The need to measure man-made radiation from orbit for spectrum management

Introduction The spectrum is a natural resource which has been valueed at $4 billion per megahertz. When the supply of spectrum exceeds the demand, spectrum management can be non-existent. As time progresses, the supply/demand ratio continues to allow implementation of necessary services. This need was formally recognized fifty years ago with the formation in 1922 of the Interdepartment Radio Advisory Committee (IRAC) to make effective use of radio frequency assignments to Government stations. Today there are over 120,000 assignments, and there are over 50,000 new applications annually (1). With this tremendous number of transmitters, Management of the radio spectrum is a complex multi-agency function. Monitoring of the radio frequency spectrum is required by the spectrum managers to (a) only authorized users are radiating, (b) that these radiations within the authorized limits, and (c) that the spectrum is allocated optimally.