Synchronizing nodes in an optical communications system utilizing frequency division multiplexing
First Claim
Patent Images
1. In an optical fiber communications system including a transmitter node coupled to a receiver node by an optical fiber, a method for synchronizing the receiver node with the transmitter node, the method comprising:
- at the transmitter node;
generating a reference signal;
synchronizing the transmitter node with the reference signal;
modulating the reference signal onto an optical signal; and
transmitting the optical signal across the optical fiber to the receiver node; and
at the receiver node;
receiving the optical signal;
recovering the reference signal from the optical signal; and
synchronizing the receiver node with the recovered reference signal.
3 Assignments
0 Petitions
Accused Products
Abstract
Two nodes in an optical fiber communications system are synchronized by transmitting a reference signal between the two. The reference signal (or a harmonic of the reference signal) is generated at one node and then transmitted across an optical fiber to the other node. Both nodes are synchronized to the reference signal, thus synchronizing each node to the other. In one embodiment, the reference signal is combined with data to be transmitted between the nodes using frequency division multiplexing.
-
Citations
6 Claims
-
1. In an optical fiber communications system including a transmitter node coupled to a receiver node by an optical fiber, a method for synchronizing the receiver node with the transmitter node, the method comprising:
-
at the transmitter node;
generating a reference signal;
synchronizing the transmitter node with the reference signal;
modulating the reference signal onto an optical signal; and
transmitting the optical signal across the optical fiber to the receiver node; and
at the receiver node;
receiving the optical signal;
recovering the reference signal from the optical signal; and
synchronizing the receiver node with the recovered reference signal. - View Dependent Claims (2, 3, 4, 5)
-
-
6. An optical fiber communications system for transmitting at least two low-speed channels across the communications system, the communications system comprising:
-
a transmitter node including;
a local oscillator for generating a reference signal; and
an FDM multiplexer coupled to the local oscillator for combining the low-speed channels with the reference signal into an electrical high-speed channel; and
a receiver node coupled to the transmitter node by an optical fiber, the receiver node including;
an FDM demultiplexer for recovering the reference signal from the electrical high-speed channel;
a local oscillator; and
electronics coupled to the local oscillator and the FDM demultiplexer for synchronizing the local oscillator with the recovered reference signal.
-
Specification