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21.发明专利
公开(公告)号：CA2308973C
公开(公告)日：2004-08-17
申请号：CA2308973
申请日：2000-05-19
Applicant: LUCENT TECHNOLOGIES INC
Inventor： SUNDBERG CARL-ERIK WILHELM , LANEMAN JERRY NICHOLAS
Abstract: Techniques for processing received information in a communication system, su ch that performance is significantly improved in the presence of certain types of interference. In an illustrative embodiment, first and second digital sidebands are transmitted on either side of an FM or AM host carrier signal in a hybrid in-band on-channel (HIBO C) digital audio broadcasting (DAB) system. The compressed digital audio information in the sidebands is encoded using an outer code, e.g., a cyclic redundancy code (CRC), and an inner code, e.g., a complementary punctured pair convolutional (CPPC) code. A receiver generates an error indicator based at least in part on a first decoding of t he received information. The error indicator characterizes interference associated with at least one of the digital sidebands. The receiver then generates at least one alternative decoding of the received information if the error indicator has a designated characteristic. For example, the receiver may generate the alternative decoding by eliminating from consideration in the receiver decoding process a designated portion of at least one of the digita l sidebands. The error indicator may be indicative of the presence or absence of a first adjacent interference signal of a particular level within a frequency band associated withone of the sidebands, and may be based on, e.g., a signal-to-noise ratio measurement generated from a pilot tone associated with a given sideband, and/or an error flag generated using the C RC outer code. Portions of the given sideband may be eliminated from consideration via successive erasures of sideband components, i.e., subbands, thereby resulting in an increase in the effective code rate of the inner code.
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22.发明专利
公开(公告)号：CA2327772A1
公开(公告)日：2001-06-15
申请号：CA2327772
申请日：2000-12-07
Applicant: LUCENT TECHNOLOGIES INC
Abstract: Improved error screening techniques for use in processing digital audio or other types of information received in a digital communication system. Control information associated with a given packet of the received information is identified and compared with a decoding requirement of the packet, in order to control the generation of an error indicator for the packet. More particularly, the error indicator may be generated in response to an inconsistency between the control information and the decoding requirement. For example, the control information may include an indication of packet length that can be compared to a number of bits required to decode the corresponding packet, with any inconsistency between the packet length indication and the number of required bits leading to the generation of an error flag for the packet. The invention is particularly we ll- suited for use in the processing of encoded digital audio information received in a hybrid in- band on- channel (HIBOC) digital audio broadcasting (DAB) system, but is also applicable to other types of information and other types of communication systems.
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公开(公告)号：CA2322715A1
公开(公告)日：2001-04-21
申请号：CA2322715
申请日：2000-10-10
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LOU HUI-LING , SUNDBERG CARL-ERIK WILHELM
Abstract: A method for providing packet loss recovery in a data packet-based network used for real-time multimedia communications. In accordance with a first illustrative embodiment of the present invention, the information payload associated with a given data packet k is identically copied and appended to data packet k+w (i. e., the information payload is repeated with a delay of w transmitted packets). More generally, the present invention provides a method of coding a sequence of data packets representin g a continuous stream of information, each data packet comprising a set of paylo ad information representative of a segment of the stream of information corresponding thereto, the method comprising the steps of coding a first data packet for transmission, wherein the encoded first data packet comprises a first set of payload information representativ e of a first segment of the stream of information; and coding a second data packet subsequent to the first data packet in the sequence for transmission, wherein the encoded cond data packet comprises a second set of payload information representative of a second segment of the stream of information subsequent to the first segment of the stream of information, and wherein the encoded second data packet further comprises an additional set o f payload information, the additional set of payload information also representative o f the first segment of the stream of information, but not representative of other segmen ts of the stream of information.
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公开(公告)号：CA2217429C
公开(公告)日：2001-04-17
申请号：CA2217429
申请日：1997-10-06
Applicant: LUCENT TECHNOLOGIES INC
Inventor： PAPADOPOULOS HARALABOS C , SUNDBERG CARL-ERIK WILHELM
IPC: H03H21/00 , H03C3/00 , H04B1/66 , H04H20/30 , H04J1/00 , H04J1/12 , H04J9/00 , H04J11/00 , H04L27/10 , H04L27/32 , H04B1/16
Abstract: In a system for simulcasting a digitally modulated signal and an analog FM signal over the same FM frequency band, the composite signal is received and applied to a conventional FM receiver, and a digital receiver in accordance with the invention. An extended Kalman filter is employed in the digital receiver to estimate the analog FM signal based on a version of the recovered FM signal from the FM receiver, and a discrete version of the composite signal whose spectrum has been translated and is at an intermediate carrier frequency. The estimated FM signal, which is in a discrete form, is subtracted from the discrete version of the composite signal. The resulting signal, which is an estimated version of the digitally modulated signal, is demodulated to recover the digital data as transmitted.
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公开(公告)号：CA2302608A1
公开(公告)日：2000-09-29
申请号：CA2302608
申请日：2000-03-28
Applicant: LUCENT TECHNOLOGIES INC
Inventor： SUNDBERG CARL-ERIK WILHELM , SINHA DEEPEN , MANSOUR DAVID
IPC: H04L1/00 , H04B1/04 , H04H20/30 , H04H60/07 , H04J1/00 , H04J13/00 , H04L5/02 , H04L5/00 , H04H5/00
Abstract: Methods and apparatus for processing information, e.g., audio, speech, video or image information, for transmission in a communication system. In an illustrative embodiment, a set of bit streams are generated from an audio information signal. The set of bit streams may be, e.g., a total of four bit streams generated by separating each of two multiple description bit streams, corresponding to separate representations of the audio information signal, into first and second class bit streams. The first and second class bit streams associated with the first multiple description bit stream may then be transmitted in respective first and second subbands of a first sideband of an FM host carrier, while the first and second class bit streams associated with the second multiple description bit stream are transmitted in respective first and second subbands of a second sideband of the FM host carrier. The first class bit streams may be provided with a different level of error protection than the second class bit streams, e.g., by utilizing different portions of a non-uniform power profile for the corresponding subbands, or by placement of the bit streams in subbands having different susceptibility to interference. Delay may be introduced between at least a subset of the bit streams in order to provide improved performance, e.g., in the presence of fading.
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Patent Agency Ranking26.发明专利
公开(公告)号：CA2266114A1
公开(公告)日：1999-10-22
申请号：CA2266114
申请日：1999-03-17
Applicant: LUCENT TECHNOLOGIES INC
Inventor： CHEN BRIAN , SUNDBERG CARL-ERIK WILHELM
IPC: H04L27/00 , H04B1/04 , H04H20/00 , H04J11/00 , H04L5/02 , H04L27/36 , H04B3/06 , H04B7/005 , H04L27/04
Abstract: In a communications system implementing an in-band on channel AM (IBOC-AM) (also known as "hybrid IBOC-AM") scheme, digitally modulated signals are transmitted in a 30 kHz digital band centered at an analog host AM carrier frequency f c. The host AM carrier is assigned to the geographic area served by the communications system for AM radio broadcast. It is likely that a similar IBOC-AM scheme is implemented in an adjacent area which is assigned a second analog host AM carrier having a frequency which is either 20 kHz higher or lower than f c. In that case, the transmission of the digitally modulated signals are interfered by a similar transmission in the adjacent area. The interference is known as "second adjacent channel interference." To reduce such interference, selected power profiles in accordance with the invention are used to allocate the relative transmission power to the digitally modulated signals in the digital band.
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公开(公告)号：DE69841744D1
公开(公告)日：2010-08-12
申请号：DE69841744
申请日：1998-03-11
Applicant: LUCENT TECHNOLOGIES INC
Inventor： CHEN BRIAN , SUNDBERG CARL-ERIK WILHELM
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公开(公告)号：CA2322715C
公开(公告)日：2005-08-16
申请号：CA2322715
申请日：2000-10-10
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LOU HUI-LING , SUNDBERG CARL-ERIK WILHELM
Abstract: A method for providing packet loss recovery in a data packet-based network used for real-time multimedia communications. In accordance with a first illustrative embodiment of the present invention, the information payload associated with a given data packet k is identically copied and appended to data packet k+w (i. e., the information payload is repeated with a delay of w transmitted packets). More generally, the present invention provides a method of coding a sequence of data packets representin g a continuous stream of information, each data packet comprising a set of paylo ad information representative of a segment of the stream of information corresponding thereto, the method comprising the steps of coding a first data packet for transmission, wherein the encoded first data packet comprises a first set of payload information representativ e of a first segment of the stream of information; and coding a second data packet subsequent to the first data packet in the sequence for transmission, wherein the encoded cond data packet comprises a second set of payload information representative of a second segment of the stream of information subsequent to the first segment of the stream of information, and wherein the encoded second data packet further comprises an additional set o f payload information, the additional set of payload information also representative o f the first segment of the stream of information, but not representative of other segmen ts of the stream of information.
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29.发明专利
公开(公告)号：CA2327772C
公开(公告)日：2005-08-09
申请号：CA2327772
申请日：2000-12-07
Applicant: LUCENT TECHNOLOGIES INC
Abstract: Improved error screening techniques for use in processing digital audio or other types of information received in a digital communication system. Control information associated with a given packet of the received information is identified and compared with a decoding requirement of the packet, in order to control the generation of an error indicator for the packet. More particularly, the error indicator may be generated in response to an inconsistency between the control information and the decoding requirement. For example, the control information may include an indication of packet length that can be compared to a number of bits required to decode the corresponding packet, with any inconsistency between the packet length indication and the number of required bits leading to the generation of an error flag for the packet. The invention is particularly we ll- suited for use in the processing of encoded digital audio information received in a hybrid in- band on-channel (HIBOC) digital audio broadcasting (DAB) system, but is also applicable to other types of information and other types of communication systems.
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30.发明专利
公开(公告)号：CA2296138C
公开(公告)日：2004-08-17
申请号：CA2296138
申请日：2000-01-14
Applicant: LUCENT TECHNOLOGIES INC
Inventor： SINHA DEEPEN , SUNDBERG CARL-ERIK WILHELM
Abstract: The invention provides methods and apparatus for processing information, e.g ., audio, video or image information, for transmission in a communication syste m. In an illustrative embodiment, a multiple program coder encodes a bitstream associated each of the programs, in accordance with a specified bit allocation. An outer code encoder receives the encoded bitstreams from the multiple program coder, and jointly applies an outer code, e.g., a CRC code, RS code, BCH code or other type of linear block code, to subblocks of a subset of the resulting encoded bitstreams. The outer code is applied such that subblocks of each of the encoded bitstreams in the subset of the encoded bitstreams ar e associated with a single outer code block. The number of subblocks associated with a given outer code block may be an integer or non-integer number of code blocks. The invention allows a designated number of program subblocks to share a given outer code block, su ch that outer code error flags can be generated for smaller groups of bits per program tha n would otherwise be possible. An inner code encoder may be used to apply an inner code, e.g., a convolutional code, turbo code or trellis coded modulation, to the resulting outer code blocks.
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