Spectrum Management for Science in the 21st Century
Автор:Committee on Scientific Use of the Radio Spectrum, Committee on Radio Frequencies, National Research Год: 2010 Издание: [не указанo] Страниц: 160 ISBN: 0309146860 Radio observations of the cosmos are gathered by geoscientists using complex earth-orbiting satellites and ground-based equipment, and by radio astronomers using large ground-based radio telescopes. Signals from natural radio emissions are extremely weak, and the equipment used to measure them is becoming ever-more sophisticated and sensitive. The radio spectrum is also being used by radiating, or "active," services, ranging from aircraft radars to rapidly expanding consumer services such as cellular telephones and wireless internet. These valuable active services transmit radio waves and thereby potentially interfere with the receive-only, or "passive," scientific services. Transmitters for the active services create an artificial "electronic fog" which can cause confusion, and, in severe cases, totally blinds the passive receivers. Both the active and the passive services are increasing their use of the spectrum, and so the potential for interference, already strong, is also...
