Patents by Inventor Kevin T. Chang

Kevin T. Chang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20140029747
    Abstract: A system is provided for use with secure content in a first format. The system includes a conditional access device, a transcoding device and a media processor. The conditional access device is operable to receive the secure content and can generate a second secure content based on the secure content. The conditional access device can further provide the second secure content to the transcoding device.
    Type: Application
    Filed: July 25, 2012
    Publication date: January 30, 2014
    Applicant: GENERAL INSTRUMENT CORPORATION
    Inventors: John P. Kamieniecki, Tat Keung Chan, Kevin T. Chang, Alexander Medvinsky
  • Patent number: 8375415
    Abstract: The present invention is an upstream power control system, within a cable modem which controls the power consumption of the cable modem. The power control system comprises a MAC chip which synchronizes upstream communication signals for transmission to a cable network and outputs an upstream control signal, an upstream amplifier which receives the synchronized upstream communication signals, and a complex programmable logic device (CPLD). The CPLD controls the upstream amplifier in response to the upstream control signal such that the upstream amplifier is powered on during transmission of the communication signals, and powered off when not transmitting, which results in the reduction of power consumed by the cable modem.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: February 12, 2013
    Assignee: General Instrument Corporation
    Inventors: Matthew Waight, Yucheng Jin, Kevin T. Chang
  • Publication number: 20120159146
    Abstract: A system is provided for use with secure content in a first format. The system includes a conditional access device, a transcoding device and a media processor. The conditional access device is arranged to receive the secure content and can generate second secure content based on the secure content. The conditional access device is can further provide the second secure content to the transcoding device. The transcoding device can transcode the second secure content into transcoded content of a second format, can secure the transcoded content as secure transcoded content and can provide the secure transcoded content to the media processor.
    Type: Application
    Filed: December 20, 2010
    Publication date: June 21, 2012
    Applicant: GENERAL INSTRUMENT CORPORATION
    Inventors: John P. Kamieniecki, Kevin T. Chang
  • Patent number: 7742777
    Abstract: A dynamic arrangement for reducing the presence of ingress noise in the upstream signal path of a two-way cable system utilizes a variable attenuation element and amplifier disposed along the upstream signal path. The amplifier includes a bypass switch so that the amplifier may be switched in to or out of the upstream path. A signal processor associated with the communications gateway functions to calculate the upstream loss present at the gateway and control the operation of the attenuation element, amplifier and bypass switch accordingly. Upstream attenuation is selected to be as large as possible, yet still allow in-building cable devices to communicate with their associated head end (HE) receiver equipment, after accounting for maximum transmit limitations.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: June 22, 2010
    Assignee: General Instrument Corporation
    Inventors: Jay Strater, Dean Stoneback, Kevin T. Chang
  • Patent number: 7680251
    Abstract: A method and apparatus for preventing false alarm activation is provided. According to one embodiment of the invention, a determination (410) is made as to whether an instruction from a controller is a commanded reset, and control of a Subscriber Line Interface Circuit is taken (416) from a voice processor circuit when the instruction is a commanded reset.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: March 16, 2010
    Assignee: Motorola, Inc.
    Inventors: Marlin F. McGregor, Kevin T. Chang, Ben M. Foose
  • Patent number: 7610034
    Abstract: A double conversion tuner system is disclosed that avoids the problem of degraded performance as a result of radiated interferers. Several selection criteria are described for specifying the parameters of the tuner, including the nominal first or high intermediate frequency, a first local oscillator signal for each desired channel, a nominal second local oscillator signal, and a bandwidth of the first intermediate frequency.
    Type: Grant
    Filed: October 18, 2005
    Date of Patent: October 27, 2009
    Assignee: General Instrument Corporation
    Inventor: Kevin T. Chang
  • Patent number: 7039432
    Abstract: A dynamic arrangement for reducing the presence of ingress noise in the upstream signal path of a two-way cable system utilizes a variable attenuation element and amplifier disposed along the upstream signal path. The amplifier includes a bypass switch so that the amplifier may be switched in to or out of the upstream path. A signal processor associated with the communications gateway functions to calculate the upstream loss present at the gateway and control the operation of the attenuation element, amplifier and bypass switch accordingly. Upstream attenuation is selected to be as large as possible, yet still allow in-building cable devices to communicate with their associated head end (HE) receiver equipment, after accounting for maximum transmit limitations.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: May 2, 2006
    Assignee: General Instrument Corporation
    Inventors: Jay Strater, Dean Stoneback, Kevin T. Chang
  • Patent number: 6816512
    Abstract: An arrangement for controlling multiple telephone lines terminating in a single residence uses a multiplexer within a communications gateway and a plurality of demultiplexers, each demultiplexer coupled to a separate one of telephone lines. The communications gateway functions to convert all received analog telephony signals into a digital format and then multiplexes the digital signals onto a single telephone line connected to the residence. The various telephone lines in the residence are connected in series along the line, using a number of drop-off points. The demultiplexer on each telephone line is configured to recognize the time slots within the multiplexed signal destined for its associated telecommunications device. In a similar fashion, separate time slots are assigned for upstream transmission from each telecommunication device into the HFC network.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: November 9, 2004
    Assignee: General Instrument Corporation
    Inventors: David B. Lazarus, Yucheng Jin, James D. Rosemary, Matthew G. Waight, Kevin T. Chang
  • Publication number: 20030114112
    Abstract: A dynamic arrangement for reducing the presence of ingress noise in the upstream signal path of a two-way cable system utilizes a variable attenuation element and amplifier disposed along the upstream signal path. The amplifier includes a bypass switch so that the amplifier may be switched in to or out of the upstream path. A signal processor associated with the communications gateway functions to calculate the upstream loss present at the gateway and control the operation of the attenuation element, amplifier and bypass switch accordingly. Upstream attenuation is selected to be as large as possible, yet still allow in-building cable devices to communicate with their associated head end (HE) receiver equipment, after accounting for maximum transmit limitations.
    Type: Application
    Filed: December 4, 2002
    Publication date: June 19, 2003
    Inventors: Jay Strater, Dean Stoneback, Kevin T. Chang
  • Publication number: 20030033608
    Abstract: A cable system having a splitter for coupling a drop interface to a cable modem and pass-through to a home interface. The pass-through is provided with an RF module having separate forward and return paths to selectively provide unimpeded, partially impeded and fully impeded cable service in the forward and return paths. Amplifiers in the forward and return paths are controlled to avoid excessive insertion loss and to provide power equalization in the return path to limit ingress noise to the home.
    Type: Application
    Filed: August 10, 2001
    Publication date: February 13, 2003
    Applicant: General Instrument Corporation
    Inventors: Kevin T. Chang, Richard Moore, Jay Strater
  • Patent number: 6477253
    Abstract: A method and device for scrambling video signals for broadcast in a proprietary television system includes modifying the vertical or horizontal synchronization pulses of the video signal to prevent unauthorized viewers from properly displaying the programming content. Preferably, the vertical sync pulses are removed from the signal prior to broadcast and replaced with horizontal sync pulses. A descrambler used with the receiving television uses the manner in which the false horizontal sync pulses were inserted into the video signal to recreate a sufficient approximation of the vertical sync pulses.
    Type: Grant
    Filed: January 13, 1999
    Date of Patent: November 5, 2002
    Assignee: General Instrument Corporation
    Inventors: Timothy D. Rea, Alfred W. Stufflet, Kevin T. Chang
  • Publication number: 20020133829
    Abstract: The present invention is an upstream power control system, within a cable modem which controls the power consumption of the cable modem. The power control system comprises a MAC chip which synchronizes upstream communication signals for transmission to a cable network and outputs an upstream control signal, an upstream amplifier which receives the synchronized upstream communication signals, and a complex programmable logic device (CPLD). The CPLD controls the upstream amplifier in response to the upstream control signal such that the upstream amplifier is powered on during transmission of the communication signals, and powered off when not transmitting, which results in the reduction of power consumed by the cable modem.
    Type: Application
    Filed: March 19, 2001
    Publication date: September 19, 2002
    Inventors: Matthew Waight, Yucheng Jin, Kevin T. Chang
  • Publication number: 20010033585
    Abstract: An arrangement for controlling multiple telephone lines terminating in a single residence uses a multiplexer within a communications gateway and a plurality of demultiplexers, each demultiplexer coupled to a separate one of telephone lines. The communications gateway functions to convert all received analog telephony signals into a digital format and then multiplexes the digital signals onto a single telephone line connected to the residence. The various telephone lines in the residence are connected in series along the line, using a number of drop-off points. The demultiplexer on each telephone line is configured to recognize the time slots within the multiplexed signal destined for its associated telecommunications device. In a similar fashion, separate time slots are assigned for upstream transmission from each telecommunication device into the HFC network.
    Type: Application
    Filed: December 29, 2000
    Publication date: October 25, 2001
    Inventors: David B. Lazarus, Yucheng Jin, James D. Rosemary, Matthew G. Waight, Kevin T. Chang
  • Patent number: 6260193
    Abstract: A system for synchronizing one or more decoders with a network sync signal at a headend of a television communication network. The system allows decoders to transmit upstream messages synchronously in time slots which are defined according to the network sync signal, thereby improving system throughput. Identifying data is provided in a blanking interval (VBI or HBI) of one or more television signals to designate a horizontal scan line of the respective television signal which follows a reference point in the network sync signal by a predetermined delay. At each decoder, the identifying data is recovered, and the onset of the designated scan line can be used to signal the start of a transmission for the decoder. Preferably, the identifying data is provided in each television signal so the user is not forced to tune to a particular television channel to transmit a message. Various channel access protocols may be used, such as a session oriented protocol, or a synchronized ALOHA protocol.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: July 10, 2001
    Assignee: General Instrument Corporation
    Inventors: Kevin T. Chang, David E. Chodelka, Charles E. Schell, III, Sam Reichgott
  • Patent number: 6072872
    Abstract: A signal such as an analog scrambled television signal in a cable television network has first scrambling mode data which is compatible with a first decoder population, but not a second decoder population. The scrambled television signal is processed to determine the scrambling mode without recovering the first scrambling mode data. Second scrambling mode data which is compatible with the second decoder population is then provided in the scrambled television signal, for example, in the vertical blanking interval or on an audio subcarrier. During processing to determine the scrambling mode, the television signal is delayed, e.g., by digitizing it and temporarily storing it in memory. The delay compensates for the time required to determine the scrambling mode. The television signal is recovered in the analog domain prior to inserting the second scrambling mode data.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: June 6, 2000
    Assignee: General Instrument Corporation
    Inventors: Kevin T. Chang, Alfred W. Stufflet
  • Patent number: D562813
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: February 26, 2008
    Assignee: General Instrument Corporation
    Inventors: William J. Storti, Kevin T. Chang, Barry P. Falvo, Paul Ocepek
  • Patent number: D745480
    Type: Grant
    Filed: December 22, 2014
    Date of Patent: December 15, 2015
    Assignee: ARRIS Enterprises, Inc.
    Inventors: Carol Mathews, Yung-Chun Lun, Gary A. Dorfner, Chin-Tan Chang, Kevin T. Chang