Transponder for use in locating avalanche victims

A transponder to be carried on the body of a person for use in locating avalanche victims, which transponder is designed for cooperation with a search-transmitter which generates a signal with a fundamental frequency of approximately 1000 MHz, said transponder comprising a receiver having a passive non-linear element which produces a higher harmonic by distortion of the fundamental frequency received from the search transmitter;

• metal parts connected to the non-linear element and which function as a receiver/transmitter antenna tuned to the frequency employed;
• and a dielectric layer covering a side of the transponder facing the body, the thickness of the layer being substantially adapted for use with the fundamental and a reradiated harmonic frequency and to the dielectric constant of the layer, the size of the antenna being substantially adapted for use with said dielectric constant.