Patents by Inventor Christian Dubuc
Christian Dubuc 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).
-
Patent number: 8213543Abstract: A transmitter (102) generates a first set of data symbols and a first pilot symbol (601) at a first time, and a second set of data symbols and a second pilot symbol (602) at a different, second time. The first (601) and second (602) pilot symbols are each represented by first (701) and second (702) pilot carriers, respectively, located at first (703) and second (704) predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (601), the first (701) and second (702) pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (602), the first (701) and second (702) pilot carriers have third and fourth predetermined values, respectively.Type: GrantFiled: May 10, 2010Date of Patent: July 3, 2012Assignee: Rockstar Bidco, LPInventors: Christian Dubuc, Daniel Boudreau, William R. Kirkland
-
Patent number: 7869538Abstract: A transmitter (102) generates a first set of data symbols and a first pilot symbol (601) at a first time, and a second set of data symbols and a second pilot symbol (602) at a different, second time. The first (601) and second (602) pilot. symbols are each represented by first (701) and second (702) pilot carriers, respectively, located at first (703) and second (704) predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (601), the first (701) and second (702) pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (602), the first (701) and second (702) pilot carriers have third and fourth predetermined values, respectively.Type: GrantFiled: July 23, 2007Date of Patent: January 11, 2011Assignee: Nortel Networks LimitedInventors: Christian Dubuc, Daniel Boudreau, William R. Kirkland
-
Publication number: 20100220825Abstract: A transmitter (102) generates a first set of data symbols and a first pilot symbol (601) at a first time, and a second set of data symbols and a second pilot symbol (602) at a different, second time. The first (601) and second (602) pilot symbols are each represented by first (701) and second (702) pilot carriers, respectively, located at first (703) and second (704) predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (601), the first (701) and second (702) pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (602), the first (701) and second (702) pilot carriers have third and fourth predetermined values, respectively.Type: ApplicationFiled: May 10, 2010Publication date: September 2, 2010Applicant: NORTEL NETWORKS LIMITEDInventors: CHRISTIAN DUBUC, DANIEL BOUDREAU, WILLIAM R. KIRKLAND
-
Patent number: 7486735Abstract: The present invention divides the available sub-carriers in an OFDM symbol window into N groups of sub-carriers wherein each group will be associated with sub-bands. In one embodiment, the sub-carriers in a group are spread throughout the range of sub-carriers to improve frequency diversity, and the sub-carriers assigned to any one group are separated by a constant offset. The sub-carriers in the group may be offset by an integer power of two. Within each group, sub-bands are defined using frequency hopping patterns among sub-carriers in the group from one OFDM symbol window to another. A pseudo-random pattern may be employed for sub-carrier mapping from one OFDM symbol window to the next to effectively distribute the sub-bands across the selected band of sub-carriers for the group.Type: GrantFiled: February 26, 2004Date of Patent: February 3, 2009Assignee: Nortel Networks LimitedInventors: Christian Dubuc, Colin Brown, Daniel Boudreau
-
Patent number: 7428270Abstract: Disclosed is a unique system and method for recognizing the type of modulation embedded in an unknown complex baseband signal, comprising a receiver section for extracting the complex baseband signal from a modulated signal having a carrier frequency, and comprising an orderly series of signal processing functions for (a) estimating the bandwidth of the unknown signal, (b) removing the out-of-band noise and correcting gross carrier frequency errors, (c) discriminating between constant envelope and irregular envelope signals, (d) estimating and correcting residual carrier frequency errors, (e) classifying a constant envelope signal into one of the following modulation formats: {Continuous Wave (CW), Frequency Modulation (FM), Frequency Shift Keying (FSK)}, and (f) classifying an irregular envelope signal into one of the following modulation formats: {Amplitude Modulation (AM), Double Sideband Suppressed Carrier (DSB-SC), Binary Shift Keying (BPSK), Quaternary Phase Shift Keying (QPSK), ?/4-shifted QPSK, M-aryType: GrantFiled: February 15, 2000Date of Patent: September 23, 2008Inventors: Christian Dubuc, Daniel Boudreau
-
Patent number: 7388847Abstract: The present invention provides an improved channel quality indicator indicia for OFDM communication environments. In addition to taking into consideration carrier-to-interference ratios, the present invention also takes into consideration the degree to which the channel response varies among the sub-carriers throughout the OFDM frequency band. The carrier-to-interference ratio and the degree of channel response variation are directly or indirectly used by a base station to select coding and modulation schemes for transmissions from the base station to the mobile terminal reporting these factors. Further, scheduling of data sent to the mobile terminal and other mobile terminals competing for the same channel resources may also be based in part on the carrier-to-interference ratio and the degree to which the channel response varies.Type: GrantFiled: October 3, 2003Date of Patent: June 17, 2008Assignee: Nortel Networks LimitedInventors: Christian Dubuc, Jason Robert Duggan, Peiying Zhu
-
Patent number: 7356089Abstract: A rotation by a phase offset is applied to symbols to be transmitted by one antenna relative to symbols to be transmitted from another antenna in a wireless communication system employing multi-element antennas at the transmitter. Such a phase offset allows the functionality of a MIMO system to be maintained when a MIMO channel degenerates. Advantageously, a MIMO system using the new signal design may provide a level of performance in a rich-scattering environment that is equivalent to a MIMO system using a known signal design. Furthermore, a MIMO system employing embodiments of the present invention may show significantly improvements in robustness over conventional MIMO systems.Type: GrantFiled: September 5, 2003Date of Patent: April 8, 2008Assignee: Nortel Networks LimitedInventors: Ming Jia, Peiying Zhu, Wen Tong, Christian Dubuc
-
Publication number: 20070263667Abstract: A transmitter (102) generates a first set of data symbols and a first pilot symbol (601) at a first time, and a second set of data symbols and a second pilot symbol (602) at a different, second time. The first (601) and second (602) pilot. symbols are each represented by first (701) and second (702) pilot carriers, respectively, located at first (703) and second (704) predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (601), the first (701) and second (702) pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (602), the first (701) and second (702) pilot carriers have third and fourth predetermined values, respectively.Type: ApplicationFiled: July 23, 2007Publication date: November 15, 2007Inventors: Christian Dubuc, Daniel Boudreau, William Kirkland
-
Patent number: 7251291Abstract: A transmitter (102) generates a first set of data symbols and a first pilot symbol (601) at a first time, and a second set of data symbols and a second pilot symbol (602) at a different, second time. The first (601) and second (602) pilot symbols are each represented by first (701) and second (702) pilot carriers, respectively, located at first (703) and second (704) predetermined sample frequencies, respectively, in a channel bandwidth. For the first pilot symbol (601), the first (701) and second (702) pilot carriers have first and second predetermined values, respectively. For the second pilot symbol (602), the first (701) and second (702) pilot carriers have third and fourth predetermined values, respectively.Type: GrantFiled: December 18, 2002Date of Patent: July 31, 2007Assignee: Nortel Networks LimitedInventors: Christian Dubuc, Daniel Boudreau, William R. Kirkland
-
Publication number: 20050053169Abstract: A rotation by a phase offset is applied to symbols to be transmitted by one antenna relative to symbols to be transmitted from another antenna in a wireless communication system employing multi-element antennas at the transmitter. Such a phase offset allows the functionality of a MIMO system to be maintained when a MIMO channel degenerates. Advantageously, a MIMO system using the new signal design may provide a level of performance in a rich-scattering environment that is equivalent to a MIMO system using a known signal design. Furthermore, a MIMO system employing embodiments of the present invention may show significantly improvements in robustness over conventional MIMO systems.Type: ApplicationFiled: September 5, 2003Publication date: March 10, 2005Inventors: Ming Jia, Peiying Zhu, Wen Tong, Christian Dubuc
-
Publication number: 20050041622Abstract: The present invention provides an improved channel quality indicator indicia for OFDM communication environments. In addition to taking into consideration carrier-to-interference ratios, the present invention also takes into consideration the degree to which the channel response varies among the sub-carriers throughout the OFDM frequency band. The carrier-to-interference ratio and the degree of channel response variation are directly or indirectly used by a base station to select coding and modulation schemes for transmissions from the base station to the mobile terminal reporting these factors. Further, scheduling of data sent to the mobile terminal and other mobile terminals competing for the same channel resources may also be based in part on the carrier-to-interference ratio and the degree to which the channel response varies.Type: ApplicationFiled: October 3, 2003Publication date: February 24, 2005Applicant: NORTEL NETWORKS LIMITEDInventors: Christian Dubuc, Jason Duggan, Peiying Zhu
-
Patent number: 6812092Abstract: A Dynamic Random Access Memory is fabricated in a semiconductor body of a first conductivity type in which there have been formed an array of memory cells which each include a trench capacitor and a vertical Insulated Gate Field Effect Transistor (IGFET). Each IGFET includes first and second output regions of a second opposite conductivity type and a gate which is separated from a surface of the semiconductor body by a gate dielectric layer. A gate electrode connected to the gate is formed using a Damascene process with insulating sidewall spacer regions being formed before the gate electrode is formed. Borderless contacts, which are self aligned, are made to the first output regions of each transistor using a Damascene process.Type: GrantFiled: December 19, 2000Date of Patent: November 2, 2004Assignee: Infineon TechnologiesInventors: Mihel Seitz, Michael Wise, Christian Dubuc
-
Publication number: 20040190640Abstract: The present invention divides the available sub-carriers in an OFDM symbol window into N groups of sub-carriers wherein each group will be associated with sub-bands. In one embodiment, the sub-carriers in a group are spread throughout the range of sub-carriers to improve frequency diversity, and the sub-carriers assigned to any one group are separated by a constant offset. The sub-carriers in the group may be offset by an integer power of two. Within each group, sub-bands are defined using frequency hopping patterns among sub-carriers in the group from one OFDM symbol window to another. A pseudo-random pattern may be employed for sub-carrier mapping from one OFDM symbol window to the next to effectively distribute the sub-bands across the selected band of sub-carriers for the group.Type: ApplicationFiled: February 26, 2004Publication date: September 30, 2004Applicant: NORTEL NETWORKS LIMITEDInventors: Christian Dubuc, Colin Brown, Daniel Boudreau
-
Publication number: 20040033659Abstract: A Dynamic Random Access Memory is fabricated in a semiconductor body of a first conductivity type in which there have been formed an array of memory cells which each include a trench capacitor and a vertical Insulated Gate Field Effect Transistor (IGFET). Each IGFET includes first and second output regions of a second opposite conductivity type and a gate which is separated from a surface of the semiconductor body by a gate dielectric layer. A gate electrode connected to the gate is formed using a Damascene process with insulating sidewall spacer regions being formed before the gate electrode is formed. Borderless contacts, which are self aligned, are made to the first output regions of each transistor using a Damascene process.Type: ApplicationFiled: December 19, 2000Publication date: February 19, 2004Inventors: Mihel Seitz, Michael L. Wise, Christian Dubuc
-
Patent number: 4933888Abstract: Process for the digitization and linearization of a quasi-sinusoidal periodic characteristic transducer and the corresponding apparatus.The process consist of measuring a variation (.DELTA..phi..sub.x) of a signal (.phi..sub.x) received by the transducer in accordance with the following operations:superimposing on the signal to be measured a first auxiliary periodic signal (.phi..sub.I) of frequency F.sub.I higher than the highest frequency of the range of the signal to be measured and of amplitude substantially equal to .phi..sub.o /2 and a second auxiliary signal constituted by a periodic linear ramp (.phi..sub.R) of a frequency f.sub.R well below F.sub.I and of amplitude .phi..sub.1, the transducer thus receiving a composite signal constituted by the signal to be measured, the first auxiliary signal and the second auxiliary signal;deducing from the signal supplied by the transducer, two periodic signal V.sub.C1 and V.sub.C2, of period .phi..sub.Type: GrantFiled: April 25, 1988Date of Patent: June 12, 1990Assignee: Commissariat a l'Energie AtomiqueInventors: Daniel Bloyet, Christian Dubuc, Denis Duret, Jacques Lepaisant, Didier Robbes, Khalid Benhida