Location system adapted for use in multipath environments

The location system of claim further comprising:

• at least one calibration transmitter, positioned at a known location, for transmitting calibration transmissions receivable by each of the receivers;
• each receiver being responsive to a calibration transmission for providing a corresponding calibration TOA detection packet, including the associated time-of-arrival TOA count, to the location processor;
• and
• the location processor determines calibration coefficients from the calibration TOA detection packets and the known locations of the receivers, and uses those coefficients to calibrate location computations from TOA-detection packets associated with TAG transmissions.

A location system for locating objects within a tracking environment using area-detection by receivers that receive electromagnetic transmissions from assigned areas, comprising:

• for each object, a TAG transmitter for transmitting, at selected intervals, TAG transmissions that include a unique TAG ID;
• an array of receivers distributed within the tracking area, with each receiver being configured to receive TAG transmissions from an assigned area of a predetermined size;
• each receiver including a data communications controller responsive to the receipt of a TAG transmission for providing a corresponding area-detection packet that includes the received TAG ID;
• and
• a location processor for receiving the area-detection packets, and for determining the location of each TAG, and its associated object, based on the identity of the receiver receiving the TAG transmissions for that TAG.

A method for locating of objects within a tracking environment using time-of-arrival differentiation for electromagnetic transmissions received at multiple receivers, comprising the steps:

• for each object, transmitting, at selected intervals, TAG transmissions that include a unique TAG ID;
• providing an array of receivers distributed within the tracking environment such that a TAG transmission is received by at least three receivers;
• in response to the arrival of a TAG transmission at a receiver, providing a TOA count corresponding to the time-of-arrival of the most direct path for such TAG transmission, with the TOA count being synchronized to a system synchronization clock provided to each receiver;
• in response to the receipt of a TAG transmission, providing a corresponding TOA-detection packet that includes the associated TAG ID and TOA count;
• and
• using the TOA-detection packets, determining the location of each TAG, and its associated object, from at least three corresponding TOA-detection packets received from different receivers.

A method of locating objects within a tracking environment using area-detection by receivers that receive electromagnetic transmissions from assigned areas, comprising:

• for each object, providing a TAG transmitter for transmitting, at selected intervals, TAG transmissions that include a unique TAG ID;
• providing an array of receivers distributed within the tracking area, with each receiver being configured to receive TAG transmissions from an assigned area of a predetermined size;
• each receiver being responsive to the receipt of a TAG transmission for providing a corresponding area-detection packet that includes the received TAG ID;
• and
• determining the location of each TAG, and its associated object, based on the identity of the receiver receiving the TAG transmissions for that TAG as represented by the area-detection packet provided by such receiver that received the TAG transmissions.