Property protection method relating to watercraft

• US 5,818,335 A
• Filed: 08/21/1996
• Issued: 10/06/1998
• Est. Priority Date: 10/11/1993
• Status: Expired due to Fees

• Current Assignee: Hartmut Rinsch
• Original Assignee: Hartmut Rinsch
• Inventors: Pannen, Torsten, Rinsch, Hartmut
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US08/628,671
• Time in Patent Office: 776 Days
• Field of Search: 340/539, 340/566, 340/932.2, 340/984, 340/825.54, 340/825.69, 340/825.72, 340/825.31, 340/825.32, 340/825.27
• US Class Current: 340/10.33
• CPC Class Codes: B60R 2325/304 Boats
• CPC Class Codes: B60R 25/1012 Zone surveillance means, e.g. parking lots, truck depots
• CPC Class Codes: B63B 2017/0009 Methods or devices specially adapted for preventing theft, or unauthorized use of vessels, or parts or accessories thereof, other than by using locks
• CPC Class Codes: B63J 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A process is disclosed for protecting watercraft against theft in an area delimited in space, for example a harbor, using a stationary transmitting/receiving unit and an on-board transmitting/receiving unit. When interrogated by the stationary unit, the on-board unit emits a characteristic identification signal. The identification signal contains a basic key that identifies the watercraft and the identification signals of all watercraft in the harbor are stored in a central computer. To legitimize use of the watercraft, a legitimization key is input into a central computer before departure. The central computer ascertains whether the use of the watercraft is legitimate based on the interrogation carried out by the stationary transmitting/receiving unit and, if required, triggers an alarm and information program.

Claims

1. A process to protect the ownership of watercraft that lie in a spatially limited area, said process comprising the steps of

positioning a stationary transmitting/receiving unit near said area for interrogating craft entering and leaving said area;

positioning a mobile transmitting/receiving unit on board at least one craft in said area which, when interrogated by the stationary unit, transmits a coded identification signal for the corresponding craft whose code contains a basic code identifying the craft and an additional changeable code signifying authorized use of the corresponding craft;

connecting a central computer to the stationary unit to receive and store identification signal codes for all craft lying in said area;

comparing the code identification signal in the coded identification signal transmitted by said mobile unit with the identification signal codes stored in the computer and

1) when the stationary unit receives an identification signal code that is the same as an identification signal code stored in the computer, it sends back to the mobile unit, an additional code which corresponds to a first predetermined value, and

2) when the stationary unit receives an identification signal code that is not the same as any identification signal code stored in the computer, it sends back to the mobile unit, an additional code which corresponds to a second predetermined value, and

storing in the mobile unit, the identification code sent back by the stationary unit.

2. The process defined in claim 1 and including the step of providing means in the central computer only for changing the additional code in the coded identification signal transmitted to said mobile unit.

3. The process according to claims 1 or 2 including the steps of

comparing in the central computer, the basic code in the coded identification signal transmitted by said mobile unit with the basic codes stored in the computer, and

triggering an alarm if the additional code in said coded identification signal does not correspond to said first predetermined value.

4. The process according to claim 1 or 2 including the step of storing in the computer an identification signal code received by the stationary unit from the mobile unit when the stationary unit receives an identification signal code whose basic code is not the same as any of the basic codes stored in the computer.

5. The process according to claim 1 or 2 including the additional step of arranging said stationary unit so that at least one sector of its electromagnetic radiation pattern extends along the border of said spatially limited area.