Abstract: Methods and apparatus for a coincident phase center dual polarized slotline radiator. In one embodiment, a radiator includes, for each of two polarizations in a unit cell: first and second fins to provide an air transition for a signal, the radiator including a throat region between the first and second fins, a microstrip path transitioning to a slotline feed, a slotline split forming a part of the slotline feed to provide signal power division and 180 degree phase shift for rejoinder in the throat of the radiator to launch the signal into free space. In another embodiment, a four port radiator is provided.

Abstract: Methods and apparatus for a coincident phase center dual polarized slotline radiator. In one embodiment, a radiator includes, for each of two polarizations in a unit cell: first and second fins to provide an air transition for a signal, the radiator including a throat region between the first and second fins, a microstrip path transitioning to a slotline feed, a slotline split forming a part of the slotline feed to provide signal power division and 180 degree phase shift for rejoinder in the throat of the radiator to launch the signal into free space. In another embodiment, a four port radiator is provided.

Abstract: A radio frequency (RF) channelizer includes a first four-port balun, a second four part balun and a pair of filters coupled between the first and second four port baluns. The filters operate such that RF signals having a frequency within a desired frequency band (so-called “in-band” signals) can propagate between the first and second baluns (e.g. from the first balun to the second balun) while signals having a frequency outside the desired frequency band (so-called “out-of-band signals”) are reflected back to the first balun. One filter reflects out-of-band signals while maintaining the magnitude and phase of the signal (i.e. with a 0 degree phase shift), while the other filter reflects out-of-band signals with a phase-reversal (i.e. with a 180 degree phase shift). With this approach, the reflected signals propagate to a sum port (or even mode port) of the first balun. In this way, the balun-filter combination results in a channelizer which separates signals into different frequency bands.

Abstract: A radio frequency (RF) channelizer includes a first four-port balun, a second four part balun and a pair of filters coupled between the first and second four port baluns. The filters operate such that RF signals having a frequency within a desired frequency band (so-called “in-band” signals) can propagate between the first and second baluns (e.g. from the first balun to the second balun) while signals having a frequency outside the desired frequency band (so-called “out-of-band signals”) are reflected back to the first balun. One filter reflects out-of-band signals while maintaining the magnitude and phase of the signal (i.e. with a 0 degree phase shift), while the other filter reflects out-of-band signals with a phase-reversal (i.e. with a 180 degree phase shift). With this approach, the reflected signals propagate to a sum port (or even mode port) of the first balun. In this way, the balun-filter combination results in a channelizer which separates signals into different frequency bands.

Abstract: A radiator element includes a pair of substrates each having a transition section and a feed surface, each of the substrates is spaced apart from one another. The radiator element further includes a balanced symmetrical feed having a pair of radio frequency (RF) feed lines disposed adjacent to and electromagnetically coupled to the feed surface of one of a corresponding one of the pair of transition sections, and the pair of radio frequency feed lines forms a signal null point adjacent the transition sections.