Abstract: An antenna array employing continuous transverse stubs as radiating elements includes a first conductive plate structure including a first set of continuous transverse stubs arranged on a first surface, and a second set of continuous transverse stubs arranged on the first surface, wherein a geometry of the first set of continuous transverse stubs is different from a geometry of the second set of continuous transverse stubs. A second conductive plate structure is disposed in a spaced relationship relative to the first conductive plate structure, the second conductive plate structure having a surface parallel to the first surface. A relative rotation apparatus imparts relative rotational movement between the first conductive plate structure and the second conductive plate structure.

Abstract: A waveguide rotary joint includes a first waveguide portion for receiving a microwave signal, a second waveguide portion for outputting the received microwave signal, and a conductive pin including a first end and a second end distal from the first end, the first end arranged in and RF coupled to the first waveguide, and the second end arranged in and RF coupled to the second waveguide, and a choke cavity is arranged between the first waveguide portion and the second waveguide portion. The first waveguide and the second waveguide are rotatable relative to each other about a longitudinal axis of the conductive pin.

Abstract: An array antenna includes radiating antenna elements arranged to form an antenna aperture, the radiating antenna elements including a first group and a second group of radiating antenna elements; a corporate feed network configured to feed the radiating antenna elements, wherein the corporate feed network includes a 4-port device including a sum port, a difference port, a first signal port and a second signal port, with the first signal port coupled via the corporate feed network to the first group of radiating elements and the second signal port coupled via the corporate feed network to the second group; a first phase shift element proximal to the antenna aperture to introduce a first predetermined phase shift to the first group of radiating antenna elements; and a second phase shift element proximal to the second signal port to introduce a second predetermined phase shift to the second group of radiating antenna elements.

Abstract: A radio frequency (RF) transmission-line structure includes a parallel-plate transmission line formed from a first conducting plate and a second conducting plate. The second conducting plate is spaced apart from the first conducting plate and substantially parallel to the first conducting plate. A support member is attached to the first and second plates and is operative to maintain a fixed mechanical spacing between the first conducting plate and the second conducting plate. The transmission-line structure further includes at least one feature configured to isolate or suppress RF interaction of the support member with RF fields within the parallel-plate transmission line.

Abstract: An array antenna includes radiating antenna elements arranged to form an antenna aperture, the radiating antenna elements including a first group and a second group of radiating antenna elements; a corporate feed network configured to feed the radiating antenna elements, wherein the corporate feed network includes a 4-port device including a sum port, a difference port, a first signal port and a second signal port, with the first signal port coupled via the corporate feed network to the first group of radiating elements and the second signal port coupled via the corporate feed network to the second group; a first phase shift element proximal to the antenna aperture to introduce a first predetermined phase shift to the first group of radiating antenna elements; and a second phase shift element proximal to the second signal port to introduce a second predetermined phase shift to the second group of radiating antenna elements.

Abstract: An antenna array employing continuous transverse stubs as radiating elements includes a first conductive plate structure including a first set of continuous transverse stubs arranged on a first surface, and a second set of continuous transverse stubs arranged on the first surface, wherein a geometry of the first set of continuous transverse stubs is different from a geometry of the second set of continuous transverse stubs. A second conductive plate structure is disposed in a spaced relationship relative to the first conductive plate structure, the second conductive plate structure having a surface parallel to the first surface. A relative rotation apparatus imparts relative rotational movement between the first conductive plate structure and the second conductive plate structure.

Abstract: A waveguide rotary joint includes a first waveguide portion for receiving a microwave signal, a second waveguide portion for outputting the received microwave signal, and a conductive pin including a first end and a second end distal from the first end, the first end arranged in and RF coupled to the first waveguide, and the second end arranged in and RF coupled to the second waveguide, and a choke cavity is arranged between the first waveguide portion and the second waveguide portion. The first waveguide and the second waveguide are rotatable relative to each other about a longitudinal axis of the conductive pin.

Abstract: An apparatus and method is presented for calibrating an output(s) of an inertial measurement unit (IMU) using rotational rate as a reference. Calibrating the IMU output(s) is performed by comparing the IMU output(s) to expected output(s), where the expected output(s) are determined based on the known rate of rotation of the IMU and the centripetal force acting on the IMU due to known rate of rotation. By analyzing the differences between the expected IMU output(s) and the IMU output(s), it is possible to determine a correction factor that, when applied to the IMU output(s), calibrates the IMU output(s) by correcting for measurement errors.

Abstract: A waveguide to parallel-plate transition is provided which includes a waveguide, an E-plane waveguide bend, an H-plane waveguide bend and a parallel-plate transmission line arranged in sequence. The E-plane waveguide bend is configured to bend a direction of a radio frequency (RF) field between the waveguide and the H-plane waveguide bend by approximately 90 degrees in an E-plane. The H-plane waveguide bend is configured to bend a direction the RF field between the E-plane waveguide bend and the parallel-plate transmission line by approximately 90 degrees in an H-plane, and the parallel-plate transmission line includes a slot through which the RF field can flow between the H-plane waveguide bend and the parallel-plate transmission line.

Abstract: A radio frequency (RF) device includes an RF transmission line structure having opposing boundary walls with a non-rectilinear form factor, and a feed structure configured to introduce RF energy into an area between the opposing boundary walls to illuminate the RF transmission line structure with the RF energy across the non-rectilinear form factor. The feed structure includes a plurality of traveling-waveguide-fed leaky line-segment structures, each configured to launch the RF energy into the area with a propagation direction having an oblique angle relative to an axis of the line-segment structure.

Abstract: A radio frequency (RF) transmission-line structure includes a parallel-plate transmission line formed from a first conducting plate and a second conducting plate. The second conducting plate is spaced apart from the first conducting plate and substantially parallel to the first conducting plate. A support member is attached to the first and second plates and is operative to maintain a fixed mechanical spacing between the first conducting plate and the second conducting plate. The transmission-line structure further includes at least one feature configured to isolate or suppress RF interaction of the support member with RF fields within the parallel-plate transmission line.

Abstract: An electronically scanned array (ESA) antenna includes a main line along which an electromagnetic traveling wave may propagate and a plurality of array elements distributed along the main line. Each of the plurality of array elements includes a branch line; an antenna radiator at one end of the branch line; an electronically controllable reflection phase shifter at the opposite end of the branch line; a directional coupler which couples energy between the main line and the branch line.