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公开(公告)号：CA2314032C
公开(公告)日：2004-04-13
申请号：CA2314032
申请日：2000-07-13
Applicant: LUCENT TECHNOLOGIES INC
Inventor： NARAYANASWAMY SHANKAR , KRISHNAMOORTHY RAJEEV , VISWANATHAN HARISH , RUPP MARKUS
Abstract: In a system in which the modulation scheme employed may change on a per-time - slot basis, a user's available data rate may change even if the user maintains th e same number of time slots, because the capacity of the user's time slots may change. If one or more such changes in modulation scheme occurs, the data rate available to th e user may no longer match his current data rate needs. Therefore, a method is disclose d for determining the number of time slots to assign to a user as a function of th e user's current data rate requirement and the actual current cumulative data rate of the tim e slots currently assigned to the user. The user data rate requirement may further b e a function of a quality of service (QoS) contracted for by the user. Thus, the assignment of the time slots within the frame is made dynamically and the number of time slots employed by a user is increased or decreased according to the user's current data rate requirements and the ability of the time slots already assigned to the user to meet those requirements.
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公开(公告)号：BR0103579A
公开(公告)日：2002-07-30
申请号：BR0103579
申请日：2001-08-22
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RUPP MARKUS
Abstract: Use of a training sequence having terms that are orthogonal to each other are employed to considerably speed up execution of the LMS algorithm. Such orthogonal sequences are developed for a channel that is described as a finite impulse response (FIR) filter having a length Mnew from the already existing orthogonal training sequences for at least two channels that have respective lengths Mold1 and Mold2 each that is less than Mnew such that the product of Mold1 and Mold2 is equal to Mnew when Mold1 and Mold2 have no common prime number factor. More specifically, a set of initial existing orthogonal training sequences is found, e.g., using those that were known in the prior art or by performing a computer search over known symbol constellations given a channel of length M. Thereafter, an orthogonal training sequence of length Mnew is developed, where the product of Mold1 and Mold2 is equal to Mnew by repeating the training sequence old1 Mold2 number of times to form a first concatenated sequence and repeating the training sequence old2 Mold1 number of times to form a second concatenated sequence, so that both the first concatenated sequence and the second concatenated sequence have the same length. Each term of the first concatenated sequence is multiplied by the correspondingly located term in the second concatenated sequence which is placed in the same location in a new sequence made up of the resulting Mnew products. This new sequence is an orthogonal sequence of length Mnew.
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公开(公告)号：CA2352010A1
公开(公告)日：2002-02-28
申请号：CA2352010
申请日：2001-07-03
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RUPP MARKUS
IPC: H04L27/18 , H04B1/10 , H04B3/06 , H04B7/04 , H04B7/06 , H04B7/08 , H04J11/00 , H04J13/10 , H04L7/00 , H04B1/18 , H04B7/204
Abstract: Orthogonal sequences can be developed and used for use training and synchronizing in CDMA and TDMA systems. In particular, once a sequence is developed that has the length of the product of the channel length and the number of transmit antennas, the sequence is offset by a different amount for each transmit antenna. For example, each sequence could be offset by a multiple of the channel leng th for each transmit antenna, where the multiple ranges from 0 to N-1, where N is the number of transmit antennas. Furthermore, by not using exactly the same amount of offs et shifting for each transmit antenna, e.g., not having each signal offset by the channe l length, but keeping the overall total shifting the same, e.g., the average of each shift is the channel length, it is possible to determine at a receiver from which transmit antenn a a particular signal originated.
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公开(公告)号：CA2351100A1
公开(公告)日：2002-02-28
申请号：CA2351100
申请日：2001-06-20
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RUPP MARKUS
IPC: H04L27/01 , H04B1/10 , H04B1/69 , H04B3/10 , H04J13/00 , H04J13/10 , H04J13/12 , H04L25/03 , G06F17/10
Abstract: Use of a training sequence having terms that are orthogonal to each other a re employed to considerably speed up execution of the LMS algorithm. Such orthogonal sequences are developed for a channel that is described as a finite impulse response (FIR) filter having a length M new from the already existing orthogonal training sequences for at least two channels that have respective lengths M old1 and M old2 each that is less than M new such that the product of M old1 and M old2 is equal to M new when M old1 and M old2 have no common prime number factor. More specifically, a set of initial existing orthogonal training sequences is found, e.g., using those that were known in the prior art or by performing a computer search over known symbol constellations given a channe l of length M. Thereafter, an orthogonal training sequence of length M new is developed, where the product of M old1 and M old2 is equal to M new by repeating the training sequence old 1 M old2 number of times to form a first concatenated sequence and repeating t he training sequence old2 M old1 number of times to form a second concatenated sequence, so that both the first concatenated sequence and the second concatenated sequence ha ve the same length. Each term of the first concatenated sequence is multiplied by the correspondinglylocated term in the second concatenated sequence which is pla ced in the same location in a new sequence made up of the resulting M new products. This new sequence is an orthogonal sequence of length M new.
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公开(公告)号：BR0003016A
公开(公告)日：2001-03-13
申请号：BR0003016
申请日：2000-07-20
Applicant: LUCENT TECHNOLOGIES INC
Inventor： KRISHNAMOORTHY RAJEEV , VISWANATHAN HARISH , NARAYANASWAMY SHANKAR , RUPP MARKUS
Abstract: A two layered segmentation technique coupled with a two layer error detection technique is used to implement the wired to wireless network interface. A wireless network divides network layer packets from a wired network into radio data link packets, and the information within the radio data link packets is divided into portions that can be placed into time slots. Error detection is performed on each of the time slots and also at the radio data link packet level to determine if there is an error within the radio data link packet. Errors detected in any radio data link packet only requires retransmission of the radio data link packet in which the error was detected, and, advantageously, do not require retransmission of the entire network layer packet as would have been required in a system that mapped directly from network layer packets to time slots.
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Patent Agency Ranking
公开(公告)号：CA2313978A1
公开(公告)日：2001-01-27
申请号：CA2313978
申请日：2000-07-13
Applicant: LUCENT TECHNOLOGIES INC
Inventor： KRISHNAMOORTHY RAJEEV , NARAYANASWAMY SHANKAR , VISWANATHAN HARISH , RUPP MARKUS
Abstract: A two layered segmentation technique coupled with a two layer error detecti on technique is used to implement the wired to wireless network interface. A wireless network divides network layer packets from a wired network into radio data link packets, and the information within the radio data link packets is divided into portions that can be placed into time slots. Error detection is performed on each of the time slo ts and also at the radio data link packet level to determine if there is an error within th e radio data link packet. Errors detected in any radio data link packet only requires retransmission of the radio data link packet in which the error was detected, and, advantageously, do not require retransmission of the entire network layer packet as would have been required in a system that mapped directly from network layer packets to time slots. Furthe r advantageously, the system is able to be employed by systems that utilize dynamic constellation mapping schemes which result in different time slots for the same user being mapped with different constellations, and so they have different bit t o symbol ratios. This is because such changes in the constellation mapping scheme are handled at the time slot level, and are not seen at the radio data link packet level. T he segmentation of the network layer packets into radio link packets is independent of the number and size of the time slots which will carry the radio link packets.
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公开(公告)号：ID26063A
公开(公告)日：2000-11-23
申请号：ID20000316
申请日：2000-04-20
Applicant: LUCENT TECHNOLOGIES INC
Inventor： KHRISHNAMOORTHY RAJEEV , RUPP MARKUS , VISWANATHAN HARISH
Abstract: In a TDMA system a multifunction control channel is employed that carries data used for implementing channel access functionality for users and is also employed at the remote terminals in the performance of modem functionality. In other words, information necessary to accurately receive data on the user traffic channels is obtainable by processing the multifunction control channel. This is achieved by arranging the broadband channel of the TDMA system as a repeating frame having time slots in which at least one time slot is reserved for use as the multifunction control channel, and the data that is transmitted on the multifunction control channel is encoded using a spread spectrum format. To this end the data carried on the multifunction control channel is encoded in a way that uses each symbol of the multifunction control channel as if it were a so-called spread spectrum "chip". At least one of the remaining time slots of the frame, and preferably all of the remaining time slots, which are typically used to carry user traffic arranged as logical channels, are not spread spectrum encoded. With regard to modem functionality, the remote terminals use the received multifunction control channel to a) perform frame synchronization, i.e., frame timing, b) perform frequency offset estimation, c) obtain an estimate of the channel impulse response, and d) estimate the received signal strength for use in gain control.
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公开(公告)号：AU3401200A
公开(公告)日：2000-11-23
申请号：AU3401200
申请日：2000-05-10
Applicant: LUCENT TECHNOLOGIES INC
Inventor： KRISHNAMOORTHY RAJEEV , RUPP MARKUS , VISWANATHAN HARISH
IPC: H04B1/7075 , H04B7/26 , H04J3/00 , H04W28/26 , H04W74/02 , H04W74/04 , H04W99/00 , H04L7/04 , H04L5/22 , H04J13/00 , H04B7/212 , H04B7/216
Abstract: In a TDMA system a multifunction control channel is employed that carries data used for implementing channel access functionality for users and is also employed at the remote terminals in the performance of modem functionality. In other words, information necessary to accurately receive data on the user traffic channels is obtainable by processing the multifunction control channel. This is achieved by arranging the broadband channel of the TDMA system as a repeating frame having time slots in which at least one time slot is reserved for use as the multifunction control channel, and the data that is transmitted on the multifunction control channel is encoded using a spread spectrum format. To this end the data carried on the multifunction control channel is encoded in a way that uses each symbol of the multifunction control channel as if it were a so-called spread spectrum "chip". At least one of the remaining time slots of the frame, and preferably all of the remaining time slots, which are typically used to carry user traffic arranged as logical channels, are not spread spectrum encoded. With regard to modem functionality, the remote terminals use the received multifunction control channel to a) perform frame synchronization, i.e., frame timing, b) perform frequency offset estimation, c) obtain an estimate of the channel impulse response, and d) estimate the received signal strength for use in gain control.
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公开(公告)号：CA2351100C
公开(公告)日：2009-09-15
申请号：CA2351100
申请日：2001-06-20
Applicant: LUCENT TECHNOLOGIES INC
Inventor： RUPP MARKUS
IPC: H04B1/10 , H04L27/01 , G06F17/10 , H04B1/69 , H04B3/10 , H04J13/00 , H04J13/10 , H04J13/12 , H04L25/03
Abstract: Use of a training sequence having terms that are orthogonal to each other ar e employed to considerably speed up execution of the LMS algorithm. Such orthogonal sequences are developed for a channel that is described as a finite impulse response (FIR) filter having a length M new from the already existing orthogonal training sequences for at least two channels that have respective lengths M old1 and M old2 each that is less than M new such that the product of M old1 and M old2 is equal to M new when M old1 and M old2 have no common prime number factor. More specifically, a set of initial existing orthogonal training sequences is found, e.g., using those that were known in the prior art or by performing a computer search over known symbol constellations given a channe l of length M. Thereafter, an orthogonal training sequence of length M new is developed, where the product of M old1 and M old2 is equal to M new by repeating the training sequence old1 M old2 number of times to form a first concatenated sequence and repeating t he training sequence old2 M old1 number of times to form a second concatenated sequence, so that both the first concatenated sequence and the second concatenated sequence ha ve the same length. Each term of the first concatenated sequence is multiplied by the correspondingly located term in the second concatenated sequence which is placed in the same location in a new sequence made up of the resulting M new products. This new sequence is an orthogonal sequence of length M new.
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公开(公告)号：DE60037161T2
公开(公告)日：2008-10-02
申请号：DE60037161
申请日：2000-05-09
Applicant: LUCENT TECHNOLOGIES INC
Inventor： KRISHNAMOORTHY RAJEEV , RUPP MARKUS , VISWANATHAN HARISH
Abstract: In a TDMA system a multifunction control channel is employed that carries data used for implementing channel access functionality for users and is also employed at the remote terminals in the performance of modem functionality. In other words, information necessary to accurately receive data on the user traffic channels is obtainable by processing the multifunction control channel. This is achieved by arranging the broadband channel of the TDMA system as a repeating frame having time slots in which at least one time slot is reserved for use as the multifunction control channel, and the data that is transmitted on the multifunction control channel is encoded using a spread spectrum format. To this end the data carried on the multifunction control channel is encoded in a way that uses each symbol of the multifunction control channel as if it were a so-called spread spectrum "chip". At least one of the remaining time slots of the frame, and preferably all of the remaining time slots, which are typically used to carry user traffic arranged as logical channels, are not spread spectrum encoded. With regard to modem functionality, the remote terminals use the received multifunction control channel to a) perform frame synchronization, i.e., frame timing, b) perform frequency offset estimation, c) obtain an estimate of the channel impulse response, and d) estimate the received signal strength for use in gain control.
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