Abstract: A diplexer (14) has a first rectangular waveguide (38) extending from a front port (16) to a back wall (70), the back wall having a rectangular opening (72) therein constituting a section of a second rectangular waveguide (20) and serving as a back port (18) of the diplexer. A first spectral region of electromagnetic power communicates between the front port and a side port (28), and a second spectral region of electromagnetic power communicates between the front port and the back port. A center frequency of the second spectral region is greater than a center frequency of the first spectral region by a factor greater than or equal approximately to two. The side port includes an aperture (126) disposed in a sidewall (42) of the first waveguide, a third waveguide (32), and a coupling element (128) extending from the third waveguide through the aperture into the first waveguide for coupling electromagnetic power at the first spectral region between the first and the third waveguides.

Abstract: A diplexer for processing polarized energy at separate transmit and receive frequencies. The nature of the polarization may be circular, linear or elliptical depending upon the phasing associated therewith. The diplexer comprises a waveguide having first and second ports disposed at opposite ends thereof. A symmetrical bandpass resonator arrangement is disposed around the periphery of the waveguide and couples energy at the receive frequency out of the waveguide. A symmetrical bandstop resonator arrangement is also disposed around the periphery of the waveguide and filters energy at the receive frequency to prevent coupling of received energy to the second port. The bandpass resonators of each of the resonator arrangements generally include tuning members that control the amount of energy coupled from the waveguide and that adjust and balance the polarization components of the energy to maintain the polarization state thereof.

Abstract: A feed horn employing a novel compensator design which substantially reduces off-axis cross polarized components of circularly polarized energy over a wide range of angular directions. The compensator comprises a plurality of L-shaped compensating conductors disposed in a generally symmetrical fashion about a longitudinal axis of the feed horn. The conductors extend inwardly from the output aperture of the feed horn and then radially outwards a predetermined distance away from the axis toward the horn sidewall. The conductors are disposed at an angle relative to the axis, which angle is generally defined by an cone whose apex is the same as the apex of the feed horn. A nonconducting support structure supports the conductors within the feed horn. A dielectric matching member is disposed in the feed horn to eliminate unwanted energy reflections.

Abstract: A wideband microwave diplexer is provided which includes a waveguide section characterized by a longitudinal dimension, and defining first and second longitudinally spaced ports, for propagating microwave power substantially within a first lower frequency band between said first port and said second port; coupling resonator means for coupling microwave power substantially within a second higher frequency band between said waveguide section and a coaxial transmission line; and band stop filter means for substantially preventing microwave power substantially within the second frequency band from propagating to said second port.

Abstract: A modulator system for converting a three-channel input microwave signal to a single-channel output microwave signal is formed of two microwave sections which are joined together at both their inputs and their outputs by hybrid circuits, one of which serves as a power divider and the other which serves as a power combiner. Each of the microwave sections includes a pair of couplers which are joined by a Faraday rotator. First and second microwave input signals are applied to a first port of an input coupler in each of these sections. A third microwave signal is connected by the hybrid divider to a second input port in the input couplers of each of the microwave sections. Polarization of the third signal is vertical and is maintained through the two sections. Polarization of the first and second signals is horizontal and is maintained through the two sections.