Heuristics for assignment of cells to switches in a PCSN: a comparative study

This paper presents a comparative study of various heuristics proposed to solve the problem of optimally assigning cells to switches in a personal communication services (PCS) network. In the literature, this problem is known as cell-to-switch assignment (CSA) and has been conventionally formulated as an integer programming problem. However, because of the time complexity of the problem, the solution procedures are heuristics, especially when the number of cells and switches are large. The common objective of these assignment heuristics is to minimize the hybrid cost comprising handoff cost between adjacent cells and cable cost between cells and switches. The constraint to be obeyed in all such assignments is that the call volume to be handled by a switch should not exceed the traffic handling capacity for which the switch is designed for. In this paper, we have proposed a few novel assignment heuristics and compared them with other existing ones in respect of execution time and total hybrid cost. Our results indicate that there is no single heuristic that performs equally well in terms of cost and execution time. However, heuristic IV can be identified as the one which is less costly than most of the other heuristics whereas heuristic VI is the fastest of all.