Multi-carrier communications with adaptive cluster configuration and switching
원문보기
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
H04B-007/208
H04W-072/04
H04W-074/04
H04B-007/204
H04W-004/00
출원번호
US-0801788
(2013-03-13)
등록번호
US-8767702
(2014-07-01)
발명자
/ 주소
Li, Xiaodong
Liu, Hui
Zhang, Wenzhong
Li, Kemin
출원인 / 주소
Adaptix, Inc.
대리인 / 주소
Martin & Ferraro, LLP
인용정보
피인용 횟수 :
10인용 특허 :
328
초록▼
A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a
A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.
대표청구항▼
1. A method of allocating clusters, each of the clusters comprising a plurality of subcarriers, by a base station which communicates with a plurality of subscriber stations using multiple access technology in a cell, the method comprising: allocating to a first subscriber station a diversity cluster
1. A method of allocating clusters, each of the clusters comprising a plurality of subcarriers, by a base station which communicates with a plurality of subscriber stations using multiple access technology in a cell, the method comprising: allocating to a first subscriber station a diversity cluster to be used for a first data transmission to the first subscriber station by providing a first cluster identification, the allocated diversity cluster including a plurality of disjoint subcarriers; andallocating to a second subscriber station a coherence cluster to be used for a second data transmission to the second subscriber station by providing a second cluster identification, the second data transmission to occur during the same time period as the first data transmission to the first subscriber station using the allocated diversity cluster, the allocated coherence cluster including only consecutive subcarriers. 2. The method as claimed in claim 1, further comprising: receiving, from the first subscriber station, feedback information on channel performance of the clusters of the subcarriers used in the cell. 3. The method as claimed in claim 2, wherein the allocation of the diversity cluster is based on the feedback information received from the first subscriber station. 4. The method as claimed in claim 3, further comprising: receiving, from the second subscriber station, feedback information on channel performance of the clusters of the subcarriers used in the cell, the allocation of the coherence cluster being based on the feedback information received from the second subscriber station. 5. The method as claimed in claim 1, wherein the plurality of the disjoint subcarriers of the allocated diversity cluster are spread farther apart than a coherence bandwidth of a respective channel. 6. The method as claimed in claim 1, wherein the consecutive subcarriers of the allocated coherence cluster are within a coherence bandwidth of a respective channel. 7. The method as claimed in claim 1, further comprising: indicating a modulation and coding format to be used for the respective first and second data transmissions over the respective allocated diversity and coherence clusters. 8. The method as claimed in claim 1, further comprising: subsequently allocating to the first subscriber station a different cluster by providing a different cluster identification. 9. The method as claimed in claim 8, wherein the different allocated cluster is a different allocated diversity cluster or a different allocated coherence cluster. 10. The method as claimed in claim 9, wherein the different allocated diversity cluster has at least one subcarrier that is different from at least one subcarrier associated with the allocated diversity cluster. 11. The method as claimed in claim 1, wherein the allocated diversity cluster includes a first set of subcarriers of the plurality of the disjoint subcarriers at a first time slot and a second set of subcarriers of the plurality of the disjoint subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, the first set of the subcarriers of the plurality of the disjoint subcarriers being the same as the second set of the subcarriers of the plurality of the disjoint subcarriers. 12. The method as claimed in claim 1, wherein the allocated diversity cluster includes a first set of subcarriers of the plurality of the disjoint subcarriers at a first time slot and a second set of subcarriers of the plurality of the disjoint subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, the first set of the subcarriers of the plurality of the disjoint subcarriers being different than the second set of the subcarriers of the plurality of the disjoint subcarriers. 13. The method as claimed in claim 1, wherein the allocated diversity cluster includes a first subcarrier of the plurality of the disjoint subcarriers at a first time slot and not at a second time slot, a second subcarrier of the plurality of the disjoint subcarriers at the second time slot and not at the first time slot, the second time slot being immediately subsequent to the first time slot, the first subcarrier of the plurality of the disjoint subcarriers being different and disjoint from the second subcarrier of the plurality of the disjoint subcarriers. 14. The method as claimed in claim 1, further comprising: allocating an additional coherence cluster to the second subscriber station for use at the same time as the allocated coherence cluster; andproviding an additional coherence cluster identification to the second subscriber station, which specifies the additional allocated coherence cluster. 15. The method as claimed in claim 4, wherein the received feedback information from the first subscriber, prior to the allocation of the diversity cluster, is less than the received feedback information from the second subscriber, prior to the allocation of the coherence cluster. 16. The method as claimed in claim 1, wherein each of a plurality of subscriber stations of a first set are allocated one of a plurality of diversity clusters for use at the same time as each one of a plurality of coherence clusters that are allocated to each of a plurality of subscriber stations of a second set, the number of subscriber stations in the plurality of the subscriber stations of the first and second sets change at a later time, a corresponding ratio between the number of the allocated diversity clusters to the plurality of the subscriber stations of the first set and the number of the allocated coherence clusters to the plurality of the subscriber stations of the second set also change. 17. The method as claimed in claim 16, wherein the plurality of the subscriber stations of the first set and the plurality of the subscriber stations of the second set are decided based on at least one of a location and a mobility. 18. The method as claimed in claim 1, further comprising: receiving signal to interference noise information regarding at least one cluster from the first subscriber;analyzing a variation of the received signal to interference noise information regarding the at least one cluster from the first subscriber, the allocation to the first subscriber of the diversity cluster being based on the analyzed variation of the received signal to interference noise information from the first subscriber;receiving signal to interference noise information regarding at least one cluster from the second subscriber; andanalyzing a variation of the received signal to interference noise information regarding the at least one cluster from the second subscriber, the allocation to the second subscriber of the coherence cluster being based on the analyzed variation of the received signal to interference noise information from the second subscribe. 19. The method as claimed in claim 16, wherein the base station determines a location of the plurality of the subscriber stations of the first set based on a strength of signals received from the plurality of the subscriber stations of the first set. 20. The method as claimed in claim 18, wherein the analyzed variation of the received signal to interference noise information of the allocated diversity cluster is higher than the analyzed variation of the received signal to interference noise information of the allocated coherence cluster, the analysis of the variation of the received signal to interference noise information of the at least one cluster from the first subscriber and of the at least one cluster from the second subscriber occurring over a moving window of time. 21. A base station that communicates with a plurality of subscriber stations using multiple access technology in a cell and allocates clusters, each of the clusters comprising a plurality of subcarriers, the base station comprising: a controller configured to: allocate, to a first subscriber station, a diversity cluster to be used for a first data transmission to the first subscriber station by providing a first cluster identification, the diversity cluster allocated by the controller including a plurality of disjoint subcarriers; andallocate, to a second subscriber station, a coherence cluster to be used for a second data transmission to the second subscriber station by providing a second cluster identification, the second data transmission occurring during the same time period as the first data transmission to the first subscriber station using the allocated diversity cluster, the coherence cluster allocated by the controller including only consecutive subcarriers; andreceive/transmit circuitry configured to: provide the first and the second subscriber stations with the respective first and second cluster identifications for the respective allocated diversity and coherence clusters. 22. The base station as claimed in claim 21, wherein the receive/transmit circuitry is further configured to receive feedback information on channel performance of the clusters of the subcarriers used in the cell, the feedback information being used for the allocations of the diversity and the coherence clusters. 23. The base station as claimed in claim 21, wherein the plurality of the disjoint subcarriers of the allocated diversity cluster is spread farther apart than a channel coherence bandwidth. 24. The base station as claimed in claim 21, wherein the consecutive subcarriers of the allocated coherence cluster are within a coherence bandwidth of a respective channel. 25. The base station as claimed in claim 21, wherein the controller is further configured to indicate a modulation and coding format to be used for the respective first and second data transmissions over the respective allocated diversity and coherence clusters. 26. The base station as claimed in claim 21, wherein the controller is further configured to subsequently allocate to the first subscriber a different cluster by providing a different cluster identification. 27. The base station as claimed in claim 26, wherein the different cluster allocated by the base station is a different allocated diversity cluster or a different allocated coherence cluster. 28. The base station as claimed in claim 21, wherein the allocated diversity cluster includes a first set of subcarriers of the plurality of the disjoint subcarriers at a first time slot and a second set of subcarriers of the plurality of the disjoint subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, the first set of the subcarriers of the plurality of the disjoint subcarriers being the same as the second set of the subcarriers of the plurality of the disjoint subcarriers. 29. The base station as claimed in claim 21, wherein the allocated diversity cluster includes a first set of subcarriers of the plurality of the disjoint subcarriers at a first time slot and a second set of subcarriers of the plurality of the disjoint subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, the first set of the subcarriers of the plurality of the disjoint subcarriers being different than the second set of the subcarriers of the plurality of the disjoint subcarriers. 30. The base station as claimed in claim 21, wherein the controller is further configured to: allocate an additional coherence cluster to the second subscriber for use at the same time as the allocated coherence cluster; andprovide an additional coherence cluster identification to the second subscriber, which specifies the additional coherence cluster allocated by the base station.
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