The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 30, 2000
Filed:
May. 28, 1997
Edward W Geiger, San Marten, CA (US);
Stanley L Fickes, San Jose, CA (US);
Richard W Mincher, San Jose, CA (US);
Jeffrey L Mullins, San Jose, CA (US);
Apple Computer, Inc., Cupertino, CA (US);
Abstract
Aspects for achieving and utilizing synchronization among end stations in a wireless local area network (WLAN) are provided. In a method aspect, the method includes receiving a packet with a time synchronization field value from a first end station in a second end station of a communication group. The method further includes comparing upon receipt of the packet the time synchronization field value with a local time value in the second end station to determine whether the local time value requires updating to maintain synchronization between the first and second end stations. The comparing further determines whether a difference between the time synchronization field value and the local time value is greater than zero, and when the difference is greater than zero, the local time value is updated to the time synchronization field value. In a system aspect, the system includes at least two end stations, wherein each of the at least two end stations further includes a local clock unit, and a transmit/receive control unit coupled to the local clock unit. A time synchronization field register in the transmit/receive control unit stores a value of the local clock unit, with one of the at least two end stations comparing a time synchronization field register value of a packet upon receipt from another of the at least two end stations with a value of the local clock unit to determine whether updating of the local clock unit is necessary.