System and method for tracking and locating a person, animal, or machine

An inertial navigation system comprising:

• an originator device including a first inertial measurement unit, a first processing unit, and a plurality of originator antennas including at least a first originator antenna and a second originator antenna;
• and
• a transponder device including a second inertial measurement unit, a second processing unit, and a second plurality of antennas including at least a first transponder antenna and a second transponder antenna;
• said first inertial measurement unit and said second inertial measurement unit are configured to transmit IMU data to at least one of said first processing unit and said second processing unit, and at least one of said first processing unit and said second processing unit receiving said IMU data is configured to estimate a position using said IMU data;
• said first originator antenna and said first transponder antenna are separated by a first distance;
• said first originator antenna and said second transponder antenna are separated by a second distance;
• said first originator antenna is configured to transmit a first wireless signal to said first transponder antenna and said second transponder antenna;
• said first transponder antenna is configured to transmit a second wireless signal to said first originator antenna;
• said first transponder antenna and said second transponder antenna are configured to receive said first wireless signal from said first originator antenna;
• said first originator antenna is configured to receive said second wireless signal from said first transponder antenna;
• at least one of said first processing unit and said second processing unit is configured to calculate a value related to said first distance;
• at least one of said first processing unit and said second processing unit is configured to calculate a value related to said second distance;
• and
• at least one of said first processing unit and said second processing unit is configured to update an estimate of said position using said value related to said first distance and said value related to said second distance.