Andrew Farrar; Herb Dobson; Fredrick Wentland

Abstract: Several methods for estimating the potential interference from systems in the Fixed Service to Power-Line–Carrier (PLC) circuits were developed. The Numerical Electromagnetic Code (NEC) computer program, originally developed by the Navy, was used to calculate the electric field intensity of the PLC radiated from a number of representative electric transmission lines. Measured field intensity data, obtained from five different geographical sites in the United States, were compared with the calculated results obtained using the NEC computer model and the agreement was found to be acceptable. In addition, the NEC program was used to estimate the coupling factor between the antennas of Ground Wave Emergency Network (GWEN), a system being developed by the U.S. Air Force, and a representative electric transmission line used for PLC applications in the United States. Interference threshold levels for PLC receivers were established from the test data, and corresponding field intensities near a transmission line that can produce those levels were calculated. Rules and regulations pertaining to the systems in the, Fixed Service in the 150–190 kHz frequency range were reviewed and no regulatory problems were identified relative to the operati.on of PLC and systems in the Fixed Service in this frequency range.

Keywords: compatibility between PLC systems and radio transmitters; GWEN system; interference analysis model; numerical electromagnetic code (NEC); power-line-carrier system; radiated field from power transmission lines; systems in the 150-190 kHz

To request a reprint of this report, contact:

Ed Drocella, Chief,
Spectrum Engineering and Analysis Division
Office of Spectrum Management
National Telecommunications and Information Administration
(202) 482-1652

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.

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