Experiments with directivity steering for fading reduction

Short-wave fading is largely due to phase interference between multiple path signals of varying path length. Fortunately, stable angular differences usually exist between these paths at the point of reception. It is therefore desirable to employ antenna directivity which is “steerable” and sufficiently sharp to accept only one of the several paths in order to reduce this fading. This paper describes experiments made with a “steerable” directive antenna during reception of transoceanic short-wave signals. The results demonstrate that sharp angular discrimination is a basically sound method of combating fading which is due to phase interference.