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公开(公告)号：JP2000188590A
公开(公告)日：2000-07-04
申请号：JP32193399
申请日：1999-11-12
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LI QUINN , RAMESH NALLEPILLI S
Abstract: PROBLEM TO BE SOLVED: To guarantee a time difference between I and/or Q scrambling code sequences of a same user and/or a different user by mixing the component of a first complex code sequence with the corresponding component of a second complex code sequence. SOLUTION: On an I route 132, an I mixer 138 mixes or multiplies the I component of a long code sequence with the first component of a second complex code sequence like the I component of a short code sequence and the I component of the complex scrambling code sequence is generated. On a Q route 134, a Q mixer 140 mixes or multiplies a Q long code sequence with the second component of a complex short code sequence like the Q component of the short code sequence and the Q component of the complex scrambling code sequence is generated.
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公开(公告)号：ES2178868T3
公开(公告)日：2003-01-01
申请号：ES99308692
申请日：1999-11-02
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LI QUINN , RAMESH NALLEPILLI S
Abstract: A complex spreading and/or scrambling code sequence ("scrambling code sequence") generation system uses a first complex code sequence having at least two components and a second complex code sequence having at least two components. The components of the first complex code sequence are respectively mixed with the corresponding components of the second complex code sequence to generate the complex scrambling code sequence. In doing so, an offset between the components of the complex scrambling code sequence is achieved for the same and/or different users. For example, the complex spreading code sequence generation system can use a long code generator which produces a long code sequence produced from the inner product of a code vector and a user mask. The long code sequence is provided to an I path and a Q path. To produce a complex long code sequence, the long code sequence on the Q path is delayed to produce a second long code sequence on the Q path or a Q component of the complex long code sequence. On the I path, the I long code sequence or the I component of the complex long code sequence is multiplied with an I component of a short code sequence to produce the I component of the complex scrambling code sequence. On the Q path, the Q long code sequence is multiplied with a Q component of the short code sequence to produce the Q component of the complex scrambling code sequence. As such, the offset between the components of the complex scrambling code sequence between different and/or the same user is at least the period of the short code. The complex scrambling code sequence can be used for spreading, scrambling, de-spreading or de-scrambling an information signal.
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公开(公告)号：CA2266165A1
公开(公告)日：1999-10-21
申请号：CA2266165
申请日：1999-03-18
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RAMESH NALLEPILLI S
Abstract: A wireless telecommunications system is disclosed that mitigates multipath fading through an improvement in transmit diversity. Furthermore, embodiments of the present invention are well-suited for use with all forward channel multiplexing schemes (e.g., frequency-division multiplexing, time-division multiplexing, code-division multiplexing, etc.) and all modulation techniques (e. g. , amplitude modulation, frequency modulation, phase modulation, etc.). An illustrative embodiment of the present invention comprises: a signal inverter for inverting and alternately not-inverting a first signal in accordance with a schedule to create a second signal; a first antenna for transmitting the first signal; and a second antenna for transmitting the second signal.
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公开(公告)号：DE69719886T2
公开(公告)日：2003-11-27
申请号：DE69719886
申请日：1997-09-02
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RAMESH NALLEPILLI S
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公开(公告)号：DE69717394D1
公开(公告)日：2003-01-09
申请号：DE69717394
申请日：1997-09-02
Applicant: LUCENT TECHNOLOGIES INC
Inventor： ALLPRESS STEPHEN ALAN , RAMESH NALLEPILLI S
Abstract: A plurality of modulated signals are generated for a data stream. Each modulated signal, which contains all of the information in the data stream, is generated at a different carrier frequency. The modulated signals are combined for transmission as a multi-band signal. In one embodiment, the modulated signals are compatible with signals generated in accordance with the IS-95 telecommunications standard. According to this embodiment, wideband data streams are combined with code sequences that are based on the same Walsh code sequences used to generate IS-95 signals. Each wideband data stream is encoded using either a particular Walsh code sequence or its logical negation to generate one coded stream for each carrier frequency used to generate the IS-95 signals. Each coded stream is then modulated at one of the carrier frequencies using spread-spectrum modulation to generate one of a plurality of modulated signals for that wideband data stream, where each modulated signals contains all of the information in the original wideband data stream. Through systematic assignment of Walsh code sequences and their logical negations, and through appropriate spread-spectrum modulation of the wideband data, the resulting multi-band modulated signal for each wideband data stream is assured of being orthogonal to all other such multi-band modulated signals, as well as orthogonal to every IS-95 signal. As such, the invention increases both the user and data-rate capacities of an IS-95 network without requiring any additional carrier frequencies or code sequences beyond those already supported by the IS-95 network.
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Patent Agency Ranking
公开(公告)号：ID27248A
公开(公告)日：2001-03-15
申请号：ID20000790
申请日：2000-09-13
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LI QUINN , ALLPRESS STEPHEN ALAN , BUEHRER R MICHAEL , RAMESH NALLEPILLI S , SONI ROBERT ATMARAM
Abstract: Disclosed is a common transmitter architecture having incorporated both open loop transmit diversity schemes using a plurality of binary switches. Employment of binary switches allows for the sharing of certain components whether the transmitter is utilizing a orthogonal transmit diversity (OTD) scheme or a space time spreading (STS) scheme. Accordingly, the number of components in the transmitter is minimized and the complexity of the transmitter is simple enough to be implemented into a single application specific integrated chip.
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公开(公告)号：AU5653200A
公开(公告)日：2001-03-15
申请号：AU5653200
申请日：2000-09-06
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LI QUINN , ALLPRESS STEPHEN ALAN , BUEHRER R MICHAEL , RAMESH NALLEPILLI S , SONI ROBERT ATMARAM
Abstract: Disclosed is a common transmitter architecture having incorporated both open loop transmit diversity schemes using a plurality of binary switches. Employment of binary switches allows for the sharing of certain components whether the transmitter is utilizing a orthogonal transmit diversity (OTD) scheme or a space time spreading (STS) scheme. Accordingly, the number of components in the transmitter is minimized and the complexity of the transmitter is simple enough to be implemented into a single application specific integrated chip.
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公开(公告)号：CA2212265C
公开(公告)日：2000-10-31
申请号：CA2212265
申请日：1997-07-31
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RAMESH NALLEPILLI S , ALLPRESS STEPHEN ALAN
Abstract: A plurality of modulated signals are generated for a data stream. Each modulated signal, which contains all of the information in the data stream, is generated at a different carrier frequency. The modulated signals are combined for transmission as a multi-band signal. In one embodiment, the modulated signals are compatible with signals generated in accordance with the IS-95 telecommunications standard. According to this embodiment, wideband data streams are combined with code sequences that are based on the same Walsh code sequences used to generate IS-95 signals. Each wideband data stream is encoded using either a particular Walsh code sequence or its logical negation to generate one coded stream for each carrier frequency used to generate the IS-95 signals. Each coded stream is then modulated at one of the carrier frequencies using spread-spectrum modulation to generate one of a plurality of modulated signals for that wideband data stream, where each modulated signals contains all of the information in the original wideband data stream. Through systematic assignment of Walsh code sequences and their logical negations, and through appropriate spread-spectrum modulation of the wideband data, the resulting multi-band modulated signal for each wideband data stream is assured of being orthogonal to all other such multi-band modulated signals, as well as orthogonal to every IS-95 signal. As such, the invention increases both the user and data-rate capacities of an IS-95 network without requiring any additional carrier frequencies or code sequences beyond those already supported by the IS-95 network.
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公开(公告)号：DE69717394T2
公开(公告)日：2003-08-21
申请号：DE69717394
申请日：1997-09-02
Applicant: LUCENT TECHNOLOGIES INC
Inventor： ALLPRESS STEPHEN ALAN , RAMESH NALLEPILLI S
Abstract: A plurality of modulated signals are generated for a data stream. Each modulated signal, which contains all of the information in the data stream, is generated at a different carrier frequency. The modulated signals are combined for transmission as a multi-band signal. In one embodiment, the modulated signals are compatible with signals generated in accordance with the IS-95 telecommunications standard. According to this embodiment, wideband data streams are combined with code sequences that are based on the same Walsh code sequences used to generate IS-95 signals. Each wideband data stream is encoded using either a particular Walsh code sequence or its logical negation to generate one coded stream for each carrier frequency used to generate the IS-95 signals. Each coded stream is then modulated at one of the carrier frequencies using spread-spectrum modulation to generate one of a plurality of modulated signals for that wideband data stream, where each modulated signals contains all of the information in the original wideband data stream. Through systematic assignment of Walsh code sequences and their logical negations, and through appropriate spread-spectrum modulation of the wideband data, the resulting multi-band modulated signal for each wideband data stream is assured of being orthogonal to all other such multi-band modulated signals, as well as orthogonal to every IS-95 signal. As such, the invention increases both the user and data-rate capacities of an IS-95 network without requiring any additional carrier frequencies or code sequences beyond those already supported by the IS-95 network.
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公开(公告)号：CA2256822C
公开(公告)日：2003-01-14
申请号：CA2256822
申请日：1998-12-21
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RAMESH NALLEPILLI S
IPC: H04B1/69 , H04B1/707 , H04B7/02 , H04B7/06 , H04B7/12 , H04J11/00 , H04J13/00 , H04L5/02 , H04L5/12
Abstract: A wideband CDMA transmission system is disclosed that incorporates transmit diversity in both frequency and space. Some embodiments of the present invention are capable of transmitting a wideband signal with a high data rate to an appropriately- designed wideband CDMA wireless terminal and are also capable of transmitting a narrowband (e.g., IS-95 compliant) signal to a CDMA wireless terminal in the prior art. Some embodiments of the present invention are capable of co-existing in the same frequency spectrum that is allocated to existing narrowband wireless systems. And in some embodiments of the present invention the coded symbols from the interleaver are distributed among multiple earners th at are then radiated by spatially separated antennas. An illustrative embodiment of the present invention comprises: receiving a datastream of symbols that is to be transmitted to one wireless terminal; distributing at least some of the datastream of symbols to a first derivative datastream of symbols; distributing at least some of the datastream of symbols to a second derivative datastream of symbols; modulating the first derivative datastream of symbols onto a first carrier frequency to create a first modulated carrier; modulating the second derivative datastream of symbols onto a second carrier frequency that is different that the first carrier frequency to create a second modulated carrier; radiating the first modulated earner from a first antenna; and radiating the second modulated carrier from a second antenna that is separated from the first antenna.
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