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21.发明专利
公开(公告)号：CA2317621A1
公开(公告)日：2001-03-13
申请号：CA2317621
申请日：2000-09-06
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LI QUINN , ALLPRESS STEPHEN ALAN , BUEHRER R MICHAEL , SONI ROBERT ATMARAM , RAMESH NALLEPILLI S
Abstract: Disclosed is a common transmitter architecture having incorporated both op en loop transmit diversity schemes using a plurality of binary switches. Employment of binary switches allows for the sharing of certain components whether the transmitte r 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 th e 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：CA2212265A1
公开(公告)日：1998-03-13
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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23.发明专利
公开(公告)号：CA2317621C
公开(公告)日：2004-03-23
申请号：CA2317621
申请日：2000-09-06
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LI QUINN , ALLPRESS STEPHEN ALAN , RAMESH NALLEPILLI S , BUEHRER R MICHAEL , SONI ROBERT ATMARAM
Abstract: Disclosed is a common transmitter architecture having incorporated both op en loop transmit diversity schemes using a plurality of binary switches. Employment of binary switches allows for the sharing of certain components whether the transmitte r 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 th e 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：CA2284330C
公开(公告)日：2003-03-18
申请号：CA2284330
申请日：1999-09-29
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RAMESH NALLEPILLI S , LI QUINN
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 wit h 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 ca n 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 t he 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 betwe en 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 scrambli ng code sequence can be used for spreading, scrambling, de-spreading or de-scramblin g an information signal.
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公开(公告)号：DE69901870T2
公开(公告)日：2003-01-09
申请号：DE69901870
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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Patent Agency Ranking
公开(公告)号：CA2266165C
公开(公告)日：2002-09-24
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 th e 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 sign al 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 seco nd antenna for transmitting the second signal.
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公开(公告)号：BR0003460A
公开(公告)日：2001-04-03
申请号：BR0003460
申请日：2000-08-09
Applicant: LUCENT TECHNOLOGIES INC
Inventor： LI QUINN , RAMESH NALLEPILLI S
IPC: H04B1/707 , H04B7/02 , H04B7/06 , H04B7/12 , H04J11/00 , H04J13/18 , H04L1/00 , H04L1/04 , H04L1/06 , H04Q7/38
Abstract: A transmitter for wireless communications provides multiple types of orthogonality to improve transmit diversity. Transmit diversity is improved by using both coding and carrier frequency orthogonality. Data to be transmitted is broken into four parallel channels. Two of the channels are transmitted on a first carrier signal and the other two channels are transmitted on a second carrier signal. Channels transmitted on the same carrier signal are provided with orthogonal codes so that they may be separated by a receiver. Channels transmitted on different carrier signals may be encoded with identical orthogonal codes. The modulated carrier signals are then transmitted using at least two antennas, where one antenna is used for each carrier.
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公开(公告)号：CA2284330A1
公开(公告)日：2000-05-12
申请号：CA2284330
申请日：1999-09-29
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RAMESH NALLEPILLI S , LI QUINN
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：CA2282979A1
公开(公告)日：2000-05-12
申请号：CA2282979
申请日：1999-09-22
Applicant: LUCENT TECHNOLOGIES INC
Inventor： WU XIAO CHENG , WANG JIAN-REN , RAMESH NALLEPILLI S , MEYERS MARTIN HOWARD
IPC: H04Q7/38
Abstract: Disclosed is a method for significantly reducing the amount of collisions of access messages on reverse link Random Access Channels (RACH) by multiple mobilestations attempting to gain system access concurrently, thereby greatly improving access performance in wireless communications system using existing multiple access schemes. The improvement is achieved by transmitting a probe message instead of an access message over the RACH, wherein the probe message is shorter in length than the access message. Transmission of the probe messages utilizes less of the RACH than the longer access messages, thereby reducing the chance of collisions with other probe messages. The access message is subsequently sent on a traffic channel or a control channel designated by a base station receiving the probe message. Alternately, a data burst is transmitted over the designated traffic channel or control channel.
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公开(公告)号：CA2256822A1
公开(公告)日：1999-07-13
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 appropriatelydesigned 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 that 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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