January 1981 | NTIA Technical Report TR-81-58
Transportable Automated Electromagnetic Compatibility Measurement System (TAEMS)
Charles J. Chilton; A. H. Diede; W. M. Welch; Robert A. McLean; Frank G. Stewart
Abstract: An automated, computer–controlled receiver system developed by ITS for the U.S. Army Communications Command provides a unique solution to such problems as spectrum management, EM hazards measurements, and site surveying. This receiving system is designed around a commercially available automatic receive system and covers the frequency band 1 kHz–40 GHz, thus extending the capability of the receiver system by providing extended frequency coverage, multiple antenna selection, improved noise figure performance, built–in test capability, noise figure measurement capability, and l60dB measurement range; as well as 10 Hz frequency resolution to 40 GHz, computer controlled directional antenna pointing, and automatic real–time calibration to 40 GHz. Three rf preselector/down converters were developed by ITS for use with the receiver to cover frequencies between 2 and 40 GHz. High sensitivity and low transmission loss was achieved by attaching the down converters directly to the antennas and mounting the complete system package on the elevation/azimuth (ELI AZ) positioner. The down converters mix the rf signals to IF (150 MHz), and this IF signal is transmitted through the EL/AZ pedestal via coxial cable to the bus structure interface unit, mixed to 50 MHz and then fed to the rf–microwave section of the automatic spectrum analyzer for further processing. In addition, a real–time–executive (RTE) software operating system was developed for the receiver system by ITS to extend the operating capability of the receiver system. The RTE allows multiprogram execution, as well as program scheduling, file manipulations, and editing. Using the editor, FORTRAN measurement routines can quickly be written or modified. Both source and object programs are stored on magnetic disc with measurement data stored on magnetic tape for further analysis.
Keywords: electromagnetic compatibility (EMC); spectrum management; computer controlled receiver; 1 kHz to 40 GHz; EM hazard measurement
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Disclaimer: Certain commercial equipment, components, and software may be identified in this report to specify adequately the technical aspects of the reported results. In no case does such identification imply recommendation or endorsement by the National Telecommunications and Information Administration, nor does it imply that the equipment or software identified is necessarily the best available for the particular application or uses.