e CDMA channel for high- speed data bursts may displace more voice calls than the steady-stream user. The higher variability of a bursty usage pattern reduces the capacity of the CDMA air interface. Real-time video and Web surfers both use high bit rates, but the Web surfer may tol- erate delays of a second or two that would be unacceptable in a real-time video call. Thus, on a busy packet channel, the low-delay video caller may be displacing more voice calls so that we can maintain the high packet rates necessary for low delay. These high-rate services displace other revenue. How much revenue they displace depends on the mix of services being used and the quality of service (QoS) we are try- ing to provide. How much revenue they earn depends on the demand for these services and the competition in the market. High-rate 3G services cost the least to provide at off-peak times, of course, and in the targeted areas. If we are going to promote 3G services, especially services that use a lot of CDMA air-interface resources, then we would like to encourage that growth where we already have capacity or where we can easily get backhaul transport. We can control the mix of services through price promotions and product packages. In Sec. 38.2 we discussed the problem of entering a market for new services. We ex- plained that raising consumer interest in a new product often requires selling that 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. Regional Growth in a Specific Area Regional Growth in a Specific Area product very cheaply and making promises that are hard to keep in the long run. Here is a case where we can promote a new service that costs us very little in a specific re- gion by selling it cheaply in that region. As subscribers get used to using the new ser- vices, they will want to use those same services in the more expensive areas and may b