Title (en)

METHOD AND APPARATUS FOR RE-ACQUISITION AFTER LINK DISRUPTION IN AN OPTICAL WIRELESS LINK

Title (de)

VERFAHREN UND VORRICHTUNG ZUR NEUAQUISITION NACH EINER STRECKENUNTERBRECHUNG IN EINER OPTISCHEN DRAHTLOSEN STRECKE

Title (fr)

PROCEDE ET APPAREIL DE REAQUISITION D'ALIGNEMENT APRES INTERRUPTION DE LIAISON DANS UNE LIAISON OPTIQUE SANS FIL

Publication

EP 1386425 A4 20071107 (EN)

Application

EP 02764279 A 20020419

Priority

• US 0212571 W 20020419
• US 28546001 P 20010420
• US 94226501 A 20010827

Abstract (en)

[origin: WO02087117A1] Optical wireless links (4, 6) automatically re-acquire alignment after detecting the loss of an incoming signal bearing light beam (16, 20). The loss of the signal may be due to a temporary blockage of the light path, so the devices (4, 6) will await a programmable period of time before attempt to re-align themselves. If re-alignment is required, the devices (4, 6) will first position their light beams to the last known aligned position and will from that point sweep through a pattern seeking to re-align with the remote device. The devices (4, 6) transmit their beam position information during the sweep, which information will be echoed back or fed back to the device once its beam impinges upon the remote devices photodetectors. If the devices cannot re-align, then a second, longer sweep pattern may be performed, starting at some predefined default location.

IPC 1-7

H04B 10/00

IPC 8 full level

H04B 10/112 (2013.01); H04B 10/114 (2013.01)

CPC (source: EP)

H04B 10/1123 (2013.01); H04B 10/1149 (2013.01)

Citation (search report)

• [X] US 5592320 A 19970107 - WISSINGER ALAN B [US]
• [A] EP 0856958 A2 19980805 - AT & T CORP [US]
• [A] WO 0004653 A2 20000127 - DOMINION COMMUNICATIONS LLC [US]
• See references of WO 02087117A1

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

WO 02087117 A1 20021031; EP 1386425 A1 20040204; EP 1386425 A4 20071107

DOCDB simple family (application)

US 0212571 W 20020419; EP 02764279 A 20020419