The AN/AST-4(V) (AST-4) Radar Emission Simulating Set (RESS) is a pod mounted, airborne, multimode, radar emitter designed to present effective simulations of hostile antiship missile threats. The system consists of one or more simulator assemblies (pods), a generator-control-indicator (CI) and interfacing cable assemblies. It is designed and configured for operational simplicity and high efficiency when installed in an aircraft. The pod may be either wing or fuselage mounted on subsonic aircraft. The pod is controlled by the cockpit mounted CI to provide real-time control during flight. The three different versions (variants) of the AST-4 are the result of selection and installation of various magnetrons, with compatible waveguides and antennae which provide emissions in the H, I, or J frequency bands at various power levels.The generator-control-indicator (CI) provides the switches and circuitry required for inflight remote control of the AST-4 off, standby, and radiate modes, and PRF modes and parameters. The control box circuitry provides a PRF to the radar transmitting set modulator that overrides the internal PRF generator. In the SCAN modes, the PRF applied to the modulator is turned on and off at selected time intervals to simulate the low power of the back lobes of a scanning antenna during the off-target period. Indicator lights are provided to indicate radar transmitting set ready and radiate modes of operation and scan fault conditions. An indicator light is provided to indicate 28 VDC is being generated in the system.
Multi-mode transmissions are controlled remotely from the aircraft cockpit, by inflight selection of off, standby, radiate modes, pulse repetition frequency modes and parameters, and scan modes and parameters using the AST-4 control indicator.
Threat simulation is accomplished by producing the same radio frequency (RF), RF pulse repetition frequency (PRF), and RF pulse widths (PW) as the designated threat. The scan of the designated threat is simulated by turning the RF transmissions on and off at specific intervals. Parameter control flexibility was incorporated in the pod to permit parameter changes in PRF, PW, and RF amplitude modulation during a mission. In flight parameter changes permit the use of a single transmitter to produce time-sequenced threat signals. Threat simulations are created using the on board AN/DPT-1 Radar Transmitting Set fitted with one of the three magnetron assemblies to provide RF control.
AST-4(V) Radar Emissions Simulating Set