Patent ID: 8989016
Filing Date: 2015-03-24
Classification: H04B,H04L,H04W

Abstract:
1. A method for use in selecting a cell or cells, from amongst a set of cells in a cellular wireless network, for coordinated use in multi-cell multiple-input/multiple-output (MIMO) transmission so as to reduce feedback overhead, each cell of the set of cells having at least one MIMO channel characteristic which can vary with time at a measurable rate, the method comprising a cell selection process comprising: identifying the cell or subset of cells of the set of cells for which time variation rate or rates of the at least one MIMO channel characteristic is slowest of the cells in the set of cells; and selecting the cell or cells for use in the multi-cell MIMO transmission from only the cell or subset of cells identified; wherein a preselection process is carried out before the identifying, in which process cells of the cellular wireless network are preselected for inclusion in the set of cells if signals received from the cells at a specific receiver are consistent with achieving a target coordination gain; and the method further comprising carrying out, after passage of an interval from the selection of the cell or cells for use in the multi-cell MIMO transmission of an immediately-preceding cell selection process, an updating process of: determining whether the time variation rate or rates of the at least one MIMO channel characteristic for a cell or any of the cells selected in the immediately-preceding cell selection process have changed by a preselected amount from the time variation rate or rates used in the immediately-preceding cell selection process for the selected cell or cells; if such a change is determined to have occurred, repeating the preselection process; and if a set of cells can be preselected in the preselection process, repeating the cell selection process.