System and method for determining attitude using spatial shift key (SSK) modulation signatures

A method for determining attitude, the method comprising:

• a) transmitting a signal through a radiating means which moves through three-dimensional space with a predetermined movement, such that a cyclic Doppler is superimposed upon the transmitted signal;
• b) receiving said transmitted signal at a receiving means which moves through three-dimensional space with a predetermined movement, such that a cyclic Doppler is superimposed upon the received signal;
• c) analysing said cyclic Doppler superimposed upon said received signal to determine a Doppler pattern;
• and
• d) determining the attitude of said receiving means by matching said determined Doppler pattern to pre-defined Doppler patterns associated with known relative attitudes of said radiating means and said receiving means.

A method for determining attitude, the method comprising:

• a) transmitting a plurality of signals from a plurality of spatially distributed transmission means configured with at least one or more radiating means, said radiating means configured to move through three-dimensional space with identical predetermined movement, with each of said plurality of signals assigned to one of said radiating means, such that an identical cyclic Doppler is superimposed upon each transmitted signal;
• b) receiving said plurality of transmitted signal at a receiving means which moves through three-dimensional space with a predetermined movement, such that a cyclic Doppler is superimposed upon the received signal;
• c) adjusting said predetermined movement of said receiving means to bring said cyclic Doppler superimposed upon said received signal signals to a predetermined value such that said receiving means slews into alignment with said radiating means;
• and
• d) determining the attitude of said receiving means based upon the required adjustment to said predetermined movement of said receiving means.

A method for determining the attitude of a mobile apparatus, the method comprising the steps of:

• a) transmitting a positioning signal through radiating means, said radiating means moving its phase centre through three-dimensional space with a predetermined movement at a predetermined interval, such that a first cyclic doppler is superimposed upon said positioning signal;
• b) receiving said positioning signal through receiving means, said receiving means moving its phase centre through three-dimensional space with a predetermined movement at a predetermined interval, such that a second cyclic doppler is observed by said receiving means;
• c) measuring a combined cyclic doppler observed by said receiving means, said combined cyclic doppler comprising said first cyclic doppler and said second cyclic doppler;
• d) adjusting said predetermined interval of said receiving means, such that said combined cyclic Doppler is minimised, said receiving means slews into alignment with said radiating means and said receiving means is brought into spatial correlation with said radiating means;
• e) determining the attitude of said mobile apparatus based on the required adjustment to said predetermined movement of said receiving means.

A method for determining the attitude of a mobile apparatus, the method comprising the steps of:

• a) transmitting a plurality of positioning signals through a plurality of radiating means, each of said plurality of radiating means moving its phase centre through three-dimensional space with a predetermined motion at a predetermined interval, such that a first cyclic doppler is superimposed upon each of said plurality of positioning signals;
• b) receiving said plurality of positioning signals through a plurality of receiving means, each of said plurality of receiving means moving its phase centre through three-dimensional space with a predetermined motion at a predetermined interval, such that a second cyclic doppler is observed by each of said plurality of receiving means;
• c) measuring a plurality of combined cyclic doppler observed by said plurality of receiving means, each of said combined cyclic doppler comprising a first cyclic doppler superimposed upon one of said plurality of positioning signals and a second cyclic doppler observed by one of said plurality of receiving means;
• d) differencing said first cyclic doppler from each of said plurality of positioning signals with said second cyclic doppler observed by each of said plurality of receiving means;
• e) adjusting the predetermined motion of the respective phase centres of said plurality of receiving means to match said predetermined motion of the respective phase centres of said plurality of radiating means, such that said receiving means slews into alignment with said radiating means thereby to minimise said plurality of combined cyclic Doppler;
• f) determining the attitude of said plurality of said mobile apparatus based on the required adjustment to said predetermined motion of said receiving means.

A method for determining the attitude of a mobile apparatus, the method comprising the steps of:

• a) transmitting a positioning signal through radiating means, said radiating means moving its phase centre through three-dimensional space with a predetermined movement at a predetermined interval, such that a first cyclic doppler is superimposed upon said positioning signal;
• b) receiving said positioning signal through receiving means, said receiving means moving its phase centre through three-dimensional space with a predetermined motion at a predetermined interval, such that a second cyclic doppler is observed by said receiving means;
• c) continuously measuring a combined cyclic doppler observed by said receiving means, said combined cyclic doppler comprising said first cyclic doppler and said second cyclic doppler;
• d) continuously matching said combined cyclic doppler with predetermined doppler patterns associated with said receiving means;
• e) determining the attitude of said receiving means based on said matched predetermined doppler patterns.