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公开(公告)号:BR0104819A
公开(公告)日:2002-07-02
申请号:BR0104819
申请日:2001-10-25
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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42.
公开(公告)号:CA2351971A1
公开(公告)日:2002-02-16
申请号:CA2351971
申请日:2001-06-29
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LI JUNYI , UPPALA SATHYADEV VENKATA , LAROIA RAJIV
Abstract: Uplink traffic channel allocation is realized by utilizing a dedicated contr ol channel in which a prescribed portion of the control channel resource, for example, frequency, time slot or the like, is reserved for transporting the uplink traffic channel requests. Both the base station and the particular mobile unit know the prescribed portion of the control channel resource a priori. Consequently, when the particular mobile unit transmits an uplink traffic channel request via the prescribed portion of the control channel resource there is no need for adding any control header information, thereby minimizing overhead. Furthermore, the length of the uplink traffic channel requests can be optimally chosen without constraints imposed by other contro l message schemes. Reduced overhead coupled with the prescribed portion of the control channel resource arriving quite frequently reduces latency in the particular mobile unit acquiring an uplink traffic channel. In one example, delivery of adequate uplink traffic channel request information to the base station, while minimizing the adverse impact of losing requests, is ensured by persistently transmitting t he requests. Specifically, after the mobile unit transmits a first request, it transmits a second or even a third request instead of waiting to receive a response message from t he base station and/or waiting for a timer to time out. By the mobile unit using suc h a persistent request transmission scheme, the base station can readily determi ne the true value of the received request by eliminating the transmission loop delay effect, thereby allowing a sensible assignment decision to be made.
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公开(公告)号:CA2344839A1
公开(公告)日:2001-12-19
申请号:CA2344839
申请日:2001-04-23
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , UPPALA SATHYADEV VENKATA , LI JUNYI
Abstract: Access request transmissions are effected in a wireless communications syst em 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 ba se 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 reques t response message.
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公开(公告)号:BRPI0100361B1
公开(公告)日:2015-12-15
申请号:BR0100361
申请日:2001-02-05
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LI JUNYI , LAROIA RAJIV , UPPALA SATHYADEV VENKATA , RANGAN SUNDEEP
Abstract: método e aparelho de comunicação de link ascendente entre uma estação móvel e uma estação base de um sistema de comunicação sem fio técnicas aperfeiçoadas de sincronização de temporização e de controle de acesso para uso em um sistema sem fio multiplexado de divisão de freqüência ortogonal (ofdm) ou outro tipo de sistema de comunicação sem fio. de acordo com a invenção, um sistema de controle de acesso e de sincronização de link ascendente é provido no qual as estações móveis transmitem certos sinais de temporização e de acesso em intervalos dedicados em uma seqüência de link ascendente. controle de acesso é implementado ilustrativamente como um processo de dois estágios no qual uma estação móvel determinada transmite primeiro um sinal genérico de acesso de link ascendente em um dos intervalos. se esse acesso for aceito, a estação base transmite uma confirmação de acesso contendo correções iniciais de energia e de temporização, junto com atribuições iniciais de canal no qual a estação móvel pode iniciar um processo de estabelecimento de chamada. para re-sincronização, estações móveis transmitem sinais de sincronização de temporização nos intervalos dedicados de temporização e de acesso. a estação base mede o tempo de chegada dos sinais, e envia de volta correções apropriadas de temporização. a invenção dessa forma garante que seja mantida a ortogonalidade entre as estações móveis.
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公开(公告)号:CA2330776C
公开(公告)日:2008-03-18
申请号:CA2330776
申请日:2001-01-12
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LI JUNYI , RANGAN SUNDEEP , LAROIA RAJIV , UPPALA SATHYADEV VENKATA
Abstract: Signal construction, detection and estimation techniques for use in uplink timing synchronization and access control in an orthogonal frequency division multiplexed (OFDM) wireless system or other type of wireless communication system. In accordanc e with an illustrative embodiment of the invention, 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 associated with reception of the signals in a ba se station is extended to cover the timing errors of mobile stations not yet synchronized. The invention also provides design techniques which optimize the time resolvability and pe ak- 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 techniqu e for averaging timing estimates from different synchronizations.
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公开(公告)号:CA2327980C
公开(公告)日:2007-02-13
申请号:CA2327980
申请日:2000-12-08
Applicant: LUCENT TECHNOLOGIES INC
Inventor: RANGAN SUNDEEP , UPPALA SATHYADEV VENKATA , LI JUNYI , LAROIA RAJIV
IPC: H04J11/00 , H04B1/7136 , H04B1/7143 , H04L5/02
Abstract: Tone sequences in a frequency hopping arrangement are generated and assign ed by advantageously employing a combination of a sequence generator and a sequence assignor to generate sequences and assign them on a time slot by time slot basis. In a transmitter, the sequence generator and sequence assignor, in combination wi th a user tone assignor are employed to generate and assign tone sequences to a user o n a time slot by time slot basis. In a receiver, the sequence generator and sequence assignor, in combination with a user tone identifier are employed to generate sequences a nd to identify incoming tone sequences to a user on a time slot by time slot basis . Specifically, the sequence assignment in a time slot is such that a prescrib ed plurality of sequences is assigned to a particular user. This partitioning of the tasks facilitates the use of a sequence generator that generates sequences with the desirable properties of interference and frequency diversity and, which, leaves the task of properly assigning these sequences among one or more users to the sequence assignor. The sequen ce assignor functions in such a manner that the interference and frequency diversity properties for the one or more users are preserved, and this is further facilitated by assigning sequences in such a manner that they maximally overlap prior assigned sequences. In one embodiment of the invention, a Latin square based sequence is generated in accordance with a first prescribed process. In a second embodiment of the invention, a Latin cube based sequence is generated in accordance with a second prescribed process. In a third embodiment of the invention, a Latin hypercub e of prescribed dimension based sequence is generated in accordance with a third prescribed process. In still another embodiment of the invention, the principles of the invention are employed to realize frequency band hopping.
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公开(公告)号:AU783584B2
公开(公告)日:2005-11-10
申请号:AU8550301
申请日:2001-10-29
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , LI JUNYI , 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:CA2366253C
公开(公告)日:2005-10-18
申请号:CA2366253
申请日:2001-12-27
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LI JUNYI , LAROIA RAJIV , UPPALA SATHYADEV VENKATA
Abstract: An unique arrangement including a so-called timing control order and timing control signals is employed to identify whether wireless terminals ar e reachable within a base station cell coverage area in a wireless communications system. To this end, detection of a particular wireless terminal being alive and well, and within the cell coverage area associated with a base station is effected by the base station transmitting a timing control order in a timing control time slot reserved for the particular wireless terminal. If the particular wireless terminal receives the timing control order, it transmits a prescribed timing control message at a prescribed time. If the base station does not receive the timing contro l message, it is an indication that communication with the particular wireless terminal has been lost.
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公开(公告)号:DE60102920T2
公开(公告)日:2005-04-28
申请号:DE60102920
申请日:2001-08-20
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , LI JUNYI , UPPALA SATHYADEV VENKATA
Abstract: An unique arrangement including a so-called timing control order and timing control signals is employed to identify whether wireless terminals are reachable within a base station cell coverage area in a wireless communications system. To this end, detection of a particular wireless terminal being alive and well, and whitin the cell coverage area associated with a base station if effected by the base station transmitting a timing control order (601) in a timing control time slot reserved for the particular wireless terminal. If the particular wireless terminal receives the timing control order, it transmits a prescribed timing control message at a prescribed time. If the base station does not receive the timing control message, it is an indication that communication with the particular wireless terminal has been lost.
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50.
公开(公告)号:AU778564B2
公开(公告)日:2004-12-09
申请号:AU5794101
申请日:2001-08-09
Applicant: LUCENT TECHNOLOGIES INC
Inventor: LAROIA RAJIV , LI JUNYI , UPPALA SATHYADEV VENKATA
Abstract: Uplink traffic channel allocation is realized by utilizing a dedicated control channel in which a prescribed portion of the control channel resource, for example, frequency, time slot or the like, is reserved for transporting the uplink traffic channel requests. Both the base station and the particular mobile unit know the prescribed portion of the control channel resource a priori. Consequently, when the particular mobile unit transmits an uplink traffic channel request via the prescribed portion of the control channel resource there is no need for adding any control header information, thereby minimizing overhead. Furthermore, the length of the uplink traffic channel requests can be optimally chosen without constraints imposed by other control message schemes. Reduced overhead coupled with the prescribed portion of the control channel resource arriving quite frequently reduces latency in the particular mobile unit acquiring an uplink traffic channel. In one example, delivery of adequate uplink traffic channel request information to the base station, while minimizing the adverse impact of losing requests, is ensured by persistently transmitting the requests. Specifically, after the mobile unit transmits a first request, it transmits a second or even a third request instead of waiting to receive a response message from the base station and/or waiting for a timer to time out. By the mobile unit using such a persistent request transmission scheme, the base station can readily determine the true value of the received request by eliminating the transmission loop delay effect, thereby allowing a sensible assignment decision to be made.
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