Lesson 3 of CWA Course 2231 Wireless Fundamentals
20 minutes running time.
Every country has the sovereign right to manage energy at radio frequencies in its territory. When the airspace through which the radio waves travel is public property (which is most of the time), and there is contention for its use (which is all of the time), regulation is required to allow the rational use of the shared resource.
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The range of radio frequencies, called the radio spectrum, is divided into blocks of frequencies allocated for different services. Allocations are divided into allotments, which are bands of frequencies assigned to specific users or to the public. A license to emit radio-frequency energy at the specified frequencies in a specified area is issued by government to record the assignment of the allotment and the conditions for its use.
… these lesson notes continue on page 19 of the CWA Study Guide.