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公开(公告)号:AU782983B2
公开(公告)日:2005-09-15
申请号:AU1827901
申请日:2001-02-02
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , LI JUNYI , RANGAN SUNDEEP , VENKATA SATHYADEV
Abstract: Timing and access signals, to be transmitted in designated timing and access intervals, are constructed from orthogonal multitone signals. The multitone signals may be similar to multitone signals used in OFDM data transmission, except that a cyclic prefix, which is associated with reception of the signals in a base station, is extended to cover the timing errors of mobile stations not yet synchronized. Design techniques which optimize the time resolvability and peak-to-average ratio of the multitone signals, an efficient fast Fourier transform (FFT) based technique for maximum likelihood timing estimation, and a robust linear filtering technique for averaging timing estimates from different synchronizations, are also provided.
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公开(公告)号:DE60111706D1
公开(公告)日:2005-08-04
申请号:DE60111706
申请日:2001-10-23
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , JUNYI LI , UPPALA SATHYADEV VENKATA
Abstract: In a wireless communications system, multicast messages are transported to groups of wireless terminals by employing a common control channel to transmit a multicast paging message indicating that multicast traffic data is to be transmitted to a particular group of wireless terminals. In an embodiment of the invention, the essential information transmitted in the common control channel is the identifier of the group of wireless terminals intended to receive the multicast traffic data and the location of a traffic channel on which the multicast traffic is to be transported in a channel resource which may include a representation of bandwidth and time interval. In accordance with an aspect of the invention, the common control channel is associated with a traffic channel in a prescribed fixed manner. Further, the traffic channel used for the purpose of multicast can be the same traffic channel used for the normal point-to-point transmission of traffic data.
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公开(公告)号:DE60101022D1
公开(公告)日:2003-11-27
申请号:DE60101022
申请日:2001-06-11
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , JUNYL LI , UPPALA SANTHYADEV VENKATA
Abstract: Access request transmissions are effected in a wireless communications system by assigning each mobile unit a unique dedicated uplink resource. Specifically, each mobile unit is assigned channel segments with distinct time slot indices and/or waveform indices, where waveforms with distinct indices are orthogonal. A base station can identify the mobile that has made an access request from the dedicated uplink resource. Therefore, no mobile identification number is needed in the uplink request message. Then, the base station can transmit a request response message on a shared downlink resource that may include the identification number of the requesting mobile unit to acknowledge reception of the request. The mobile unit may transmit on a shared uplink resource an acknowledgment of reception of the downlink request response message.
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公开(公告)号:DE60100534D1
公开(公告)日:2003-09-04
申请号:DE60100534
申请日:2001-08-20
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , LI JUNYI , UPPALA SATHYADEV VENKATA
Abstract: Latency in receiving and detecting paging messages at a wireless terminal is reduced by employing a unique "super" paging time slot format. A paging super time slot includes a plurality of prescribed time slots. Each wireless terminal is associated with cyclically recurring super time slots. A super slot is associated with one or more wireless terminals. A base station always selects the first available time slot in a super time slot to transmit a paging message to a wireless terminal that is associated with the super time slot. Each wireless terminal monitors every time slot in the associated super time slot until either detecting reception of its associated paging message or detecting an empty time slot. In another embodiment of the invention, a unique partially overlapping super time slot format is employed in which a super time slot has at least one time slot common to its adjacent super time slots. This allows wireless terminals associated with adjacent super time slots to share the common at least one time slot. In turn, this results in balanced traffic loads, smoothed traffic fluctuation and reduced congestion.
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公开(公告)号:CA2366343A1
公开(公告)日:2002-07-08
申请号:CA2366343
申请日:2001-12-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LI JUNYI , LAROIA RAJIV , UPPALA SATHYADEV VENKATA
Abstract: In a unique paging time slot format, each of the allocated paging time slo ts occurs periodically and is split into several prescribed paging time slots including at least one first type paging time slot having a relatively short duration and at least one second type paging time slot having a longer duration. The at leas t one first type paging time slots is of relatively short duration and transports an indication whether a particular associated wireless terminal was paged. The second type paging time slot is of longer duration than the first type time slot and transports the entire paging message. Specifically, a wireless terminal that is normally in a standby mode only has to enter a monitor mode, i.e., "wake up" , to monitor the relatively short first type paging time slot to determine whethe r it has been paged. If it has been paged, the wireless terminal then monitors the longer second type paging time slot to determine if it is transporting a valid pagi ng message for the paged wireless terminal. If no valid paged indication is detected in the first type paging time slot or no valid paging message is detected in the second type paging time slot, the wireless terminal returns to the standby mode, i.e., returns to a "sleep" state, and waits for the next periodic occurrence of its assigned paging time slot.
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公开(公告)号:AU8550301A
公开(公告)日:2002-05-09
申请号:AU8550301
申请日:2001-10-29
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , UPPALA SATHYADEV VENKATA , LI JUNYI
Abstract: In a wireless communications system, multicast messages are transported to groups of wireless terminals by employing a common control channel to transmit a multicast paging message indicating that multicast traffic data is to be transmitted to a particular group of wireless terminals. In an embodiment of the invention, the essential information transmitted in the common control channel is the identifier of the group of wireless terminals intended to receive the multicast traffic data and the location of a traffic channel on which the multicast traffic is to be transported in a channel resource which may include a representation of bandwidth and time interval. In accordance with an aspect of the invention, the common control channel is associated with a traffic channel in a prescribed fixed manner. Further, the traffic channel used for the purpose of multicast can be the same traffic channel used for the normal point-to-point transmission of traffic data.
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公开(公告)号:BR0102383A
公开(公告)日:2002-04-23
申请号:BR0102383
申请日:2001-06-13
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , UPPALA SATHYADEV VENKATA , LI JUNYI
Abstract: In a wireless communication system, mobile unit and base station access request and page transmissions are addressed by employing an efficient unified approach for the transmission and detection of both access requests from a mobile unit and pages from a base station. To this end, a mobile unit monitors for access requests and monitors a prescribed resource to detect if a page has been received. Upon detection of an access request, a corresponding request message is generated and transmitting substantially immediately to a base station, thereby minimizing latency in the access process. Concurrently, a base station monitors to determine if a page indication has been received and monitors a prescribed resource to determine if an access request message has been received. In this process, the processing of request messages takes precedence over the processing of pages. Upon detecting a received request message a request response message is generated and transmitted substantially immediately to the mobile unit, thereby also minimizing latency in the access process.
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公开(公告)号:CA2344844A1
公开(公告)日:2001-12-19
申请号:CA2344844
申请日:2001-04-23
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , LI JUNYI , UPPALA SATHYADEV VENKATA
Abstract: In a wireless communication system, mobile unit and base station access request and page transmissions are addressed by employing an efficient unified approach for the transmission and detection of both access requests from a mobile unit and pages from a base station. To this end, a mobile unit monitors for access requests and monitors a prescribed resource to detect if a page has been received. Upon detection of an access request, a corresponding request message is generated and transmitting substantially immediately to a base station, thereby minimizing latency in the access process. Concurrently, a base station monitors to determine if a page indication has been received and monitors a prescribed resource to determine if an access reques t message has been received. In this process, the processing of request messages takes precedence over the processing of pages. Upon detecting a received request message a request response message is generated and transmitted substantially immediately to t he mobile unit, thereby also minimizing latency in the access process.
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公开(公告)号:DE69900421D1
公开(公告)日:2001-12-13
申请号:DE69900421
申请日:1999-03-02
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , URBANKE RUDIGER L , RICHARDSON THOMAS J
Abstract: We describe an improved method for decreasing the probability of an unacceptably high peak-to-average power ratio in a signal to be transmitted by a Frequency Division Multiplexing (FDM) system, such as a discrete multitone (DMT) system. The method involves generating at least two alternative signal sequences, computing Fourier transforms of the respective alternative signal sequences, and selecting for transmission one of these sequences, based on the Fourier transform computations. More specifically, the selection of one sequence may be based, e.g., on the determination that the Fourier transform of that sequence has an acceptable peak power. Alternatively, a comparison may be made among the Fourier transforms of the respective signal sequences, and selection made of that sequence whose Fourier transform exhibits the lowest peak power.
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公开(公告)号:CA2338471A1
公开(公告)日:2001-10-18
申请号:CA2338471
申请日:2001-02-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor: VISWANATH PRAMOD , RANGAN SUNDEEP , LI JUNYI , LAROIA RAJIV
IPC: H04B1/713 , H04B1/7143 , H04B1/7156 , H04B7/26 , H04J11/00 , H04L5/02 , H04L27/26 , H04Q7/36 , H04B1/76
Abstract: A base station having the strongest downlink signal is identified by utilizi ng a unique slope of a pilot tone hopping sequence being transmitted by a base station. Specifically, base station identification is realized by determining the slo pe of the strongest received pilot signal, i.e., the received pilot signal having the maximum energy. In an embodiment of the invention, the pilot tone hopping sequence i s based on a Latin Squares sequence. With a Latin Squares based pilot tone hopping sequence, all a mobile user unit needs is to locate the frequency of the pilot tones at on e time because the pilot tone locations at subsequent times can be determined from the slop e of the Latin Squares pilot tone hopping sequence. The slope and initial frequency shift of the pilot tone hopping sequence with the strongest received power is determined by employing a unique maximum energy detector. In one embodiment, the slope and initial frequency shift of the pilot signal having the strongest received power is determined by finding the slope and initial frequency shift of a predicted s et of pilot tone locations having the maximum received energy. In another embodiment, th e frequency shift of the pilot signal with the strongest, i.e., maximum, received power is estimated at each of times "t". These frequency shifts are employed in accordance with a prescribed relationship to determine the unknown slope and the initial frequency shift of the pilot signal.
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