摘要 |
FIELD: physics.SUBSTANCE: in order to use coherent accumulation when detecting parametric scatterers, a pair of short successive auxiliary radio pulses with identical shape and opposite phases is emitted simultaneously with pumping radio pulses at the sub-harmonic frequency of the pumping radio pulses. One of the radio pulses of the pair is a synchronising radio pulse and for this purpose, said pulse must be emitted in such a way that a pumping radio pulse is emitted over its duration. However, if during parametric excitation of the response signal in the parametric scatterer the phase of the synchronising signal differs by ?/2 from the phase of possible signals that can result from parametric generation, synchronisation will not take place. In order to avoid missing a target as a result of this phenomenon, emission of a sequence of radio pulses of the pumping signal in series that differ on phase by ? is proposed. If for one series of radio pulses of the pumping signal conditions are created where there will be no synchronisation, then for the next series synchronisation will definitely take place and coherent accumulation of the response signal in the receiver will be possible.EFFECT: avoiding missing a target due to lack of synchronisation.3 dwg |