초록 ▼

A method and apparatus for jamming radar and other electromagnetic signals is disclosed in which the jammer includes a single port, keyed primed oscillator which is primed with the low level signal received at its antenna. In one embodiment the priming signal is gradually shifted in frequency to int

A method and apparatus for jamming radar and other electromagnetic signals is disclosed in which the jammer includes a single port, keyed primed oscillator which is primed with the low level signal received at its antenna. In one embodiment the priming signal is gradually shifted in frequency to introduce a false doppler and is then injected into the tank circuit of the oscillator which is rapidly turned on and off (keyed) to produce a rapidly pulsed signal which tracks the frequency of the shifted priming signal. In this embodiment the oscillator keying unit is itself keyed to modulate the output signal of the oscillator to provide false bearing information. In another embodiment, the priming signal is injected directly into the tank circuit of the oscillator and the frequency of the output signal from the oscillator is varied to induce false doppler information. In both embodiments the pulsed signal from the oscillator is detected as a CW signal. The jammer also has a multiple threat capability in which simultaneously arriving signals from different sources result in a jammer output at each of the different frequencies of the incoming signals with sufficient jamming power at each frequency.

대표청구항 ▼

1. A jamming system adapted to be carried on board a target to provide an enemy radar with false information when the signal transmitted by said enemy radar is present at said target comprisinga primed oscillator including a circuit-which determines the natural oscillating frequency of the oscillato

1. A jamming system adapted to be carried on board a target to provide an enemy radar with false information when the signal transmitted by said enemy radar is present at said target comprisinga primed oscillator including a circuit-which determines the natural oscillating frequency of the oscillator an antenna coupled to said circuit for providing a priming signal from the signal transmitted from said enemy radar, and for radiating the jamming signal means for rapidly turning said oscillator on and off, and means for altering the frequency of the oscillator output signal in a predetermined manner to induce a doppler-like frequency shift.