RADIO MONITORING STATION Russian patent published in 2012 - IPC H04K3/00 

FIELD: radio engineering.

SUBSTANCE: radio monitoring station has an antenna device, a receiver, a direction finder, a received signal parameter analyser, a device for storing and processing the obtained information and a telemetering device, three receiving antennae, an adjustment unit, two heterodynes, four mixers, three first intermediate frequency amplifiers, a detector, three delay lines, a switch, a second intermediate frequency amplifier, five multipliers, three narrow-band filters, a phase detector, two phase meters, two 90° phase changers, two low-pass filters, two squaring devices, an adder and a threshold unit, connected to each other in a certain manner.

EFFECT: high reliability of detecting composite signals with unknown carrier frequency, given tolerance range and random initial phase by quadrature signal processing.