Abstract: An alignment device mounts to a missile system such that the view of a missile seeker is limited to limited fields of view at predetermined positions relative to a known reference such as the missile centerline. Once the alignment device is mounted to the missile system, an energy source emitting energy viewable by the seeker is located within a field of view. Once the seeker has locked-on to the energy source in a limited field of view, the pointing angle of the seeker can be observed by a measurement device communicating with the missile controller. Any pointing angle observed by the measurement device which differs from the known position defined by the alignment device, represents a displacement error of the seeker. Appropriate compensation is then applied to the missile controller such that alignment errors are accounted for.

Abstract: One version of the invention relates to a laser detection system that includes a ball lens and a plurality of fiber optic bundles placed adjacent the ball lens so that incoming light rays are focused onto the bundles by the ball lens. In one particular version of the invention, a ball lens is one that can provide an almost infinite number of “principal” axes for off-axis light. Each fiber optic bundle is aimed in a different direction from each other bundle so that each bundle will have a different FOV even though the same ball lens is used to focus the incoming light rays.

Abstract: A fire control system for a short range guided missile in which the system is contained on a vehicle such as a track vehicle that can be easily camouflaged from the enemy and including video means for acquiring a target desired to be destroyed and utilizing this video information as reference information in an automatic target handoff correlator which correlates the reference information from video signals from a missile that was launched from the vehicle and guided by a missile control computer to the field of view of the selected target with the automatic target handoff correlator comparing the reference video signals and the seeker video signals from the missile to place the target in the center of the field of view of the seeker and once this is done a missile autotracker is commanded to lock-on and guide the missile to the selected target.

Abstract: The invention relates to a target-detection and target-alignment device for a missile system whose field of view is expanded by a wide-angle lens system, which does not contain any optical components which must be additionally moved, and which is equipped with an integrated system for correction of homogeneity of the ambient conditions. Two radiometers or photometers are connected to two emission surfaces positioned on opposite sides of the image of the field of view to adjust the angle of the target detector to compensate for mismatch of the output signals of the emission surfaces.

Abstract: A system (16) for tracking a missile (22) in flight, the missile (22) having an optical beacon generator (32) that outputs a modulated signal (26) having a predetermined frequency, including an optical system (50, 52, 54) for transmitting image data along an optical path (68) onto an array of detectors (55), such that each detector in the array (55) receives substantially simultaneously the image data from the optical system (50, 52, 54). The system (16) further includes means for processing (46) the image data transmitted onto the array of detectors (55) in order to locate the optical beacon (32).

Abstract: A system (16) for tracking a missile (22) in flight, the missile (22) having an optical beacon generator (32) that outputs a modulated signal (26) having a predetermined frequency, including an optical system (50, 52, 54) for transmitting image data along an optical path (68) onto an array of detectors (55), such that each detector in the array (55) receives substantially simultaneously the image data from the optical system (50, 52, 54). The system (16) further includes means for processing (46) the image data transmitted onto the array of detectors (55) in order to locate the optical beacon (32).

Abstract: An interceptor missile including an infrared radiation detection subsystem and a window assembly in the hull of the missile optically coupled to the infrared radiation detection subsystem. The window assembly includes an inner window, an outer window, and a support subsystem between the inner and the outer windows defining a plurality of infrared transparent fluid flow cooling channels between the inner and outer windows. A source of fluid coupled to the cooling channels for cooling the outer window without adversely affecting the optical properties of either window.

Abstract: Apparatus for providing simultaneous jamming of a number of missiles is disclosed comprising a plurality of reticles each having a pattern therein which provides necessary spin frequency and carrier frequency (if required) for the missile to be jammed. The reticles are arranged in series and modulate a source of radiation and generate the spin and carrier frequencies by blocking or rejecting radiation within the spectral passband of the missile to be jammed.

Abstract: A robotically controlled steerable gimbal mounted virtual broadband hyperspectral sensor system and methods provide a highly mobile, rapidly responsive and innovative system of locating targets and exploiting hyperspectral and ultraspectral imaging and non-imaging signature information in real-time from an aircraft or ground vehicles from overhead or standoff perspective in order to discriminate and identify unique spectral characteristics of the target. The system preferably has one or more mechanically integrated hyperspectral sensors installed on a gimbal backbone and co-boresighted with a similarly optional mounted color video camera and optional LASER within an aerodynamically stable pod shell constructed for three-dimensional stabilization and pointing of the sensor on a direct overhead or off-nadir basis.

Abstract: A method of countermeasuring heat seeking missiles is disclosed in which an infrared source is spatially modulated by providing a beam from the source which is swept past a point in space to produce pulsed infrared energy at this point. In one embodiment the beam is swept around a 360° azimuth for omnidirectional protection.

Abstract: A modulated infrared source is disclosed in which spatial modulation is accomplished by the rotation of beam forming optics about an infrared source in which a portion of the energy in the beam produced includes energy coming directly from the IR source without being reflected. Close to 100% of the energy from the infrared source is focused by rotating parabolically shaped elements, such that energy losses due to the modulation technique are minimized. The speed of the rotation of the reflective optics is minimized while maintaining sufficiently high modulation frequencies by the provision of four beams from a single source.

Abstract: A modulated infrared source is disclosed in which spatial modulation is accomplished by the sweeping of an infrared beam past a point in space. In one embodiment close to 100% of the energy from the infrared source is focused by rotating optics including parabolically shaped reflectors about the source such that energy losses due to the modulation technique are minimized due to a single reflection of the energy from the IR source. The speed of the rotation of the reflective optics is minimized while maintaining sufficiently high modulation frequencies by the provision of four beams from a single source. In another embodiment a squirrel cage reflecting system is provided in which the energy from the IR source is reflected twice.

Abstract: The invention relates to a method for determining the relative movement between a target tracking missile and a target being located at a target distance from said missile. The missile is equipped with an image processing seeker head provided with a seeker detecting said target. The seeker head observes the target in an observation direction. A target image is generated on the seeker. The size of the target image depends on the observation direction. The target moves with a target velocity relative to the missile. The method has the method steps of: defining a seeker head-fixed coordinate system; defining a maximum absolute size of said target; measuring further relevant quantities; and running a recursive algorithm in order to obtain estimated values of a three-dimensional vector of the target velocity in the seeker head-fixed coordinate system by using as inputs the defined maximum absolute size of the target and the image dimension appearing on the seeker as well as further relevant quantities.

Abstract: A method for guiding an intercepting missile to a body-to-body contact with an airborne target in the atmosphere. The method includes the steps of guiding the intercepting missile to within an appropriate distance from the airborne target, illuminating the airborne target, using an illuminator carried by the intercepting missile, acquiring an image of the illuminated airborne target and, steering the missile in accordance with an aimpoint on the image.

Abstract: A two-color infrared warning device, having both wide-angle and narrow-angle search capabilities, and a directional countermeasure device are mounted on a gimbal pointing in the same direction. The warning device and gimbal are initially operated in a wide-angle, step-stare mode to search for threats. When a potential hostile target is found, the warning device changes to a narrow-angle mode to determine whether the potential target is hostile. When a hostile target is identified, the directional countermeasure device, which is pointed at the target by virtue of its mounting with the warning device on the gimbal, is activated.

Abstract: A method to determine the direction in which a spinning projectile is traveling. A solar sensor array on the projectile is used to calculate the orientation of the axis of rotation of the projectile with respect to a known solar field and a magnetometer sensor array is used to calculate the orientation of the axis of rotation of the projectile with respect to a known magnetic field, both fields being represented by respective vectors having magnitude and direction. With the known and calculated orientations, the pointing direction may be obtained by vector combination.

Abstract: A ball joint gimbal system which provides for a precise line-of-sight stabilization of a gimballed mirror that rides on a ball and its associated support structure. The mirror is positioned by four braided lines. The brained lines are driven by four servo motor with each servo motor being coupled to one of four capstan shafts. Each of the braided lines is wound around one of the four capstan shafts. The braided lines are positioned by optical shaft encoders. The low inertia of the gimballed mirror and the positioning of the mirror by the braided lines result in an extremely accurate and fast scanning optical pointing system. Inertial gimbal stabilization of the line of sight to a target is by a stabilization algorithm utilizing body rate information from body sensors which are components of the missile for providing autopilot and navigation functions for the missile.

Abstract: A control system for a rolling missile that has a seeker head including an optical system and a heat detector assembly. The optical system including a primary reflector, a secondary reflector, a reticle/lens assembly, and a fiber optics assembly operatively associated with the reticle/lens assembly. The fiber optics assembly is constructed so as to translate images appearing near the optical axis of the optical system to a radially displaced point on the reticle/lens assembly to provide a more efficient chopping of the image by the reticle/lens assembly thus providing continuous pulses to the heat sensitive detector assembly.

Abstract: An aircraft display and control system generally includes a processor, a cursor control and selection device, an aeronautical information database, a geographic database, and a plurality of display devices. Users, such as an aircraft pilot and copilot, can perform flight plan entry and modification by manipulating graphical information on the display devices using cursor control. In one embodiment, the present invention allows multiple members of an aircraft crew to share control of common flight information display areas, aids the crew's situational awareness by providing software-implemented dynamic symbology and highlighting to indicate cursor location, current panel of entry, and current focus for keyboard and cursor events.

Abstract: The present invention relates to a system for sweeping a laser beam in a preset pattern, while, at the same time, directing the pattern to any area in a predetermined scanning area. The invention is particularly useful in LADAR applications. In one version of the invention, a series of optical prisms are arranged in concentric tubes so that the prisms have a common optical path. The tubes and, hence, the prisms, may be independently rotated by precision electric motors coupled to gear rings on the tubes.

Abstract: A missile tracking and deflection system for protecting a platform includes a missile warning system for detecting the presence of a missile and generating a warning signal. A countermeasure processor receives the warning signal and analyzes characteristics of the missile to prioritize a trajectory signal. A track processor receives the trajectory signal and generates a pointer signal. The system also includes a receiver, which is positioned by a pointer that receives the pointer signal, for receiving a passive and/or active signature of the missile to confirm the presence thereof. The countermeasure processor then directs a laser beam at the missile to determine its operational parameters and receives an active signature from the missile.

Abstract: The present invention relates to a process and a device for guiding a flying craft onto a target, the device (1) comprising a detector (D) pointed at the target in such a way that a projection of the latter is situated on a field of measurement of the detector (D), a computation unit (UC) for determining guidance commands, and members (6) carrying out the guidance. According to the invention, the said device (1) furthermore comprises computation means (C3, C4) for determining commands for varying attitudes of the said flying craft making it possible to center the said projection with respect to a first direction of the measurement field, and the line of sight of the detector (D) is moveable and is controlled in such a way as to center the said projection with respect to a second direction of the measurement field, which is different from the said first direction.

Abstract: A reticle for a guidance seeker for spinning projectiles comprises a substrate; a pattern of a plurality of alternating light modulating structures, such as opaque and light transmitting, or light absorbing and light reflecting areas on the substrate such that an image of a target moving on the substrate will generate a plurality of pulses corresponding to the number of lines crossed by the image, the number of pulses increasing as the image moves outwardly from the center of the reticle; and a distinguishable, unambiguous, and singly periodic feature of the pattern, which is readily detectable every time the target image moves circumferentially, completing a full circle around the center of the reticle.

Abstract: Means and method for jamming IR radiation-seeking threat missiles comprising means for generating wavetrains of randomized pulses of radiation of the same wavelengths at which the threat missiles are operating. The apparatus consists generally of radiation-generating means, means for pulse-modulating the radiation-generating means or the radiation itself with a wavetrain of random or pseudo-random pulses, and means for directing the modulated radiation at a target.

Abstract: A passive suspension system for supporting an instrument relative to a rigid support structure while preserving angular alignment of the instrument. The suspension system includes an instrument platform, the instrument being secured to the platform, and first and second vibration isolator systems. The first ends of the isolator systems are attached to the rigid support structure so that axes of the vibration isolators extend transverse to the instrument axis. The first and second isolator systems resist motion transverse to the instrument axis and provide shock and vibration isolation transverse to the instrument axis. First, second and third stabilizing struts extend parallel to each other and the instrument axis, and are of equal length. A first set of bearings connects ends of the struts to the instrument platform in a spaced relationship, and allows motion transverse to the struts. A second set of bearings connects opposing ends of the struts to the rigid support structure in a spaced relationship.

Abstract: An imaging self-referencing target tracker (10) for a laser weapon (12). The weapon generates a first beam of radiation (14) that engages a target (16) to form a beam hit spot (20) thereon. In a first embodiment, a target illuminator (22) (variant 1) illuminates the target with a second beam of radiation (23a). An optics subsystem (30) receives and separately images the first and second beams (23b, 24) of radiation. In a second embodiment, a blocking filter (40) is implemented rather than an illumination laser to pass only radiation at the target wavelength, thereby ensuring that the first and second beams of radiation are separately imaged. A controller (32) is programmed to steer the first and second beams of radiation to the desired target aim point (18) in response to information from the imaged first and second beams of radiation.

Abstract: A missile seeker. The inventive missile seeker includes a dome within which a novel optical arrangement is retained. The optical arrangement includes a first prism mounted for rotation about an optical axis and a second prism mounted for rotation about the optical axis. In the illustrative embodiment, the first and second prisms are Risley prisms. In addition, the illustrative implementation includes a first motor arrangement for rotating the first prism about the optical axis and a second motor arrangement for rotating the second prism about the optical axis. A controller is provided for activating the first and second motors to steer the beam at an angle &phgr; and nod the beam at an angle &thgr;. In a specific implementation, the first prism and/or the second prism have at least two surfaces contoured to correct for optical aberration. A teaching is provided to contour the surfaces to correct for astigmatism, coma, trefoil and other non-rotationally symettric abberation.

Abstract: A ball joint gimbal system which provides for a precise line-of-sight stabilization of a gimballed mirror that rides on a ball and its associated support structure. The mirror is positioned by four braided lines. The brained lines are driven by four servo motor with each servo motor being coupled to one of four capstan shafts. Each of the braided lines is wound around one of the four capstan shafts. The braided lines are positioned by optical shaft encoders. The low inertia of the gimballed mirror and the positioning of the mirror by the braided lines result in an extremely accurate and fast scanning optical pointing system. Inertial gimbal stabilization of the line of sight to a target is by a stabilization algorithm utilizing body rate information from body sensors which are components of the missile for providing autopilot and navigation functions for the missile.

Abstract: One aspect of the invention relates to a laser ranging system.

Abstract: A fuzing system for non-spinning or substantially non-spinning weapons is implemented by means of wide angle optics providing at least forward-hemisphere coverage, an array of infrared detectors and a microprocessor for image and data processing, aim-point selection, directional-warhead aiming and skewed-cone fuzing. The skewed-cone fuzing has a generatrix which is the vector sum of missile velocity, warhead velocity and the negative of target velocity.

Abstract: In missile guidance systems, knowledge of the target's flight policy and doctrine, along with an analysis of local topographic features, are used in a minimum commitment guidance policy. By assuming certain objectives of the target, paths may be defined by evaluating the degree of detection avoidance provided by the terrain adjacent to the various paths. To maximize the probability of intercept, a missile may be guided in a direction covering the most likely of these paths for periods while the target is hidden. The paths are then reevaluated each time the target is detected. For highly maneuverable targets that are capable of executing violent changes in direction and speed, the topography-aided guidance system maximizes the probability that the target can escape the missile intercept envelope.

Abstract: A device for seeking and tracking targets from airborne missiles, which comprises one or two optical sensing units, each comprising a sensor barrel covered by a dome, a detector, drive means for rotating the sensor barrel about two perpendicular axis, and a processor for processing the signals produced by the detector and guiding the missile accordingly. The drive means comprise two motors for imparting to the barrel a pitching and a rolling motion. To eliminate aerodynamic drag, each sensing unit may be displaceable between a position retracted within the missile envelope and an extended position, in which part of its dome extends from the missile envelope. When two sensing units are provided, a target is tracked by operating only one of them, and when the target moves out of its field-of-regard, deactivating it and activating the other unit to continue tracking the target.

Abstract: The invention relates to a window for use in a supersonic or hypersonic target-tracking missile, the window being transparent to electromagnetic radiation. The window consist of several window layers which support each other and which are commonly supported, wherein the materials, the thickness and the arrangement of said window layers are selected to reduce mechanical stresses due to temperature during supersonic or hypersonic flight as compared to a continuously homogeneous window. In one embodiment the window layers are fixedly interconnected with their surfaces facing each other and consist of materials having different thermal coefficients of dilatation such that, with the temperature gradient occurring in said window during supersonic or hypersonic flight, substantially identical thermal dilatations are achieved in each of said window layers.

Abstract: A detector assembly which includes an electrically conductive, two-piece, molded plastic housing including a relatively rigid bulkhead portion having a groove and a second dome portion having a sidewall extending over an adjacent bulkhead portion. The dome portion has a plurality of relatively flexible tabs, a part of each tab extending into the groove and making mechanical contact with the bulkhead portion via the groove to provide a press fit therebetween. An electrically conductive barrel is disposed within the housing and is electrically connected via an electrically conductive o-ring to the bulkhead to form an electrically shielded chamber within the housing in conjunction with the bulkhead and the dome portions. Equipment to be shielded is disposed within the chamber and is secured to the barrel.

Abstract: An aircraft missile vulnerability reduction system based on missile hit acceptance whereby a targeted aircraft's most critical components are protected by a preprogrammed, missile-attracting infrared decoy strategically positioned on a sacrificial portion of the aircraft's structure. The decoy is optimally located based on vulnerability analyses and includes multiple modes of operation that configure to instantaneous survivability needs. The system is capable of providing aircraft survivability against shoulder launched man-portable air defense systems missiles during low-level mission flight scenarios.

Abstract: The invention provides a method and apparatus for guiding a weapon to a target using an optical seeker having dual semi-active laser (SAL) and laser radar (LADAR) modes of operation. The dual mode seeker incorporates a laser light source, an optical package including a quadrant detector for operating in SAL mode and a LADAR receiver for operating in LADAR mode. The seeker further includes a high speed scanning mirror for switching between modes to guide the weapon to the target. The method for guiding a weapon to a target includes receiving radiation from the target and tracking the radiation to guide the weapon; monitoring the detected radiation such that if the radiation falls below a predetermined level, a laser system on-board the weapon continues guiding the weapon by generating a laser beam; reflecting the laser beam off the target so that the reflected laser radiation is received from the target to track the radiation and guide the weapon to the target.

Abstract: An imaging self-referencing target tracker (10) for a laser weapon (12). The weapon generates a first beam of radiation (14) that engages a target (16) to form a beam hit spot (20) thereon. In a first embodiment, a target illuminator (22) (variant 1) illuminates the target with a second beam of radiation (23a). An optics subsystem (30) receives and separately images the first and second beams (23b, 24) of radiation. In a second embodiment, a blocking filter (40) is implemented rather than an illumination laser to pass only radiation at the target wavelength, thereby ensuring that the first and second beams of radiation are separately imaged. A controller (32) is programmed to steer the first and second beams of radiation to the desired target aim point (18) in response to information from the imaged first and second beams of radiation.

Abstract: Provided is a compact, low-cost, lightweight, man-packable weapon system for engaging static and slowly maneuvering targets. In one embodiment, it may incorporate in its own backpack a compact launcher and multiple compact missiles, each weighing less than five pounds, for carry on a soldier's back. The missile itself uses a strapped-down acquisition and tracking sensor electrically connected to a simplified guidance system interfaced with an aero-control section capable of altering the flight path of the missile to a target. A solid-propellant rocket motor provides sufficient power to propel the missile at a predetermined limited speed and over a pre-determined limited distance that enables the proper operation of the simplified guidance system. A method for deploying a man-packable weapon system is disclosed also.

Abstract: A large (10's of meters) aperture space telescope including two separate spacecraft—an optical primary objective lens functioning as a magnifying glass and an optical secondary functioning as an eyepiece. The spacecraft are spaced up to several kilometers apart with the eyepiece directly behind the magnifying glass “aiming” at an intended target with their relative orientation determining the optical axis of the telescope and hence the targets being observed. The objective lens includes a very large-aperture, very-thin-membrane, diffractive lens, e.g., a Fresnel lens, which intercepts incoming light over its full aperture and focuses it towards the eyepiece. The eyepiece has a much smaller, meter-scale aperture and is designed to move along the focal surface of the objective lens, gathering up the incoming light and converting it to high quality images.

Abstract: A programmable optical system that dynamically corrects or induces aberrations into the optical path of a missile seeker. The system is dynamic in that the amount and type of aberration may be changed while the missile is in flight. The dynamic correction is accomplished by means of deformations applied to a low-mass mirror or mirrors in the optical path of the missile seeker. The missile includes an aspheric dome, and the optical system is dynamically compensated for aberrations introduced by the dome as the seeker system is moved through the field of regard.

Abstract: A biaxially rotational structure for a planar antenna comprises a biaxial base having a vertical direction and a horizontal direction, a vertical shaft assembly disposed at the vertical direction of the biaxial base, the vertical shaft assembly has a rotation limiting member; a support frame pivotally mounted on the vertical shaft assembly, the support frame having a stopper extending downwardly in a manner that the rotation limiting member limits the stopper to rotate within one turn with respect to the vertical shaft assembly; a first resilient member disposed between the vertical shaft assembly and the support frame for exerting a pressing force on the support frame; a horizontal shaft assembly disposed at the horizontal direction; and a second resilient member disposed between the horizontal shaft assembly and the biaxial base for exerting a friction force therebetween.

Abstract: A multi-color, multi-pulse laser target designator is disclosed in which the target is illuminated with pulses of preselected colors and interpulse spacings so as to uniquely identify the target. Inter-pulse spacing may be varied down to an arbitarily small spacing by virtue of the use of pulses of differing colors, thereby increasing countermeasure resistance due to the difficulty of a target detecting and duplicating inter-pulse spacing. Pulse elongation is provided in one embodiment to provide prolonged illumination of the target so as to permit increased homing accuracy for optically guided weapons.

Abstract: An infrared seeker head for target tracking missiles has a main detector and an imaging optical system generating an image of a field of view on the main detector. The field of view contains a target such as an enemy aircraft. The missile is guided to the target in accordance with signals from the main detector. The target, if attacked by the missile, emits high-intensity laser radiation towards the missile as a counter-measure. This is to disturb the operation of the seeker head by dazzling or even destroying the main detector. The seeker head contains a device for defending against such disturbances. Various types of such defending devices are described. Incident light is deviated from the main detector. A second-quadrant-detector of reduced sensitivity guides the missile along the disturbing laser beam. Another embodiment uses attenuating optical elements in front of the main detector under the control of one or more second detectors.

Abstract: A system using a scanning mirror for scanning the field of view of an optical objective. The scanning mirror is mounted for rotation about an axis transverse to the major plane of the mirror and for pivotal oscillation about an axis lying substantially within the major plane of the mirror. The combined effect of rotation and pivotal movement is to scan the field of view of an optical objective. The scanning angle and other significant characteristics of the scan pattern may be changed as desired by means external to the system, producing, for example, a rosette, spiral, or circular scanned pattern with or without dimensional changes in the total scanned field of view. Such a scanning system may be embodied in seeker systems used for the guidance of radiation-seeking missiles operating in single or multiple regions of the electromagnetic spectrum.

Abstract: A method for assigning a target within a cluster of targets to a specific one of a plurality N of weapons launched from M airplanes is provided. The method includes providing the specific weapon with an index (m,n) based on the weapon bay n and the airplane m from which it is to be launched, receiving the central location and determining the shape of the cluster; dividing the cluster shape into N sub-clusters wherein each sub-cluster n has M sectors m, determining the center of gravity of each sector; associating the specific weapon with the sector having index (m,n); and assigning a target from among the targets in the associated sector to the specific weapon.

Abstract: A missile includes a fuselage with a roll axis and a nod axis perpendicular to the roll axis, and a conformal window mounted to a forward-facing end of the fuselage. There is a sensor system with a field of regard through the window and a line of sight, and a sensor system pointing mechanism affixed to the airframe and upon which the sensor system is supported. The sensor system pointing mechanism includes a gimbal structure having a first degree of rotational freedom about the roll axis and a second degree of rotational freedom about the nod axis, and a linear translational mechanism connected to the sensor system. The linear translational mechanism is operable to translate the sensor system away from the window with increasing angular deviation of the line of sight of the sensor system from the roll axis. Preferably, the translational mechanism is a slider-crank mechanism.

Abstract: The invention relates to a seeker head for target tracking missiles having an image resolving seeker being gimbal suspended in a seeker gimbal assembly and adapted to be aligned to a target by target deviation signals, and inertial sensors. A virtual inertially stabilized reference coordinate system is adapted to be defined from signals from the image resolving seeker and from the seeker gimbal assembly, said stabilized reference coordinate system having an axis aligned to said target. The stabilized reference coordinate system is adapted to be aligned to predicted target positions in case of deterioration of the tracking function of the seeker to the target in accordance with the line of sight information (e.g. direction, angular rate, angular acceleration) of the reference coordinate system then present. The seeker is adapted to be aligned to the axis of the reference coordinate system when the deterioration ceases, the signals from the seeker taking over the tracking function of the seeker again.

Abstract: A missile guidance system with a fixed body missile seeker having an adjustable look angle. The missile seeker has a fixed camera whose look angle is adjustable to keep a moving target within the field of view of the camera. The target is tracked by a tracker to generate target angle and line of sight rate signals. The target angle signal is input to pointing angle adjustment apparatus which adjusts the look angle of the camera. The pointing angle adjustment apparatus may comprise a stepper motor that controls the angular position of a gimbal on which the camera is mounted. Alternatively, the pointing angle adjustment apparatus may comprise one or more stepper motors that control an adjustable zoom lens or a plurality of optical wedges, respectively. A body angular rate output signal of a body-fixed inertial measurement system is summed with the line of sight rate signals from the tracker to determine the inertial line of sight rate of the moving target.

Abstract: A photoconductive detector (3) comprises a single continuous photoconductive strip consisting of two interleaved photoconductive spiral paths (1, 2) separated by much thinner gaps (5, 6). The two spiral paths (1, 2) have the same central point (19). The detector (3) is substantially planar and has the overall shape of roughly a circle (10). A circular band (4) of incident radiation (16) crosses the gaps (5, 6) in a nearly parallel fashion, rather than nearly perpendicularly as in the prior art, lessening unwanted modulations of the detected signal. The terminal (11) to terminal (12) resistance of the detector (3) is increased to the point where, when the photodetector (3) is made of the preferred HgCdTe, simple thermo-electric coolers are sufficient to enable use of the detector (3) as an infrared detector (3) in a heat-seeking missile (17).