| 摘要 |
<p>A channel assignment system provides channel assignments to make effective use of the available frequency spectrum by assigning one channel at a time until all the channels in the allotted frequency spectrum are used. A pre-allocation step assigns specified channels to certain cells and these assignments are checked against initial input system constraints. Then the remaining channels are assigned one at a time to the cells according to defined system performance constraints and the number of channels required by each cell. Each cell is defined by its logical faces. The traffic load for each logical face is defined according to selected factors which may include call rates, blocking rates, handoff thresholds, access thresholds, call drop rates, etc. Given these factors the number of channels required by each logical face can be derived and input to the channel assignment system. A level of interference is determined for each logical face as caused by every other logical face by a signal matrix computer (410). Factors involved in this determination include geographical terrain, transmitting antenna properties transmission power and the location of individual cells. A signal-to-interference matrix is developed from this information. The individual channels are now assigned (420,440) to the logical faces based on the developed information including the number of channels needed at each logical face, the signal interference matrix and other system constraints (425). <IMAGE></p> |
