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:
Nov. 08, 2011
Filed:
May. 20, 2004
Moo Ryong Jeong, San Jose, CA (US);
Fujio Watanabe, Sunnyvale, CA (US);
Toshiro Kawahara, Saratoga, CA (US);
Moo Ryong Jeong, San Jose, CA (US);
Fujio Watanabe, Sunnyvale, CA (US);
Toshiro Kawahara, Saratoga, CA (US);
NTT DoCoMo, Inc., Tokyo, JP;
Abstract
Active scanning method in a wireless network for fast determining available access points () using inter-AP (Access Point) communication is described. In the scanning method, a mobile station () sends Probe Request for Proxy frame to the current AP () serving the mobile station (). In response to the Probe Request for Proxy frame, the current AP () send Proxy Probe Request packet to the appropriate APs (). In response to the Proxy Probe Request packet, the neighbor APs () send Probe Response frame to the mobile station () on its operating channel. Since the mobile station () moves to the channel being examined after sending the Probe Request for Proxy frame, it receives the Probe Response frame if it is in the coverage area of the neighbor AP (). The content of Probe Response frame provides the mobile station () with the information to be used in handoff decision and network join procedures. Thus, the mobile station () neither has to move to the channel to be examined nor send Probe Request frame on that channel. This enables active scan to be initiated even when the neighbor AP () is operating in PCF (Point Coordination Function) and the network is in CFP (Contention Free Period), during which unassociated mobile stations (including the scanning mobile station) cannot send packets.