SURFACE VEHICLE FLEET COMMAND AND CONTROL SYSTEM

• US 3,646,580 A
• Filed: 07/18/1969
• Issued: 02/29/1972
• Est. Priority Date: 07/18/1969
• Status: Expired due to Term

• Current Assignee: Joseph J. Oliver, Robert K. Kaye, Roger L. Fuller, William H. Rood
• Original Assignee: Joseph J. Oliver, Robert K. Kaye, Roger L. Fuller, William H. Rood
• Inventors: Fuller, Roger L., Kaye, Robert K., Oliver, Joseph J., Rood, William H.
• Primary Examiner(s): Safourek, Benedict V.
• Application Number:
  US04/842,885
• Time in Patent Office: 956 Days
• Field of Search: 343/6,6.5,6.5LC,6.8,6.8LC,112,112TC,13,14 325/1,3,5,6,51,53,54,57,58 340/22,23,24,52,53,62
• US Class Current: 455/524
• CPC Class Codes: G08G 1/127 to a central station ; Indicators in a central station
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles

Abstract

A system for communicating with and locating mobile surface vehicles in a high multipath signal clutter environment such as an urban center. This system seeks to take advantage of the scattering of the CW wave in urban areas for both communication and ranging where line of sight radiation techniques may not properly function. A plurality of remote relay stations are located at fixed points throughout the urban area. Each station receives and transmits wireless coded digital data and tone burst signals, the tone burst signals being used for phase ranging. Additionally, each of the surface vehicles is equipped with a transponder. The vehicle transponder is responsive only to a radio signal having a formatted message. This includes the vehicle identification code and a ranging tone suitably impressed thereon. The formatted signal is transmitted from one of the relay stations and picked up by a preselected number of other relay stations as well as the vehicle transponder. The transponder in turn generates a reply signal containing message data and a tone burst signal in phase with the original transmitted signal.

Claims

1. A vehicle location system comprising:

a plurality of remote relay stations, each station being capable of transmission of a predetermined relay signal and of signal reception;

a plurality of transponders, each located at a corresponding vehicle, each transponder being operable upon receipt of one of said predetermined signals from at least one of said relay stations, said predetermined signal having a ranging tone impressed thereon;

means at each of said plurality of transponders responsive only to a corresponding vehicle identification code in said predetermined signal for generating a reply signal within a predetermined time after initial receipt of said predetermined signal;

means at said plurality of remote relay stations for receiving said reply signal; and

means at each of said plurality of remote relay stations for measuring the phase difference between the original ranging tone and the reply signal.

2. A vehicle location system in accordance with claim 1 further comprising:

means for transmitting said phase measurements from said remote relay station to a central location; and

means at said central location including computing means for determining the location of said plurality of vehicles.

3. In combination:

at least one transmitter for transmitting interrogating signals having at least coded interrogation portions;

a plurality of transponders located in vehicles at spaced locations responsive to different identification codes of said interrogation portions for receiving said interrogating signals and for transmitting a composite reply signal, said reply signal comprising an identification portion and a tone signal; and

a plurality of receiving means at a plurality of different predetermined locations for receiving said reply signal and for measuring the phase of said tone signal with respect to a phase reference signal.

4. A combination in accordance with claim 3 further comprising:

means for processing data including at least said phase measurements for determining the location of said vehicles.

5. A combination in accordance with claim 4 wherein said vehicles comprise a fleet of mobile surface vehicles.

6. A combination in accordance with claim 4 wherein said identification code in the interrogation portion of said composite transmitted signal is received by said plurality of transponders, such that only one of said transponders is responsive to said identification code;

and means at said one transponder for generating a coded reply signal within a predetermined time after initial receipt of said transmitted signal.

7. A combination in accordance with claim 6 wherein said transmitted composite signal is an omnidirectional signal.