Abstract: For less expensive estimation the impulse response x.sub.MOS of a high-resolution, band-limited radar channel in a radar station operating with an expanded transmitted pulse a(t), from a received signal e, over which a correlated or uncorrelated additive interference signal n can be superimposed, with the use of knowledge about the spread code c and the use of a channel estimator with which a so-called linear, optimum unbiased estimation of the radar channel impulse response x.sub.MOS is performed in a time range covering M range gates of interest, the linear, optimum estimation in the unbiased channel estimator is modified in such a way that the pulse response x.sub.MOS of the band-limited radar channel is determined according to the basic principle of a multiplication of the sampled received signal e and an inverse estimation matrix A.sub.E.sup.-1. The matrix A.sub.E is formed by the extension of the rectangular matrix represented by the components c.sub.

Abstract: A phase regulating circuit operating in accordance with the delay lock loop principle DLL for synchronizing the phase of a pseudo-random generator at the receiving end which is controlled by a pulse train oscillator and having two identical signal channels and wherein the inputs to the signal channels from the pseudo-random generator is rapidly switched between the two input mixers and wherein the output of the mixing networks is rapidly switched to a difference forming device so as to provide an output for the frequency control circuit of the pseudo-random generator.