Abstract: A method is disclosed in which the direction and range of sound generating targets (2) is determined solely by means of passive sensors (10, 11). In this connection it is proposed to employ a seismic sensor (10) in addition to the acoustic sensors (11) customarily required for a bearing angle determination. In this case, a line characteristic of the signal source of the target (2) is measured in the airborne sound spectrum as well as in the solid-borne sound spectrum and the radial target velocity (V.sub.z,r) is determined from the Doppler shift of these lines and the propagation velocity (C) of the corresponding waves and, under consideration of the bearing angle (.alpha.), the target range (r) is calculated therefrom.

Abstract: A system for remotely programming a mine includes a programming device comprising a computer having a data memory storing functions required to control the mine once laid, a code word memory and a random number generator. Stored data is displayed on an output device. A random number generator generates random numbers corresponding to respective addresses in data memory under which selected displayed functions are stored. The random numbers are stored as code words, together with corresponding data memory addresses, in the code word memory. A transmitter connected to the computer transmits the contents of the code word memory. A programmable electronic unit in the mine includes a receiver and a second computer. The second computer has a second code word memory for storing the transmitted code word memory, and a second data memory corresponding to the data memory of the programming device storing identical data.

Abstract: An arrangement for positioning a mine includes a mine housing and an inflatable, balloon mounted on a lateral exterior side of the mine housing. A gas generator is disposed in the mine housing and connected to the balloon for providing a supply of gas for inflating the balloon. A position sensor is disposed in the mine housing for monitoring the upright position of the mine housing and connected to the gas generator for controlling the supply of gas to the balloon in dependence of the upright position of the mine. A plurality of fixing nails are mounted in the bottom of the mine housing for fixing the position of the mine housing on the ground.

Abstract: An arrangement for programming the control of a mine including a pin (16) made of a material having a predeterminable magnetic permeability and inserted into a blind bore-like opening in a mine housing (12). Via a coil disposed in the interior of the mine and surroundng the blind bore-like opening, a resonant output frequency f.sub.R) of an oscillator, which frequency is a function of the permeability of the pin (16), is generated. If the detected resonant output frequency (f.sub.R) corresponds to a frequency (f.sub.i) stored in a frequency/address memory (42), an address (A.sub.i) associated with this frequency (f.sub.i) is read out and fed to a read-only memory (44). This determined address (A.sub.i) causes information (I.sub.i) associated with this address (A.sub.i) in the information memory (44) to be read out so that the action belonging to the respective information (I.sub.i) is initiated within the mine.