Book Description

The report presents results of angle and doppler measurements of the specular and scattered components of transhorizon signals. The transhorizon signal measurement are recorded on a vertical 12-element data-gathering array and receiving system. The array measures the relative phase and amplitude along the wavefront of an S-band CW signal transmitted from a source 164 km (102 miles) away--sell beyond the horizon. The data are processed to obtain the amplitude distributions, averaged array angular-response patterns, and doppler spectra. In addition, the radio data are supplemented with airborne refractivity and temperature--profile measurements. Two unique features of this work are described. First, the doppler frequency spectrum of the received signal is evaluated from the sampled amplitude and phase information, and second, the amplitude distributions and doppler spectra are evaluated for the received signal at a single antenna element or for a conventional broadside array. Consequently, the distributions and spectra are available as a function of the array beam-pointing angle. (Author).