Regulation plays a critical role in radio communications. In the early twentieth century, the first people experimenting with radio were largely amateurs. There were no laws or regulations until 1912. The first step to regulating the U.S. radio spectrum was adopted in August 1912, referred to as "An Act to Regulate Radio Communication."
In 1927, the international community formed the Consultative Committee on International Radio (CCIR), which was responsible for creating international radio standards and coordinating the technical studies, tests, and measurements being carried out in the various fields of wireless telecommunications. In 1932, the CCIR and several other organizations (including the original ITU, which had been founded as the International Telegraph Union in 1865) merged to form what became known as the International Telecommunication Union in 1934. The ITU is organized under the United Nations. In 1992, the CCIR became the ITU Radiocommunication Sector (ITU-R), a standards body subcommittee of the ITU. The role of the ITU-R is to regulate the allocation of radio frequencies and so reduce the interference between radio stations in various countries. Although the ITU-R works on coordinating spectrum allocation on a global basis, it does not have the authority to mandate that countries comply with its recommendations. The ITU-R also has responsibility for regulating orbital positions of satellites relating to radio communications. In addition, it publishes international engineering standard documents in its area of responsibility. The ITU-R also organizes the World Administrative Radio Conference (WARC), held periodically to address major issues on an international basis.
The regulatory aspect of radio communications covers two major areas: political issues, including regulation and spectrum allocation, and spectrum management (also known as frequency management), which involves several activities, two of the most important being assignment and allocation. Assignment is the process of selecting operating frequencies for radio equipment, ideally in such a way as to permit 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 servicesfor 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 competing 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 commonly 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 ultimately 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 bands, as long as they conform with specified regulations that govern use, such as observing the power limits. One of the complexities of building products for use in unlicensed spectrum is that not all countries have allocated the same bands for unlicensed operation. One of the biggest questions, and opportunities, in securing more spectrum for wireless systems lies in the spectrum currently allocated to the broadcast television industry. Depending on the country, a single TV channel occupies either a 6MHz or 8MHz transmission band, which is equal to 300 or more digital cellular channels.
Part I: Communications Fundamentals
Telecommunications Technology Fundamentals
Traditional Transmission Media
Establishing Communications Channels
Part II: Data Networking and the Internet
Data Communications Basics
Local Area Networking
Wide Area Networking
The Internet and IP Infrastructures
Part III: The New Generation of Networks
Broadband Access Alternatives
Part IV: Wireless Communications
Wireless Communications Basics
WMANs, WLANs, and WPANs
Emerging Wireless Applications