Millimeter wave length guidance system

A high frequency target sensor system having search and track modes and having directive antenna means coupled to receiver means comprising:

• transmitter oscillator means coupled to said directive antenna means for illumination of targets and background by said directive antenna means, and further coupled to said receiver means for generating therein a beat frequency signal in the presence of said illuminated target or background;
• transmitter oscillator drive means having input terminals and output terminals, said output terminals being coupled to said transmitter oscillator for providing transmitter oscillator drive signals at said output terminals responsive to the amplitude of signals applied to said input terminals, the frequency of said transmitter oscillator signals being responsive to said transmitter oscillator drive signals;
• a plurality of range bin means coupled to receive said beat frequency signal, each of said range bins being responsive to illuminated objects in substantially contiguous predetermined ranges and for providing output signals from a bin corresponding to the range of said illuminated target, and for further providing signals from bins corresponding to ranges adjacent to said target range;
• difference means having input terminals coupled to receive said signals corresponding to ranges adjacent to said target, for providing in said tracking mode signals representative of the difference in amplitude of said adjacent range bin signals to said oscillator drive means;
• frequency discrimination means having input means coupled to receive said beat frequency signal and having an output means coupled to said transmitter oscillator drive means for providing in said tracking mode, background range tracking signals to said transmitter drive means upon departure of said beat frequency from a predetermined frequency value;
• range search generator means switchably coupled to said transmitter oscillator drive means for providing in said search mode range search signals;
• antenna drive means having input terminals and being coupled to said directive antenna means, for varying the position of said directive antenna means in space in response to signals applied to said antenna drive means input terminals;
• angle track demodulator means having input terminals coupled to receive said target range bin signal and output terminals, for providing signals K.epsilon..sub.e representative of the difference between said antenna's actual and desired line of sight rate of angular change with respect to a first predetermined reference in a first direction, and signals K.epsilon..sub.a representative of the difference between said antenna's actual and desired line of sight rate of angular change with respect to said first predetermined direction in a second direction orthogonal to said first direction, at said output terminals, said output terminals being coupled to said antenna drive means input terminals;
• and
• search command generator means coupled to said antenna drive means input terminal for providing search command signals .lambda..sub.del and .lambda..sub.daz, said directive antenna's motion in said first direction being responsive to said signal .lambda..sub.del and said directive antenna's motion in said second direction being responsive to said signal .lambda..sub.daz.

A high frequency, vehicle coupled, target detecting seeker system having twist reflector antenna means coupled to a receiver means comprising:

• transmitter oscillator means coupled to said directive antenna means for illumination of targets and background by said directive antenna means, and further coupled to said receiver means for generating therein a beat frequency signal in the presence of said illuminated target or background;
• transmitter oscillator drive means having input terminals and output terminals, said output terminals being coupled to said transmitter oscillator for providing transmitter oscillator drive signals at said output terminals responsive to the amplitude of signals applied to said input terminals, the frequency of said transmitter oscillator signals being responsive to said transmitter oscillator drive signals;
• a plurality of range bin means coupled to receive said beat frequency signal, each of said range bins being responsive to illuminated objects in substantially contiguous predetermined ranges and for providing output signals from a bin corresponding to the range of said illuminated target, and for further providing signals from bins correspondiing to ranges adjacent to said target range;
• difference means having input terminals coupled to receive said signals corresponding to ranges adjacent to said target, for providing in said tracking mode a signal representative of the difference in amplitude of said adjacent range bin signals to said oscillator drive means;
• frequency discrimination means having input means coupled to receive said beat frequency signal and having an output means coupled to said transmitter oscillator drive means for providing in said tracking mode, background range tracking signals to said transmitter drive means upon departure of said beat frequency from a predetermined frequency value;
• range search generator means switchably coupled to said transmitter oscillator drive means for providing in said search mode range search signals;
• antenna drive means having input terminals and being coupled to said directive antenna means, for varying the position of said directive antenna means in space in first and second directions, said first and second directions being orthogonal, in response to signals applied to saiid antenna drive means input terminals;
• angle track demodulator means having input terminals coupled to receive said target range bin signal and output terminals, for providing signals K.epsilon..sub.e representative of the difference between said antenna's actual and desired line of sight rate of angular change with respect to a first predetermined reference in said first direction, and signals K.epsilon..sub.a representative of the difference between said antenna's actual and desired line of sight rate of angular change with respect to said first predetermined direction in said second direction at said output terminals, said output terminals being coupled to said antenna drive means input terminals;
• search command generator means coupled to said antenna drive means input terminals for providing search command signals .lambda..sub.del and .lambda..sub.daz, said directive antenna's motion in said first direction being responsive to said signal .lambda..sub.del and said directive antenna's motion in said second direction being responsive to said signal .lambda..sub.daz ;
• first angle sensor means coupled to said antenna drive means for providing signals .beta. representative of said antenna drive means angle in said first direction with respect to said first predetermined reference;
• second angle sensor means coupled to said antenna drive means for providing signals .psi. representative of said antenna drive means angle in said second direction with respect to said first predetermined reference;
• first vehicle rate sensor means coupled to said vehicle for providing signals .theta..sub.p representative of the angular rate of change of said vehicle in a third direction with respect to a second predetermined reference;
• second vehicle rate sensor means coupled to said vehicle for providing .phi..sub.R representative of the angular rate of change of said vehicle in a fourth direction orthogonal to said third direction, with respect to said predetermined reference;
• third vehicle rate sensor means coupled to said vehicle for providing signals .phi..sub.y representative of the angular rate of change of said vehicle in a fifth direction orthogonal to said third and fourth directions, with respect to said second predetermined reference;
• and
• antenna control means coupled to said antenna drive means and adapted to receive said signals K.epsilon..sub.e, K.epsilon..sub.a, .theta..sub.p, .phi..sub.R, .theta..sub.y, .beta., .psi., .lambda..sub.del, and .lambda..sub.daz for providing signals in said tracking mode for controlling said antenna drive means rate of angualr change .beta. in said first direction substantially according to the formula:
• .beta.=1/2(K.epsilon..sub.e -.theta..sub.p +2.psi..theta..sub.R)
• and for further providing signals in said tracking mode for controlling said antenna drive means angular rate of change .psi. in said second direction substantially accordiing to the formula:
• .psi.=1/2(K.epsilon..sub.a -.theta..sub.y -2.beta..phi..sub.R)
• and for providing signals in said search mode for controlliing said antenna drive means angular rate of change .beta. in said first directiion substantially according to the formula:
• .beta.=1/2[K(-.intg.(.theta..sub.p -2.phi..sub.R .psi.)dt+.lambda..sub.del -2.beta.)-(.theta..sub.p -2.phi..sub.R .psi.)]
• and for further providing signals in said search mode for controlling said antenna drive means angular rate of change .psi. in said second direction substantially according to the formula:
• .psi.=1/2[K(-.intg.(.phi..sub.y+ 2.beta..phi..sub.R)dt+.lambda..sub.daz -2.psi.)-(.phi..sub.y+ 2.beta..phi..sub.R)].