ry their calls more often. Another tactic in the quality-of-service game is to delay service rather than to refuse it. If a busy CDMA sector has 100 calls on it and the average call is 200 seconds long, then the average time until somebody ends a call is 2 seconds. We may decide that sub- scribers would rather wait 2 seconds than be told that the system is not available and 9 At least, that was how things were here in the United States. 10 One of us (Rosenberg) worked for Bell Telephone Laboratories in the old Bell System days. 11Apparently this has not caused a subscriber shift away from wireless and back to their land- line telephones. The airlines, for example, have avoided a similar advertising campaign where one airline would exploit the poor safety record of another. The effect of such advertising probably would be to heighten fear of flying and keep people from buying airline tickets on any airline. 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. Base Station Planning Planning for CDMA Capacity to try again later. Allowing a few seconds delay in placing a call allows a higher occu- pancy on the CDMA carrier and allows us to operate closer to full utilization. This may be particularly useful in data service, where subscribers are already accustomed to waiting several seconds for a session. In Sec. 22.3 we discussed the concept of a feasible region of possibilities, all the choices we are able to make in designing a system. On the boundary of that feasible space is a frontier, a region of possibilities where any change we make has to degrade some aspect of the system. The frontier of wireless telephone service is defined by cost, quality, and quantity. In the big picture, these are the three components vying for our attention. In managing the tradeoff of three related components, one effective approach is to constrain one of the variabl