RADIO FREQUENCY POSITIONING SYSTEM FOR VEHICLES

• US 20110285593A1
• Filed: 02/02/2010
• Published: 11/24/2011
• Est. Priority Date: 02/02/2009
• Status: Active Grant

• Current Assignee: Elettric 80 S.P.A.
• Original Assignee: Elettric 80 S.P.A.
• Inventors: Cavirani, Vittorio, Marcaccioli, Luca, Trotta, Francesco, Vincenti Gatti, Roberto, Manzini, Franco, Di Terlizzi, Domenico
• Granted Patent: US 8,643,536 B2
• Time in Patent Office: Days
• US Class Current: 342/457
• CPC Class Codes: G01S 13/756 using a signal generator for modifying the reflectivity of the reflector G01S13/758 takes precedence
• CPC Class Codes: G01S 13/767 Responders; Transponders teaching or practice apparatus for gun-aiming or gun-laying using reflecting targets or active targets F41G3/26
• CPC Class Codes: G01S 13/825 with exchange of information between interrogator and responder
• CPC Class Codes: G01S 13/876 Combination of several spaced transponders or reflectors of known location for determining the position of a receiver G01S13/874 takes precedence
• CPC Class Codes: G01S 7/024 using polarisation effects in waveguides H01P1/165; for aerials H01Q, e.g. H01Q15/22, H01Q15/24, H01Q19/195
• CPC Class Codes: G01S 7/35 Details of non-pulse systems
• CPC Class Codes: H01Q 21/065 Patch antenna array
• CPC Class Codes: H01Q 3/46 Active lenses or reflecting arrays

Abstract

A positioning system for radio frequency devices includes a two-way radio antenna, for vehicles, having a transmitting and a receiving element. Reference antennas have retro-directive arrays which can shape the signal beams in elevation; polarize transmission and reception signals according to a circular or a linear polarization, the polarized transmission retro-directively reflecting signals having the same polarization as the incident ones in the case of circular polarisation, or retro-directively reflecting signals having orthogonal polarisation in the case of linear polarisation. An encoder is included for transmitting an identification code of the reference antenna. A controller processes the spatial and temporal data resulting from communication through the radio waves transmitted and received by the vehicle antennas and reflected by the reference antennas. The controller calculates the distance of the vehicle from the reference antennas that have reflected the signal transmitted by the antennas.

Claims

1-17. -17. (canceled)

18. A positioning system for vehicles in an area, said system operating with radio frequency devices based on Ultra-Wide-Band or Frequency-Modulated Continuous Wave, comprising:

a two-way radio antenna, associated with each vehicle, including a transmitting element and a receiving element;

a plurality of reference antennas located in known predetermined positions within the area, said reference antennas having retro-directive arrays, said retro-directive arrays including;

means for shaping the signal beams in elevation;

means for polarising transmission and reception signals according to a circular polarisation or to a linear polarisation, said means for polarising reflecting in a retro-directive manner signals having the same polarisation as the incident ones in case of circular polarisation, or reflecting in a retro-directive manner signals having orthogonal polarisation in case of linear polarisation;

encoding means, or signal processing means, for transmitting an identification code of the reference antenna;

control means for processing the spatial and temporal data resulting from the communication through the radio waves transmitted and received by the vehicle antennas and reflected by said reference antennas, said control means calculating the distance of the vehicle from the reference antennas that have reflected the signal transmitted by the antennas.

19. The positioning system for vehicles according to claim 18, wherein the transmitting element and the receiving element of the two-way radio antenna comprise sector directive antennas formed by a plurality of radiating panels with directive transmission and reception arranged and connected for carrying out a 360 degree scanning.

Attorney Docket:

374-106

20. The positioning system for vehicles according to claim 19, wherein the transmitting element and the receiving element of the two-way radio antenna comprise means for shaping the signal beams.

21. The positioning system for vehicles according to claim 20, wherein said means for shaping the signal beams shape the beam of the elevation signal, said means for shaping allowing the propagation of the electromagnetic waves according to predetermined directions and attenuating electromagnetic waves in others, so as to attenuate the signals coming from unexpected directions and/or being non-congruent with a starting or arrival signal.

22. The positioning system for vehicles according to claim 21, wherein the transmitting element and the receiving element of the two-way radio antenna comprise means for polarising the signals.

23. The positioning system for vehicles according to claim 22, wherein the transmitting element and the receiving element of the two-way radio antenna comprise means for polarising the signals in a circular manner, such that said two-way radio antenna is of the type with circular polarisation.

25. The positioning system for vehicles according to claim 22, wherein the transmitting element and the receiving element of the two-way radio antenna, when the active retro-directive arrays include means for polarising transmission and reception signals according to a linear polarisation, comprise means for polarising the signals in a linear manner, such that said two-way radio antenna is of the type with linear polarisation.

26. The positioning system for vehicles according to claim 25, wherein the active retro-directive arrays of the reference antennas reflect, in a retro-directive manner, signals having polarisation orthogonal to that of the incident signals.

27. The positioning system for vehicles according to claim 26, wherein the transmitting element and the receiving element are respectively suitable for transmitting and receiving signals having polarisation orthogonal relative to one another.

28. The positioning system for vehicles according to claim 18, wherein said encoding means comprise at least one element with variable capacity, positioned on at least one of the paths connecting said retro-directive arrays, suitable for varying its capacity according to a predetermined law, so as to multiply the signal reflected by said reference antenna according to said law and so as to identify said reference antenna.

24. The positioning system for vehicles according to claim 24, wherein the transmitting element and the receiving element respectively transmit and receive signals having the same polarisation.

29. A two-way radio antenna for a positioning system for vehicles, the antenna being associated with each vehicle and comprising:

a transmitting element and a receiving element, each transmitting and receiving element having sector directive antennas formed by a plurality of radiating panels, with directive transmission and reception arranged and connected for carrying out a 360 degree scanning.