Abstract: A radio frequency (RF) test hat. The RF test hat may comprise: a body having a substantially rectangular portion with open forward and aft ends, an end cap, arm and strap assembly, absorber material, a receiving antenna, lens, and upper and lower mesh screens. The end cap may couple to the open forward end of the body. The arm and strap assembly may hingedly couple to the open aft end of the body. The absorber material may be within the end cap. The receiving antenna may be disposed within the first absorber material and may measure the intensity of a beam of electromagnetic radiation. The lens may be located within the middle portion of the body and may spread the beam across a larger surface area of the absorber material. The upper and lower mesh screens may be disposed between the end cap and lens and may comprise openings that are substantially hexagonal in shape.

Abstract: A radio frequency (RF) test hat. The RF test hat may comprise: a cylinder having forward and aft ends, end cap, arm and strap assembly, first and second absorber materials, a receiving antenna, and lens. The end cap may couple to the forward end of the cylinder. The arm and strap assembly may hingedly couple to the aft end of the cylinder and may be configured to mount the RF test hat onto a pod or transmitting antenna. The first absorber material may be located within the forward end of the cylinder. The second absorber material may be located near the aft end of the cylinder. The receiving antenna, which may be disposed within the first absorber material, may measure the intensity of a beam of electromagnetic radiation. The lens, which may be located within the middle portion of the cylinder, may spread the beam across a larger surface area of the first absorber material.

Abstract: An RF test hat. The RF test hat may comprise: a body having a substantially rectangular portion with open forward and aft ends, an end cap, arm and strap assembly, absorber material, a receiving antenna, lens, and upper and lower mesh screens. The end cap may couple to the open forward end of the body. The arm and strap assembly may hingedly couple to the open aft end of the body. The absorber material may be within the end cap. The receiving antenna may be disposed within the first absorber material and may measure the intensity of a beam of electromagnetic radiation. The lens may be located within the middle portion of the body and may spread the beam across a larger surface area of the absorber material. The upper and lower mesh screens may be disposed between the end cap and lens and may comprise openings that are substantially hexagonal in shape.

Abstract: A radio frequency (RF) test hat. The RF test hat may comprise: a cylinder having forward and aft ends, end cap, arm and strap assembly, first and second absorber materials, a receiving antenna, and lens. The end cap may couple to the forward end of the cylinder. The arm and strap assembly may hingedly couple to the aft end of the cylinder and may be configured to mount the RF test hat onto a pod or transmitting antenna. The first absorber material may be located within the forward end of the cylinder. The second absorber material may be located near the aft end of the cylinder. The receiving antenna, which may be disposed within the first absorber material, may measure the intensity of a beam of electromagnetic radiation. The lens, which may be located within the middle portion of the cylinder, may spread the beam across a larger surface area of the first absorber material.

Abstract: A compact broadband antenna. The antenna includes a first mechanism for receiving input electromagnetic energy. A second mechanism provides radiated electromagnetic energy upon receipt of the input electromagnetic energy. The radiated electromagnetic energy is provided via an antenna element having one or more angled surfaces. A third mechanism directs the radiated electromagnetic energy in a specific direction. In a more specific embodiment, the third mechanism includes a reflective backstop that is selectively positioned behind the second mechanism to reflect back-radiated energy forward of the second mechanism, thereby causing reflected electromagnetic energy to combine in phase with forward-radiated energy from the second mechanism. The third mechanism further includes plural layers of dielectric material.

Abstract: A hood is provided for verifying the performance of the missile. The hood includes one or more sense antennas having the same polarization as the antennas within the missile to be tested. The hood further includes one or more elliptic-to-circular polarization converters designed to reduce the axial ratio of the signal received from the missile. The elliptic-to-circular polarization converters convert the signal from the missile to a substantially pure circular polarized signal which is then sensed by the sense antennas.

Abstract: A hood is provided for verifying the performance of the missile. The hood includes one or more sense antennas having the same polarization as the antennas within the missile to be tested. The hood further includes one or more elliptic-to-circular polarization converters designed to reduce the axial ratio of the signal received from the missile. The elliptic-to-circular polarization converters convert the signal from the missile to a substantially pure circular polarized signal which is then sensed by the sense antennas.

Abstract: An antenna is described which includes a plurality of antennas stacked on top of each other in a compact cavity. Input match and radiation gain can be enhanced by the application of a capacitor and inductor in the feed of the spiral lowest in the cavity. The antenna can fit into a very compact space while providing circular polarization over the desired bands of the antennas that are isolated.

Abstract: An antenna is provided that receives electromagnetic radiation and includes a dielectric substrate (106). First and second spirals (60 and 70) on a first surface of the substrate (106) radiate the electromagnetic radiation. A third spiral (80) is utilized on a second surface of the substrate (106) and is substantially underneath one of the first and second spiras(60 and 70). The resulting spiral antenna is compact and has multioctave bandwidth capability.

Abstract: A multiple frequency band, multi-spiral antenna that employs filters to pass the band of one spiral and reject the band of the other spirals. Additional isolation is achieved by arranging adjacent spirals to have opposite senses. All the isolation and filtering is accomplished within the body of the antenna. The antenna includes two, two-arm spirals. The higher frequency spiral resides in the interior of the lower frequency spiral. The two spirals are concentric about each other, and lie on the same plane. A balun and filter circuit is connected to the two spirals, and is disposed within the antenna body.

Abstract: An antenna comprising a substrate, and low band and high band opposite sense spiral antennas formed on the substrate to provide for a common aperture isolated dual frequency band antenna. The high band spiral antenna is formed adjacent the center of the substrate while the low band spiral antenna is formed adjacent the periphery of the substrate. The high frequency end of the low band antenna is truncated at the low frequency end of the high band antenna, and the low frequency end of the high frequency antenna is truncated at the high frequency end of the low band antenna 21 to provide for mutual isolation between the frequency bands.

Abstract: A missile guidance antenna that is conformal to the missile surface, dual-polarized and broadband. Slotline notch array elements (30, 52) are inclined toward boresight for both the E and H-planes. This inclination directs a greater portion of the energy toward the front of the missile. The additional energy directed forward reduces the nullifying effects of the metallic skin on the tangential E-field and enhances the performance of the other polarization. The slotline elements (30, 52) can be packed with spacing close enough to allow for electronic beam steering without creating grating lobes in the field at the highest frequency of operation.