Abstract: A radio frequency switch disposed over a substrate having ground plane conductors disposed over an opposite surface thereof is described. The switch has at least two terminals, and includes a plurality of pairs of transistors, each one of said transistors coupled between a reference potential and a common transmission line which is coupled to one of the pair of terminals. A pair of topside conductors are disposed over the substrate to couple the transistors through plated vias to a bottom ground plane conductor. The switch further includes a series connected transistor disposed between the r.f. line and a second one of the terminals of the circuit.

Abstract: An array antenna is disclosed wherein each one of the antenna elements includes at least two concentric slots formed in a conductive sheet. The conductive sheet is disposed on a dielectric support and a ground plane is found on the opposite surface of such support. The inner one of the slots enables the outer slot to radiate radio frequency energy having a wavelength greater than the circumference of such outer slot. When such antenna includes an additional concentric slot the antenna is adapted to operate over a pair of frequencies separated by greater than twenty percent while enabling the array antenna to have satisfactory grating lobe characteristics.

Abstract: An antenna element is disclosed having a printed circuit parallel plate region with a parabolically shaped reflecting wall and a flared radiating section. The flared radiating section is disposed along an aperture which intersects the axis of the parabola at an acute angle. A microstrip feed formed integrally with the printed circuit parallel plate region is offset from the reflecting wall and is adapted to introduce radio frequency energy at the focal point of such reflecting wall. Load material is disposed adjacent to the focal point to absorb radio frequency energy reflected by the aperture thereby improving the VSWR of the feed. Such arrangement enables close element-to-element spacing in an array, thereby substantially eliminating grating lobes while enabling intermeshing of the elements to provide port and starboard array antennas.

Abstract: A radio frequency oscillator having an improved varactor mounting structure and tuning slug mounting arrangement is disclosed. The varactor mounting structure includes a coaxial transmission line, one end of the center conductor thereof being capacitively coupled to the cavity of the oscillator and the other end being coupled to the varactor. The length of the center conductor is .lambda./2 where .lambda. is the nominal operating wavelength of the oscillator and hence, while disposed outside the cavity, such varactor appears, electrically, within the cavity. A feed wire for coupling a direct current control signal to the varactor is connected between the housing of the oscillator and the center conductor at a point .lambda./4 from the capacitively coupled end of the center conductor. Therefore, while such wire enables direct current to pass between the housing and the varactor, such wire is electrically isolated from the radio frequency energy in the cavity.