US 11,943,688 B2
Synchronization between devices in emergency vehicles
Caleb Garrett, Chester, CT (US); and Brandon Conlon, Chester, CT (US)
Assigned to WHELEN ENGINEERING COMPANY, INC., Chester, CT (US)
Filed by WHELEN ENGINEERING COMPANY, INC., Chester, CT (US)
Filed on Aug. 3, 2020, as Appl. No. 16/983,577.
Application 16/983,577 is a continuation in part of application No. 16/815,988, filed on Mar. 11, 2020.
Claims priority of provisional application 62/884,871, filed on Aug. 9, 2019.
Prior Publication US 2021/0043081 A1, Feb. 11, 2021
Int. Cl. H04W 4/46 (2018.01); H04L 12/40 (2006.01)
CPC H04W 4/46 (2018.02) [H04L 12/40 (2013.01); H04L 2012/40215 (2013.01); H04L 2012/40273 (2013.01)] 29 Claims
OG exemplary drawing
 
1. A synchronization system, comprising:
a first node configured to:
transmit a first synchronization message;
determine a first time at which the first synchronization message is transmitted;
transmit a second synchronization message containing a tx timestamp corresponding to the first time;
a second node configured to:
receive the first synchronization message from the first node;
determine a second time at which the first synchronization message is received and store a rx timestamp corresponding the second time;
receive the second synchronization message from the first node;
determine a current local time at which the second synchronization message is received;
read the tx timestamp in the second synchronization message;
adjust the current local time of the second node by adding a difference between the tx timestamp and the rx timestamp to the current local time; and
setting the adjusted current local time as a global time.