I.V. Krjuchkov – Head of Department of the Research Institute RET, Bauman Moscow State Technical University. E–mail: email@example.com
V.V. Chapursky – Dr. Sc. (Eng.), Main Scientific Employee of Scientific Research Institute RET, Bauman Moscow State Technical University. E–mail: firstname.lastname@example.org
In spatial - multichannel radar systems such as MIMO Radar transmitting and receiving elements of sparse antenna system are each from another on the distances essentially greater then wave length. Thus phases of Doppler frequencies for each pair «transmitting element - receiving element » depend from bistatic delays of the target which for each pair of elements are a priori unknown. It results in impossibility of coherent accumulation of Doppler spectra on all pairs «transmitting element - receiving element». Accessible in this case is non coherent accumulation of the spectra modules, bringing to losses of the signal to noise ratio. Such approach corresponds to a principle of Doppler processing priority accepted earlier in spatial - multichannel radars. In interests of exception of non coherent accumulation losses the urgency of research a completely coherent accumulation methods in multifrequency spatially multichannel radars is kept.
In connection with above stated the variants of space-time signals processing in spatially multichannel radar systems with preliminary gating on a delay of multifrequency pulses of a pulse packet on receiving channels outputs of receiving array are synthesized in the article. Three variants of algorithms and block diagrams are received: 1) on the basis of Doppler processing priority with non coherent accumulation of spectra, measuring of target Doppler frequencies and the subsequent focusing on spatial coordinates (range, an azimuth and elevation); 2) on the basis of Doppler processing priority with the subsequent completely coherent processing bringing to multichannel phasing of spectra on angular coordinates and range; 3) on the basis of a time processing priority with phasing complex amplitudes of receiving channels on angular coordinates and range with the subsequent Doppler processing on everyone frequency component and association of results on all transmitted frequencies and receiving elements. The possibility of focusing on a target azimuth and range is confirmed with the example of modeling at the first processing variant.