Abstract: A personal direction finding apparatus for determining the direction to be followed in order to reach a predetermined spot which includes a headset provided with two earphones and a circuit for generating a track error signal. The circuit includes a compass supported on the headset for outputting a heading signal corresponding to the heading of the direction of travel, a receiver for a position location and navigation system outputting a signal for the heading to be followed via one output, and a track error computing circuit.

Abstract: A personal direction finding apparatus for sensing electromagnetic, infrared or ultrasound radiation from a source (S) to determine the direction of the source or generate a virtual sound environment. The apparatus is characterized in that it comprises a radiation sensing device (1) worn on the user's head (2) for generating a signal having a variable characteristic depending on the direction (R) of the source (S) relative to the sensing device (1), i.e. the position of the user's head, a receiver (4) optionally provided as a demodulator, a direction signal processing circuit (5) outputting a control signal (x) indicating the angular deviation (a) between the direction of the source (S) and the current position of the sensing device (1), i.e. the user's viewing axis, and two earphones (3d, 3g) placed over the user's ears and connected to the output of the processing circuit (5).

Abstract: Radiodirection finding method and apparatus using Doppler effect frequency modulation for measuring the bearing of a source transmitting a high frequency signal, wherein either on the reception side or on the transmission side, several antenna strands are used in pairs diametrically spaced from each other and spaced evenly apart angularly about a circumference. A first pair of diametrically spaced antenna strands are energized and then the next pair of diametrically spaced antenna strands in turn are selectively energized so as to create, at all times, a mobile fictitious antenna moving diametrically and alternately between the two diametrically opposite antenna strands of the particular pair of antenna strands considered. Different pairs of diametrically opposite antenna strands are successively energized in an angularly rotating sequence from the first pair of antenna strands.