DOPPLER-NULLING TRAVELING-WAVE ANTENNA RELAYS FOR HIGH-SPEED VEHICULAR COMMUNICATIONS

• US 20130069834A1
• Filed: 09/21/2011
• Published: 03/21/2013
• Est. Priority Date: 09/21/2011
• Status: Active Grant

• Current Assignee: Empire Technology Development LLC (Allied Inventors Management, LLC)
• Original Assignee: Empire Technology Development LLC (Allied Inventors Management, LLC)
• Inventors: Duerksen, Gary L.
• Granted Patent: US 8,948,690 B2
• Time in Patent Office: Days
• US Class Current: 343/711
• CPC Class Codes: H01Q 1/32 Adaptation for use in or on road or rail vehicles
• CPC Class Codes: H01Q 13/203 Leaky coaxial lines
• CPC Class Codes: H04B 7/01 Reducing phase shift
• CPC Class Codes: H04W 84/005 Moving wireless networks

Abstract

An antenna relay system for facilitating wireless communication between mobile terminals on a high-speed rail vehicle and stationary base stations with substantially reduced Doppler shift effects comprises matched traveling wave directional antennas mounted to a high-speed rail vehicle and positioned collinearly alongside the railway. Both antennas continually transmit and receive at a fixed angle relative to the motion of the train so as to circumvent the Doppler shift. The signal transmitted or received by the stationary antenna is conducted to a nearest node for communication with an access network.

Claims

1. A method for enhancing wireless communications in high-speed vehicles through Doppler-nulling traveling-wave antenna relays, the method comprising:

aggregating wireless traffic from a plurality of wireless communication devices at an access terminal on a moving vehicle; and

forwarding the wireless traffic to a wireless communication network through a pair of matched traveling-wave directional antennas, a first of the antennas positioned on the moving vehicle, a second of the antennas positioned along a path of the moving vehicle, wherein the second antenna is conductively coupled to one or more access nodes of the wireless communication network.

2. The method according to claim 1, wherein the first and second antennas are suitably designed to radiate continuously along their length in highly directional beams.

3. The method according to claim 2, wherein the first and second antennas are arranged to transmit and receive at a predefined angle relative to a motion of the moving vehicle.

4. The method according to claim 3, wherein the predefined angle deviates from 90 degrees between about 5 degrees and about 10 degrees.

5. The method according to claim 3, wherein the predefined angle is selected to correspond to a Doppler null.

6. The method according to claim 1, further comprising conducting signals received at the second antenna to a nearest access node of the wireless communication network.

7. The method according to claim 6, further comprising conducting signals received from the moving vehicle to an access node behind the moving vehicle.

8. The method according to claim 6, further comprising conducting signals transmitted to the moving vehicle to an access node in front of the moving vehicle.

9. The method according to claim 1, wherein the moving vehicle is a high-speed train, the first antenna is affixed to a train car, and the second antenna is positioned along a railroad.

10. The method according to claim 1, wherein at least one of the first and second antennas is one of:

a leaky coaxial cable antenna, a slot array antenna, a directional dipole array antenna, and/or a patch array antenna.

11. The method according to claim 10, further comprising positioning a first array of radiating elements of the first and second antennas at a periodic predefined distance such that a guided wave mode of the antennas couples into a single radiation mode.

12. The method according to claim 11, further comprising interleaving a second array of radiating elements along each antenna offset by about a quarter of the periodic predefined distance from the first array of radiating elements such that a stop band in the guided wave mode at wavelengths that couple into a broadside radiation mode is eliminated.

13. A wireless communication system enabling communication between high-speed vehicles and a terrestrial network through Doppler-nulling traveling-wave antenna relays, the system comprising:

an access terminal adapted to aggregate wireless traffic from a plurality of wireless communication devices on a moving vehicle and forward the aggregated wireless traffic to the terrestrial network through a pair of matched traveling-wave directional antennas;

a first traveling-wave directional antenna affixed to the moving vehicle; and

a second traveling-wave directional antenna positioned along a path of the moving vehicle, wherein the second antenna is conductively coupled to one or more access nodes of the wireless communication network.

14. The system according to claim 13, wherein the first and second antennas are suitably designed to radiate continuously along their length in highly directional beams.

15. The system according to claim 13, wherein the first and second antennas are arranged to transmit and receive at a predefined angle relative to a motion of the moving vehicle.

16. The system according to claim 15, wherein the predefined angle deviates from 90 degrees between about 5 degrees and about 10 degrees.

17. The system according to claim 15, wherein the predefined angle is selected to correspond to a Doppler null.

18. The system according to claim 13, wherein signals received at the second antenna are conducted to a nearest access node of the terrestrial network.

19. The system according to claim 18, wherein signals received from the moving vehicle are conducted to an access node behind the moving vehicle.

20. The system according to claim 18, wherein signals transmitted to the moving vehicle are conducted to an access node in front of the moving vehicle.

21. The system according to claim 13, wherein the moving vehicle is a high-speed train, the first antenna is affixed to a train car, and the second antenna is positioned along a railroad.

22. The system according to claim 13, wherein at least one of the first and second antennas is one of:

a leaky coaxial cable antenna, a slot array antenna, a directional dipole array antenna, and/or a patch array antenna.

23. The system according to claim 22, wherein a first array of radiating elements of the first and second antennas are positioned at a periodic predefined distance such that a guided wave mode of the antennas couples into a single radiation mode.

24. The system according to claim 23, wherein a second array of radiating elements are interleaved along each antenna offset by about a quarter of the periodic predefined distance from the first array of radiating elements such that a stop band in the guided wave mode at wavelengths that couple into a broadside radiation mode is eliminated.

25. A traveling-wave, directional antenna system for enabling wireless communication between high-speed vehicles and a terrestrial network, the system comprising:

a first traveling-wave directional antenna affixed to a moving vehicle adapted to receive aggregated wireless traffic from a plurality of wireless communication devices on the moving vehicle and forward the wireless traffic to the terrestrial network through a matching second traveling-wave antenna; and

the second traveling-wave directional antenna positioned along a path of the moving vehicle and conductively coupled to one or more access nodes of the wireless communication network.

26. The antenna system according to claim 25, wherein the first and second antennas are suitably designed to radiate continuously along their length in highly directional beams.

27. The antenna system according to claim 25, wherein the first and second antennas are arranged to transmit and receive at a predefined angle relative to a motion of the moving vehicle.

28. The antenna system according to claim 27, wherein the predefined angle deviates from 90 degrees between about 5 degrees and about 10 degrees.

29. The antenna system according to claim 27, wherein the predefined angle is selected to correspond to a Doppler null.

30. The antenna system according to claim 25, wherein the second antenna is adapted to conduct signals received from the first antenna to a nearest access node of the terrestrial network.

31. The antenna system according to claim 30, wherein the second antenna is adapted to conduct signals received from the moving vehicle to an access node behind the moving vehicle.

32. The antenna system according to claim 30, wherein the second antenna is adapted to conduct signals transmitted to the moving vehicle to an access node in front of the moving vehicle.

33. The antenna system according to claim 25, wherein the moving vehicle is a high-speed train, the first antenna is affixed to a train car, and the second antenna is positioned along a railroad.

34. The antenna system according to claim 25, wherein at least one of the first and second antennas is one of:

a leaky coaxial cable antenna, a slot array antenna, a directional dipole array antenna, and/or a patch array antenna.

35. The antenna system according to claim 34, wherein a first array of radiating elements of the first and second antennas are positioned at a periodic predefined distance such that a guided wave mode of the antennas couples into a single radiation mode.

36. The antenna system according to claim 35, wherein a second array of radiating elements are interleaved along each antenna offset by about a quarter of the periodic predefined distance from the first array of radiating elements such that a stop band in the guided wave mode at wavelengths that couple into a broadside radiation mode is eliminated.