Transmission power range setting during channel assignment for interference balancing in a cellular wireless communication system
View Patent ↗The present invention relates to a method for balancing the distribution of interference between radio cells in a wireless communication system comprising cells in which subcarrier blocks are used for communication. A number of adjacent cells build a cell cluster. Moreover, the present invention relates to a corresponding method adapted for use in a system in which multi beam antennas or multiple antennas are used. Furthermore, the present invention relates to base stations performing the above method as well as a communication system comprising the base stations. To reduce the large average SIR variations without causing additional SIR estimation, measurement and calculation problem as introduced with power control the invention suggests to group subcarrier blocks into a plurality of subcarrier block sets in each cell of a cell cluster, to determine transmission power ranges for each of the cells of said cell cluster, and to assign transmission power ranges to the subcarrier block sets to perform TPC within the ranges.
1. A base station for use in a wireless communication system, the system comprising radio cells, wherein each radio cell comprises a plurality of subcarrier blocks, each subcarrier block comprising a plurality of subcarriers, the base station comprising:
a processing unit that groups the subcarrier blocks of a radio cell controlled by the base station into a plurality of subcarrier block sets, wherein the radio cell and its adjacent radio cells in the wireless communication system build a cell cluster, and each cell in the cell cluster comprises corresponding subcarrier block sets having the same subcarrier blocks, and
an assigning unit that assigns transmission power ranges to the plurality of subcarrier block sets, respectively, wherein a transmission power range defines a range of transmission power levels used for transmission power control, wherein at least one of the subcarrier block sets in the radio cell controlled by the base station is assigned a different transmission power range than other subcarrier block sets in the radio cell controlled by the base station.
2. The base station according to claim 1 , wherein at least one of the subcarrier block sets in the radio cell controlled by the base station is assigned a different transmission power range than another corresponding subcarrier block set in another cell of the cell cluster.
3. The base station according to claim 1 , wherein the processing unit groups the subcarrier blocks into subcarrier block sets in a non-consecutive fashion.
4. The base station according to claim 1 , where the processing unit groups subcarrier blocks in predetermined intervals to a respective subcarrier block set.
5. The base station according to claim 1 , wherein the processing unit groups the subcarrier blocks based on configuration information received from a control unit in the wireless communication system.
6. The base station according to claim 1 , further comprising a scheduler that allocates a subcarrier block of a subcarrier block set being assigned a high transmission power range to a mobile terminal having a low signal to interference ratio.
7. A method for assigning transmission power ranges in a wireless communication system, the system comprising radio cells, wherein each radio cell comprises a plurality of subcarrier blocks, each subcarrier block comprising a plurality of subcarriers, the method comprising:
grouping the subcarrier blocks of a radio cell controlled by the base station into a plurality of subcarrier block sets, wherein the radio cell and its adjacent radio cells in the wireless communication system build a cell cluster, and each cell in the cell cluster comprises corresponding subcarrier block sets having the same subcarrier blocks, and
assigning transmission power ranges to the plurality of subcarrier block sets, respectively, wherein a transmission power range defines a range of transmission power levels used for transmission power control, wherein at least one of the subcarrier block sets in the radio cell controlled by the base station is assigned a different transmission power range than other subcarrier block sets in the radio cell controlled by the base station.
8. The method according to claim 7 , wherein the processing means is adapted to group the subcarrier blocks into subcarrier block sets in a non-consecutive fashion.
9. The method according to claim 8 , wherein at least one of the subcarrier block sets in the radio cell controlled by the base station is assigned a different transmission power range than another corresponding subcarrier block set in another cell of the cell cluster.
10. The method according to one of claim 7 , where the processing means is adapted to the group subcarrier blocks in predetermined intervals to a respective subcarrier block set.
11. The method according to claim 7 , wherein the processing means is adapted to group the subcarrier blocks based on configuration information received from a control unit in the wireless communication system.