Radar device, from which digitally coded pulses are emitted

摘要

The radio device emits relatively long pulses, which are in each case modulated according to a certain code with a first or a second phase value. On the reception side, a pulse compression takes place in the evaluation. The known technique, in which tuned filters are used, is modified in such a way that a plurality of signal processing channels (318, 319, 320; 315, 316; 321, 322, 323) are provided for the pulse compression. If three channels are provided, in one channel (315, 316) a pulse compression takes place in a known way by means of tuned filters. In the two other signal processing channels, signals are processed with great positive or negative Doppler shifts. The sharply delimited complex video signal (301, 302, 303) generated in the receiver is fed to two shift registers (305, 306), which are respectively assigned to the first part and to the remaining part of the received code. In the signal processing channels for positive and negative Doppler shifts, complex multiplications (318, 321) are carried out, to be precise with a calculated phase rotation factor, which is optimised for a particular positive or negative Doppler shift. Instead of the three signal processing channels mentioned, it is also possible for more signal processing channels to be provided. In addition, it is possible to divide the received code into more than two part-codes. <IMAGE>