Patents by Inventor Ernest C. Chen
Ernest C. Chen 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).
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Patent number: 7639980Abstract: A system 10 that includes a first satellite 14 at a first orbital slot B includes a first transponder 32 generating a first downlink signal at a first frequency and a second downlink signal at a second frequency. An outdoor unit 50 is directed toward the first satellite 14. The outdoor unit includes a support structure 80 and a reflector 64 coupled to the support structure 80 and reflecting the first downlink signal from a first satellite. A first reflector reflects the second downlink signal from the first satellite. A first feed 66 is coupled to the support structure and receives the first downlink signal. A reflector 72 having frequency selective surface 74 coupled to the support structure 80 reflects the second downlink signal and passes the first downlink signal therethrough. The second feed 70B is coupled to the support structure 80 and receives the second downlink signal reflected from the frequency selective surface 74.Type: GrantFiled: November 21, 2006Date of Patent: December 29, 2009Assignee: The DIRECTV Group, Inc.Inventors: Gustave R. Stroes, Patrick J. Loner, Joseph Santoru, Ernest C. Chen, Navid Motamed
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Publication number: 20090224824Abstract: Systems and methods for characterizing amplifiers. A system for characterizing an amplifier in accordance with the present invention comprises a Gaussian signal source for generating a signal in the frequency domain, a notch filter, coupled to the Gaussian Noise source, wherein the notch filter has a notch at a specified frequency and a frequency bandwidth, the frequency bandwidth encompassing the specified frequency, an Inverse Fast Fourier Transform device, coupled to an output of the notch filter, a normalization device, coupled to the Inverse Fast Fourier Transform device, an amplifier under test, coupled to the normalization device, for amplifying the signal generated by the Gaussian signal source, and a measurement device, coupled to an output of the amplifier, for measuring a power output of the amplifier in the frequency bandwidth and a noise output at the specified notch frequency, and for calculating the ratio between the power output and the noise output.Type: ApplicationFiled: April 9, 2009Publication date: September 10, 2009Applicant: The DIRECTV Group, Inc.Inventors: Guangcai Zhou, Tung-Sheng Lin, Dennis Lai, Joseph Santoru, Ernest C. Chen, Shamik Maitra, Cecilia Comeaux
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Patent number: 7583728Abstract: A method and apparatus for equalizing digital data signals is disclosed. The method comprises the steps of demodulating and decoding an input signal having input data to produce a data output, remodulating the data output to produce a training sequence including an idealized input signal, wherein the training sequence is comprised of adjacent symbols in the input data, and generating equalizer parameters from the training sequence. The apparatus comprises a demodulator (for demodulating an input signal to produce a data output), a modulator communicatively coupled to the demodulator (for remodulating the data output to produce a training sequence including an idealized input signal wherein the training sequence is comprised of adjacent symbols in the input data), and a parameter generation module communicatively coupled to the modulator (for generating equalizer parameters from the training sequence).Type: GrantFiled: January 22, 2007Date of Patent: September 1, 2009Assignee: The DIRECTV Group, Inc.Inventors: Ernest C. Chen, Tung-Sheng Lin, Weizheng Wang, William C. Lindsey
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Patent number: 7577213Abstract: A method and receiver systems for demodulating and decoding a hierarchically modulated signal, e.g. an 8PSK signal, are disclosed. An exemplary method includes demodulating and processing (502) the hierarchically modulated signal (202) to produce symbols (212) from the first modulation at the first hierarchical level, applying information (504) from a plurality of the symbols from the first modulation at the first hierarchical level in subtracting (214) from the demodulated hierarchically modulated signal to obtain the second modulation at the second hierarchical level and processing (506) the second modulation at the second hierarchical level to produce second symbols (222) from the demodulated second signal. The hierarchically modulated signal comprises a non-uniform 8PSK signal. Applying the information from the plurality of the symbols from the first modulation can be achieved by applying the symbols after error correction.Type: GrantFiled: July 21, 2008Date of Patent: August 18, 2009Assignee: The DIRECTV Group, Inc.Inventors: Ernest C. Chen, Joseph Santoru
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Publication number: 20090182796Abstract: A method for generating a set of random numbers with statistics represented by a cumulative density function includes generating a set of uniformly spaced samples between an upper limit and a lower limit. Each of the uniformly spaced samples are then mapped to a corresponding value on a cumulative density function curve. The set of uniformly spaced samples are then scrambled to randomize the samples. Companding may also be incorporated in the sample generation process.Type: ApplicationFiled: November 21, 2008Publication date: July 16, 2009Applicant: The DIRECTV Group, Inc.Inventors: Ernest C. Chen, Paul R. Anderson, Joseph Santoru, Tammy G. Liu
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Publication number: 20090175327Abstract: A method and apparatus for equalizing digital data signals is disclosed. The method comprises the steps of demodulating and decoding an input signal having input data to produce a data output, remodulating the data output to produce a training sequence including an idealized input signal, wherein the training sequence is comprised of adjacent symbols in the input data, and generating equalizer parameters from the training sequence. The apparatus comprises a demodulator (for demodulating an input signal to produce a data output), a modulator communicatively coupled to the demodulator (for remodulating the data output to produce a training sequence including an idealized input signal wherein the training sequence is comprised of adjacent symbols in the input data), and a parameter generation module communicatively coupled to the modulator (for generating equalizer parameters from the training sequence).Type: ApplicationFiled: March 13, 2009Publication date: July 9, 2009Applicant: The DIRECTV Group, Inc.Inventors: Ernest C. Chen, Tung-sheng Lin, Weizheng Wang, William C. Lindsey
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Patent number: 7551736Abstract: Methods and apparatuses for minimizing co-channel interference in communications systems are disclosed. A method in accordance with the present invention comprises scrambling a first header of the first signal using a first scrambling code, scrambling a second header of the second signal using a second scrambling code, and transmitting the first signal and the second signal with the scrambled first header and the scrambled second header over different channels of the communication system.Type: GrantFiled: April 11, 2005Date of Patent: June 23, 2009Assignee: The DIRECTV Group, Inc.Inventors: Lin-Nan Lee, Feng-Wen Sun, Adam Von Ancken, Joseph Santoru, Ernest C. Chen, Shamik Maitra, Dennis Lai, Guangcai Zhou, Tung-Sheng Lin
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Patent number: 7535292Abstract: Systems and methods for characterizing amplifiers. A system for characterizing an amplifier in accordance with the present invention comprises a Gaussian signal source for generating a signal in the frequency domain, a notch filter, coupled to the Gaussian Noise source, wherein the notch filter has a notch at a specified frequency and a frequency bandwidth, the frequency bandwidth encompassing the specified frequency, an Inverse Fast Fourier Transform device, coupled to an output of the notch filter, a normalization device, coupled to the Inverse Fast Fourier Transform device, an amplifier under test, coupled to the normalization device, for amplifying the signal generated by the Gaussian signal source, and a measurement device, coupled to an output of the amplifier, for measuring a power output of the amplifier in the frequency bandwidth and a noise output at the specified notch frequency, and for calculating the ratio between the power output and the noise output.Type: GrantFiled: October 11, 2007Date of Patent: May 19, 2009Assignee: The DIRECTV Group, Inc.Inventors: Guangcai Zhou, Tung-Sheng Lin, Dennis Lai, Joseph Santoru, Ernest C. Chen, Shamik Maitra, Cecilia Comeaux
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Patent number: 7529312Abstract: Systems and methods are disclosed for applying layered modulation to an 8-VSB signal as used in the Advanced Television Systems Committee (ATSC) digital television signal. A system for transmitting the layered signal includes a first antenna for transmitting an upper layer signal comprising an 8-VSB signal and a second antenna for transmitting a lower layer signal. A layered modulation signal comprises the upper layer signal and the lower layer signal both interfering in a common frequency band. At least one receiver demodulates the upper layer signal directly from the layered modulation signal and demodulates the lower layer signal after subtracting the upper layer signal from the layered modulation signal. The second antenna can have a selectively limited range so that the lower layer signal does not interfere with the upper layer signal in a range where the lower layer signal could not be demodulated.Type: GrantFiled: October 24, 2003Date of Patent: May 5, 2009Assignee: The DIRECTV Group, Inc.Inventor: Ernest C. Chen
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Publication number: 20090097589Abstract: A method and apparatus for transmitting and receiving a coded signal having an upper layer signal and a lower layer signal is disclosed. The method comprises the steps of combining the upper layer signal and the lower layer signal, encoding the combined upper layer signal and lower layer signal, delaying the upper layer signal, modulating the delayed upper layer signal, modulating the lower layer signal, transmitting the delayed upper layer signal and transmitting the lower layer signal. The apparatus comprises an encoder, for encoding a combined upper layer signal and lower layer signal, a delay, communicatively coupled to the encoder, for delaying the upper layer signal, a first modulator, for modulating the delayed upper layer signal, a second modulator, for modulating the lower layer signal, a transmitter, communicatively coupled to the first modulator, for transmitting the delayed upper layer signal, and a second transmitter, communicatively coupled to the second modulator.Type: ApplicationFiled: December 5, 2008Publication date: April 16, 2009Applicant: THE DIRECTV GROUP, INC.Inventors: ERNEST C. CHEN, Weizheng W. Wang, Guangcai Zhou, Tung-Sheng Lin, Joseph Santoru
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Patent number: 7512189Abstract: A method and apparatus for transmitting and receiving a coded signal having an upper layer signal and a lower layer signal is disclosed. The method comprises the steps of combining the upper layer signal and the lower layer signal, encoding the combined upper layer signal and lower layer signal, delaying the upper layer signal, modulating the delayed upper layer signal, modulating the lower layer signal, transmitting the delayed upper layer signal and transmitting the lower layer signal. The apparatus comprises an encoder, for encoding a combined upper layer signal and lower layer signal, a delay, communicatively coupled to the encoder, for delaying the upper layer signal, a first modulator, for modulating the delayed upper layer signal, a second modulator, for modulating the lower layer signal, a transmitter, communicatively coupled to the first modulator, for transmitting the delayed upper layer signal, and a second transmitter, communicatively coupled to the second modulator.Type: GrantFiled: October 10, 2003Date of Patent: March 31, 2009Assignee: The DIRECTV Group, Inc.Inventors: Ernest C. Chen, Weizheng W. Wang, Guangcai Zhou, Tung-Sheng Lin, Joseph Santoru
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Publication number: 20090073917Abstract: Systems and methods are disclosed for feeder link configurations to layered modulation. One feeder link system employs feeder link spot beam to antennas in distinct coverage areas to enable frequency reuse. Another system employs narrow beam width feeder link antenna to illuminate individual satellites also enabling frequency reuse. Yet another system uses layered modulation in the feeder link. Another feeder link system employs a higher order synchronous modulation for the satellite feeder link than is used in the layered modulation downlink signals.Type: ApplicationFiled: August 12, 2008Publication date: March 19, 2009Applicant: The DIRECTV Group, Inc.Inventors: Paul R. Anderson, Joseph Santoru, Ernest C. Chen
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Publication number: 20090068953Abstract: Methods and apparatuses for minimizing co-channel interference in communications systems are disclosed. A method in accordance with the present invention comprises scrambling a first frame using a first scrambling code, attaching a first header to the first frame to create the first signal, scrambling a second frame using a second scrambling code, attaching a second header to the second frame to create the second signal, and transmitting the first signal and the second signal over different channels of the communication system.Type: ApplicationFiled: October 30, 2008Publication date: March 12, 2009Applicant: The DIRECTV Group, Inc.Inventors: Lin-Nan Lee, Feng-Wen Sun, Adam Von Ancken, Joseph Santoru, Ernest C. Chen, Shamik Maitra, Dennis Lai, Guangcai Zhou, Tung-Sheng Lin
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Patent number: 7502429Abstract: A method and system provide the ability to measure a transmission performance characteristic. A signal is received and equalized. The equalized signal is demodulated and an ideal signal is generated from the demodulated equalized signal. A performance characteristic is the estimated from a difference between the ideal signal and the equalized signal.Type: GrantFiled: October 8, 2004Date of Patent: March 10, 2009Assignee: The DIRECTV Group, Inc.Inventor: Ernest C. Chen
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Patent number: 7502430Abstract: A method and system provide the ability to measure a transmission performance characteristic. A signal is received and demodulated. An ideal signal is generated from the demodulated signal. The received signal is coherently averaged to reduce noise. The performance characteristic is the estimated TWTA nonlinearity from a difference between the coherently averaged ideal signal and received signal.Type: GrantFiled: October 8, 2004Date of Patent: March 10, 2009Assignee: The DIRECTV Group, Inc.Inventor: Ernest C. Chen
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Publication number: 20090052590Abstract: Signals, systems and methods for transmitting and receiving layered modulation for digital signals are presented. A layered signal for transmitting data, comprises a first signal layer including a first carrier and first signal symbols for a first digital signal transmission and a second signal layer including a second carrier and second signal symbols for a second signal transmission disposed on the first signal layer, wherein the layered signal has the first carrier demodulated and first layer decoded to produce the first signal symbols for a first layer transport, the first signal symbols are remodulated and subtracted from the layered signal to produce the second signal layer, and the second signal layer has the second carrier demodulated and decoded to produce the second signal symbols for a second layer transport.Type: ApplicationFiled: October 28, 2008Publication date: February 26, 2009Applicant: The DIRECTV Group, Inc.Inventor: Ernest C. Chen
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Publication number: 20090052503Abstract: Methods and apparatuses for minimizing co-channel interference in communications systems are disclosed. A method in accordance with the present invention comprises shifting a characteristic of the first signal with respect to a like characteristic of the second signal to mitigate co-channel interference, and transmitting the first signal and the second signal over different channels of the communication system.Type: ApplicationFiled: April 14, 2008Publication date: February 26, 2009Applicant: THE DIRECTV GROUP, INC.Inventors: Joseph Santoru, Ernest C. Chen, Shamik Maitra, Dennis Lai, Guangcai Zhou, Tung-Sheng Lin
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Publication number: 20090036086Abstract: Systems for delivering a plurality of broadcast programs where the transmitter and receiver roll-off factors are mismatched. A system in accordance with the present invention comprises a transmitter comprising a modulator, and a plurality of receivers, each receiver in the plurality of receivers receiving the plurality of broadcast programs, each receiver in the plurality of receivers further comprising a demodulator; wherein the modulator has a first root-raised cosine filter having a first roll-off factor and each receiver has a second root-raised cosine filter having a second roll-off factor, the first roll-off factor being smaller than the second roll-off factor.Type: ApplicationFiled: July 31, 2007Publication date: February 5, 2009Applicant: THE DIRECTV GROUP, INC.Inventors: ERNEST C. CHEN, JOSEPH SANTORU, Shamik MAITRA, DENNIS LAI, TUNG-SHENG LIN, GUANGCAI ZHOU
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Patent number: 7483495Abstract: Signals, systems and methods for transmitting and receiving layered modulation for digital signals are presented. A layered signal for transmitting data, comprises a first signal layer including a first carrier and first signal symbols for a first digital signal transmission and a second signal layer including a second carrier and second signal symbols for a second signal transmission disposed on the first signal layer, wherein the layered signal has the first carrier demodulated and first layer decoded to produce the first signal symbols for a first layer transport, the first signal symbols are remodulated and subtracted from the layered signal to produce the second signal layer, and the second signal layer has the second carrier demodulated and decoded to produce the second signal symbols for a second layer transport.Type: GrantFiled: January 16, 2007Date of Patent: January 27, 2009Assignee: The DIRECTV Group, Inc.Inventor: Ernest C. Chen
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Patent number: 7483505Abstract: A method and apparatus for equalizing digital data signals is disclosed. The method comprises the steps of demodulating and decoding an input signal having input data to produce a data output, remodulating the data output to produce a pseudo-training sequence including an idealized input signal, and generating equalizer parameters from the pseudo-training sequence. The apparatus comprises a demodulator for demodulating an input signal to produce a data output, a modulator, communicatively coupled to the demodulator, for remodulating the data output to produce a pseudo-training sequence including an idealized input signal, and a parameter generation module, communicatively coupled to the modulator for generating equalizer parameters from the pseudo-training sequence.Type: GrantFiled: October 22, 2003Date of Patent: January 27, 2009Assignee: The DIRECTV Group, Inc.Inventors: Weizheng W. Wang, Tung-Sheng Lin, Ernest C. Chen, William C. Lindsey