Patent ID: 7847734
Filing Date: 2010-12-07
Classification: G01S

Abstract:
1. A method of multilaterating the position of a target, comprising the steps of: deploying a plurality of time synchronized or non-synchronized transceiver units in a network, each of the plurality of time synchronized or non-synchronized transceiver units in the network communicating with other transceiver units and communicating with a central processor; using one of a probe operation or a U-probe operation to determine propagation delay measurements between at least a first transceiver unit and each transceiver unit of the plurality of time synchronized or non-synchronized transceiver units within a coverage area of the first transceiver unit; determining calibration values for a local clock of the first transceiver unit relative to each transceiver unit of the plurality of time synchronized or non-synchronized transceiver units within a coverage area of the first transceiver unit; determining a position of each transceiver unit relative to the first transceiver unit; receiving a target signal from the target at three or more transceiver units of the plurality or time synchronized or non-synchronized transceiver units; determining a time of arrival for the target signal at each transceiver unit receiving the target signal based on at least the calibration value for the tranceivers local clock and the clocks of other transceiver units that also receive the target signal; determining a time difference of arrival of the target signal using the time of arrival measured between each pair of transceiver units receiving the target signal; and using the corrected time difference of arrival and the position of the transceiver units receiving the target signal to determine the position of the target by multilateration.