RESOURCE SCHEDULING IN WIRELESS COMMUNICATION SYSTEMS USING BEAM FORMING

• US 20090258654A1
• Filed: 12/21/2006
• Published: 10/15/2009
• Est. Priority Date: 07/07/2006
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Hagerman, Bo
• Granted Patent: US 8,135,439 B2
• Time in Patent Office: Days
• US Class Current: 455/452.100
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

A basic idea of the invention is to provide multi-user resource scheduling and distribution based on balancing the power resources used for the different narrow beams in order to smooth the interference levels over the whole cell, area and to reduce interference fluctuations. The resource scheduling principle according to the invention is especially useful when the available resources are not fully utilized. The idea is to select, for each antenna beam of at least a subset of the antenna beams, at least two mobile users for service using the respective antenna beam during a transmission time interval, and to distribute power resources to the antenna beams for use during the transmission time interval based on the guideline of balancing the power resources among different antenna.

Claims

1. A method for multi-user resource scheduling in a radio communication system having a radio base station with narrow beam capabilities, wherein said method is based on selecting multiple mobile users to be scheduled for service using multiple narrow antenna beams during a predetermined transmission time interval, characterized by:

selecting, for each antenna beam of at least a subset of said multiple antenna beams, at least two mobile users for service using the respective antenna beam during said transmission time interval; and

distributing power resources to the antenna beams for use during said transmission time interval based on balancing the power resources among different antenna beams, wherein said narrow antenna beams are partially overlapping, and said step of

distributing power resources to the antenna beams comprises the step of allocating, when there are no active mobile users in a given beam, more power resources to antenna beams that are direct neighbors of the given antenna beam than to more distant antenna beams to balance the power resource distribution over the whole area covered by the cell.

2. The method of claim 1, wherein the power resources are distributed among the different antenna beams in order to smooth the interference levels over the whole area covered by the cell and to reduce interference fluctuations.

3. The method of claim 1, wherein said step of selecting comprises the steps of providing a ranking list of mobile users in a cell and at the same time keeping track of spatial information represented by the narrow antenna beam in which each mobile user is located.

4. The method of claim 1, wherein said selecting step comprises the steps of selecting a best ranked mobile user from the ranking list for service by a given narrow antenna beam, and then traversing the ranking list to select the following users not only by looking at the position in the ranking list but also by considering the spatial information so that a next user down in the list is located in another narrow antenna beam different from that of previously selected user(s) higher up in the ranking list, and once the end of the list is encountered the selection procedure starts over at least one time from the top of the list to select further mobile users.

5. The method of claim 1, wherein said steps of selecting and distributing are performed for each transmission time interval.

6. The method of claim 1, wherein at least one user is associated with a number of different services, and these services are scheduled based on balancing the power resources among different antenna beams such that the number and/or types of services that are scheduled for said at least one user vary over time in dependence on the available resources.

7. An arrangement for use in a cellular radio communication system, said arrangement having means for generating multiple antenna beams associated with a communication cell, each beam covering only a portion of the cell, and means for selecting multiple mobile users to be scheduled for service using multiple antenna beams during a predetermined transmission time interval, characterized by:

means for selecting, for each antenna beam of at least a subset of said multiple antenna beams, at least two mobile users for service using the respective antenna beam during said transmission time interval; and

means for distributing power resources to the antenna beams for use during said transmission time interval based on balancing the power resources among different antenna beams,

wherein said narrow antenna beams are partially overlapping, and said

means for distributing power resources to the antenna beams comprises means for allocating, when there are no active mobile users in a given beam, more power resources to antenna beams that are direct neighbors of the given antenna beam than to more distant antenna beams to balance the power resource distribution over the whole area covered by the cell.

8. The arrangement of claim 7, wherein said means for selecting comprises means for providing a ranking list of mobile users in a cell and for keeping track of spatial information represented by the narrow antenna beam in which each mobile user is located.

9. The arrangement of claim 7, wherein said means for selecting is operable for selecting a best ranked mobile user from the ranking list for service by a given narrow antenna beam, and traversing the ranking list to select the following users not only by looking at the position in the ranking list but also by considering the spatial information so that a next user down in the list is located in another narrow antenna beam different from that of previously selected user(s) higher up in the ranking list, and once the end of the list is encountered starting the selection procedure over at least one time from the top of the list to select further mobile users.

10. The arrangement of claim 7, wherein said arrangement is implemented in at least one network node of said radio communication system.

11. The arrangement of claim 10, wherein said at least one network node includes a radio base station.