Patent Application
20080166133
1. Field of the Invention
This invention relates to optical networking technologies, and more particularly, to an optical network remote power supply system which is designed for use with an optical network having a remote switching unit, for supplying power to the remote switching unit from a local site.
2. Description of Related Art
Optical networking is a communication technology for data transmission between computers, telephones and other electronic devices using laser beams transmitted through optical fibers. Optical networks can be used to transmit signals either in analog or digital forms. Since laser beams are much higher in frequency than electrical and radio signals, optical networking is far more reliable and has far greater transmission capacity than traditional cable and radio communications.
Passive optical network (PON) systems are a widely employed technology for data communication between the Internet and local area networks that are used for connection to private users and small business entities. In practice, a PON system typically utilizes just one single strand of optical fiber for two-way transmission of optical signals to and from the client sites.
One drawback to the traditional single-fiber two-way PON systems, however, is that when the single fiber is damaged or fractured, the data communication to the client sites is entirely disconnected. One solution to this problem is to provide two channels (i.e., two strands of fibers) in the optical transmission path: a primary channel and a secondary channel, where the primary channel is initially set to active mode while the secondary channel is set to standby (backup) mode, such that in the event of a failure to the primary channel (such as when fractured), the optical transmission path can be promptly switched to the secondary channel. To achieve this purpose, a present solution is to provide a local switching unit and a remote switching unit on both sides of the optical network, such that in the event of a failure to the primary channel, both of these two switching units can be activated to perform the required switching actions.
In practice, however, since a PON system has a passive optical data processing unit on the remote site (i.e., the remote optical data processing unit has no internal power supply), there exists a need for an optical network remote power supply system that can supply power to the remote switching unit.
It is therefore an objective of this invention to provide a optical network remote power supply system which is capable of supplying electrical power to a remote switching unit in an optical network system.
The optical network remote power supply system according to the invention is designed for use with an optical network system, particularly a PON (Passive Optical Network) system, for supplying power to a remote switching unit from the local site.
In assembly, the optical network remote power supply system according to the invention is based on a distributed architecture comprising: (A) a local power source unit; and (B) a remote power storage unit; wherein the local power supply unit is integrated to the local switching unit and includes: (A1) a light-emitting module, which is capable of emitting a light beam; and (A2) a light-beam multiplexing module, which is coupled to a light output port of the local optical data processing unit for injecting the light beam emitted from the light-emitting module in a multiplexed manner into the optical transmission line for transmission through the optical transmission line to the remote switching unit; and wherein the remote power storage unit is integrated to the remote switching unit and includes: (B1) a light division module, which is capable of dividing the light beam that is transmitted by the local power source unit through the optical transmission line from the remote optical data processing unit; (B2) a light-to-electricity transducer module, which is capable of converting the energy of the light beam received by the light division module into electrical energy; and (B3) an electrical energy storage module, which is used to store the electrical energy produced by the light-to-electricity transducer module and utilize the stored electrical energy as a power source for the remote switching unit.
The optical network remote power supply system according to the invention is characterized by the provision of a light source on the local site which can transmit a light beam via the optical transmission line to the remote site, where the light beam is converted into electricity for storage in an electrical energy storage module, such as a rechargeable battery unit or a capacitor. This feature allows the remote switching unit to be powered by the electricity stored in the electrical energy storage module in the event of a failure to the primary channel when the remote switching unit is responsible for switching to the secondary channel.
The invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:
The optical network remote power supply system according to the invention is disclosed in full details by way of preferred embodiments in the following with reference to the accompanying drawings.
In actual operation, the local optical data processing unit 10 and the remote optical data processing unit 20 can communicate with each other via the optical transmission line 30 by means of laser beams. The local optical data processing unit 10 includes a light transmitting port (Tx) 11 and a light reception port (Rx) 12; and similarly, the remote optical data processing unit 20 also includes a light transmitting port (Tx) 21 and a light reception port (Rx) 22. The local optical data processing unit 10 is capable of emitting a signal beam OP(λ1) having a wavelength of λ1; and the remote optical data processing unit 20 is capable of emitting a signal beam OP(λ3) having a wavelength of λ3. Initially, the local switching unit 40 and the remote switching unit 50 are set to connect the primary channel 31 of the optical transmission line 30 between the local optical data processing unit 10 and the remote optical data processing unit 20, such that the local optical data processing unit 10 and the remote optical data processing unit 20 can transmit the signal beams OP(λ1) and OP(λ3) via the primary channel 31; and in the event of a failure to the primary channel 31, both the local switching unit 40 and the remote switching unit 50 will be activated to switch the connection to the secondary channel 32, such that the local optical data processing unit 10 and the local optical data processing unit 10 can nevertheless utilize the secondary channel 32 for transmitting the signal beams OP(λ1) and OP(λ3).
In the above-mentioned switching action, the electrical power needed by the local switching unit 40 can be directly supplied by the local optical data processing unit 10; but in a PON system, since the remote switching unit 50 has no power supply, the needed electrical power is supplied by the optical network remote power supply system of the invention 60.
As shown in
The light-emitting module 110 is capable of emitting a light beam, such as a laser diode capable of emitting a laser beam OP(λ2), where λ2≠λ1≠λ3, and which is driven by an electrical voltage VL supplied by the local optical data processing unit 10.
The light-beam multiplexing module 120 is for example a WDM (Wavelength Division Multiplexer) device, which is coupled to the light transmitting port (Tx) 11 of the local optical data processing unit 10 for injecting the light beam OP(λ2) emitted from the light-emitting module 110 in a multiplexed manner into the optical transmission line 30 for transmission together with the signal beam OP(λ1) through the optical transmission line 30 to the remote switching unit 50.
The light division module 210 can also be implemented with a WDM device, and which can be coupled to the optical network in several different manners. For example, as illustrated in
The light-to-electricity transducer module 220 is capable of converting the energy of the light beam OP(λ2) received by the light division module 210 into electrical energy. In practical implementation, for example, the light-to-electricity transducer module 220 can be a light-sensitive diode or a solar cell, which can output an electrical current Iop in response to the OP(λ2).
The electrical energy storage module 230 is capable of being charged by the electrical current Iop produced by the light-to-electricity transducer module 220 and thereby storing the electrical energy from Iop as a power source for the remote switching unit 50 when the remote switching unit 50 needs to perform a switching action. In practical implementation, for example, the electrical energy storage module 230 can be either a rechargeable battery unit or a capacitor. After being charged to full capacity, the electrical energy storage module 230 is capable of providing an electrical voltage VSW to drive both the optical switches 51, 52 in the remote switching unit 50 to perform a switching action when activated.
In addition to the embodiments shown in
The following is a detailed description of a practical application example of the optical network remote power supply system of the invention 60 during actual operation, which is described with reference to
As shown in
At the remote switching unit 50, the laser beam OP(λ2) is intercepted by the light division module (WDM) 210 and then transferred to the light-to-electricity transducer module 220, where the laser beam OP(λ2) is converted into electricity in the form of an electrical current Iop. The electrical energy of Iop is then stored into the electrical energy storage module 230 (which can be either a rechargeable battery or a capacitor).
Thereafter, in the event of a failure to the primary channel 31 of the optical transmission line 30 when it is necessary to switch to the secondary channel 32, the local switching unit 40 and the remote switching unit 50 will be activated to cooperatively perform the required switching action. Under this condition, the local switching unit 40 can be powered by the local optical data processing unit 10 to perform the switching action, whereas the remote switching unit 50 can be powered by the output voltage VSW of the electrical energy storage module 230.
In the case of the embodiment of
In conclusion, the invention provides an optical network remote power supply system which is designed for use with an optical network for supplying power to a remote switching unit, and which is characterized by the provision of a light source on the local site which can transmit a light beam via the optical transmission line to the remote site, where the light beam is converted into electricity for storage in an electrical energy storage module, such as a rechargeable battery unit or a capacitor. This feature allows the remote switching unit to be powered by the electricity stored in the electrical energy storage module in the event of a failure to the primary channel when the remote switching unit is responsible for switching to the secondary channel. The invention is therefore more advantageous to use than the prior art.
The invention has been described using exemplary preferred embodiments. However, it is to be understood that the scope of the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements. The scope of the claims, therefore, should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
