Patent ID: 9374214
Filing Date: 2016-06-21
CPC Classification: H04J,H04L

Claim Text:
1. A communication apparatus configured for communicating with a master apparatus generating events at a constant time interval via a network, the communication apparatus comprising: a clock including a crystal oscillator; an event generator, implemented by a computer, configured to generate an event based on the clock in accordance with event interval information specifying a time interval for event generation; hardware storage configured to store a first timestamp representing a time when the event is generated in the event generator; a receiver configured to receive, from the master apparatus, a frame containing a second timestamp representing a time of an event generated in the master apparatus; an event interval corrector, implemented by the computer, configured to correct the event interval information to make a timing of event generation in the event generator closer to a timing of event generation in the master apparatus based on the first timestamp, the second timestamp, and a pre-acquired time difference between the clock and the master apparatus; and a timing difference calculator, implemented by the computer, configured to calculate (i) a first timing difference that is a timing difference between the event generated in the master apparatus and the event generated in the event generator based on the first timestamp, the second timestamp, and the time difference and (ii) a second timing difference that is a timing difference between the event generated in the event generator and an event already generated or to be generated in the master apparatus temporally closest to the event generated in the event generator based on the first timing difference and a value of the constant time interval, wherein the event interval corrector corrects the event interval information based on the second timing difference.