In accordance with this diagram, the task of space selection of radio emission sources by the multi-channel receive-measurement direction finding complex is divided into three portions:
- forming sample of amplitude-phase distribution vectors of received signals at antenna array elements;
- processing the formed sample in order to determine directions to emission sources and to choose a "useful" signal from a "signal plus noise" mixture;
- registering "useful" signal for its further processing.
Measurement of amplitude-phase distribution of electromagnetic field at antenna array elements is carried out by multi-channel receiver apparatus forming signal quadrature components received by each of elements in analog form. Control of receiver apparatus in performed in on-line mode in accordance with the information produced by received signal analysis device. Conversion of signal quadrature components into the digital form is performed by analog-to-digital converters included into the analysis device structure. Identity and stability of individual channels of receiver apparatus during its operation in ensured by automatic parameter adjustment in accordance to special control signals which forming is also performed in the analysis device.
Processing of digitized sample of received signal quadrature components for direction finding of emission sources and for suppression of signals from noise sources is performed in a space selection unit which functioning is performed in accordance with the MUSIC (MUltiple SIgnal Classification) algorithm. The basis of this algorithm is in decomposition of M-dimensional space of measurements into a direct sum of two orthogonal subspaces: the signal subspace and the noise subspace.
The MUSIC algorithm ensures a super-resolution of emission sources relative to the matched angle resolution of antenna, which is defined by inverse value from number of wavelength comprised in the projection of antenna size into the plane perpendicular to the signal arrival direction.
Recording of "useful" signal to the magnetic medium for the further processing of this signal is carried out by a registering device.
For the purpose of geodetic connection of direction finding complex produced in a moveable embodiment, the apparatus of user of satellite radio navigation system "GLONASS" should be included into the structure of this complex.