Method, apparatus, and system for adjusting emission parameter of laser in WDM-PON

An apparatus for adjusting an emission parameter of a laser, wherein the apparatus is applied to a wavelength division multiplexing passive optical network system, and wherein the apparatus comprises:

• a monitoring device configured to monitor a power value of output light of the laser and a power value of reflected light, wherein the reflected light is light reflected back by a Faraday rotation mirror when the output light passes through the Faraday rotation mirror;
• a processing device configured to:
• obtain an insertion loss value according to the power value of the output light, the power value of the reflected light, and a parameter of the Faraday rotation mirror;
• and
• obtain a bias current value according to the insertion loss value, wherein the insertion loss value is a power loss, of the output light of the laser, on a one-way link between the laser and the Faraday rotation mirror;
• and
• a driving device configured to adjust power of the output light of the laser using the obtained bias current value.

An optical network unit, comprising:

• a laser;
• and
• an apparatus for adjusting an emission parameter of the laser, wherein the apparatus is applied to a wavelength division multiplexing passive optical network system, and wherein the apparatus comprises:
• a monitoring device disposed on a transmission channel of output light of the laser and configured to monitor a power value of output light of the laser and a power value of reflected light, wherein the reflected light is light reflected back by a Faraday rotation mirror when the output light passes through the Faraday rotation mirror;
• a processing device connected to the monitoring device and configured to:
• obtain an insertion loss value according to the power value of the output light, the power value of the reflected light, and a parameter of the Faraday rotation mirror;
• and
• obtain a bias current value according to the insertion loss value, wherein the insertion loss value is a power loss, of the output light of the laser, on a one-way link between the laser and the Faraday rotation mirror;
• and
• a driving device separately connected to the processing device and the laser and configured to adjust power of the output light of the laser using the obtained bias current value.

An optical line terminal, comprising:

• a laser;
• and
• an apparatus for adjusting an emission parameter of the laser,
• wherein the apparatus is applied to a wavelength division multiplexing passive optical network system, and wherein the apparatus comprises:
• a monitoring device disposed on a transmission channel of output light of the laser and configured to monitor a power value of the output light of the laser and a power value of reflected light, wherein the reflected light is light reflected back by a Faraday rotation mirror when the output light passes through the Faraday rotation mirror;
• a processing device connected to the monitoring device and configured to:
• obtain an insertion loss value according to the power value of the output light, the power value of the reflected light, and a parameter of the Faraday rotation mirror;
• and
• obtain a bias current value according to the insertion loss value, wherein the insertion loss value is a power loss, of the output light of the laser, on a one-way link between the laser and the Faraday rotation mirror;
• and
• a driving device separately connected to the processing device and the laser and configured to adjust power of the output light of the laser using the obtained bias current value.

A wavelength division multiplexing passive optical network system, wherein the system comprises:

• an optical network unit;
• an optical line terminal;
• two optical multiplexers;
• and
• two Faraday rotation mirrors,
• wherein the optical network unit is connected to a distribution port of a first optical multiplexer, wherein a first Faraday rotation mirror is disposed at a common port of the first optical multiplexer, and wherein the optical network unit comprises:
• a laser;
• and
• an apparatus for adjusting an emission parameter of the laser, wherein the apparatus is applied to the wavelength division multiplexing passive optical network system, and wherein the apparatus comprises:
• a monitoring device disposed on a transmission channel of output light of the laser and configured to monitor a power value of the output light of the laser and a power value of reflected light, wherein the reflected light is light reflected back by the first Faraday rotation mirror when the output light passes through the first Faraday rotation mirror;
• a processing device connected to the monitoring device and configured to:
• obtain an insertion loss value according to the power value of the output light, the power value of the reflected light, and a parameter of the first Faraday rotation mirror;
• and
• obtain a bias current value according to the insertion loss value, wherein the insertion loss value is a power loss, of the output light of the laser, on a one-way link between the laser and the first Faraday rotation mirror;
• and
• a driving device separately connected to the processing device and the laser and configured to adjust power of the output light of the laser using the obtained bias current value,
• wherein the optical line terminal is connected to a distribution port of a second optical multiplexer, wherein a second Faraday rotation mirror is disposed at a common port of the second optical multiplexer, wherein the optical line terminal comprises a second apparatus for adjusting an emission parameter of a second laser, wherein the second apparatus is applied to the wavelength division multiplexing passive optical network system, and wherein the second apparatus comprises:
• a second monitoring device disposed on a transmission channel of output light of the second laser and configured to monitor a power value of output light of the second laser and a power value of a second reflected light, wherein the second reflected light is light reflected back by the second Faraday rotation mirror when the output light of the second laser passes through the second Faraday rotation mirror;
• a second processing device connected to the second monitoring device and configured to:
• obtain a second insertion loss value according to the power value of the output light of the second laser, the power value of the second reflected light, and a parameter of the second Faraday rotation mirror;
• and
• obtain a second bias current value according to the second insertion loss value, wherein the second insertion loss value is a power loss, of the output light of the second laser, on a one-way link between the second laser and the second Faraday rotation mirror;
• and
• a second driving device separately connected to the second processing device and the second laser and configured to adjust power of the output light of the second laser using the obtained second bias current value,
• wherein an output end of the first Faraday rotation mirror is connected to an output end of the second Faraday rotation mirror,
• wherein the first optical multiplexer is configured to:
• multiplex output light, received by the distribution port, of the optical network unit;
• output the output light to the common port of the first optical multiplexer;
• and
• demultiplex, to the distribution port, a part of a multiplexed optical signal reflected back by the first Faraday rotation mirror, wherein the first Faraday rotation mirror is configured to:
• reflect back, to the common port of the first optical multiplexer, the part of the multiplexed optical signal that is output by the common port of the first optical multiplexer;
• and
• transmit the other part of the multiplexed optical signal that is output by the common port of the first optical multiplexer to a transmission fiber, wherein the second optical multiplexer is configured to:
• multiplex output light of the second laser, received by the distribution port, of the optical line terminal;
• output the output light of the second laser to the common port the second optical multiplexer;
• and
• demultiplex, to the distribution port, a part of a multiplexed optical signal reflected back by the second Faraday rotation mirror, and wherein the second Faraday rotation mirror is configured to:
• reflect back, to the common port of the second optical multiplexer, the part of the multiplexed optical signal that is output by the common port of the second optical multiplexer;
• and
• transmit the other part of the multiplexed optical signal that is output by the common port of the second optical multiplexer to the transmission fiber.