Long Distance Co-Channel Interference to Land Mobile Reception at 450MHz,

摘要

During the course of gathering data in the Washington area for the report entitled Examination of the Feasibility of Conventional Land Mobile Operations at 950MHz (Research Division Report R-7102),signals radiated from our Base Station caused 450MHz interference to base station reception at Philadelphia. The frequent recurrence of this interference prompted the inauguration of a one year recording project. Our recorded data was approximately 6dB above the curve describing other long term data previously reported in FCC Report R-6602. The highest signal levels consistently occurred during the early morning hours of the summer months. This type of long distance interference is caused by super-refraction or trapping in ducts and is known to be related to climatic conditions. The data contained in this report cannot be extrapolated to other paths even of the same distance.