IEEE 1260:1996 (R2007)

New IEEE Standard - Superseded.
A set of procedures to be followed to cope with reradiation of AM broadcast signals from power lines and other large metallic structures is provided. Reradiation may be described as electromagnetic waves radiated from a structure that has parasitically picked up a signal from the environment. A simplified prediction technique called a survey is described to determine which structures could possibly cause a problem. Guidelines for measurements and data analysis are included.

This guide provides a set of procedures to be followed to cope with reradiation of AM broadcast signals from power lines and other large metallic structures. An AM broadcast array is carefully constructed to radiate strongly towards listeners and weakly in directions where interference to other stations could result. Reradiation can occur when the broadcasted signals are parasitically picked up by a large metallic structure and then rebroadcasted, or reradiated, from that structure. This can result in a decrease in signal towards listening areas and an increase in signal in protected directions. The process of predicting, measuring, and analyzing the interference is complex and nontrivial, necessitating this guide.
This guide is divided into the following sections: interference prediction and limitations, guidelines for taking meaningful field strength measurements, methods of analyzing the field strength measurements, and short sections on the application and verification of remedial measures. A series of annexes accompany the guide in order to illustrate the complex analysis.