System and method for hybrid location in an LTE network

摘要

A system and method for estimating a location of a wireless device receiving signals from plural nodes of a communications network. A wireless device may be directed to transmit a first signal having one or more predetermined parameters. At one or more location measurement units (“LMU”) an uplink time of arrival (“TOA”) measurement between the wireless device and one or more of the plural nodes or LMUs may be determined as a function of the first signal transmitted from the wireless device. Downlink signal measurements of signals received by the wireless device may be collected, and a location of the wireless device determined as a function of the uplink TOA measurements and the collected downlink signal measurements.

主权项

1. A method for estimating a location of a wireless device receiving signals from plural nodes of a communications network, the method comprising:
(a) directing a wireless device to transmit a first signal having one or more predetermined parameters; (b) transmitting the first signal by the wireless device; (c) determining at one or more location measurement units (“LMU”) an uplink time of arrival (“TOA”) measurement between the wireless device and one or more of the plural nodes or LMUs as a function of the transmitted first; (d) collecting downlink signal measurements of signals received by the wireless device; and (e) determining a location of the wireless device as a function of the uplink TOA measurements and the collected downlink signal measurements, wherein determining the location of the wireless device comprises:
using the uplink TOA measurements and a timing advance measurement to derive a plurality of uplink range rings to the wireless device, each range ring associated with a different node in the plural nodes and at least one uplink hyperbola based on the time difference between the uplink TOA measurements at the different plural nodes;using the collected downlink signal measurements to derive a plurality of downlink range rings to the wireless device from the plural nodes and at least one downlink hyperbola based on the time difference between the signal measurements for signals received from the different plural nodes; anddetermining the location of the wireless device based on a combination of range rings and hyperbolas in the plurality of uplink range rings, the plurality of downlink range rings, the at least one uplink hyperbola, and the at least one downlink hyperbola.