Antenna gain measurement methods in the far-field require that the antenna under test (AUT) be illuminated by a uniform plane wave. To achieve this uniform plane wave illumination, a very large distance between the antenna and the measurement source antenna is usually required. A compact antenna test range creates a plane wave field at distances considerably shorter than those needed under conventional far-field criteria. This shorter distance allows a compact range to be conveniently located near test or integration facilities and by placing it in a shielded anechoic chamber, interferences from external sources can be eliminated. The enclosed system is equally protected from weather conditions, and confidential information is better secured. Careful analysis of requirements and implementation of the appropriate compact range system within an efficiently sized anechoic chamber can result in a high-performance test zone and optimized antenna gain measurement method test results.
Over 30 years of engineering know-how goes into the design and manufacturing of compact range systems from MVG-Orbit/FR. This expertise carries through from the project analysis phase to implementation and installation. Precision, accuracy, and state-of-the-art techniques are in every piece of equipment we build, with proven results in the numerous systems continuously in use today.
Compact ranges provide an efficient means for obtaining a uniform plane wave illumination over a test object in a distance substantially shorter than in a comparable far-field range. Compact Ranges use a source antenna, which radiates a spherical wave, in conjunction with one or more reflectors to collimate this spherical wave into a plane wave.
Based on the geometrical-optical principle, the parabolic reflector needs precision in its design to achieve expected performance in a wide frequency range; from low frequencies where the compact range reflector is only a few wavelengths in size, up to very high frequencies where the reflector can reach hundreds of wavelengths. Consideration must also be given to the feed horn, and its positioning in relation to the reflector, as well as the absorber layout and separation distance between the absorbers and the reflector in the anechoic chamber.