Abstract: An antenna for transmitting rf energy. A polarizer for selectively polarizing the rf energy is operatively connected to a longitudinal shunt slotted plate for radiating rf energy therethrough. A rotational series slotted plate is operatively connected to the longitudinal shunt slotted plate for feeding the rf energy thereto. The plate has slots arranged in columns. First and second dual end slot array feeds are operatively connected to first and second columns of series slots of the rotational series slotted plate, said feeds having first and second input tee junctions. A manifold is operatively connected to the first and second input tee junctions for feeding the rf energy to first and second columns of the slots, the first and second columns of slots having, respectively, n1 and n2 numbers of slots with n1>n2. The manifold includes a power divider, and first and second waveguide lengths connected to the power divider for receiving rf energy.

Abstract: An antenna 10 with a dual end resonant slot array feed 26 improves the bandwidth performance of a resonant slotted waveguide planar array antenna 10. The dual end resonant slot array feed 26 includes a tee junction 28/30 which may be either an E-plane 28 or H-plane 30, two waveguide sections 32, 34, and two E-plane waveguide bends 36, 38. The two waveguide sections 32, 34 are formed by a septum 40 mounted in a slotted waveguide 42 for separating the input tee junction 38, 30 from the slots 44 of the slotted waveguide. The ends of the septum 40 coacting with the ends of the waveguide to form the E-plane waveguide beds 36, 38 . Thus, resonant feeding of the series-slot waveguides 50 is achieved by the opposing traveling waves thereby eliminating the need to use resonant short circuits, cavities, or folded short circuits.

Abstract: A microwave oscillator circuit having an antenna, wherein the effective reactive impedance of the oscillator circuit is altered by the movement of a reactive impedance changing element past the antenna to cause change of the oscillation condition of the oscillator. A change in oscillation condition is sensed and sent to a utilization device to determine speed and/or position. The utilization device can be a computer which receives a signal from a wheel speed determining system, wherefrom a signal is sent back to a braking system for the wheel to control braking thereof. This can be accomplished individually for each of the four wheels to provide an anti-locking braking system.

Abstract: An antenna with a dual end resonant slot array feed improves the bandwidth performance of a resonant slotted waveguide planar array antenna. The dual end resonant slot array feed includes a tee junction which may be either an E-plane or H-plane, two waveguide sections, and two E-plane waveguide bends. The two waveguide sections are formed by a septum mounted in a slotted waveguide for separating the input tee junction from the slots of the slotted waveguide. The ends of the septum coacting with the ends of the waveguide to form the E-plane waveguide bends. Thus, resonant feeding of the series-slot waveguides is achieved by the opposing traveling waves thereby eliminating the need to use resonant short circuits, cavities, or folded short circuits. Further direct coupling to the series slots directly adjacent to the E- or H-plane feed point is avoided by introducing the septum between the feed point and the row of slots.