An apparatus and method for describing channel resources comprising allocating channel resources for a plurality of tiles; and determining a description of the channel resources allocated for a tile of the plurality of tiles by performing one or more of the following steps: a) comparing the size of the tile to a tile size threshold (THsize) to determine if the size of the tile is small or large; b) comparing the allocation of the channel resources to the tile to an allocation threshold (THallocation) to determine if the allocation of the channel resources is sparse or not sparse; and c) determining if the allocation of the channel resources within the tile is regularly spaced or not regularly spaced.