FREQUENCY PLAN THAT ACCOMMODATES DEMAND GROWTH

摘要

A frequency allocation plan for a wireless communication system that accommodates growth in demand from a low density reuse pattern of twelve cells to a high efficiency reuse pattern of three cells. The available radio spectrum is first divided into three ranges and each range is further divided into four groups. The frequencies in each range are sequentially assigned to the four groups. The groups are further identified as even and odd groups. The twelve cell groups are laid out in rectangular shapes of four cells wide by three cells high, with a first set of three cells in the upper left portion being assigned to use a first even index frequency group. A second group of three cells in a lower left portion are assigned to use a second even index frequency group. A third and fourth group of cells associated with upper right and lower right positions are assigned the first and second odd index frequency group. As traffic density increases the cells are split into six sectors with each sector being assigned the other odd or even frequency group to achieve a reuse factor of six. Sectorizing to a cell reuse pattern of three is then implemented by swapping the resulting frequency assignments made to a leftmost column of three cells with a non-adjacent center column of a cell group to the left. In order to implement times three reuse in the rightmost column of cells, odd and even frequency assignments are similarly swapped between the leftmost column and the non-adjacent center column of the cell group to the right.