Information technologies have many current and future applications dealing with signals transmission to antennas and antenna systems which are removed from each other in space, but have to be fed by in-phase analog signals or digital signals without mutual delays.

In fact big antenna arrays, radiointerferometers with long base line, multipositional radars, systems of hydroacoustical and seismological monitoring, geo-logical systems of row materials search and mobile communication systems realize holographic principles of signals transmission and especially of signal registration and processing, which demand correct knowledge of both phase (time delay for digital signals) and amplitude distributions of electromagnetic and acoustic fields.

For this purpose removed in space antenna elements, separate antennas, radiotelescopes, acoustical sensors may be united by phase stabilized fiber links, providing phase difference at their outputs, which should not exceed 1…5 degrees. These kinds of transmission links are known as phase stabilized links (PSL). The problem of phase stability tradition-ally resolved by two principal methods. Component approach: manufacturing the transmission links with given phase stability properties; system approach: usage the feedback systems with controllable phase shifters (delay lines) for parasitic phase difference (delays) compensation. Both methods have obvious disadvantages due to technological complexity and bad mass–weight–cost characteristics of the integral system.