Angular Diversity Reception at 2290 MC Over a 188-Mile Path

Experiments were performed over the 188-mile Round Hill-Crawfords Hill path at 2290 mc to determine the feasibility of using angular diversity reception in a tropospheric scatter system. Using a 28-foot reflector, two beams were produced with two separate feed systems. The correlation of the signals received on one of the two beams with that received on the other was determined for various spacing of the beams, as well as for the azimuthal position of the antenna. These experiments show that angular diversity techniques can be effective depending on the proper choice of frequency, antenna size, and beam separation for paths in the neighborhood of 200 miles in length. A substantial "diversity gain" can be achieved even though partial correlation exists. These results also appear to be in good agreement with theoretical predictions for equal means and for the short periods of time applicable to obtaining reliable voice and high speed teletype communications.