DIRECTION FINDER Russian patent published in 1998 - IPC

FIELD: radio beacon navigation systems. SUBSTANCE: proposed direction finder has antenna with two outputs, each one connected through logarithmic receiver to proper input of first subtracter. Antenna has three identical direction patterns, two of them being turned away in symmetry with reference to center direction pattern by adjustable value of angular separation. Antenna has input controlling angular separation and third output. In addition there are inserted logarithmic receiver connected to third output of antenna, second subtracter which inputs are connected to outputs of second and third logarithmic receivers, adder and third subtracter which inputs are connected to outputs of first and second subtracter, three dividers, multiplier, delay unit and indicator connected to output of first divider. Output of third subtracter is connected to input of second divider which output is connected to inputs of first and third dividers. Input of antenna controlling angular separation is connected to output of multiplier and to input of delay unit, output of the latter is connected to second inputs of second and third dividers. Output of third divider is connected to input of multiplier which second input is input of stabilized value of direction finding sensitivity which is established on basis of these or other tactical- technical requirements to direction finder. EFFECT: increased accuracy of direction finding due to correction of a priory uncertainty in direction finding sensitivity, its stabilization at specified level by adaptive retuning of angular separation of directional pattern, possibility of programmable control over direction finding sensitivity within range of variations of propagation of radio waves in scattering media, frequency independence signifying lack of necessity of measurement of frequency of received signal. 2 dwg