Expendable Active Decoy

Abstract

Method and system of electronic countermeasure comprising an airborne RF and IR decoy, being an independent, autonomous flying body that flies on its own, using its own aerodynamics, rotatable blades and fins, being applied as protection against Radio Frequency (RF) and infrared (IR) threats. Such an aircraft decoy comprises a body; a rotatable blade or vane disposed on the body; a power source capable of generating electrical current in response to rotation of the blade or vane; a wideband radar jammer responding to a radar signal with a wideband phantom radar signature corresponding to a phantom target; corner reflectors generating strong radar reflections corresponding to the phantom target; and an infrared source emitting a phantom infrared signature corresponding to a heat signature of the phantom target. Data stored within the decoy is destroyed automatically upon impact.

1 . An active decoy comprising:
 a deployable body;   at least one rotatable blade or vane disposed on the body;   a power generator disposed in the body and coupled to receive rotational torque from the at least one rotatable blade or vane, the power generator configured to generate electrical current in response to the rotational torque; and
 at least one of the following: 
 (a) a radar spoofing circuit disposed in the body, the radar spoofing circuit responding to a received radar signal with a phantom radar signature corresponding to a phantom target; 
 (b) corner RF reflectors disposed on the body, the corner reflectors generating strong radar reflections; and 
 (c) an infrared emitter disposed on the body, the infrared emitter emitting a phantom infrared signature corresponding to a heat signature of the phantom target. 
   
     
     
         2 . The active decoy of  claim 1  wherein the rotatable blade or vane is foldable into or onto the body. 
     
     
         3 . The active decoy of  claim 1  further including at least one angle-of-attack fin configured to at least in part counteract a rotational moment produced by the rotatable blade or vane. 
     
     
         4 . The active decoy of  claim 1  further including a variable electrical load selectively coupled to the power generator, and a circuit connected to control the variable electrical load to select a counter rotational torque the power generator applies to affect rotation of the body. 
     
     
         5 . The active decoy of  claim 1  wherein the body comprises a rectangular prism or cuboid dimensioned to be one inch by two inches by eight inches. 
     
     
         6 . The active decoy of  claim 1  wherein the infrared emitter comprises an array of infrared light emitting diodes disposed on at least one outer surface of the body. 
     
     
         7 . The active decoy of  claim 6  further including a controller connected to animate the array with a changing infrared light show emulating a heat signature of a phantom target. 
     
     
         8 . The active decoy of  claim 1  further including an inertial sensor that detects a ground strike and in response thereto, erases data stored within the body. 
     
     
         9 . The active decoy of  claim 1  wherein the radar spoofing circuit comprises at least one delay line that delays a received radar signal before retransmission. 
     
     
         10 . The active decoy of  claim 9  wherein the radar spoofing circuit further comprises a frequency shifter that frequency shifts the received radar signal to correspond to a negative doppler shift. 
     
     
         11 . The active decoy of  claim 1  wherein the corner RF reflectors return a radar signal with a radar cross section return signal close to that of a phantom target at low radar cross section. 
     
     
         12 . An active decoy comprising:
 a deployable housing;   at least one rotatable blade or vane disposed on the housing;   a power generator disposed in the housing and coupled to receive rotational torque from the at least one rotatable blade or vane, the power generator configured to generate electrical current in response to the rotational torque produced as the active decoy follows a ballistic trajectory through the air; and   a spoofing emitter disposed in or on the housing, the spoofing emitter emitting a spoofing signature of a phantom target.   
     
     
         13 . The active decoy of  claim 12  wherein the spoofing emitter comprises a radar spoofing circuit responding to a received radar signal with a phantom radar signature. 
     
     
         14 . The active decoy of  claim 12  wherein the spoofing emitter comprises corner RF reflectors disposed on the housing, the corner reflectors generating strong radar reflections. 
     
     
         15 . The active decoy of  claim 12  wherein the spoofing emitter comprises an infrared emitter disposed on the housing, the infrared emitter emitting a phantom infrared signature corresponding to a heat signature of the phantom target. 
     
     
         16 . The active decoy of  claim 12  wherein the housing comprises a cuboid dimensioned to fit into a conventional countermeasure magazine. 
     
     
         17 . The active decoy of  claim 12  further comprising at least one controller configured to self-destroy data stored in the housing upon detecting impact of the housing. 
     
     
         18 . The active decoy of  claim 12  further comprises a control circuit that selects a variable electrical load for the power generator to thereby control the rate of rotation of the housing. 
     
     
         19 . The active decoy of  claim 12  further including a charge storage device connected to the power generator and to an inductive charging interface. 
     
     
         20 . The active decoy of  claim 12  further including a navigation and communication device within the housing, the navigation and communication device configured to wirelessly communicate position and/or orientation information.