Interdiction method and apparatus with constant blanking and var

Details Interdiction method and apparatus with constant blanking and var Interdiction method and apparatus with constant blanking and var

1992-06-10

1994-02-22

Swann, Tod R.

Cryptography

Cryptanalysis

380 6, 380 20, H04N 7167

Patent

active

052895416

ABSTRACT:
An off-premises method and apparatus for the interdiction of unauthorized channels of a broadband cable television signal includes common circuitry for adjusting the amplitude and equalization levels of the broadband CATV signals and one or more subscriber modules for generating jamming signals of different frequencies which are used to interdict one or more unauthorized channels. Each subscriber module is associated with a subscriber and is programmable and addressable to adjust the jamming parameters of that subscriber independently of other subscribers. Each subscriber module circuit comprises a plurality of latches, each of which is associated with one of a plurality of digital to analog converters. Each of the digital to analog converters drives one or more frequency agile oscillators with its analog output to generate the jamming signals. The subscriber module is based on a sequential state machine which loads frequency control words corresponding to the jammed channels from a frequency control memory into each latch on a cyclic basis. The basic cycle of the jamming machine includes the blanking of the frequency agile oscillator, the loading of a frequency control word into an associated latch and digital to analog converter to hop the oscillator to the next frequency, and then the unblanking of the oscillator to generate the new frequency. The state machine is adapted to vary the hopping rate, the frequency at which the system moves from channel to channel, to provide flexibility in providing various jamming effectiveness. The hopping rate is programmable and addressable and can be adjusted over a considerable range without affecting the substantially constant blanking period between hops.

REFERENCES:
patent: 3760097 (1973-09-01), Burroughs et al.
patent: 3896262 (1975-07-01), Hudspeth et al.
patent: 3899633 (1975-08-01), Sorenson et al.
patent: 3989887 (1976-11-01), Murphy
patent: 4039954 (1977-08-01), den Toonder
patent: 4091413 (1978-05-01), Herman
patent: 4148064 (1979-04-01), Reed
patent: 4334322 (1982-06-01), Clark, III
patent: 4342119 (1982-07-01), Seidl
patent: 4343042 (1982-08-01), Schrock et al.
patent: 4367557 (1983-01-01), Stern et al.
patent: 4434436 (1984-02-01), Kleykamp et al.
patent: 4450481 (1984-05-01), Dickinson
patent: 4498193 (1985-02-01), Richardson
patent: 4521809 (1985-06-01), Bingham et al.
patent: 4651204 (1987-03-01), Uemura
patent: 4737990 (1988-04-01), Kaneko
patent: 4769838 (1988-09-01), Hasegawa
patent: 4792971 (1988-12-01), Uemura
patent: 4825468 (1989-04-01), Ellis
patent: 4837820 (1989-06-01), Bellavia, Jr.
patent: 4841569 (1989-06-01), Wachob
patent: 4903297 (1990-02-01), Rist et al.
patent: 4912760 (1990-03-01), West, Jr. et al.
patent: 4914695 (1990-04-01), Martin
patent: 4963966 (1990-10-01), Harney et al.
patent: 5014309 (1991-05-01), West, Jr.
patent: 5068893 (1991-11-01), West et al.
patent: 5109286 (1992-04-01), West, Jr. et al.
patent: 5140633 (1992-08-01), Gurusami et al.
patent: 5142574 (1992-08-01), West, Jr. et al.
"Addressable Tap IT-1-SM" by Control Com, Inc.
"Tier Guard System" by E-Com Corporation.

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