Transmission of Circular Polarized Waves Between Elevated Antenna

Transmission of circularly polarized signals between elevated antenna over lossy earth is discussed for a frequency of 100 MHz. By decomposing the circularly polarized signals into vertical and horizontal components and considering only direct and ground-reflected waves, it is shown that for fixed transmitting antenna height and horizontal separation, the field intensity at the receiving antenna varies sinusoidally with receiving antenna height. Reference curves of field strength versus height are included for typical tower heights, separations, and soil conditions. Comments on FCC power height curves are also included.