hus the only decisions for the service provider are when and where to replace cdmaOne base station equipment with cdma2000 equipment. This decision should be driven primarily by the market for 3G services rather than the need to expand voice channel capacity because of the compatibility between the two systems. There is some improvement in voice capacity with cdma2000, but most or all of it is only realized when subscribers switch to cdma2000 user terminals supporting the re- verse pilot. If the only argument for replacing a system were the increased capacity for voice calls, then it probably would not be worth it. However, the compatibility issues and the data-market opportunity both make conversion to cdma2000 a more favorable decision. What may be the most important issue in changing cdmaOne to cdma2000 is man- aging the expectations of subscribers expecting 3G services. If marketing efforts for data services run too far ahead of reality, then we can disappoint subscribers antici- pating 3G services long before they are available. 8We are assuming that the CDMA air interface used for the migration is a 3G technology. It makes more sense to use cdma2000 rather than cdmaOne because cdma2000 supports cdmaOne user terminals. 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 Base Station Planning 33.8 Quality and Cost Issues in Air-Interface Planning In our discussion so far we have talked about meeting demand as some kind of ab- solute. We have so many erlangs of demand for each service offering, and here is what we have to do to satisfy that demand. In fact, we have some broader choices to make- how we are going to manage the bigger tradeoffs of quality versus cost in planning the air interface. The attitude that quality is an absolute standard runs deep in the telephone culture, from way back in the Bell System days. 9 W