Optimizing Wireless Interconnection Network Costs

Abstract

The total cost of the fixed infrastructure thatunderlies a wireless network can be visualized ascomprising three cost elements: switching, radioports,and interconnection of switching/control centers and the radioports. Until recently,interconnection cost has represented only about 10% ofthe total network investment, the bulk of the cost beingincurred by the switching and radio equipment.Accordingly, optimizing the costs of the interconnectingnetwork has not received much interest. However, networkeconomics are changing. PCS technology and densecellular system populations require more radioports, located more closely to one another, than haspreviously been common. The number of subscribers and/orradioports that may be controlled from a single basestation controller (BSC) is increasing, thereby reducing the relative costs of those elements.In turn, interconnection cost is becoming a largerpercentage of the total system cost than has previouslybeen customary. Thus, methods for analyzing and optimizing the cost of the interconnectionsegment may now be useful. This paper presents a modelfor the interconnection cost of a wireless network anddemonstrates that there exists a single optimum location for the control center in such a network. Wedevelop a methodology for analyzing and optimizinginterconnection costs by locating the optimal locationof the BSC, exploiting the characteristics of the cost function, which is shown to be convex. Theresults are general and are not restricted to anyparticular form of cellular network.