Patent ID: 11863146
Assignee: WHELEN ENGINEERING COMPANY, INC.
Field: Control (Instruments)
Classification: CPC G  H | IPC H

Claim 19:
20. A synchronization method, comprising:
generating, by a first node including a first emergency sound generator, a first tone signal having a voltage level;
outputting, by the first node, the generated first tone signal to a second node;
generating, by the first node, a first sound wave based on the first tone signal;
receiving, by the second node including a second emergency sound generator, the first tone signal from the first node; and
generating, by the second node, a second sound wave based on the received first tone signal,
wherein the first sound wave is synchronized with the second sound wave in tone and phase;
wherein the one or more processors are further configured to synchronize the first sound wave tone and the second sound wave tone one to another by setting a phase offset between the first sound wave tone and the second sound wave tone to be the same;
wherein to synchronize the first sound wave tone and the second sound wave tone, the first node and the second node each determine a common global time based on one or more synch messages transmitted from a main node;
wherein the first node is further configured to:
receive a first time at which the main node transmits a first synch message including the first time;
determine a second time at which the first node receives the first synch message;
determine a difference between the first time and the second time;
receive a third time at which the main node transmits a second synch message including the third time;
determine a fourth time at which the first node receives the second synch message; and
determine the global time by adding the difference to the third time.