US 8,913,887 B2 · Passive optical fiber plant analysis

Abstract

In a first aspect, the method and apparatus of the present disclosure can be used to periodically and/or intermittently place one or more ONUs attached to a PON in a power savings mode so that an OTDR test can be performed. While in the power savings mode, the ONUs temporarily suspend their transmitter function and power down their upstream lasers. In a second aspect, the method and apparatus of the present disclosure can be used to coordinate the performance of OTDR during one or more periodic or intermittent discovery slots used to detect and register ONUs recently connected to the PON. Because new ONUs are infrequently connected to the PON and ONUs already registered are not permitted to transmit during the discovery windows, OTDR can be performed during these windows without impacting, to a great degree, the normal operation of the PON.

Claims21

Dependent claims

An optical line terminal (OLT) configured to perform optical time-domain reflectometry (OTDR) to locate an interruption in a passive optical network (PON), the OLT comprising:

a PON controller configured to transmit a power-saving initiation command to an optical network unit (ONU) over the PON to place the ONU in a power savings mode;
and
an OTDR module configured to inject a pulse into the PON and analyze a signal reflected back over the PON from the injected pulse to locate the interruption in the PON,
wherein the OTDR module injects the pulse into the PON after receiving an indication that the ONU has accepted the power-saving initiation command and is in the power savings mode.

1 more element

Dependencies are inferred from the claim text.

Passive optical fiber plant analysis

Life of this patent

Passive optical fiber plant analysis

Life of this patent

Abstract

Claims21