HF propagation test of ISCAN

An experimental, 1.2 mile long working model of a short-wave receiving antenna with 14 fixed stacked "beams," named Inertialess Steerable Communication Antenna (ISCAN), is described briefly. The performance of the antenna under varying ionospheric propagation conditions was determined in preliminary tests which utilized HF pulses transmitted across the Atlantic. It is concluded that an ISCAN type antenna used in conjunction with electronic computer circuits for making a rapid choice of the beam affording a minimum number of simultaneously received propagation modes and, therefore, a minimum signal-element elongation, should make it possible at least to double the communication rates now available on most HF circuits operated well below MUF, or to reduce the error rate significantly. Marked interference reduction should sometimes be possible.