Tracking antenna system

Claim 2

Tracking antenna system capable of detecting the direction and polarization of an incoming wave comprising: one aperture antenna; a circular waveguide connected to the antenna and exciting a dominant mode TE110 and higher modes having information as to the direction of the incoming wave therein; means for leading out a communication signal from the waveguide; distributed-coupling-type sampling coupler means including at least two pairs of coupling arms mounted on the waveguide for selectively leading out only a higher mode from the waveguide without affecting said dominant mode; a comparator network connected to the outputs of the two pairs of coupling arms of the sampling coupler means; and a signal processing circuit for detecting the direction of the incoming wave from the output of the comparator network.

Claim 3

Tracking antenna system as defined in claim 1, wherein each of said coupling arms is a rectangular waveguide, and the width a of the rectangular waveguide, the diameter D of the circular waveguide and the eigen-value x of the selectively led out higher mode are in the following relation 2a about D/x.

Claim 4

Tracking antenna system as defined in claim 1, wherein the selectively led out higher mode is TE210 mode.

Claim 5

Tracking antenna system as defined in claim 3, wherein two pairs of coupling arms are arranged at coordinate diametrical positions of the circular waveguide, one pair of coupling arms being electrostatically coupled to the circular waveguide, and the other pair of counter coupling arms being magnetically coupled to the circular waveguide.

Claim 6

Tracking antenna system as defined in claim 1, wherein the selectively led out higher mode is TM010 mode.

Claim 7

Tracking antenna system as defined in claim 1, wherein the aperture antenna and the circular waveguide are connected through a variable polarizer which can polarize the dominant TE110 mode and pass the higher modes without polarization.

Claim 8

Tracking antenna system as defined in claim 1, wherein the comparator network is composed of a circuit means capable of separating the selectively led out higher mode into a clockwise polariZed wave component and a counterclockwise polarized wave component.

Claim 9

Tracking antenna system as defined in claim 7, wherein the signal processing network comprises: a first input terminal to be provided with the separated clockwise polarized wave component signal from the comparator network; a second input terminal to be provided with the separated counterclockwise polarized wave component signal from the comparator network; and a hybrid circuit to which the signal at the first terminal is directly supplied and to which the signal at the second terminal is fed through first and second phase shifters so as to produce an output including information concerning the elevation angle of the incoming wave and another output serving as a control signal to be supplied to a servocontrol means; the amount of phase shift by the first phase shifter being controlled in an interlocked relation with the driving of the polarizer; and the amount of phase shift by the second phase shifter being controlled by the said another output of the hybrid circuit so that the said another output may become zero.