of claim 11 :

wherein the processor determines the position of the user terminal based on the first and second pseudo-ranges, the location of the television signal transmitter, and the location of the global positioning satellite.

13. The apparatus of claim 12 , wherein:

the processor adjusts the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

the processor adjusts the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

the processor determines the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

14. An apparatus for determining the position of a user terminal, comprising:

a receiver to receive a first pseudo-range from the user terminal, the first pseudo-range determined between the user terminal and the television signal transmitter based on a known component of a broadcast television signal transmitted by the television signal transmitter;

wherein the receiver receives a second pseudo-range from the user terminal, the second pseudo-range determined between the user terminal and a global positioning satellite based on a global positioning signal transmitted by the global positioning satellite; and

a processor to determine a position of the user terminal based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

15. The apparatus of claim 14 , wherein:

the processor adjusts the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

the processor adjusts the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

the processor determines the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

16. The apparatus of claim 14 , further comprising:

an antenna to receive the broadcast television signal; and

wherein the antenna receives the global positioning signal.

17. An apparatus for determining the position of a user terminal, comprising:

receiving means for receiving at the user terminal a broadcast television signal from a television signal transmitter;

processing means for determining a first pseudo-range between the user terminal and the television signal transmitter based on a known component of the broadcast television signal;

wherein the receiving means receives at the user terminal a global positioning signal from a global positioning satellite;

wherein the processing means determines a second pseudo-range between the user terminal and the global positioning satellite based on the global positioning signal; and

wherein a position of the user terminal is determined based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

18. The apparatus of claim 17 :

wherein the processing means determines a position of the user terminal based on the first and second pseudo-ranges, the location of the television signal transmitter, and the location of the global positioning satellite.

19. The apparatus of claim 18 , wherein:

the processing means adjusts the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

the processing means adjusts the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

the processing means determines the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

20. An apparatus for determining the position of a user terminal, comprising:

receiving means for receiving a first pseudo-range from the user terminal, the first pseudo-range determined between the user terminal and a television signal transmitter based on a known component of a broadcast television signal transmitted by the television signal transmitter;

wherein the receiving means receives a second pseudo-range from the user terminal, the second pseudo-range determined between the user terminal and a global positioning satellite based on a global positioning signal transmitted by the global positioning satellite; and

processing means for determining a position of the user terminal based on the first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

21. The apparatus of claim 20 , wherein:

the processing means adjusts the first pseudo-range based on a difference between a transmitter clock at the television signal transmitter and a known time reference;

the processing means adjusts the second pseudo-range based on a relative radial velocity between the global positioning satellite and the user terminal; and

the processing means determines the position of the user terminal based on the adjusted first and second pseudo-ranges, a location of the television signal transmitter, and a location of the global positioning satellite.

22. The apparatus of claim 20 , further comprising:

antenna means for receiving the broadcast television signal; and

wherein the antenna means receives the global positioning signal.

23. The method of claim 1 , further comprising:

transmitting the first and second pseudoranges to a location server configured to determine the position of the user terminal based on the first and second pseudo-ranges, the location of the television signal transmitter, and the location of the global positioning satellite.

24. The method of claim 1 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and

an analog television signal.

25. The method of claim 4 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and

an analog television signal.

26. The media of claim 6 , wherein the method further comprises:

causing transmission of the first and second pseudoranges to a location server configured to determine a position of the user terminal based on the first and second pseudo-ranges, the location of the television signal transmitter, and the location of the global positioning satellite.

27. The media of claim 6 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and

an analog television signal.

28. The media of claim 9 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and

an analog television signal.

29. The apparatus of claim 11 , further comprising:

a transmitter to transmit the first and second pseudoranges to a location server configured to determine the position of the user terminal based on the first and second pseudo-ranges, the location of the television signal transmitter, and the location of the global positioning satellite.

30. The apparatus of claim 11 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and

an analog television signal.

31. The apparatus of claim 14 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and

an analog television signal.

32. The apparatus of claim 17 , further comprising:

transmitting means for transmitting the first and second pseudoranges to a location server configured to determine a position of the user terminal based on the first and second pseudo-ranges, the location of the television signal transmitter, and the location of the global positioning satellite.

33. The apparatus of claim 17 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and

an analog television signal.

34. The apparatus of claim 20 , wherein the broadcast television signal is selected from the group consisting of:

an American Television Standards Committee (ATSC) digital television signal;

a European Telecommunications Standards Institute (ETSI) Digital Video Broadcasting-Terrestrial (DVB-T) signal; and

a Japanese Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) signal; and an analog television signal.