Abstract: Device and method for permanently checking the integrity of a transmission affected by parameters not directly accessible to measurement and whose influence on the modulus and phase of the field radiated in space can be determined by utilizing a mathematic model, the transmission being from an antenna array. Each antenna is supplied with one or more Hf carrier frequencies, each being modulated in a known way by one or more sinusoidal low frequency signals. First, a recording is made, at least at one point and during a time period T, of the amplitude of the combination of the signal received at this point and of a reference signal, having a fundamental frequency equal to one of the HF frequencies of the signal to be analyzed. Then, the amplitude of low frequency components of the signal thus obtained is extracted and memorized.

Abstract: The device for supplying a Doppler VOR system comprises means for generating the sidebands of an amplitude modulation of a VHF carrier wave, the signals representing the sidebands being amplitude-modulated by a periodic voltage. The device essentially comprises means for coupling and means for adding the amplitude-modulated sidebands so as to produce a signal for supplying antennas having a predetermined spectrum and to compensate for the couplings which exist between the antennas.

Abstract: A multi-channel rotary joint, designed to couple a stationary and a rotary component of a radar system to each other, comprises a main channel centered on the axis of rotation and a plurality of axially spaced ancillary channels coaxially surrounding the main channel. Each ancillary channel is formed by two capacitively coupled coplanar rings respectively carried on a stationary and on a rotatable dielectric sleeve centered on the axis, each ring comprising two concentric annular conductor strips on the inner and the outer sleeve surface. The inner and outer conductor strips of each ring are interrupted by small equispaced gaps which are relatively offset to form overlapping segments of two concentric transmission lines which are electrically continuous except at one point at which the line is coupled to a respective balun also formed by arcuate conductor strips.