Angle and Doppler Measurements of Microwaves Propagated Beyond the Horizon
Department of Electrical Engineering, Stanford University, 1971 - Shortwave radio - 145 pages
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).
What people are saying - Write a review
We haven't found any reviews in the usual places.
Figure Page 1 Map of propagation path and surrounding area 5
Profile of propagation path
36 other sections not shown
15 FREQUENCY Hz 26 June 98 99 PROBABILITY 99 PROBABILITY SIGNAL AMPLIFIER amplitude and phase amplitude distributions angular-response patterns antenna angular-response patterns antenna array antenna scans array signal atmosphere Attn bandpass filter bandwidth beam-pointing angle block diagram broadening BUFFER AMPLIFIER calibration Center Commanding General U.S. Commanding Officer CONTINUED data sets data-gathering array DECtape doppler measurements doppler spectra ELEVATION ANGLE degrees evaluated EXCEED GIVEN LEVEL fading rate frequency offset frequency spectrum GIVEN LEVEL percent incoherent scattering klystron lobe lowpass filtered mainlobe meteorological profiles microwave Non-Rayleigh Officer U.S. output probe propagation path Radio Radiosonde Rayleigh distributed received signal recorded refractive-index refractivity field response patterns reveal sampled signal shown in Figs SIGNAL WILL EXCEED single antenna element source regions spatial specular component specular reflection steady-signal component tape temperature inversion tenna tion transhorizon signal transmitter Tropospheric turbulence U.S. Army vertical Wheelon wind field