in small- cell areas as in large-cell areas. The border activity affects call setup as well as handoffs, but with a lower volume of signaling. When a call starts near an MSC border so that it is detected by cells on mul- tiple MSCs, the MSCs all contact the home location register (HLR) for a decision about who is going to serve the call. This border-zone call-setup signaling activity is also in proportion to the traffic in the border zone. Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Signaling Capacity Planning Signaling Capacity Planning To estimate the amount of inter-MSC handoff signaling traffic, we need a good esti- mate of the total subscriber traffic in the inter-MSC border zones. This estimate can come from a careful population study with maps or it can come from planning tools, but the estimate of inter-MSC handoff signaling starts with an estimate of how much traf- fic is in the MSC border zones. This estimate should be calculated for each MSC and, preferably, for each pair of MSCs sharing a common border. Once we have the estimate of how much border-zone traffic is being served, we need an estimate of how much handoff signaling activity is being generated. In Sec. 15.1 we go over the various handoff activities and how many ANSI-41 signaling messages each generates. The rate of these activities for border-zone traffic has to be estimated based on radio conditions and code division multiple access (CDMA) experience, including lo- cal experience if there has ever been a CDMA system in the area. The result of this calculation is the best estimate we can form, given what we know about the system borders, for how much inter-MSC handoff activity there will be and how much ANSI-41 signaling that handoff activity will generate. In addition to planning MSC boundaries within our own system, we also must plan the boundaries between our sys