instrument by means of which information is obtained by the emission of electromagnetic waves and the reception of the waves after they have been reflected or re-radiated back towards the instrument, mõõtevahend, mille abil saadakse teavet elektromagnetlainete emissiooni ja lainete vastuvõtmise teel pärast nende peegeldumist või tagasikiirgust mõõtevahendi suunas, sensor which directly converts one type of energy into another, without an external source of energy or excitation to be required