Parabolic antennas as components of communications transmitting systems. II

Parabolic antennas are used to transmit or send microwaves in the dm, cm, or mm range, and must therefore have a high reflector quality and good dynamic behavior. The essential construction principles of several new parabolic antenna designs are outlined, and the application of these antennas to commercial communications systems is discussed. In particular, the German Experimental Ship antenna is described; this antenna consists of 72 individual reflectors on a circular surface, 1.5 m in diameter. A highly-exact millimeter wavelength 25 m radio-telescope has been developed by American scientists, and a 30 m radio-telescope, the reflector surface of which consists of 420 sandwiched panels, is being designed by German and French engineers. The collinear and Christiansen interferometer antenna systems and the Dutch synthesis radio-telescope are also discussed.