A seeker system for a missile having a housing with a predetermined field-of-regard the system including an image detector adapted to be fixedly mounted to the housing having a predetermined number of pixels, an optical system fixedly mounted to the housing for scanning said predetermined field-of-regard ahead of the nose for focusing images in successive image frames onto the image detector, an image reader for reading image data from the image detector corresponding to each of the successive image frames, a display for displaying the image data of the successive image frames, a selector for selecting a displayed target from the field-of-regard, a comparator for comparing the image data of successive image frames, and a tracker for tracking the selected target by setting a course of the missile in a direction toward the target, a discriminator responsive to the compared frames for discriminating between a first deviation below a predetermined amount and a second deviation above the predetermined amount, a stabilizer responsive to the first deviation for stabilizing the display of the images, and a missile controller responsive to the second deviation for repositioning the missile to a desired course.
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. The inertial line of sight rate is driven to zero or a low fixed value by a control system to accurately track a target. The control system and missile dynamics generate a body angle signal that is input to a difference circuit along with a camera pointing angle signal output by the pointing angle adjustment apparatus. The difference circuit generates a desired camera pointing angle that is input to the pointing angle adjustment apparatus to point the camera at the target.
A system and method for assessing the probability of detection of a target of a hyperspectral sensing system. The system is adapted to calculate the probability of detection of targets based on various sensor parameters, atmospheric conditions, and a specified combination of targets and backgrounds for a given false alarm rate. The system may be executed, for example, on an IBM compatible PC to allow the user to optimize the hyperspectral sensor and subsequent signal processing to a particular set of backgrounds and targets. The sensor models, atmospheric models and target and background profiles are initially applied to the system in the form of the databases. As such, the system enables the user to select among the various parameters to optimize a hyperspectral sensor and the subsequent signal processing for a particular set of parameters.
A method and system of image modulation detection of an aircraft exhaust plume by time sequence differentiation is provided. The method comprises the steps of forming two sequential images of the field of view in which an exhaust plume to be detected is located, and forming a differential image from the sequential images showing components of the aircraft's exhaust plume that are modulating at a rate greater than the frame rate of the detection system. The nonmodulating components such as the sky hills, and even the missile body are eliminated from the differential image. Only the plume remains and only the plume is detected. Therefore there is not false alarm note. Each image is formed by a plurality of pixels, wherein each pixel images a portion of the field of view. A value is assigned to each pixel in each of the sequential images that corresponds to one or more characteristics of the pixel. The value of each pixel in one sequential image is subtracted from the value of the corresponding pixel in the other sequential image to produce a value for a resultant pixel. The differential image is formed by imaging the resultant pixels that have a non-zero value, wherein the differential image shows components of the aircraft's exhaust plume that are modulating at a rate greater than the frame rate of the detection system.
A missile weapons system with a homing head optical system and an alignment processor, in which the visual field of the homing head is adjusted to the size of the target by handing over the target marking frame size to the homing head, which is equipped with a zoom lens, and the effect of parallax on the correlation is eliminated.
A method for determining the trajectory of a projectile on a ballistic trajectory includes creating a sequence of images of the projectile using a passive image sensor located at an observer; determining the time the projectile started on its trajectory; determining relative positions of the projectile's launch point, the observer, and an expected impact point; ballistically modelling the projectile; and tracking the projectile through the sequence of images using a track before detect algorithm.
