Abstract: Antenna apparatus for changing the antenna radiation pattern includes a transmitter and first and second antenna members. Each antenna member has a plurality of antenna elements which are arranged such that the elements of each antenna member are exponentially amplitude fed. A directional coupler responsive to the transmitter divides the power from the transmitter between the first and second antenna members such that each antenna member is provided with a signal of equal amplitude and phase. A variable phase shifter connected between the directional coupler and one of the antenna members is selectively operable either at 0.degree., or at a predetermined value in the range of about 60.degree. to 120.degree.. A symmetrical pencil beam pattern is provided when the variable phase shifter is set at 0.degree., and a cosecant squared pattern is provided when the variable phase shifter is set at a value in the range of about 60.degree. to 120.degree..

Abstract: An apparatus and method for use in an n-element electronically scannable array antenna provides a notched auxillary radiation pattern for use in reducing interference energy received in the sidelobes of the antenna's main radiation pattern. The apparatus includes circuitry for feeding the antenna elements in series from one end of the array to the opposed end thereof. Each antenna element is fed through a directional coupler which is responsive to its associated antenna element along with the downstream antenna elements in the array. The directional couplers provide a first output signal for forming a primary radiation pattern. At least one directional coupler also provides a second output signal on receive for forming an auxiliary radiation pattern having a notch in the direction of the primary radiation pattern main beam and electronically steerable therewith, and a relatively uniform response in all other directions.

Abstract: High levels of R.F. power are controlled and switched by means of a hybrid switching network that employs an intermediate power level switch matrix in conjunction with a pair of 8.34 (nominal) directional couplers and a phasing network. The two directional couplers are connected in tandem by two equal length transmission lines to form a broadband quadrature 3dB hybrid. Switching is accomplished by selectively inserting a 180.degree. phase shift means into the lower power carrying transmission line. The phase shifting means can be a length of transmission line, a solid state device, or a Schiffman type phase shifter.