Hybrid multiplexing over passive optical networks

Patent metadata

Field	Value
Publication number	US-9762349-B1
Application number	US-201514860122-A
Country	US
Kind code	B1
Filing date	Sep 21, 2015
Priority date	Sep 21, 2015
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

Systems and methods for providing transmission and reception of hybrid time and wavelength division multiplexed signals on passive optical networks are provided. Networks that use shared transmission media avoid interference between transmitters by restricting the times or wavelengths that given transmitters may use to transmit their messages. The hybrid broadcast WDM TDM PON architecture enables transmitters to use multiple fixed wavelengths for parallel optical transmission within given timeslots to avoid interference with other transmitters and make use of inexpensive fixed optical components to gain a speed advantage over existing architectures while making use of their deployed infrastructure. A single scheduling manager controls the timeslots of upstream and downstream transmissions, which make use of existing standards.

First claim

I claim:

1. A device using a hybrid of wavelength division multiplexing and time division multiplexing, comprising:
an arrayed wave guide (AWG) to interface with a passive optical network (PON);
an array of receivers in communication with the AWG to receive a message encoded on multiple carrier waves, wherein each receiver of the array of receivers is operable to receive from the AWG one of the incoming carrier waves of a distinct wavelength onto which a portion of the message has been encoded;
an array of transmitters in communication with the AWG wherein each transmitter of the array of transmitters is operable to generate an outgoing carrier wave having a distinct wavelength to be multiplexed for transmission over the PON;
a non-tunable transceiver in communication with a destined party;
a controller in communication with the array of receivers and the array of transmitters, the controller including a processor and a memory storage device including instructions, which when executed by the processor are operable to:
read from the array of receivers, wherein each of the receivers reads the portion of the message encoded on the incoming carrier wave of the distinct wavelength of the receiver;
reassemble the message from the portions encoded on the incoming carrier waves into a reassembled message;
transmit, via the non-tunable transceiver, the reassembled message to the destined party over a second network;
receive outgoing messages from the destined party via the second network;
divide the outgoing messages into outgoing portions;
determine when a timeslot to transmit the outgoing message occurs; and
when it is determined the timeslot to transmit the outgoing message has occurred, transmit the outgoing message via the array of transmitters by encoding each of the outgoing portions onto the outgoing carrier waves.

2. The device of claim 1 , wherein the device is an Optical Line Terminal (OLT) associated with a service provider and the destined party is the service provider.

3. The device of claim 2 , wherein the device schedules timeslots for transmission to Optical Network Terminals in communication with the device.

4. The device of claim 1 , wherein the device is an Optical Network Terminal (ONT) associated with a subscriber.

5. The device of claim 4 , wherein the device, in response to receiving the incoming carrier waves, determines whether the subscriber is the destined party;
when it is determined that the subscriber is the destined party, the ONT transmits the reassembled message to the destined party over the second network; and
when it is determined that the subscriber is not the destined party, the ONT discards the reassembled message.

6. The device of claim 1 , wherein a number of transmitters in the array of transmitters is equal to a number of receivers in the array of receivers.

7. The device of claim 1 , wherein a number of transmitters in the array of transmitters and a number of receivers in the array of receivers are selected to comply with a Course Wavelength Division Standard, wherein the receivers are selected to receive the incoming carrier waves spaced by at least 20 nm and the transmitters are selected to transmit outgoing carrier waves spaced by at least 20 nm.

8. The device of claim 1 , wherein a number of transmitters in the array of transmitters and a number of receivers in the array of receivers are selected to comply with a Dense Wavelength Division Standard, wherein the receivers are selected to receive the incoming carrier waves spaced by at least 50 GHz and the transmitters are selected to transmit outgoing carrier waves spaced at least 50 GHz.

9. The device of claim 1 , wherein the PON uses a Gigabit PON (GPON) physical layer specification, and wherein the outgoing messages are encapsulated according to GPON Encapsulation Mode (GEM).

10. The device of claim 1 , wherein the PON uses an Ethernet PON standard (EPON) physical layer specification, and wherein the outgoing messages are encapsulated as Ethernet packets.

11. A method for using a hybrid of wavelength division multiplexing and time division multiplexing, comprising:
receiving a message to transmit over a passive optical network (PON);
dividing the message into a plurality of portions;
determining whether it is time to transmit the plurality of portions;
when it is determined that it is time to transmit the plurality of portions, encoding each portion of the plurality of portions onto a carrier wave; and
transmitting the carrier waves with the plurality of portions over the PON to a non-tunable transceiver.

12. The method of claim 11 , further comprising:
receiving the carrier waves at an Optical Network Terminal (ONT), wherein each of the carrier waves is received via a fixed wavelength receiver paired to one fixed wavelength transmitter used to generate the carrier wave;
determining whether the message is destined for a subscriber associated with the ONT;
when it is determined that the message is destined for the subscriber, reassembling the message from the portions encoded on the carrier waves, and transmitting the message to the subscriber; and
when it is determined that the message is not destined for the subscriber, discarding the message.

13. The method of claim 12 , wherein determining whether the message is destined for a subscriber associated with the ONT comprises determining whether the message was received during a timeslot designated for the subscriber to receive messages.

14. The method of claim 13 , wherein the timeslot designated for the subscriber to receive messages is in sync with a timeslot for the ONT to transmit messages.

15. The method of claim 13 , wherein the timeslot is designated by an Optical Line Terminal in communication with the ONT.

16. The method of claim 11 , wherein determining whether the message is destined for a subscriber associated with the ONT comprises determining whether an overhead of the message contains address information identifying the ONT.

17. The method of claim 11 , further comprising:
receiving the carrier waves at an Optical Line Terminal (OLT), wherein each of the carrier waves is received via a fixed wavelength receiver paired to one fixed wavelength transmitter used to generate the carrier wave;
reassembling the message from the portions encoded on the carrier waves;
segmenting the message from a subsequent message encoded on the carrier waves; and
processing the message to determine a final destination of the message.

18. The method of claim 17 , wherein when a service provider's network is determined to be a final destination of the message, transmitting the message to the service provider' network.

19. The method of claim 17 , wherein when the OLT is determined to be the final destination of the message, further processing the message to respond with content available to the OLT.

20. A system using a hybrid of wavelength division multiplexing and time division multiplexing, comprising:
an optical line terminal (OLT) including an array of OLT non-tunable transceivers in communication with an OLT arrayed wave guide (AWG) and an OLT controller;
a plurality of optical network terminals (ONTs), wherein each ONT includes an array of ONT non-tunable transceivers in communication with an ONT AWG and an ONT controller;
wherein each OLT non-tunable transceiver of the array of OLT non-tunable transceivers is operable to generate a downstream carrier wave having a fixed wavelength to create a plurality of downstream carrier waves;
wherein th

Assignees

• Cox Communications Inc
• Cox Communications Inc

Inventors

• Dai Yuxin

Classifications

• H04Q11/0003

  Details · CPC title

• H04Q11/0067

  Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring · CPC title

• H04Q2011/0045

  Synchronisation · CPC title

• H04Q2011/0033

  using time division switching · CPC title

• H04J14/08

  Time-division multiplex systems · CPC title