Power control in an optical network unit
There are disclosed techniques for power control in an Optical Network Unit (ONU) of a Passive Optical Network (PON). In one embodiment, the supply of power to an optical transmitter is controlled in accordance with information defining a plurality of transmission windows during which data can be transmitted from the ONU, in order to achieve the following: (1) to provide power to the optical transmitter beginning at a predetermined time in advance of a transmission window to ensure a laser in the optical transmitter is ready to begin transmitting the data at the start of the transmission window; and (2) to refrain from providing full power to the optical transmitter between transmission windows when the duration of time between the transmission windows is greater than a predetermined length.
1. A method of power control in an Optical Network Unit (ONU), the ONU having an optical transmitter coupled to a power controller, the method comprising:
receiving at least one message at the ONU, the at least one message comprising information defining a plurality of transmission windows during which data can be transmitted from the ONU;
controlling a supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to provide power to an optical transmitter in the ONU beginning at a predetermined time in advance of a transmission window of the plurality of transmission windows to ensure a laser in the optical transmitter is ready to begin transmitting the data at the start of the transmission window;
controlling the supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window of the plurality of transmission windows, when the duration of time between the end of the transmission window and the start of the next transmission window is greater than a predetermined length.
2. The method of claim 1 , wherein said controlling the supply of power to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window comprises controlling the supply of power to refrain from providing any power to the optical transmitter during a period of time between the end of the transmission window and the start of the next transmission window.
3. The method of claim 1 further comprising:
if data ready to be transmitted from the ONU during one transmission window of the plurality of transmission windows satisfies a criterion:
controlling the supply of power to refrain from providing full power to the optical transmitter during the one transmission window.
4. The method of claim 3 wherein the criterion is that the amount of the data ready to be transmitted is less than a predetermined value.
5. The method of claim 1 wherein the predetermined length is at least as great as a summation of a period of time required for the optical transmitter to wake-up and a period of time required for the optical transmitter to shut-down.
6. The method of claim 5 wherein the period of time required for the optical transmitter to wake-up is representative of the time between initially providing power to the optical transmitter and the laser being ready to begin transmitting the data, and wherein the period of time required for the optical transmitter to shut-down is representative of a minimum amount of time during which the power must be terminated before the power can again be provided to the optical transmitter.
7. The method of claim 1 further comprising:
controlling the supply of power in accordance with the information to provide full power to a data processing block in the ONU during the transmission window;
controlling the supply of power in accordance with the information to refrain from providing full power to the data processing block during a period of time between the end of the transmission window and the start of the next transmission window.
8. The method of claim 1 wherein the optical transmitter is a transmission portion of an optical transceiver in the ONU.
9. An Optical Network Unit (ONU) comprising:
an optical transmitter having a laser;
an optical receiver for receiving at least one message at the ONU, the at least one message comprising information defining a plurality of transmission windows during which data can be transmitted from the ONU;
a power controller for:
controlling a supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to provide power to the optical transmitter beginning at a predetermined time in advance of a transmission window of the plurality of transmission windows to ensure the laser is ready to begin transmitting the data at the start of the transmission window;
controlling the supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window of the plurality of transmission windows, when the duration of time between the end of the transmission window and the start of the next transmission window is greater than a predetermined length.
10. The ONU of claim 9 wherein said controlling the supply of power to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window comprises controlling the supply of power to refrain from providing any power to the optical transmitter during a period of time between the end of the transmission window and the start of the next transmission window.
11. The ONU of claim 9 , wherein the power controller is further configured to perform the operation of:
if data ready to be transmitted from the ONU during one transmission window of the plurality of transmission windows satisfies a criterion:
controlling the supply of power to refrain from providing full power to the optical transmitter during the one transmission window.
12. The ONU of claim 11 wherein the criterion is that the amount of the data ready to be transmitted is less than a predetermined value.
13. The ONU of claim 9 wherein the predetermined length is at least as great as a summation of a period of time required for the optical transmitter to wake-up and a period of time required for the optical transmitter to shut-down.
14. The ONU of claim 13 wherein the period of time required for the optical transmitter to wake-up is representative of the time between initially providing power to the optical transmitter and the laser being ready to begin transmitting the data, and wherein the period of time required for the optical transmitter to shut-down is representative of a minimum amount of time during which the power must be terminated before the power can again be provided to the optical transmitter.
15. The ONU of claim 9 , wherein the power controller is further for:
controlling the supply of power in accordance with the information to provide full power to a data processing block in the ONU during the transmission window;
controlling the supply of power in accordance with the information to refrain from providing full power to the data processing block during a period of time between the end of the transmission window and the start of the next transmission window.
16. The ONU of claim 9 wherein the optical transmitter is a transmission portion of an optical transceiver in the ONU, and wherein the optical receiver is a receiving portion of the optical transceiver.
17. A computer readable medium having stored thereon computer readable instructions for performing a method of power control in an Optical Network Unit (ONU), the computer readable instructions including instructions for performing operations comprising:
receiving at least one message at the ONU, the at least one message comprising information defining a plurality of transmission windows during which data can be transmitted from the ONU;
controlling a supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to provide power to an optical transmitter in the ONU beginning at a predetermined time in advance of a transmission window of the plurality of transmission windows to ensure a laser in the optical transmitter is ready to begin transmitting the data at the start of the transmission window;
controlling the supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window of the plurality of transmission windows, when the duration of time between the end of the transmission window and the start of the next transmission window is greater than a predetermined length.
18. The computer readable medium of claim 17 , wherein said controlling the supply of power to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window comprises controlling the supply of power to refrain from providing any power to the optical transmitter during a period of time between the end of the transmission window and the start of the next transmission window.
19. The computer readable medium of claim 17 , wherein the computer readable instructions further include instructions for performing the operation of:
if data ready to be transmitted from the ONU during one transmission window of the plurality of transmission windows satisfies a criterion:
controlling the supply of power refrain from providing full power to the optical transmitter during the one transmission window.
20. The computer readable medium of claim 19 wherein the criterion is that the amount of the data ready to be transmitted is less than a predetermined value.
21. The computer readable medium of claim 17 wherein the predetermined length is at least as great as a summation of a period of time required for the optical transmitter to wake-up and a period of time required for the optical transmitter to shut-down.
22. The computer readable medium of claim 21 wherein the period of time required for the optical transmitter to wake-up is representative of the time between initially providing power to the optical transmitter and the laser being ready to begin transmitting the data, and wherein the period of time required for the optical transmitter to shut-down is representative of a minimum amount of time during which the power must be terminated before the power can again be provided to the optical transmitter.
23. The computer readable medium of claim 17 , wherein the computer readable instructions further include instructions for performing operations comprising:
controlling the supply of power in accordance with the information to provide full power to a data processing block in the ONU during the transmission window;
controlling the supply of power in accordance with the information to refrain from providing full power to the data processing block during a period of time between the end of the transmission window and the start of the next transmission window.
24. The computer readable medium of claim 17 wherein the optical transmitter is a transmission portion of an optical transceiver in the ONU.
25. A Passive Optical Network (PON) comprising an Optical Line Terminator (OLT) in communication with a plurality of Optical Network Units (ONUs), wherein at least one ONU of the plurality of ONUs comprises:
an optical transmitter having a laser;
an optical receiver for receiving at least one message at the ONU, the at least one message comprising information defining a plurality of transmission windows during which data can be transmitted from the ONU;
a power controller for:
controlling a supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to provide power to the optical transmitter beginning at a predetermined time in advance of a transmission window of the plurality of transmission windows to ensure the laser is ready to begin transmitting the data at the start of the transmission window;
controlling the supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window of the plurality of transmission windows, when the duration of time between the end of the transmission window and the start of the next transmission window is greater than a predetermined length.
26. A multipoint control protocol (MPCP) engine for use in an Optical Network Unit (ONU), the MPCP engine for:
receiving at least one message comprising information defining a plurality of transmission windows during which data can be transmitted from the ONU;
controlling a supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to provide power to an optical transmitter in the ONU beginning at a predetermined time in advance of a transmission window of the plurality of transmission windows to ensure a laser in the optical transmitter is ready to begin transmitting the data at the start of the transmission window;
controlling the supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window of the plurality of transmission windows, when the duration of time between the end of the transmission window and the start of the next transmission window is greater than a predetermined length.
27. An Optical Network Unit (ONU) comprising:
an optical transmitter having a laser;
an optical receiver for receiving at least one message at the ONU, the at least one message comprising information defining a plurality of transmission windows during which data can be transmitted from the ONU;
a supply of power;
means for controlling the supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to provide power to the optical transmitter beginning at a predetermined time in advance of a transmission window of the plurality of transmission windows to ensure the laser is ready to begin transmitting the data at the start of the transmission window; and
means for controlling the supply of power, in accordance with the information from the at least one message received at the ONU that defines the plurality of transmission windows, to refrain from providing full power to the optical transmitter during a period of time between the end of the transmission window and the start of a next transmission window of the plurality of transmission windows, when the duration of time between the end of the transmission window and the start of the next transmission window is greater than a predetermined length.