AERIAL OBJECT DIRECTION FINDING METHOD Russian patent published in 2015 - IPC G01S3/00 

FIELD: radio engineering, communication.

SUBSTANCE: method includes receiving signals of an on-board transmitter using antennae which form an annular array, placed near and in parallel to the earth's surface; determining, from the signals received by the antennae of the array, the azimuth of the object; measuring complex amplitude values of the received signals and converting the measurements into an angular spectrum by multiplying with complex-conjugate antenna beam patterns; summing the multiplication results on the set of antennae and determining the square of the modulus of the sum. Signals are simultaneously received using additional antennae placed on the normal to the plane of the array from its centre. The angular spectrum is normalised on the sum of the squares of the moduli of the antenna beam patterns and the elevation angle of the object is determined as the position of its maximum. The antenna beam pattern is determined in the direction of the obtained azimuth and based on the coefficient of reflection of radio waves from the earth's surface.

EFFECT: improving accuracy of measuring the elevation angle by approximately an order with expansion of the region of reliable range-finding from 30 km to 70-80 km, which simplifies, improves reliability and safety of guiding aircraft on unequipped aerodromes and drilling sites.

6 dwg