MOBILE MILLIMETER WAVE TRANSMISSION LINE FOR NEAR-FIELD ANTENNA MEASUREMENTS

Abstract

Issues of design and creation of the mobile line of transmission of a millimeter wave range are considered. The work is aimed at further investigation of the line for its application in automatic measuring complexes of amplitude-phase distribution on the plane of near-field an- tennas of the corresponding range. The proposed mobile line transmits the signal through the section "scanned probe-stationary measuring equipment" and is built on the segments of superdimensional waveguides connected by their movable joints. It is able to provide the length of the probe scanning in the plane to a distance of 1000 mm. On the other hand, such a transmission line, which is essentially quasi-optical, can provide small attenuation of the mil- limeter wave range signals and universality of its application in the entire range of that range. For sufficient stability (in amplitude and phase) of the transmitted signal, the geometric length of the movable line remains unchanged during the measurement process. The invariance of length is provided by the method of simultaneous trombone compensation for changes in its length. The application of the proposed mobile signal transmission line of millimeter waves and automatic measuring systems for measuring the amplitude-phase distribution of the near field of antennas of the mentioned range will allow to determine the parameters of the direc- tional antennas (the width of the main lobe of the directional diagram within 0.1° ...1°), which are widely used in radar, radio navigation systems and in communication systems, sensing and passive radio vision of the millimeter wave range․ The creation of such a transmission line with sufficiently stable transmission characteristics is part of the development of technology for measuring the amplitude-phase distribution of the near-field antennas of the millimeter wave range.