Newsgroups: rec.video.cable-tv
Date: 1993-02-02 09:59:50 PST

________________________________________________________________________

    The Somewhat-Complete List of CATV/Satellite/Scrambling Patents
________________________________________________________________________

The following patents have been issued to their respective companies
from roughly 1970 through August of 1992.  The patents listed here in
some way relate to the area of televison encryption and/or distribution. 
Note that there are MANY other patents issued in this area to other
companies, individuals, etc. but I've chosen to include only the "major"
players in the Satellite / CATV industry. 

Copies of patents may be obtained from the U.S. Patent Office at a
charge of US$3.00 for each patent.  Send requests to Commissioner of
Patents and Trademarks, United States Patents and Trademarks Office,
Washington, D.C.  20231.  Also note that almost every state has at least
one Official Patent and Trademark Depository (usually at a large
institution or a start library) which has copies of all patents on
microfilm.  See 'comp.patents' for more information. 

Many other libraries may also have the "Official Gazette", the weekly
publication from the U.S. Patent Office which provides one drawing and
one paragraph from each patent issued during the week.  Armed with this
list, the "Gazette", and a few hours in the library, you can get a
better idea of the nature of the patents before ordering the full text
from the Patent Office. 

If someone is willing to donate FTP space, I can make a version of this
list available which has abstracts for any related patents issued in the
last two or three years.  Something of that size is simply too big to
post to the group.

Hope this is interesting / helpful to someone.

Regards,
Ed
________________________________________________________________________

(Note that the titles of some patents may be truncated...)

GENERAL INSTRUMENT CORPORATION
5115467: Signal Encryption Apparatus For Generating Common And Distinct Keys
5111504: Information Processing Apparatus With Replaceable Security Element
5107360: Optical Transmission Of RF Subcarriers In Adjacent Signal Bands
5091936: System For Communicating TV Signals Or A Plurality Of Digital Audio 
5083293: Prevention Of Alteration Of Data Stored In Secure IC Chip Memory
5081680: Initial Reporting Of Remotely Generated Data
5054067: Block-cipher Cryptographic Device Based Upon A Pseudorandom Nonlinear
5053992: Prevention Of Inspection Of Secret Data Stored In Encapsulated IC
5046093: CATV Subscriber Apparatus With Intelligent Remote Control
5038402: Apparatus And Method For Providing Digital Audio In The FM Broadcast
5036537: Geographic Black-out Method For Direct Broadcast Satellite System
5027399: Signal Switching Apparatus
5020129: Addressable Control System For CATV Program Distribution
5014310: Video Scrambling And Descrambling By Varying Sequence Of Segments In
5003591: Functionally Modifiable Cable Television Converter System
4989245: Controlled Authorization Of Descrambling Of Scrambled Programs
4982430: Bootstrap Channel Security Arrangement For Communication Network
4979230: Up-conversion Homodyne Receiver For Cable Television Converter With
4975951: IPPV Programming Distribution Control System
4956862: Method Of Providing Sound Privacy System Compatible With Mono And BTSC
4933898: Secure Integrated Circuit Chip With Conductive Shield
4928309: Method And Apparatus For Descrambling A Television Signal
4926477: Cable Television Descrambler
4920566: Dual Loop Sinewave Descrambler And Method Of Descrambling
4914695: Method And Apparatus For Frequency Control Of Multiple Oscillators
4864615: Reproduction Of Secure Keys By Using Distributed Key Generation Data
4864613: Broadband Converter/descrambler Interface For Cable TV
4860379: Data Communications System
4860353: Dynamic Feedback Arrangement Scrambling Technique Keystream Generator
4841569: Secure Video Distribution System
4821097: Apparatus And Method For Providing Digital Audio On The Sound Carrier
4815129: Video Encryption System
4803725: Cryptographic System Using Interchangeable Key Blocks And Selectable
4783846: Switchable Signal Source Module For Use With Cable Television Converter
4771456: Cable Television Channel Selector/descrambler For Use With Cable-ready
4739510: Direct Broadcast Satellite Signal Transmission System
4712239: Security Arrangement For Downloadable Cable Television Converters
4710955: Cable Television System With Two-way Telephone Communication Path
4694491: Cryptographic System Using Interchangeable Key Blocks And Selectable
4689619: Method And Apparatus For Polling Subscriber Terminals
4685131: Program Blocking Method For Use In Direct Broadcast Satellite System
4672440: Scrambled Signal Detector
4646150: Apparatus And Method For Stereo Television Sound
4638356: Apparatus And Method For Restricting Access To A Communication Network
4628358: Television Signal Encryption System With Protected Audio
4603349: Cable Television System With Stereo Sound Reproduction
4599647: Receiver With Interface For Interaction With Controller-decoder
4598318: Video Encryption System
4571615: Timing Generator For Sync Suppressed Television Signals
4562465: Adaptive Video Descrambling System
4558464: Address-programmable CATV Converter
4533948: CATV Communication System
4520508: Subscriber Terminal For Monitoring Radio-frequency Signal Ingress Into
4494111: Frequency Agile Security Apparatus
4477800: Security System
4477799: Security Apparatus With Alarm Search And Verification Capability
4404514: Fault Detection System As For Locating Faulty Connections In A Cable

OAK INDUSTRIES
4709266: Satellite Scrambling Communication Network Using Geographically
4688247: Pay TV Scrambling By Audio Encryption
4633309: Cable Television Master/slave Decoder Control
4568974: Video Scrambling By The Application Of A Variable Periodic Scrambling
4531021: Two Level Encripting Of RF Signals
4531020: Multi-layer Encryption System For The Broadcast Of Encrypted
4454543: Dynamic Video Scrambling
4447828: Phase Change Dynamic Scrambling
4425579: CATV Converter With Keylock To Favorite Channels
4424532: Coding And Decoding System For Video And Audio Signals
4353088: Coding And Decoding System For Video And Audio Signals
4340906: Video Signal Coding By Video Signal Polarity Reversal On The Basis Of
4336553: Method Of Coding Audio And Video Signals
4323922: Television Coding System With Channel Level Identification
4313132: Cable TV Security Means
4145717: Subscription TV Audio Carrier Recovery System
4135157: Pole Mounted Converter
4112464: Subscription TV Decoder Logic System
4024575: CATV Sine Wave Coding System
3919463: Pay TV System Using UHF Input
3882266: Apparatus For Converting Selected Channels
3857997: Cable Converter With Phase Lock Loop Techniques
3826863: Subscription Television System Using Audio And Video Carrier Reversal
3789131: Selective Coding System For Subscription Television

PIONEER ELECTRONICS CORPORATION
5125028: Television Signal Scrambling Method And Apparatus
5113441: Method For Scrambling A Television Signal And Method And Apparatus For
5113439: CATV Terminal And Video Apparatus Having A Noise Eliminating Circuit
5103477: Method And Apparatus For Descrambling A Television Signal
5091937: CATV Terminal Unit
5065235: CATV Terminal Unit Including Memory For Storing Remote Control Codes
5053884: Control Apparatus For Selectively Inhibiting Looking/listening In CATV
5031213: CATV Terminal Unit
5031045: CATV Terminal Device Having A Program Booking Timer Function
5029340: CATV Terminal Unit Having An Improved Descrambling Operation
5008934: CATV Transmission System Using Scrambled Signals
4962529: Scrambling Method For TV Picture
4961109: Chargeable Program Receiving Limit Setting System In Two-way Cable
4953208: CATV System Transmitting A Scrambled Television Signal
4949170: Video Information Transmission Service System And Head End Device
4928168: Billing Data Display System And Terminal Used Therein For A Closed
4926256: Billing Data Display System For A Closed Circuit Television System
4839922: CATV Scrambling And Descrambling Method
4794643: Method For Developing A Key Signal For Descrambling In Television
4792971: Selective Viewing Control System For CATV
4779129: FM Simultaneous Broadcast System For CATV
4769838: Community Antenna Television Reception Controlling Apparatus
4740835: Wire-tap Preventing Apparatus For Community Antenna Television
4737990: Unauthorized Channel Jamming Signal Applying Method For CATV System
4716410: CATV Data Transmission Method
4713840: Data Communication System
4710971: Channel Selecting Device For CATV Terminal Unit
4651204: Jamming Signal Generating Circuit
4648122: Community Antenna Television Communication System
4644396: Gate Circuit For Central Control Of CATV System
4641363: Community Antenna Television Communication System
4616214: Security System
4584684: Data Transmission Method
4558358: Cable Network Monitoring System For CATV System
4550341: Unauthorized Observation Preventing Device For CATV System
4455570: CATV System
4454538: Data Communication In CATV System
4439784: Power Cutting Device For Terminal Units Of CATV System
4427995: Fail-safe CATV System Center Facility
4408345: Remote Line Monitoring Method And Device For CATV System
4385314: Polling Pattern Generator For CATV System
4365267: Passive Data Monitor For Use With Polling Pattern Generator In CATV
4365249: Line Monitoring Device In Two-way Data Communication System
4322745: Television Signal Scrambling Method For CATV System
4317215: Tuning System For CATV Terminal
4313133: Scrambling And Descrambling System In CATV Broadcasting System
4270212: CATV Converter
4245245: Interactive CATV System
4149158: Security System For CATV Terminal
4145716: Descrambling Device In CATV System
4109281: Terminal Device For CATV
4064536: Video Scrambler And Descrambler Apparatus

SCIENTIFIC-ATLANTA
5109286: CATV Reverse Path Manifold System
5077607: Cable Television Transaction Terminal
5068893: Television Signal Processing Network For Subscription Television
5058160: In-band Controller
5053883: Terminal Polling Method
5029207: External Security Module For A Television Signal Decoder
5014309: Off-premises Cable Television Channel Interdiction Method And Apparatus
5003384: Set-top Interface Transactions In An Impulse Pay Per View Television
5001554: Terminal Authorization Method
4994908: Interactive Room Status/time Information System
4991011: Interactive Television Terminal With Programmable Background Audio Or
4987486: Automatic Interactive Television Terminal Configuration
4963966: CATV Distribution System, Especially Adapted For Off-premises Premium
4924498: Method And Apparatus For Improving Video Scrambling And Employing
4922532: Sync Suppression Scrambling And Descrambling Of Television Signals For
4912760: Off-premises Cable Television Channel Interdiction Method And Apparatus
4912721: Cable Television Spread Spectrum Data Transmission Apparatus
4890321: Communications Format For A Subscription Television System Permitting
4890319: Method For Controlling Copying Of Protected Information Transmitted
4888799: Scrambling Of Signals By Inversion
4885775: Information Display Scheme For Subscribers Of A Subscription
4866770: Method And Apparatus For Communication Of Video, Audio, Teletext, And
4829569: Communication Of Individual Messages To Subscribers In A Subscription
4817142: Restoring Framing In A Communications System
4792972: Remote Programming Of CATV Channel Authorization Unit
4792848: Cable Television Impulse Pay Per View System
4748667: Jamming Signal Scrambling And Descrambling Systems For CATV
4691353: Scrambling Systems For CATV
4642688: Method And Apparatus For Creating Encrypted And Decrypted Television
4636852: Scrambling And Descrambling Of Television Signals For Subscription TV
4567517: Descrambler For Sync-suppressed TV Signals
4523228: Sync Suppression Scrambling Of Television Signals For Subscription TV
4471380: Scrambling And Descrambling Of Television Signals For Subscription TV
4466017: Sync Suppression Scrambling Of Television Signals For Subscription TV

TOCOM, INC.
4606072: Master/slave Converter System
4575755: Video Encoder/decoder System
4574305: Remote Hub Television And Security Systems
4536791: Addressable Cable Television Control System With Video Format Data
3993955: Method Of And Apparatus For Establishing Emergency Communications In A
3990012: Remote Transceiver For A Multiple Site Location In A Two-way Cable
3846703: Noise Control System For Transmission Network
3803491: Communications System
3794922: Data Sampling Communication System

ZENITH ELECTRONICS, INC.
5052047: Modulator-remodulator With Common Local Oscilator
5018197: Secure Video Decoder System
4995080: Television Signal Scrambling System And Method
4947429: Pay Per View Television Signaling Method
4944006: Secure Data Packet Transmission System And Method
4910767: Ani Auto Dialer With Carrier Current Interface
4885794: Method And Apparatus For Protection Of Channel Access In Broadband
4885776: Television Signal Encoder With Reduced Transient Switching Effects
4876718: Secure Data Packet Transmission System And Method
4837820: Hybrid CATV Scrambling System
4817144: Secure TV Scrambling System Using Framing Code Switching
4807023: Mapping Method For Impulse Pay Per View System
4802213: Sound Masking In Phase Reversal TV Scrambling System
4802212: Method And Device For Preventing Tape Piracy
4790011: Auto Clamp For Modulator For Suppressed Sync Signals
4790010: Enhanced Scrambling Method And System For TV Signals
4771458: Secure Data Packet Transmission System And Method
4768229: Restrictive Access Control System
4766497: If Circuit With Reduced Sound Attenuation For Cable Signals
4759061: Technique For Toggling Coding Mode In A Television Signal Encoder
4755872: Impulse Pay Per View System And Method
4748501: Cable Converter For Television Signals With Stereo Audio Signal
4742513: Adaptive Window Multiplexing Technique
4717970: Video System With Programmable Vcr
4712237: Method And Apparatus For Unscrambling Sync-suppressed Television
4706284: Television Signal Data Transmission System
4706283: Television Signal Scrambling System
4703354: Non-linear Sync Signal Processing Circuit
4691354: Vertical Interval Data Blanker
4688246: CATV Scrambling System With Compressed Digital Audio In Synchronizing
4677685: Method And Apparatus For Downloading A Code Defining The Channel
4667232: Synchronizing Pulse Restoration Circuit
4654705: Two Channel Audio Scrambling System
4636853: Dynamic Audio Scrambling System
4633316: Stable Low Cost 4.5 Mhz Remodulator
4630113: Baseband CATV Decoder With Stereo Bypass
4612571: Constant Z Bandswitched Input Filter
4611242: Two Mode Scrambling System Using Identifier Pulse In Vertical Blanking
4602284: Adapter For Rendering A Non-addressable CATV Converter Addressable
4600921: Full-field Teletext System With Dynamic Addressability
4598313: Television Signal Scrambling System
4586078: CATV Upstream Signal Transmission At Nonharmonic Video Frequencies
4581637: Pin Diode Modulator
4574163: Digital Radio Telephone
4571560: Switched Bandpass Filter
4558360: Decoder Lockout Defeat Circuit
4554581: STV Decoder With Improved Data Signal Recognition Capability
4554579: Two-way CATV System With AML Commands
4553161: Upstream Data Packet Time Slot Synchronization With Downstream Vbi For
4528663: Peak Load Access In A Two-way CATV Contention System
4527194: Channel Assignment For CATV System
4520507: Low Noise CATV Converter
4514761: Data Encryption Technique For Subscription Television System
4503462: Automatic Homing System For A Subscription Television Signal Decoder
4489347: Sine-wave Decoding Technique
4476488: Control Circuit For CATV Alert System
4467353: Television Signal Scrambling System And Method
4461032: CATV Service Controller
4460922: Memory Select System For An STV Decoder
4458268: Sync Displacement Scrambling
4408225: Subscription Television Decoder
4395734: Remote Muting For CATV/STV Converters
4388645: Teletext Communication System With Timed Multipage Local Memory
4375651: Selective Video Reception Control System
4370675: Doorbell Actuated Television Security System
4292650: STV Subscriber Address System
3780213: Air Code Burst Generator
3737785: Solid-state Signal Distribution System
3732355: Inhibitable Random Pulse Generator
3538242: Subscriber Communition System
3531583: Subscription Television Receiver
3531582: Subscription Television Receiver With Removable Code-bearing Element
3480726: Adjustable Switching Apparatus
3475547: Subscription Television Receiver With Program Use Recording
3466385: Correlation Testing Arrangement For A Subscription Television Receiver
3453380: Variable Delay Network