System and method for spatial location and tracking

A system for navigated medical procedures, comprising:

• at least one transmitter array, each of said at least one transmitter array comprising at least three first transmitters and at least one second transmitter that transmits at a higher speed that the first transmitters;
• at least one receiver array, each of said at least one receiver array comprising at least three first receivers that receive transmissions from said first transmitters and at least one second receiver that receives transmissions from said second transmitter;
• a display system that displays information;
• and
• a measurement system that controls said at least one transmitter array and said at least one receiver array to cause a sequence of transmissions by said second transmitter and all of said first transmitters, wherein in each transmission, said second transmitter and only one of said first transmitters transmit signals and the transmitted signals are received by said second receiver and all of said first receivers;
• said measurement system being configured to calculate distance measurements between each of said first transmitters and each of said first receivers based on time delays between reception of the signals transmitted in each transmission and a speed of sound;
• said measurement system being further configured to determine a three-dimensional location of at least one of said first transmitters relative to said first receivers from at least three calculated distance measurements between said first transmitter and said first receivers;
• whereby placement of said at least one transmitter array or said at least one receiver array on at least one object used in the medical procedure enables the three-dimensional location of the at least one object to be viewed on said display.