Refraction of radio waves in arbitrary atmosphere-ray-tracing picture

A development following Hartree, etc., is carried out of ray tracing using REAC differential analyzer. Ray families, on 2k-inch by 32-inch paper, are obtained for an atmosphere with a single n profile (index of refraction versus altitude curve), and for an atmosphere with three n profiles over the region of interest. The n profiles used were measured up to 10,000-foot altitude. The variation in radio field strength with separation between airplanes as measured in a recent air-to-air propagation flight is correlated with a variation or ray density based on index of refraction data taken during the flight. This was a flight which encountered a radio hole followed by its anti-hole (region of erulanced and interfering signals) within the geometrical horizon, and then a second hole and anti-hole at an anomalously large range beyond the horizon. The second anti-hole is accounted for by an anomalous-ranee layer near the ground and one in which the refractive gradient has a negative value nearly equal to l/(radius of earth}. In some respects the correlation is striking between ray-tracing picture and observed radio data.