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 circular low noise amplifier package having an X-band MMIC low noise amplifier disposed therein, that may be preferably used with an existing stripline receiver board employed in a missile. The package has three input/output ports symmetrically located around the package, including DC bias, RF input, and RF output ports. The package mounts directly into the stripline receiver board as a drop-in replacement for an isolator used in the existing stripline receiver board. The circular low noise amplifier package comprises a top cover, an upper RF gasket, a package lid, a hermetic low noise amplifier module containing a low noise amplifier chip, a lower RF gasket, and a bottom cover. The amplifier module has feedthrough pins that extend through the outer wall thereof and couple to the low noise amplifier chip. The top and bottom covers are used to secure the amplifier package to the stripline receiver board. The upper and lower RF gaskets aid in improving an RF ground.

Abstract: A surface-protected composite article, such as a missile component, is prepared with a heat-sink substrate, a first composite layer of an pre-ceramic-matrix structural composite material, and a second composite layer of a reinforced silicone pre-ceramic material. The silicone material is co-curable with the organic matrix of the first composite layer. The silicone at the surface of the article is thereafter converted to a silica refractory by an appropriate treatment such as exposure to an oxygen-rich plasma or a high-surface temperature. The silica protects the surface of the composite material.

Abstract: A broadband, high power balun which includes plural sets of first and second coaxial cables. Each cable has a center conductor and a shield conductor. Each shield conductor of each cable within each set is connected to a shield conductor of the other coaxial cable of the set. The first input lead is connected to a first end of a center conductor of a first coaxial cable of each set. The second input lead is connected to a first end of a center conductor of a second coaxial cable of each set. A second end of a center conductor of a first coaxial cable of a set of coaxial cables provides an output lead for the balun. A second end of a center conductor of a second coaxial cable of a set of coaxial cables provides an output lead for the balun. A second end of each remaining center conductor of each coaxial cable of each set of coaxial cables is connected to a second end of a center conductor of a coaxial cable of another set of coaxial cables.

Abstract: A pressure activated flow controller for use with a Joule-Thomson valve having a diaphragm actuator that is located outside a dewar, and which is not cooled. The diaphragm actuator limits flow based on gas pressure supplied to the dewar from a gas supply, not temperature, and does not impede cooldown of a device coupled to the dewar. The diaphragm actuator comprises a diaphragm and load plate that exert a force to open the Joule-Thomson valve. A wave spring provides a force to close the Joule-Thomson valve, thus balancing the back pressure of the gas supply. The diaphragm actuator is compact, and limits flow based on gas supply pressure, not temperature. The present invention thus uses pressure regulation instead temperature regulation to achieve flow control.

Abstract: A system (10') for generating a missile guidance gain factor adapted for use with guided missiles. The inventive system includes a guidance control system (52) for obtaining current guidance parameters(55, 57) including ideal navigation gain, closing rate, line of sight rate, missile maneuverability, and missile velocity parameters. Software (56) running on a guidance control processor (54) computes a current guidance gain factor reflective of the current maneuverability of the missile from the guidance parameters (55, 57). In the illustrative embodiment, the system 10' further includes a nonlinear notch circuit (56) that generates an acceleration command (59) from the guidance parameters (55, 57) that varies in response to varying missile maneuverability parameters (57). The guidance control system (10') includes a conventional guidance law computation circuit (54, 55) and electromagnetic sensing equipment (52).

Abstract: A locking assembly that mechanically locks an attachment bolt, such as one used to secure a missile launcher to an aircraft, for example, thus preventing the bolt from vibrating loose as a result of vibration experienced during flight. The locking assembly has a spring loaded locking nut that mechanically engages a hex head of an extension shaft that is coupled to the attachment bolt. Transverse pins permit axial movement of the locking nut but prevent rotation thereof. A socket is used to push the locking nut away from the hex head of the extension shaft, so that the attachment bolt can be loosened or tightened. When the socket is removed, a spring pushes the locking nut over the hex head of the extension shaft, locking the attachment bolt and preventing it from turning.

Abstract: Apparatus and methods for transitioning between opposite sides of adjacent stripline circuit boards. An orthogonal coaxial connection between opposite sides of the stripline circuit boards is provided wherein a center pin of a coax connector is disposed through the first stripline circuit board and the center trace of one of the stripline circuit boards and through the second board. The center pin is soldered or otherwise electrically attached to a small conductor island pad isolated from the ground plane of the second board and to the plated through hole. The ground of the coaxial connector is connected to the ground plane of the second board adjacent to the isolated conductor island pad.

Abstract: A suspension lug system for use with a jettisonable weapon that provides a mechanical interface between the weapon and a multiplicity of aircraft. The system has a dual-function lug that is disposed in a well when it is in a stowed position, and that is pivotable in opposite directions on a transverse pivot pin. A first end of the lug is configured as a saddle lug that is exposed above the outer surface when the lug is rotated into a saddle-deployed position. The second end of the lug is configured as a clevis that is exposed above an outer surface of the system when the lug is rotated into a clevis-deployed position. A spring is coupled to the lug that spring loads it and returns it to a stowed position when it is not engaged with the ejector release unit to preserve the outer contour of the weapon.

Abstract: A technique for operating a communication link in RF proximity to an operational radar. A data link waveform is employed which allows a data link receiver to detect an alert indication during normal radar operation. When the alert is detected, the system briefly inhibits radar operation to receive the information content of the data link message. A data link message rate is selected to keep the impact to radar operation at a minimum.

Abstract: A diaphragm pressure regulator comprising a housing having first and second sections. The first section 1a has a cavity or vacuum space, and a wave spring is disposed in the vacuum space, a load distributor is disposed adjacent to the wave spring, and a diaphragm seals the cavity and secures the wave spring and load distributor in the cavity. The second section of the housing comprises a movable and sealable vent stem that moves in response to movement of the diaphragm, and a vent opening for venting the interior of the second section of the housing to external pressure in response to motion of the diaphragm. The diaphragm pressure regulator may be preferentially used in an upper atmospheric system that needs to maintain a specified pressure, but requires venting capabilities. Such systems include missile systems that fly into the upper atmosphere.

Abstract: A system and method for target reacquisition and aimpoint selection in missile trackers. At the start of iterations through the process, distance classifier correlation filters (DCCFs) memorize the target's signature on the first frame. This stored target signature is used in a subsequent confidence match test, so the current sub-frame target registration will be compared against the stored target registration from the first frame. If the result of the match test is true, a patch of image centered on the aimpoint is used to synthesize the sub-frame filter. A sub-frame patch (containing the target) of the present frame is selected to find the target in the next frame. A next frame search provides the location and characteristics of a peak in the next image, which indicates the target position. The DCCP shape matching processing registers the sub-frame to the lock coordinates in the next frame. This process will track most frames, and operation will repeat.

Abstract: An optical correction technique which utilizes a pair of toroidal optical elements which are translated axially to provide dynamic correction of astigmatic aberrations induced by conformal/aspheric domes and windows as a function of sensor gimbal angle. This correction technique provides dual axis, variable optical power correction within the dynamic operation of gimballed optical sensors, and is particularly suited to correction of aberrations introduced by conformal/aspheric domes and windows used in both missile and airborne fire control systems.

Abstract: A missile has a body with a substantially circular nose opening therein, and a ceramic radome sized to cover the nose opening. A compliant metallic circular "T"-flexure element is disposed structurally between the radome and the body and is integral with the body. A niobium-containing washer is disposed between the radome and the "T"-flexure element. The "T"-flexure element includes an elongated compliant arm region and a cross bar region positioned adjacent the radome such that the niobium-containing washer is situated between a lower margin surface of the radome and an upper side of the crossbar region. A first brazed butt joint is formed between the lower margin surface of the radome and an upper surface of the niobium-containing washer, while a second brazed butt joint is formed between a lower surface of the niobium-containing washer and the crossbar region of the "T"-flexure element.

Abstract: Inexpensive and reliable apparatus for blanking the signal path between an antenna and a transmitter or a receiver to protect them from harmful radiation in the absence of power forms supplied thereto. The apparatus is preferably formed as a printed circuit waveguide switch window having a plurality of parallel conductors, such as metal wires or printed circuit traces, disposed on a dielectric substrate. The waveguide switch window is secured between two sections of waveguide. The conductors have a predetermined separation and width that are designed to appear as a solid metal surface that rejects radiation over a wide bandwidth. A bias terminal is coupled to the plurality of conductors, and insulating material is disposed between the bias terminal and the conductors to insulate the top portion of the grid array from the adjacent waveguide. The lower portion of the grid array is grounded to the adjacent waveguide.

Abstract: A rocket ignition system adapted for use with a missile having a rocket motor is provided. The rocket ignition system comprises (a) a first circuit for detecting an optical impulse and providing a first signal in response thereto; (b) a second circuit for detecting a pressure wave and providing a second signal in response thereto; and (c) a third circuit for launching the missile in response to the first and second signals. The rocket ignition system, which is easily adapted to existing missiles and rocket propelled devices, can reliably distinguish between the firing of a primer and other acoustic events occurring in noisy environments, such as a battlefield.

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: A compensation circuit adapted to receive an input signal for a circuit element to be compensated. The input signal is used as an address to a memory at which a compensated signal is stored. The stored compensated signal is output to the circuit element as the compensated signal therefor. In a specific implementation, the command input is received by a shift register. The shift register converts a serial input to a parallel output. The parallel output of the shift register is combined with the output of a temperature sensor to provide an address for the memory. The command input data includes an address to the particular circuit element to be compensated. The temperature data is used to select a particular page of memory and the remainder of the command input data is used to select data from that page for output as the compensated signal for the selected element. In the illustrative embodiment, the components compensated are automatic gain control amplifiers.

Abstract: A composite structure is fabricated by providing a mandrel having a winding surface and placing a shaped plug into the winding surface so that it extends from the winding surface. An uncured composite material is wound over the winding surface of the mandrel and laterally adjacent to the shaped plug. The composite material is cured, and the shaped plug and mandrel are removed. The shaped plug may be provided with an overlying bushing that is bonded to the composite material during curing and is not removed with the remainder of the shaped plug.

Abstract: An in-line valve flow controller for a Joule-Thomson cryostat. The controller has an in-line valve stem that is part of, and is collinear with, an actuation stem of the cryostat. Both the in-line valve stem and actuation stem sit in an orifice of the Joule-Thomson cryostat. This arrangement automatically positions the valve stem over its valve seat. The in-line valve flow controller integrates with a temperature dependent snap disk that is used to close the valve stem against the valve seat. Initial flow rate is determined only by the diameter of the orifice of the Joule-Thomson cryostat, and not by valve position. Bypass flow is aso set by the diameter of the orifice, which is not subject wear, and the valve stem prevents contaminates from clogging the orifice.