Patents Assigned to Zenith Electronics Corporation
  • Publication number: 20090024897
    Abstract: Normally ordered robust VSB data are reordered in accordance with a first interleave to produce reordered robust VSB data. The reordered robust VSB data and ATSC data are reordered in accordance with a second interleave to produce normally ordered robust VSB data and reordered ATSC data. The normally ordered robust VSB data and reordered ATSC data are time multiplexed for transmission to a receiver. The receiver discards the reordered ATSC data or the normally ordered robust VSB data depending upon receiver type or user selection. A robust VSB receiver is able to process the normally ordered robust VSB data upstream of an outer decoder without an interleave thereby avoiding the delay associated with an interleave.
    Type: Application
    Filed: October 31, 2007
    Publication date: January 22, 2009
    Applicant: Zenith Electronics Corporation
    Inventors: Wayne E. Bretl, Richard W. Citta, Mark Fimoff
  • Patent number: 7349470
    Abstract: Constrained feedback tap weights of a decision feedback equalizer are determined by iteratively solving a non-linear equation for a constraint multiplier. The non-linear equation is based on a 2-norm of feedback tap weights constrained by an explicit constraint constant.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: March 25, 2008
    Assignee: Zenith Electronics Corporation
    Inventor: William J. Hillery
  • Patent number: 7327810
    Abstract: In forming a channel estimate, a received signal y is decoded to form data s, a convolution matrix ? is formed from the data s, a matrix F is formed from the data s such that the matrix F results from the forming of the matrix ? as a convolution matrix, and a conjugate gradient algorithm is performed to determine the channel estimate. The conjugate gradient algorithm is based on the received signal y, the matrix ?, and the matrix F.
    Type: Grant
    Filed: December 5, 2003
    Date of Patent: February 5, 2008
    Assignee: Zenith Electronics Corporation
    Inventors: Jin H. Kim, Serdar Ozen
  • Patent number: 7327790
    Abstract: An MPEG on-screen display coder includes a buffer, an MPEG encoder, and a multiplexer. The buffer receives and buffers an MPEG transport data stream containing frames of a selected program and frames of a non-selected program. The MPEG encoder encodes frames of the selected program with an on-screen display. The multiplexer selectively passes to a digital television receiver the frames of the non-selected program, the encoded frames of the selected program, and original frames of the selected program.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: February 5, 2008
    Assignee: Zenith Electronics Corporation
    Inventors: Wayne E. Bretl, Mark Fimoff, Paul A. Snopko
  • Patent number: 7324591
    Abstract: A channel impulse response is determined from a cross-correlation of a received training sequence and a stored version of the transmitted training sequence. The channel impulse response is iteratively cleansed of noise caused by the finiteness of the cross-correlation. Initial values of the tap weights for the taps of an equalizer such as a decision feedback equalizer may be determined based on the cleansed channel impulse response.
    Type: Grant
    Filed: August 17, 2004
    Date of Patent: January 29, 2008
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, Sreenivasa M. Nerayanuru, Sedar Ozen
  • Patent number: 7313182
    Abstract: Constrained tap weights of a decision feedback equalizer are determined according to the channel impulse response of a channel and a constraint function. The constraint function is differentiable and is an approximation of a non-differentiable tap weight constraint function. The tap weight constraint function may have a constraint value M that is a function of a mean squared error of the estimated mean squared error at the output of the decision feedback equalizer.
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: December 25, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, William J. Hillery, Michael D. Zoltowski
  • Patent number: 7313208
    Abstract: A low cost DTV translator, which translates an incoming signal on channel A to an outgoing signal on channel B, includes a transmitter pre-equalizer whose taps are configured with tap values that pre-distort a signal so as to negate distortion caused by a high power amplifier and emission mask filter at the output of the DTV translator. This pre-distortion is accomplished by using the transmitter of the DTV translator to provided a reference signal and to use the receiver of the DTV translator as a reference receiver for the reference signal to thereby avoid the use of a more expensive external reference receiver.
    Type: Grant
    Filed: November 3, 2003
    Date of Patent: December 25, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Timothy V. Frahm, Gary J. Sgrignoli
  • Patent number: 7310505
    Abstract: A tuner includes an RF input with a signal level controller such as an attenuator that is provided to attenuate a signal from the RF input. A tunable RF filter provides RF band limiting and determines simultaneously the AGC bandwidth. An amplifier with resistive feedback provides first and second outputs which, together, represent the incident power of the attenuated signal delivered by the amplifier, thus eliminating the need for a directional coupler and rendering this part of the tuner compatible with integration. A feedback circuit responds to the incident power of the attenuated signal by controlling the attenuation (AGC) provided by the signal level controller.
    Type: Grant
    Filed: September 9, 2003
    Date of Patent: December 18, 2007
    Assignee: Zenith Electronics Corporation
    Inventor: Pierre Dobrovolny
  • Patent number: 7310354
    Abstract: A synchronous data link signal is generated for supply between digital television equipment in a studio and an RF transmitter. The synchronous data link signal includes first data to be encoded at a first data rate, second data to be encoded at a second data rate less than the first data rate, and a map defining the relative amounts and placement of the encoded first and second data in the synchronous data link signal. The first data is in the form of first output data packets of a predetermined size. The second data and the map data are multiplexed so as to provide more than one second output data packet having the predetermined size. The first and second output data packets are then multiplexed so as to provide the synchronous data link signal.
    Type: Grant
    Filed: July 18, 2002
    Date of Patent: December 18, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, Raymond C. Hauge, Timothy G. Laud
  • Patent number: 7305026
    Abstract: An equalizer for processing blocks of data includes n?1 data shifters, n finite filters, an adder, and a controller. Each of the n?1 data shifters shifts the blocks of data. One of the n finite filters applies a corresponding set of finite filter coefficients to the blocks of data, and each of the other n?1 finite filters applies a set of finite filter coefficients to a corresponding output of the n?1 data shifters. Ghosts of the blocks of data are not eliminated as a result of the application of the n sets of finite filter coefficients corresponding to the n finite filters, and n>2. The adder is arranged to add outputs from the n finite filters. The controller is arranged to control the sets of finite filter coefficients corresponding to the n finite filters so that the addition performed by the adder substantially eliminates the ghosts.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: December 4, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Richard W. Citta, Scott M. LoPresto, Jingsong Xia
  • Patent number: 7289580
    Abstract: An impulse response of a channel is estimated by correlating a received signal with a stored vector. The received signal contains a training sequence having a length Ltr, the stored vector has a length Lsv, Ltr/n=Lsv, and n is greater than two. The signal is received by a device. The vector is determined based on the training sequence and an ideal channel. The ideal channel is an idealized form of a channel through which the device receives the signal. A plurality of correlations may be performed where each correlation provides a substantially noise-free estimate of the impulse response of a different portion of the channel. The correlations are combined to provide an estimate of the impulse response of the channel.
    Type: Grant
    Filed: October 9, 2002
    Date of Patent: October 30, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Christopher J. Pladdy, Mark Fimoff, Sreenivasa M. Nerayanuru, Serdar Ozen, Michael D. Zoltowski
  • Patent number: 7277505
    Abstract: A receiver receives a digital signal. The digital signal contains a frame of robust VSB data and ATSC data, and the digital signal further contains a map. The map contains information indicating a location of the robust VSB data and ATSC data in the frame. A decoder of the receiver decodes the digital signal. A processor of the receiver processes at least one of the robust VSB data and the ATSC data according to the location information contained in the map.
    Type: Grant
    Filed: May 6, 2004
    Date of Patent: October 2, 2007
    Assignee: Zenith Electronics Corporation
    Inventor: Mark Fimoff
  • Patent number: 7239679
    Abstract: An impulse response is estimated for a channel by estimating an intermediate impulse response of the channel. The intermediate impulse response comprises at least one multipath spike and one or more non-deterministic noise components at locations throughout the channel. Then, a threshold function is applied to the estimated intermediate impulse response across at least a portion of the channel in order to provide an estimated final impulse response of the channel. The threshold function has the effect of nulling the noise components of the channel having values less than the threshold function at the location within the channel of the respective noise component, and the threshold function is characterized by a level that varies across the portion of the channel from a minimum value to a maximum value in a manner determined by the location of the at least one multipath spike within the channel.
    Type: Grant
    Filed: August 26, 2002
    Date of Patent: July 3, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, Sreenivasa M. Nerayanuru, Christopher J. Pladdy
  • Patent number: 7215714
    Abstract: Normally ordered robust VSB data are reordered in accordance with a first interleave to produce reordered robust VSB data. The reordered robust VSB data and ATSC data are reordered in accordance with a second interleave to produce normally ordered robust VSB data and reordered ATSC data. The normally ordered robust VSB data and reordered ATSC data are time multiplexed for transmission to a receiver. The receiver discards the reordered ATSC data or the normally ordered robust VSB data depending upon receiver type or user selection. A robust VSB receiver is able to process the normally ordered robust VSB data upstream of an outer decoder without an interleave thereby avoiding the delay associated with an interleave.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: May 8, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Wayne E. Bretl, Richard W. Citta, Mark Fimoff
  • Patent number: 7203257
    Abstract: A channel impulse response for a channel is determined by determining an initial channel impulse response estimate based upon a stored training sequence and a received signal, by thresholding the initial channel impulse response estimate, by estimating a noise variance for the channel based upon the stored training sequence, the thresholded initial channel impulse response estimate, and the received signal, by determining an inverse of a covariance matrix based on the estimated noise variance and the thresholded initial channel impulse response estimate, by updating the channel impulse response based on the inverse covariance matrix, the stored training sequence, and the received signal, and by thresholding the updated channel impulse response estimate.
    Type: Grant
    Filed: May 23, 2003
    Date of Patent: April 10, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, Sreenivasa M. Nerayanuru, Serdar Ozen, Christopher J. Pladdy, Michael D. Zoltowski
  • Patent number: 7190720
    Abstract: Initial values of the tap weights for the taps of a linear equalizer are determined based on a channel impulse response of a channel so that the values corresponding to the weights of the equalizer taps achieve optimum initialization of the equalizer. These values are determined through use of a nested summation where the number of summations is dependent upon the number of multi-paths characterizing the channel.
    Type: Grant
    Filed: May 9, 2002
    Date of Patent: March 13, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, Serdar Ozen, Michael D. Zoltowski
  • Patent number: 7187698
    Abstract: Normally ordered robust VSB data are reordered in accordance with a first interleave to produce reordered robust VSB data. The reordered robust VSB data and ATSC data are reordered in accordance with a second interleave to produce normally ordered robust VSB data and reordered ATSC data. The normally ordered robust VSB data and reordered ATSC data are time multiplexed for transmission to a receiver. The receiver discards the reordered ATSC data or the normally ordered robust VSB data depending upon receiver type or user selection. A robust VSB receiver is able to process the normally ordered robust VSB data upstream of an outer decoder without an interleave thereby avoiding the delay associated with an interleave.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: March 6, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Wayne E. Bretl, Richard W. Citta, Mark Fimoff
  • Patent number: 7177354
    Abstract: The tap weights of an equalizer are initialized in response to a received relatively short training sequence, and new tap weights for the equalizer are thereafter successively calculated in response to relatively long sequences of received symbols and corresponding sequences of decoded symbols. These new tap weights are successively applied to the equalizer.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: February 13, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, William Hillery, Sreenivasa M. Nerayanuru, Serdar Ozen, Christopher J. Pladdy, Michael D. Zoltowski
  • Patent number: 7177343
    Abstract: A compound chirp is provided in a received signal to permit a receiver to synchronize to the received signal. The compound chirp has temporally overlapping up frequency and down frequency components.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: February 13, 2007
    Assignee: Zenith Electronics Corporation
    Inventors: Richard W. Citta, Jingsong Xia
  • Patent number: 7110447
    Abstract: An impulse response of a channel is estimated by cross-correlating a known training signal with a received training signal to produce a cross-correlation vector. The cross-correlation vector is characterized by a known noise component resulting from the finiteness of the correlation. A correction vector is estimated based on the known training signal, where the correction vector is related to the noise component. Truncated representations of the correction vector are iteratively subtracted from the cross-correlation vector in order to produce a succession of cross-correlation outputs of increased accuracy. When the cross-correlation output is sufficiently accurate, it may be used to determine the weights to be given to the taps of an equalizer.
    Type: Grant
    Filed: May 9, 2002
    Date of Patent: September 19, 2006
    Assignee: Zenith Electronics Corporation
    Inventors: Mark Fimoff, Sreenivasa M. Nerayanuru, Sedar Ozen