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Electronic device and method for blocking cellular communication

  • US 6,456,822 B1
  • Filed: 11/25/1997
  • Issued: 09/24/2002
  • Est. Priority Date: 11/26/1996
  • Status: Expired due to Term
First Claim
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1. A method for prevention of cellular telephone calls in a cellular communication system within a given area, said method comprising:

  • determining a plurality of control frequency existing within the area for establishing cellular telephone calls, said at least one control frequency containing information thereon, said information being transmitted as coded signals and commands; and

    generating an interference signal which interferes with said at least one control frequency by preventing decoding of said signals and commands, said interference signal preventing generation of handshake signals in the system, to prevent establishment of a cellular phone call with a portable cellular telephone, wherein said interference signal is generated continuously on said at least one control frequency; and

    wherein generating comprises mixing said determined control frequency with a predetermined frequency to develop a phase modulated signal, wherein the interference signal blocks decoding of a forward control channel signal by introducing phase noise in said portable cellular telephone.

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