US 11,811,503 B2
Method and apparatus for switching clock sources
Yao Peng, Beijing (CN); Jun Wang, Beijing (CN); and Daiying Liu, Beijing (CN)
Assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL), Stockholm (SE)
Appl. No. 17/606,799
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Apr. 29, 2019, PCT No. PCT/CN2019/084888
§ 371(c)(1), (2) Date Oct. 27, 2021,
PCT Pub. No. WO2020/220177, PCT Pub. Date Nov. 5, 2020.
Prior Publication US 2022/0209882 A1, Jun. 30, 2022
Int. Cl. H04J 3/06 (2006.01)
CPC H04J 3/0667 (2013.01) [H04J 3/0617 (2013.01); H04J 3/0629 (2013.01); H04J 3/0688 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A method for switching clock sources, the method comprising:
monitoring Precision Time Protocol (PTP) packets received via a first PTP port connected to a new grandmaster (GM);
calculating a frequency and a phase for the first PTP port based on the received PTP packets;
based on the calculated frequency and phase for the first PTP port, determining whether to add the first PTP port to a list of candidate ports; and
selecting a slave port using the list of candidate ports.