Graw-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. Turning User Complaints into Useful Data Turning User Complaints into Useful Data does not work, but we are writing about perfectly good, working equipment that is not delivering the service we want to offer. The system may not be delivering the quality of service (QoS) that is required for subscriber community. For voice traffic, we can have too many blocked calls, too many lost calls, or too many lousy calls. For data traffic, we can have too many blocked calls, too much delay, or too many errors. These may be concentrated in specific geographic areas that require improved coverage. These are the red areas we described at the be- ginning of this chapter, areas of such low radio path gain that they cannot be served well with the antenna faces currently in place. We can adjust, modify, or add radio equipment to provide service to these hard-to-reach areas. The QoS problems may be associated with high-demand times of day. If entire cell sectors are affected, then we have a green area as described earlier with a CDMA car- rier whose fundamental, mathematical capacity limit is too low for subscriber demand. If partial cell sectors are affected and the QoS problems expand geographically as the traffic increases, then we have a yellow area, a CDMA carrier reaching its limit on the coverage-and-capacity frontier. Either of these cases is relieved by adding more CDMA capacity, more carriers, more sectors, and more cells. The yellow-area case also can relieved by improving the radio signal paths with more or better radio equipment such as higher-gain antennas or repeaters. The system may be working fine today, but growth in demand makes it likely that it will not be working well fairly soon. This is a good problem to have, more subscribers wanting to pay for our wireless telephone service. However, it means that we need add capacity to our system eve