Abstract An antenna system adapted to operate over relatively wide scan angles is disclosed. The antenna system includes a means for providing a control signal indicative of the relationship between a desired beam deflection angle and a predetermined beam deflection angle, and means, responsive to the control signal, for causing the antenna to operate in the TE11 mode when the desired beam deflection angle is less than the predetermined beam deflection angle thereby to generate a broadside antenna radiation pattern, or the TM01 mode when the desired beam deflection angle is greater than or equal to the predetermined beam deflection angle thereby to generate an end fire antenna radiation pattern. The latter means includes a power divider having a pair of output ports, phase shifter means for providing either O* or 180* phase shift between the energy passing through such pair of output ports selectively in accordance with the control signal, and a radiating aperture section including a circular waveguide coupled to the pair of output ports and dimensioned to support either the TE11 mode or the TM01 mode. When such phase shift is 0* the antenna operates in the TE11 mode and when such phase shift is 180* the antenna operates in the TM11 mode.
An antenna system, comprising: a. means for providing a control signal indicative of the relationship between a desired beam deflection angle and a predetermined beam deflection angle; and b. means, responsive to the control signal, for causing the antenna to operate in a selected one of a plurality of possible operating modes, such mode being selected in accordance with the relationship between the desired beam deflection angle and the predetermined beam deflection angle including means for causing one mode of such plurality of possible operating modes to produce a broadside antenna radiation pattern and another one of such modes to produce an end fire antenna radiation pattern.
Claim 2
Dependent Claim
107 words
An antenna system, comprising: a. means for providing a control signal indicative of the relationship between a desired beam deflection angle and a predetermined beam deflection angle; and b. means, responsive to the control signal, for causing the antenna to operate in a selected one of a plurality of possible operating modes, such mode being selected in accordance with the relationship between the desired beam deflection angle and the predetermined beam deflection angle including means for causing one mode of such plurality of possible operating modes to produce a broadside antenna radiation pattern and another one of such modes to produce an end fire antenna radiation pattern.
Claim 3
Dependent Claim
36 words
The antenna system recited in claim 1 wherein the operating mode producing the broadside antenna radiation pattern is the TE11 mode and the operating mode producing the end fire antenna radiation pattern is the TM01 mode.
Claim 4
Dependent Claim
101 words
The antenna system recited in claim 1 wherein the control signal responding means includes: a. a power divider having a pair of output ports; b. means, responsive to the control signal, for providing either a 0* or 180* phase shift between the radio frequency energy passing through the pair of output ports selectively in response to the control signal; and c. a radiating aperture section including a circular waveguide coupled to the output ports, such waveguide being dimensioned with a cutoff frequency lower than that of either the TE11 mode or the TM01 mode of the radio frequency energy propagating therethrough.
Claim 5
Dependent Claim
28 words
The antenna system recited in claim 3 wherein the power divider is dimensioned to divide the radio frequency energy passing therethrough Equally between the pair of output ports.