Adaptive antenna system employing FM receiver

In an adaptive array system having first and second input terminals for connection to separate spaced apart antennas;

• the improvement comprising first and second input circuits, frequency discriminator means, commutation means selectively coupling said first and second input circuits to said discriminator means, synchronous rectifying means synchronized with said commutation means and coupled to the output of said discriminator means, variable control means coupled to said input terminals, means for converting amplitude variations to phase variations for coupling said variable signal control means to said input circuits, and means controlling said variable control means with the output of said synchronous rectifying means, said variable control means comprising variable attenuator means, said converting means comprising quadrature hybrid means.

In an adaptive array system having first and second input terminals for connection to separate spaced apart antennas;

• the improvement comprising first and second input circuits, frequency discriminator means, commutation means selectively coupling said first and second input circuits to said discriminator means, synchronous rectifying means synchronized with said commutation means and coupled to the output of said discriminator means, variable control means coupled to said input terminals, means for converting amplitude variations to phase variations for coupling said variable control means to said input circuits, and means controlling said variable control means with the output of said synchronous rectifying means, said control means comprising separate phase shifting and attenuation control means, time sharing switching means coupled to apply input signals to said first and second input circuits, first means coupling the output of said phase shifting means to said time sharing means, and second means coupling the output of said attenuator means to said time sharing means, said second means comprising means for converting amplitude variations to phase variations.

In an adaptive array system having first and second input terminals for connection to separate spaced apart antennas;

• the improvement comprising first and second input circuits, frequency discriminator means, commutation means selectively coupling said first and second input circuits to said discriminator means, synchronous rectifying means synchronized with said commutation means and coupled to the output of said discriminator means, sum-difference hybrid means having its sum and difference outputs coupled to said first and second input circuits respectively, means including control means coupling said first and second input terminals to the input of said hybrid, means controlling said control means with the output of said synchronous rectifying means, and comprising time sharing means for selectively coupling the output of said control means and the outputs of said hybrid to said first and second input circuits.

In an adaptive array system having first and second input for connection to separate spaced apart antennas;

• the improvement comprising first and second input circuits, frequency discriminator means, commutation means selectively coupling said first and second input circuits to said discriminator means, synchronous rectifying means synchronized with said commutation means and coupled to the output of said discriminator means, sum-difference hybrid means having its sum and difference outputs coupled to said first and second input circuits respectively, means including control means coupling said first and second input terminals to the input of said hybrid, means controlling said control means with the output of said synchronous rectifying means, said control means comprising variable attenuation means and variable phase shifting means, and further comprising a phase shifter coupled between one of the outputs of said hybrid and the respective input circuit, compensator means selectively connectable to bypass said phase shifter, and further comprising additional compensator means coupling the other output of said hybrid to the respective input dircuit, and time sharing control means for enabling separate control of said attenuation and phase shifting means.

In an adaptive antenna array system having first and second input terminals for connection to separate spaced apart antennas;

• the improvement comprising first and second input circuits, frequency discriminator means, commutation means selectively coupling said first and second input circuits to said discriminator means, synchronous rectifying means synchronized with said commutation means and coupled to the output of said discriminator means, sum-difference hybrid means, variable phase shifting means and variable attenuation means coupling said first and second input terminals to the inputs of said sum-difference hybrid, fixed phase shift means connected to couple one output of said hybrid to said first input circuits, means coupling the other output of said hybrid to said second input circuit, first commutation means connected to control the insertion of said phase shifter, second and third commutation means connected to selectively control said variable phase shifting means variable attenuator means with the output of said rectifying means, and programmed circuit means for selectively controlling said first, second and third commutation means.