Location-sensitive decryption of an encrypted message
US5640452A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 28, 1995 |
| Grant date | Jun 17, 1997 |
| Priority date | — |
| Expiry date | Apr 28, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/165
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system for assuring the location integrity of a decryption chip used to receive and decrypt encrypted signals ES received from an encrypted signal source. The decryption chip operates in association with a licensed signal receiver and is licensed for use at a selected site or location L.sub.i and is positioned adjacent to a Satellite Positioning System (SATPS) antenna and receiver/processor that determine the present location L of this antenna. If the SATPS-determined location L is within a region R(L.sub.i ;d.sub.i), centered at the location L.sub.i and having a selected diameter d.sub.i, and if the signal ES is associated with a channel that is authorized for reception by this signal receiver, the deception chip is enabled, and the signal ES is decrypted for audible or visual display on the signal receiver. Otherwise, the decryption chip does not decrypt the incoming signal ES. The licensed site location L.sub.i can be changed and the group of channels for which signal receipt and decryption is authorized can be changed. This system can operate on encrypted television signals and other similar signals. The SATPS may be a Global Positioning System (GPS) or a Global Orbiting Navi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.