Coordinate transformation system

An aircraft-based missile guidance and tracking system, comprising:

• gimbal-mounted sight unit means for aiming at a missile target and for detecting a tracking signal generated by a missile in flight;
• means for measuring aircraft and missile position signals;
• means for inputting commands to said system, said means for inputting commands in communication with said sight unit means and said signals measuring means;
• means for generating guidance signals for guiding said missile to said missile target including;
• position sensors for generating analog aircraft and missile position signals;
• analog to digital converter means for converting said analog position signals into digital signals;
• a microprocessor connected to said analog to digital converter for computing a roll angle around a line of sight of said display,
• said microprocessor adjusting said guidance signals to compensate for said roll angle;
• and
• digital to analog converter means for converting said adjusted guidance signals to analog form, and for outputting said adjusted analog signals to said guidance signal generating means for computation of said guidance signals.

In an aircraft-based missile guidance and tracking system, including a sight unit mounted on a gimbal for aiming at a missile target and for detecting a tracking signal generated by a missile in flight, and a mechanism for generating guidance signals for guiding said missile to said target, a method for digitally transforming aircraft coordinates to compensate for aircraft movement subsequent to launching of said missile, comprising the steps of:

• sensing aircraft and missile position signals;
• converting analog position signals into digital signals;
• computing a roll angle and change in roll angle around a line of sight of said sight unit from said digital position signals;
• adjusting said digital position signals to compensate for said roll angle;
• converting said adjusted position signals to analog form;
• and
• outputting said adjusted analog position signals to said system for computation of said guidance signals.

An aircraft-based missile guidance and tracking system including a sight unit for aiming at a missile target and for detecting a tracking signal generated by a missile in flight, and a mechanism for generating guidance signals for guiding said missile to said target, comprising:

• position sensors for measuring a first set of analog aircraft and missile position signals;
• first analog to digital converter means having a plurality of inputs connected to said position sensors and a plurality of outputs, said first analog to digital converter means for converting said analog position signals into digital signals;
• a microprocessor for performing digital coordinate transformation functions, said microprocessor having both an address bus and a data bus;
• a multiplexer having a plurality of inputs and an output, said inputs of said multiplexer receiving a second set of analog aircraft and missile position signals, said multiplexer being connected to address multiplexer through said address bus;
• second analog to digital converter means connected between said output of said multiplexer and said data bus of said microprocessor, said second analog to digital converter means operative for converting said second set of position analog signals into digital signals;
• said microprocessor computing roll angle around line of sight from said first set of position signals, said microprocessor transforming said digital signals to adjust said digital signals for said roll angle around said line of sight;
• and
• a digital to analog converter for converting said adjusted second set of digital signals into analog signals for further processing by said missile guidance and tracking system.