Radio direction finding method based on the Poynting vector measurement using a vector antenna

Phase interferometry and correlation-interferometric methods, which are widely used at present for direction finding, have one common drawback. In the presence of scatterers in the immediate vicinity of the antenna array, the distortion of the spatial phase pattern leads to the appearance of significant direction finding errors. This situation is typical when placing a direction finder both in stationary conditions (the presence of a supporting metal mast, lightning rods, etc.), and when placed on mobile carriers (cars, aircrafts, etc.). Also, when placed on the carrier, the issue of the operating frequency band is acute, since the size of the carrier can significantly limit the base of the direction finder.

The article analyzes the radio direction finding method based on the measurement of all projections of the electric and magnetic field strength vectors in a number of points in space using a vector antenna. A comparison has been made with the correlation-interferometric direction finding method. The advantage of the method is the possibility of measuring the azimuth and elevation angle of the radio source by measuring the field at a single point in space, which is especially important when placing a direction finder on a UAV. By modeling, it has been found out that in the long-wavelength region of scattering of waves at an object, the proposed method of direction finding can give more accurate results of measuring the elevation angle of the radio source than the correlation-interference method of direction finding.