US Government As Represented by the Secretary of the Army

Robert L Sitton

Walter E Miller, Jr

Jimmy R Duke

George W Starkey

Dorwin L Kilbourn

Nicholas J Mangus, Jr

Anthony D Blackmon

Walter F Fountain

An improved automatic missile tracking and guidance system wherein a laund missile is guided along a line-of-sight maintained by the operator with the target. The position of an infrared source disposed on the missile is detected and guidance signals generated in accordance therewith to control the flight of the missile along the line-of-sight. The infrared source or beacon disposed on the missile comprises an array of semiconductor light emitting diodes. The solid state characteristics of the light emitting diodes provide heretofore unobtainable reliability over existing beacons. The beacon may be used to produce a modulated, high frequency, rectangular waveform, incoherent emission offering performance improvements including virtual immunity to optical countermeasures.

Light emitting diode beacons for command guidance missile track links

An optical tracking link in an automatic command to line-of-sight missile idance system improves the system efficiency and employs a reuseable light source. In tracking a missile during trajectory toward a target, short pulses of collimated light are transmitted from the launch site toward the missle. These light pulses are received by a missile optical receiver for guidance of the missile and are simultaneously reflected by a retrodirective prism on the missile. The reflected energy follows a path parallel to the incident wave and is thus directed back to the launch site. A missile tracker at the launch site responds to the reflective energy, measuring any deviation of the missile from a line-of-sight axis maintained between the launch site and a target. Guidance commands are transmitted toward the missile for maintaining the missile on the line-of-sight trajectory and containing correctional signals in response to any missile deviation. During intervals between return reflections, the missile tracker can be gated off. This greatly reduces background and jamming source reflections and signals, received by the tracker providing effective counter measures hardening of the system.

Range gated retroreflective missile guidance system

The optical attitude reference system provides missile attitude reference ing an optical beam in lieu of conventional gyroscopes. In the missile control systems autopilot, the system uses the properties of polarized light to determine missile roll angle relative to the beam transmitter reference axes at the launch site.

Optical attitude reference

An optical tracking link for a command guidance missile system employing l frequency modulation of the optical signal transmitted from the missile beacon. Dual frequency encoding of the missile tracking beacon improves beacon-tracker performance in the presence of countermeasures or false signals. A solid state, missile beacon within the missile housing transmits alternate bursts of optical energy of first and second high frequencies during alternate half cycles of a low frequency modulating signal therefor. The optical, modulated signal is received by an optical tracker at the missile launch site, completing a link between the missile and the launch site. A visual tracker at the launch site provides line-of-sight contact with a target being tracked. A guidance control for the missile responds to output signals from the missile and visual tracker to develop an error signal between the longitudinal, line-of-sight axis and the missile trajectory. Any deviation of the missile from a course of impact with the target causes an error signal to be transmitted to the missile for flight course correction. The solid state beacon includes first and second clocks each having a high frequency output therefrom, which is modulated by a low frequency and coupled through a power driver to a GaAs diode array, which generates an optical signal in response to a square wave input signal. This alternately modulated signal is received by a detector preamplifier of the optical tracker. A diode array in the detector is activated by the impinging optical signal and generates an electrical signal in response to the input wave. This signal is filtered to retrieve the two high frequencies and demodulated to extract the lf modulating wave from each frequency. This low frequency is then combined in a differential amplifier and interfaced with error detection equipment for generating a command guidance signal to the missile for attitude control thereof.

Growing community of inventors

Huntsville, AL, United States of America

Robert L Sitton