| Popis: |
Radio frequency interference has been a particularly difficult area for achieving effective standardization, principally because of technical considerations, but also because it is of concern to so many interests and activities. Prior to World War II, standardization efforts were mainly confined to the medium-frequency broadcast band. During the war it became evident that the problem must be considered on a much broader basis. More recently, highly critical systems being used in space research have placed additional requirements on system engineering for interference-free operation. Radio frequency interference can mean the difference between success and failure of a costly space project. There are four general categories in which standardization efforts are required: 1) terms and definitions, 2) measurement methods, 3) instrument characteristics, and 4) interference limits. Various professional, industrial, and governmental organizations are working at both national and international levels on standards in these areas. |
