| CPC H04W 4/029 (2018.02) [G01S 5/021 (2013.01); G01S 5/0284 (2013.01); G01S 5/10 (2013.01); H04L 5/0007 (2013.01); H04L 5/0051 (2013.01); H04L 5/0053 (2013.01); H04W 56/001 (2013.01); H04W 64/00 (2013.01)] | 11 Claims |

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1. A method for calculating a location of a user device comprising:
for a first transceiver in a set of transceivers:
accessing a first time-of-arrival of a first multicarrier uplink signal, transmitted from the user device, at the first transceiver, the first time-of-arrival calculated by:
receiving the first multicarrier uplink signal comprising a first subcarrier uplink signal for a first subcarrier frequency in a set of subcarrier frequencies;
calculating a first phase difference between the subcarrier uplink signal and a first corresponding subcarrier reference signal;
calculating a first phase offset based on the first subcarrier frequency and a first calibration function for the first transceiver;
calculating a first adjusted phase difference for the first multicarrier uplink signal based on the first phase difference and the first phase offset; and
calculating the first time-of-arrival of the first multicarrier uplink signal based on the first adjusted phase difference for the first multicarrier uplink signal; and
calculating a first time-differences-of-arrival based on the first time-of-arrival of the first multicarrier uplink signal; and
calculating an uplink location estimate of the user device based on the first time-differences-of-arrival and a location of each transceiver in the set of transceivers.
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