the antenna 3 and the launching device 1 are arranged in a suitable known way to be able to be turned vertically and horizontally the launchable body is designated 4 and its rear part is provided with a receiver antenna 5 the antenna 5 is a so called electrically controlled antenna and is constructed in the rear end of the launchable body 4 the antenna can advantageously consist of antenna slots milled out of metal a so called slot antenna in which the metal can at the same time form part of the casing of the launchable body by this means the launchable body is given a strong rear end the electronic components are small and light and thus resistant to g forces the arrangement and in particular the antennas are designed preferably for the millimeter wave range and for example to work within the frequency range 35 45 ghz the advantage of this frequency range is that the antenna can be made very small as the dipoles incorporated in it are only a few millimeters long this frequency range also functions well in various kinds of weather conditions in the embodiment shown the beam of the antenna 3 designated by 6 sweeps horizontally with a suitable sweep angle from for.