nclusion With a model of our system and a sense of the locations of our subscribers, we can trou- bleshoot problems using both simulation and analysis. We also can use these systems to plan growth. Growth is becoming more complicated as we begin to provide a variety of services over the air interface. CDMA is not just for telephone calls any more, but it remains to be seen what data services will be popular. The level of demand will be a key factor for income, and the ability to serve that demand when and where it is located will be key to success in the increasingly competitive cellular market. A business with more accurate models of its systems and customers and better ability to link engineer- ing plans and requirements with business requirements and plans has a much better chance of succeeding. Such a company is more likely to allocate scarce resources for growth to the most important new services and to end up with more profitable business operations. Soon we may be able to leverage systems that locate our subscribers during calls. This would allow us to populate our simulations with even more accurate data and de- rive more accurate results. New and upcoming technologies like this, as well as the challenges facing the cellular industry as a business, are the topic of our final chapter. 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. Subscriber Traffic Modeling 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. Source: CDMA CAPACITY AND QUALITY OPTIMIZATION Conclusion Engineering is only one essential part of a successful code division multiple access (CDMA) wireless network. As engineers, we serve our companies best by understanding a variety of business issues and a