ing to prove the safety of hydrogen first reproduced their work and then uncovered the records that dated from shortly after the explosion. The point is that particularly when it comes to fads, we cannot count on what is pop- ular in one country moving to another. And even if it does become popular in another country, it is a very open question whether it will be popular enough to be profitable. Adding a new feature to a nationwide cellular network in Japan is a much smaller ven- ture than doing the same in the United States. And the same is true if we want to make the service available only in major metropolitan areas. 49.1.5 The rest of the world The economic challenges that most cellular equipment providers are facing probably make them cautious about investment in countries with weaker economies and less 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. CDMA Now and in the Future Conclusion stable governments. The development of cellular services, whether for mobile use or for wireless local loop (WLL), probably will be slow. It may well be driven more by inno- vative entrepreneurs who understand the local culture and tap Western engineering expertise than we might expect. Despite strong doubts from financial backers, an in- novative thinker has launched a successful cellular telephone service in rural Pakistan. The key to success was an innovative approach to billing and marketing. The owner of the phone can allow use by others on a call-by-call basis and charge them for it. As a result, the owner can subsidize personal use by income obtained through short-term rental of the service to others. This initial success relied on an entrepreneur who knew the culture and got an advanced engineering and business education in the United States. However, now that the method is succeeding, it will be easier to reproduce else- where. We should expect