Measurement of the effect of irregular terrain on VHF and UHF directive antenna patterns

Abstract

Measurements of antenna patterns of directive antennas were made while driving around transmitters at relatively constant distances of 0.4, 10, and 30 miles. The transmitting antennas for pattern measurement were located at Fort Dix, N.J., and operated at frequencies of 49, 141.75, 239, and 460 mc. The receiving antennas used for recording were ground-plane antennas mounted on a retractable mast in the mobile recording unit and could be operated as high as 30 feet, road obstacles permitting. Because of the great number of wires and trees over the road, most measurements were made at 12 and 15 feet. In addition to the measurements made around the transmitters, receiving antenna pattern measurements were made at spot locations around the transmitter with a 460-mc corner reflector antenna.