| Patent Number |
Title Of Patent |
Date Issued |
| RE38456 |
Decimation of baseband DTV signals prior to channel equalization in digital television signal re |
March 9, 2004 |
| A radio receiver uses the same tuner for receiving a selected digital television (DTV) signal, irrespective of whether it is a quadrature-amplitude-modulation (QAM) or a vestigial sideband (VSB) signal. The final IF signal is digitized at a rate that is a multiple of both the symbol |
| 7151797 |
Adaptive K-factor-improvement filter for receiver of radio signals subject to multipath distorti |
December 19, 2006 |
| An adjustable K-factor-improvement (KFI) filter having a sparse kernel composed of non-zero weighting coefficients of substantially equal amplitudes is included in a receiver for digital television signals or the like. The receiver includes apparatus for measuring the channel impulse |
| 7050491 |
Adaptive equalization of digital modulating signal recovered from amplitude-modulated signal sub |
May 23, 2006 |
| An adaptive equalizer for amplitude-modulation (AM) signal received by over-the-air radio transmission comprises feed-forward finite-impulse-response (FIR) filtering and further comprises infinite-impulse-response (IIR) filtering for feeding back decisions. The echo content of baseba |
| 6950481 |
Digital television receiver converting vestigial-sideband signals to double-sideband AM signals |
September 27, 2005 |
| A vestigial-sideband (VSB) signal is converted to a double-sideband amplitude-modulation signal having information that is subsequently detected in the double-sideband amplitude-modulation signal. A method for performing the conversion includes mixing the VSB signal with a first beat |
| 6816204 |
Ghost cancellation reference signals for broadcast digital television signal receivers and recei |
November 9, 2004 |
| Broadcast DTV signals are improved by including in each of their successive data fields a training signal for the adaptive channel-equalization and echo-cancellation filtering in receivers. The training signal in each data field includes a prescribed number of cycles of a particular pseu |
| 6803970 |
Digital television receiver with match filter responsive to field synchronization code |
October 12, 2004 |
| A radio receiver for receiving a selected digital TV signal uses final intermediate frequency signals the carrier frequencies of which are multiples of symbol rate. The radio receiver has a match filter receptive of rectified samples of digitized intermediate-frequency signal and res |
| 6771707 |
Digital television receiver converting vestigial-sideband signals to double-sideband AM signals |
August 3, 2004 |
| A vestigial-sideband (VSB) signal is down-converted to generate a VSB signal including a carrier frequency offset from zero frequency by an amount greater than the bandwidth of the VSB signal. The carrier of this final I-F signal has a carrier offset from zero-frequency, which carrier |
| 6768517 |
Repetitive-PN1023-sequence echo-cancellation reference signal for single-carrier digital televis |
July 27, 2004 |
| DTV signals transmitted over the air with a symbol rate of around 10.76 million samples per second include echo-cancellation reference (ECR) signals each of which includes or essentially consists of a repetitive-PN1023 sequence with baud-rate symbols, which repetitive-PN1023 sequence |
| 6760078 |
Digital filtering of DTV I-F signal to avoid low-end boost of the baseband signal resulting from |
July 6, 2004 |
| In a radio receiver for digital television signals a digital filter supplies the in-phase synchrodyning circuitry a shaped spectral response to the digitized I-F signal. The amplitude-versus-frequency response of the digital filter rolls off through the carrier region, so that there is |
| 6687313 |
Digital television receiver converting vestigial-sideband signals to double-sideband AM signals |
February 3, 2004 |
| A vestigial-sideband (VSB) signal is converted to a double-sideband amplitude-modulation final intermediate-frequency signal that is subsequently detected to generate a baseband demodulation result. The carrier of this final I-F signal has a carrier offset from zero-frequency, which |
| 6667760 |
Receiver for digital television signals having carriers near upper frequency boundaries of TV br |
December 23, 2003 |
| In a receiver for receiving digital television (DTV) signals with carriers near the upper frequency boundaries of TV broadcasting channels, co-channel interfering NTSC video carrier and its lower frequency sidebands are removed from intermediate-frequency signal by trap filtering, pr |
| 6643334 |
Bandpass tracker for DTV receiver, with VSB I-F signal filtered for more symmetrical AFPC Loop r |
November 4, 2003 |
| Digital radio receivers for digital television signals often employ bandpass trackers in which the bandwidth of the automatic-frequency-and-phase-control (AFPC) loop is determined in the baseband by lowpass filtering after demodulating the intermediate frequency signal. If the I-F si |
| 6621527 |
Digital receiver with match filter responsive to field synchronization code in the final I-F sig |
September 16, 2003 |
| A radio receiver for receiving a selected digital TV signal uses final intermediate frequency signals the carrier frequencies of which are multiples of symbol rate. The radio receiver has a match filter receptive of rectified samples of digitized intermediate-frequency signal and res |
| 6608869 |
Dual-carrier heterodyne for separating orthogonal components of complex amplitude-modulation sig |
August 19, 2003 |
| A method for receiving a modulated carrier wave with asymmetrical upper and lower sidebands, which carrier wave may be suppressed, is described. A first down-converter in the receiver heterodynes the asymmetrical upper and lower sidebands of the modulated carrier wave being received with |
| 6606129 |
Digital filtering of DTV I-F signal to avoid low-end boost of the baseband signal resulting from |
August 12, 2003 |
| In a radio receiver for digital television signals a digital filter supplies the in-phase synchrodyning circuitry a shaped spectral response to the digitized I-F signal. The amplitude-versus-frequency response of the digital filter rolls off through the carrier region, so that there is |
| 6573948 |
Equalizing intermediate-frequency signals before demodulating them in a digital television recei |
June 3, 2003 |
| Adaptive passband equalization filtering comprises in addition to a non-iterative portion, an iterative filtering portion to suppress longer-delayed post-ghosts. This iterative filtering portion differs from that in previous adaptive passband equalization filtering, in which the esti |
| 6545728 |
Digital television receivers that digitize final I-F signals resulting from triple-conversion |
April 8, 2003 |
| Receiving apparatus for digital television signals digitizes a final intermediate frequency signal supplied from a triple-conversion radio receiver and synchrodynes the digitized final intermediate frequency signal to baseband. The triple-conversion radio receiver selects one of a pl |
| 6535553 |
Passband equalizers with filter coefficients calculated from modulated carrier signals |
March 18, 2003 |
| A digital communications radio receiver, as for television, digitizes a final intermediate-frequency signal offset from zero frequency no more than a few megahertz. This digitized final I-F signal is passed through an adaptive equalizer before being synchrodyned to baseband in the digita |
| 6519416 |
Magnet recording/reproducing apparatus with video camera, suited for photorecording without atte |
February 11, 2003 |
| Recording/reproducing apparatus including recording electronics and playback electronics and a radio receiver responsive to a selected television signal for supplying a composite video signal to the recording electronics at selected times are contained within a unitary package design |
| 6519304 |
Circuitry operative on selected symbol slicing results for synchronizing data fields in a digita |
February 11, 2003 |
| A digital television signal receiver includes a bin amplitude comparator for symbol decoding and match filtering to recover data synchronizing information from selected bin amplitude comparator responses generated during data slicing. The bin amplitude comparator concurrently supplies |
| 6519295 |
VSB DTV receiver with real-only digital synchrodyne to recover baseband symbol code |
February 11, 2003 |
| A radio receiver for vestigial sideband digital modulation, such as used for transmitting digital television signals, employs real-only digital synchrodyne circuitry for synchrodyning a real digital carrier with digitized final intermediate-frequency signal to generate an in-phase sy |
| 6512555 |
Radio receiver for vestigal-sideband amplitude-modulation digital television signals |
January 28, 2003 |
| Apparatus for reproducing data from a selected digital television signal, transmitted in packet form as vestigial-sideband (VSB) amplitude-modulation (AM) of a carrier, has a tuner for selecting a digital television signal and converting it to a final intermediate-frequency signal, w |
| 6507626 |
Bandpass phase tracker that automatically samples at prescribed carrier phases when digitizing V |
January 14, 2003 |
| A bandpass phase tracker automatically samples at prescribed carrier phases when digitizing a vestigial-sideband intermediate-frequency signal, which VSB I-F signal is modulated in accordance with a baseband symbol code of a prescribed symbol frequency. Heterodyning circuitry mixes oscil |
| 6496230 |
Digital TV signal receiver with direct conversion from UHF I-F to Low-Band I-F before digital de |
December 17, 2002 |
| A plural-conversion digital television signal receiver that embodies the invention upconverts digital television signal from a selected television channel to a UHF initial I-F signal. After image-rejection filtering there is a single-step downconversion of the initial UHF first I-F signa |
| 6496229 |
TV receiver using read-only memory shared during VSB and QAM reception for synchrodyning I-F sig |
December 17, 2002 |
| In a digital TV receiver a single digital complex multiplier is used for digitally synchrodyning digital intermediate-frequency signal to baseband both during the reception of VSB digital television signals and during the reception of QAM digital television signals. The component digital |
| 6480236 |
Envelope detection of PN sequences accompanying VSB signal to control operation of QAM/VSB DTV r |
November 12, 2002 |
| The data field synchronization segment as symbol coded for VSB transmission comprises pseudo-random noise (PN) sequence information that can be detected in a QAM/VSB DTV signal receiver using an envelope detector responsive to final intermediate-frequency signal and a match filter for |
| 6480233 |
NTSC co-channel interference detectors responsive to received Q-channel signals in digital TV si |
November 12, 2002 |
| An NTSC co-channel interference detector (44) detects the presence of an interfering NTSC signal in the received Q-channel signal that is orthogonal to the received I-channel signal, rather than detecting the presence of an interfering NTSC signal in the received I-channel signal. By |
| 6449325 |
Circuitry operative on selected symbol slicing results for synchronizing data fields in a digita |
September 10, 2002 |
| A digital television signal receiver includes a bin amplitude comparator for symbol decoding and match filtering to recover data synchronizing information from selected bin amplitude comparator responses generated during data slicing. The bin amplitude comparator concurrently supplies |
| 6445425 |
Automatic fine tuning of receiver for digital television signals |
September 3, 2002 |
| In a superheterodyne radio receiver designed for DTV reception, the IF amplifier chain for the VSB data modulation includes filtering having selective response to different portions of a received DTV signal, as translated to intermediate frequencies by a first detector. There is auto |
| 6441843 |
Suppression of effects of co-channel NTSC interference artifacts upon digital TV receiver adapti |
August 27, 2002 |
| Adaptive equalizers for digital TV receivers in which the filter parameters are adjusted by decision-feedback are followed in cascade by filters for suppressing unwanted demodulation artifacts of NTSC co-channel interference. The decision-feedback signals are derived from the responses |
| 6426780 |
DTV receiver with low-band final I-F signal filtered for suppressing co-channel interfering NTSC |
July 30, 2002 |
| A digital television receiver converts very-high-frequency intermediate-frequency digital television signal to a band with uppermost frequency in the lower portion of the high-frequency range. This facilitates RLC analog filtering, such as a Butterworth-Thomson-transition filter or a |
| 6421403 |
Baseband equalization of quadrature-phase as well as in-phase synchrodyne results in digital rad |
July 16, 2002 |
| A bandpass tracking demodulator for digital radio signals, such as DTV signals, provides an in-phase baseband demodulation result which is subjected to equalization and ghost-cancellation filtering before symbol decoding. The bandpass tracking demodulator also provides a quadrature-p |
| 6384858 |
Suppression of co-channel NTSC interference artifacts when extracting training signal for a DTV |
May 7, 2002 |
| A digital television receiver has an equalizer filter and demodulates received ATSC digital television signal to recover a baseband signal. The ATSC digital television signal is subject to being accompanied at times by a co-channel NTSC analog television signal, which gives rise to u |
| 6380969 |
DTV receiver symbol decoding circuitry with co-channel NTSC artifacts suppression filter before |
April 30, 2002 |
| A data slicer for use in a digital television signal receiver in a television set or in a digital video recorder includes digital filtering for suppressing artifacts of NTSC co-channel interference in the symbol coding offered for data slicing. The artifacts are suppressed by combining |
| 6377312 |
Adaptive fractionally spaced equalizer for received radio transmissions with digital content, su |
April 23, 2002 |
| In a radio receiver for digital transmissions, an adaptive channel equalizer is clocked at a sampling rate higher than symbol rate by a factor k and employs decision feedback for adjusting the coefficients of its component filters. The channel equalizer response as supplied at the sa |
| 6351290 |
Television receiver with separate I-F amplifiers for VSB and QAM digital TV signals that are dig |
February 26, 2002 |
| A radio receiver includes first and second intermediate-frequency amplifier chains respectively supplying first and second final intermediate-frequency responses to a digital television (DTV) signal selected for reception; first and second analog-to-digital converters for digitizing |
| 6313885 |
DTV receiver with baseband equalization filters for QAM signal and for VSB signal which employ c |
November 6, 2001 |
| During the reception of VSB DTV signal, the channel equalizer for a QAM/VSB DTV signal receiver the equalizer is operated to equalize only the real sample stream of VSB symbol code, rather than being operated as a complex equalizer. During the reception of QAM DTV signal, the real sample |
| 6313882 |
TV reception apparatus using same ghost-cancellation circuitry for receiving different types of |
November 6, 2001 |
| Television signal reception apparatus for receiving a television signal selected from among transmitted television signals of different types includes a respective receiver portion for each of the different types. Responsive to its respective type of television signal being received, |
| 6307595 |
NTSC/DTV reception apparatus automatically conditioned for NTSC signal reception responsive to 4 |
October 23, 2001 |
| Television signal reception apparatus for receiving a television signal selected from among transmitted television signals of different types includes a respective receiver portion for each of the different types. The current reception or non-reception of NTSC signal is detected by a |
| 6301312 |
Bandpass phase tracker with hilbert transformation before analog-to-digital conversion |
October 9, 2001 |
| The tuner in a digital TV receiver converts received signal to a penultimate intermediate-frequency signal. Penultimate local oscillations are supplied in a first phasing and in a second phasing in quadrature therewith, for heterodyning with the penultimate IF signal in first and sec |
| 6300984 |
Ghost-cancellation reference signals using spaced PN sequences |
October 9, 2001 |
| Training signal for channel equalization is located in the initial data segment of each DTV data field or in the nineteenth scan line of each NTSC field. The training signal comprises a pseudo-random noise sequence near the conclusion of the initial data segment of each DTV data field or |
| 6211924 |
Decimation of baseband DTV signal prior to channel equalization in digital television signal rec |
April 3, 2001 |
| A radio receiver uses the same tuner for receiving a selected digital television (DTV) signal, irrespective of whether it is a quadrature-amplitude-modulation (QAM) or a vestigial sideband (VSB) signal. The final IF signal is digitized at a rate that is a multiple of both the symbol |
| 6201564 |
Method of operating the channel equalizer in a receiver for DTV signals subject to co-channel NT |
March 13, 2001 |
| A DTV signal receiver includes an adaptive channel equalization filter, a comb filter for suppressing artifacts of co-channel NTSC interference, and an intersymbol-interference suppression filter compensating for the intersymbol interference introduced by the comb filter. The adaptation |
| 6188441 |
Detection of PN sequences accompanying VSB signal to control operating mode of QAM/VSB DTV signa |
February 13, 2001 |
| The data field synchronization segment as symbol coded for VSB transmission comprises pseudo-random noise (PN) sequence information that can be detected using a match filter in a QAM/VSB DTV signal receiver. The data field synchronization segment as symbol coded for QAM transmission does |
| 6184942 |
Adaptively receiving digital television signals transmitted in various formats |
February 6, 2001 |
| Methods for operating an adaptive receiver for receiving a selected DTV signal, which can be either a quadrature-amplitude-modulation (QAM) signal or a vestigial sideband (VSB) signal. The adaptive receiver includes adaptive symbol decoding circuitry for adaptively decoding baseband sign |
| 6184921 |
Method for transmitting VSB digital TV with carrier frequency near co-channel NTSC audio carrier |
February 6, 2001 |
| An N-level digitally encoded signal at a symbol rate f.sub.s substantially equal to three times the NTSC color subcarrier frequency, N being a plural integer, modulates a carrier signal of a frequency within a few hundred kilocycles of the NTSC audio carrier, for transmission through a c |
| 6137545 |
Reception mode control in radio receivers for receiving both VSB and QAM digital television sign |
October 24, 2000 |
| A radio receiver uses the same tuner for receiving a selected wideband digital signal of at least a few megahertz bandwidth, such as a digital television (DTV) signal, irrespective of whether it is a quadrature-amplitude-modulation (QAM) or a vestigial sideband (VSB) signal accompani |
| 6124898 |
Digital television receiver with equalization performed on digital intermediate-frequency signal |
September 26, 2000 |
| A digital television signal receiver in a television set or in a digital video recorder digitizes received digital television signal as converted in frequency to a final intermediate-frequency band close to baseband, then performs equalization filtering on the digitized signal before |
| 6118495 |
Training signal in plural PN sequences near beginnings of data segments of DTV signal or scan li |
September 12, 2000 |
| Training signal for channel equalization is located in the initial data segment of each DTV data field and in the nineteenth scan line of each NTSC field. Arranging for training signal separated from plural PN sequences near the beginnings of the initial data segments of DTV data fie |
| 6108049 |
Circuitry operative on symbol decoding results for synchronizing data fields in a digital televi |
August 22, 2000 |
| A digital television signal receiver includes a data slicer for symbol decoding and match filtering to recover data synchronizing information from the symbol decoding results. The match filtering comprises a shift register for receiving as serial input thereto the parallel-bit-groups of |
