OFDMA WITH ADAPTIVE SUBCARRIER-CLUSTER CONFIGURATION AND SELECTIVE LOADING
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.
1 . A method for a wireless system, the method comprising:
receiving, at a subscriber unit, an allocation of a group of clusters selected by a base station for use by the subscriber unit, the receiving of the allocation of the group of clusters including receiving a group index from the base station, at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters, each cluster of the group of clusters including a plurality of subcarriers.
2 . The method of claim 1 , wherein the plurality of subcarriers is a plurality of consecutive subcarriers.
3 . The method of claim 1 , wherein disjoint clusters of the group of clusters are spread farther apart from each other than a coherence bandwidth of a respective channel.
4 . The method of claim 1 , wherein the at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters to obtain frequency diversity.
5 . The method of claim 1 , wherein the plurality of subcarriers includes a first set of subcarriers at a first time slot and a second set of subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, at least one subcarrier of the first set of subcarriers at the first time slot being different than all subcarriers of the second set of subcarriers at the second time slot.
6 . A subscriber unit in a wireless system, the subscriber unit comprising:
a processor configured to:
receive an allocation of a group of clusters selected by a base station for use by the subscriber unit, the processor configured to receive the allocation of the group of clusters including receipt of a group index from the base station, at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters, each cluster of the group of clusters including a plurality of subcarriers.
7 . The subscriber unit of claim 6 , wherein the plurality of subcarriers is a plurality of consecutive subcarriers.
8 . The subscriber unit of claim 6 , wherein disjoint clusters of the group of clusters are spread farther apart from each other than a coherence bandwidth of a respective channel.
9 . The subscriber unit of claim 6 , wherein the at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters to obtain frequency diversity.
10 . The subscriber unit of claim 6 , wherein the plurality of consecutive subcarriers includes a first set of subcarriers at a first time slot and a second set of subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, at least one subcarrier of the first set of subcarriers at the first time slot being different than all subcarriers of the second set of subcarriers at the second time slot.
11 . A method for a wireless system, the method comprising:
providing, at a base station, an allocation of a group of clusters selected by the base station for use by a subscriber unit, the providing of the allocation of the group of clusters includes providing a group index from the base station, at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters, each cluster of the group of clusters including a plurality of subcarriers.
12 . The method of claim 11 , wherein the plurality of subcarriers is a plurality of consecutive subcarriers.
13 . The method of claim 11 , wherein disjoint clusters of the group of clusters are spread farther apart from each other than a coherence bandwidth of a respective channel.
14 . The method of claim 11 , wherein the at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters to obtain frequency diversity.
15 . The method of claim 11 , wherein the plurality of consecutive subcarriers includes a first set of subcarriers at a first time slot and a second set of subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, at least one subcarrier of the first set of subcarriers at the first time slot being different than all subcarriers of the second set of subcarriers at the second time slot.
16 . A base station in a wireless system, the base station comprising:
a processor configured to:
provide an allocation of a group of clusters selected by the base station for use by a subscriber unit, the processor configured to provide the allocation of the group of clusters includes providing of a group index from the base station, at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters, each cluster of the group of clusters including a plurality of subcarriers.
17 . The base station of claim 16 , wherein the plurality of subcarriers is a plurality of consecutive subcarriers.
18 . The base station of claim 16 , wherein disjoint clusters of the group of clusters are spread farther apart from each other than a coherence bandwidth of a respective channel.
19 . The base station of claim 16 , wherein the at least one cluster of the group of clusters being disjoint from all other clusters of the group of clusters to obtain frequency diversity.
20 . The base station of claim 16 , wherein the plurality of consecutive subcarriers includes a first set of subcarriers at a first time slot and a second set of subcarriers at a second time slot, the second time slot being immediately subsequent to the first time slot, at least one subcarrier of the first set of subcarriers at the first time slot being different than all subcarriers of the second set of subcarriers at the second time slot.