OPTICAL ACCESS SYSTEM AND RANGING METHOD THEREFOR

• Main Author: EGUCHI KOHEI
• Format: Patent
• Language: English
• Published: 13.11.2008
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; MULTIPLEX COMMUNICATION; SELECTING; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

PROBLEM TO BE SOLVED: To provide a system for performing ONU (optical network unit) ranging without interrupting other ONU providing services at low cost. SOLUTION: A ranging signal R1 is generated by a signal generator 211 and reaches a signal checker 212 via an active system transmission path 131, a loop circuit 251, a standby system transmission path 132 and a loop circuit 253. The signal checker 212 uses a timer 213 for measuring the delay time between the generation of the signal R1 and the arrival of the signal R1. A ranging signal R2 is generated by a signal generator 221 and reaches a signal checker 222 via the standby system transmission path 132, a loop circuit 252 and the standby system transmission path 132. The signal checker 222 uses a timer 223 to measures the delay time between the generation of the signal R2 and the arrival of the signal. The delay time of the active system transmission path 131 is calculated from the delay times of the signals R1 and R2. Since the active system transmission path 131 is not used for incoming communication of the ranging signals R1 and R2, there is no need to have the other ONU providing services interrupted. COPYRIGHT: (C)2009,JPO&INPIT