 major issues on an international basis. Chapter 13 Wireless Communications Basics The regulatory aspect of radio communications covers two major areas: politi- cal issues, including regulation and spectrum allocation, and spectrum management (also known as frequency management), which involves several activities, two the most important being assignment and allocation. Assignment is the process selecting operating frequencies for radio equipment, ideally in such a way as to per- mit each system to operate without causing harm (interference) to other systems or receiving interference from them. Allocation refers to the process of determining what radio services-for example, what types of station (such as radar, broadcast TV, or amateur)-should operate in a particular band of frequencies. The radio spectrum is allocated on a country-by-country basis, SO that the spectrum available to various wireless systems varies by region. Balancing compet- ing claims is an important part of the allocation process. Within each nation, the government often claims a significant amount of spectrum for a variety of public safety and military applications. Regulatory agencies allocate radio spectrum into licensed and unlicensed bands. The use of licensed spectrum is an exclusive right to use a particular band of frequencies in a particular geographic market, with those licenses typically being sold at auction. Licensed spectrum is most com- monly used by mobile telephone, wireless local loop, and wireless DSL providers. Of course, many argue that this is roughly the equivalent of having to pay for something that already belongs to the public. More healthy debate is needed about the enormous amounts of money the government earns by charging for these licenses. What value does that government income bring to citizens, who ulti- mately pay for it through higher rates charged by wireless operators? Regulatory agencies also leave large portions of spectrum unlicensed. Anyone is allowed to build products that operate in unlicensed spectrum