US 11,856,484 B2
Systems and methods for precise radio frequency localization of wireless nodes using time difference of arrival and decoupling in time synchronizing of the wireless nodes from ranging
Mark Bilstad, Los Altos, CA (US); Tommi Ylamurto, Los Gatos, CA (US); and Manu Seth, Berkeley, CA (US)
Assigned to ZaiNar, Inc., Redwood City, CA (US)
Filed by ZaiNar, Inc., Redwood City, CA (US)
Filed on Jul. 9, 2021, as Appl. No. 17/371,963.
Prior Publication US 2023/0011851 A1, Jan. 12, 2023
Int. Cl. H04W 4/029 (2018.01); H04W 64/00 (2009.01); H04W 56/00 (2009.01)
CPC H04W 4/029 (2018.02) [H04W 56/001 (2013.01); H04W 64/00 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An asynchronous wireless system for localization of nodes in a wireless network architecture, comprising:
first wireless node and a second wireless nodes each:
having a known location; and
including a wireless device with one or more processing units and radio frequency circuitry for transmitting and receiving communications in the wireless network architecture; and
a third wireless node and a fifth wireless node each:
having an unknown location; and
including a wireless device with radio frequency circuitry to enable communications with the first wireless node and the second wireless node in the wireless network architecture; and
wherein the first wireless node is configured to:
receive a first communication from the third wireless node;
determine time difference of arrival of the first communication at the first wireless node and the second wireless node;
identify a relative or absolute position of the third wireless node based on the time difference of arrival;
send a second communication with a synchronization packet to the second wireless node; and
synchronize the first wireless node and the second wireless node based on the second communication to identify a time difference between a first clock of the first wireless node and a second clock of the second wireless node, the synchronization of the first wireless node and the second wireless node being independent and decoupled from the first communication; and
receive packets from the third wireless node and the fifth wireless node in parallel via a first radio frequency channel and a second radio frequency channel, the first radio frequency channel relaying signals from the third wireless node and the second radio frequency channel relaying signal from the fifth wireless node.