Allocating orthogonal frequency-division multiple access (OFDMA) resources in ethernet passive optical network(PON) over coaxial (EPOC)

• US 9,344,239 B2
• Filed: 04/22/2014
• Issued: 05/17/2016
• Est. Priority Date: 04/22/2013
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Sun, Fanglin, Pan, Dao, Zhang, Li, Chen, Jim
• Primary Examiner(s): Leung, Danny
• Application Number:
  US14/258,419
• Publication Number:
  US 20140314418A1
• Time in Patent Office: 756 Days
• US Class Current: 1/1
• CPC Class Codes: H04B 10/27 Arrangements for networking
• CPC Class Codes: H04B 3/00 Line transmission systems combined with near-field transmission systems H04B5/00
• CPC Class Codes: H04J 14/00 Optical multiplex systems
• CPC Class Codes: H04J 2203/0089 Multiplexing, e.g. coding, scrambling, SONET
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 27/2697 in combination with other modulation techniques
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04Q 11/0067 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 Class Codes: H04Q 11/0071 Provisions for the electrical-optical layer interface
• CPC Class Codes: H04Q 2011/0064 Arbitration, scheduling or medium access control aspects

Abstract

A method implemented in a Fiber Coaxial Unit (FCU) comprising receiving a plurality of Ethernet Passive Optical Network (EPON) report messages from a plurality of Coaxial Network Units (CNUs) across a coaxial network, receiving an EPON gate message comprising Time Quanta (TQ) information indicating an upstream transmission time grant for the FCU across the optical network, translating the TQ based upstream transmission time grants to OFDM resource block grants in a time domain and in a frequency domain across the coaxial network for each CNU based on the configurable constants, and transmitting an EPON over Coaxial (EPoC) gate message to each CNU, wherein each EPoC gate message comprises a CNU profile indicating the Orthogonal Frequency-Division Multiplexing (OFDM) resource block grants for the an associated CNU and a start time.

Claims

1. A Coaxial Network Unit (CNU) comprising:

a transmitter configured to transmit an Ethernet Passive Optical Network (EPON) report message toward an Optical Line Terminal (OLT) via a coaxial network and an optical network, wherein the EPON report message requests an upstream transmission time grant to transmit a specified amount of data;

a receiver configured to receive an EPON gate message comprising Time Quanta (TQ) information indicating an upstream transmission time grant across the optical network; and

a processor coupled to the receiver and the transmitter and configured to;

obtain a resource profile indicating upstream frequency parameters associated with the coaxial network;

translate the TQ information and the resource profile into one or more Orthogonal Frequency-Division Multiplexing (OFDM) resource blocks, wherein each OFDM resource block indicates an upstream OFDM resource allocation in a time domain and in a frequency domain across the coaxial network; and

schedule an upstream transmission by employing the OFDM resource blocks translated from the TQ information and the resource profile,

wherein all subcarriers in any OFDM resource block employ a common Quadrature Amplitude Modulation (QAM) constellation, and wherein subcarriers in a first of the OFDM resource blocks employs different QAM constellations than subcarriers in a second of the OFDM resource blocks.

2. The GNU of claim 1, wherein each OFDM resource block comprises a common bit loading capacity with all other OFDM resource blocks.

3. The CNU of claim 1, wherein a first of the OFDM resource blocks comprises a first bit loading capacity, wherein a second of the OFDM resource blocks comprises a second bit loading capacity, and wherein the bit loading capacity of the first OFDM resource block is different from the bit loading capacity of the second OFDM resource block.

4. The GNU of claim 1, wherein each OFDM resource block comprises a common number of active subcarriers as all other OFDM resource blocks.

5. The GNU of claim 1, wherein the TQ information is expressed in units configured for the optical network, wherein the EPON gate message further comprises a configurable constant that indicates a relationship between the optical network TQ information and time units in the coaxial network, and wherein processor employs the configurable constant to translate the TQ information and the resource profile into the OFDM resource blocks.

6. The GNU of claim 1, wherein the resource profile is based on the amount of data requested in the EPON report message.

7. The CNU of claim 1, wherein the resource profile indicates a plurality of profile pointers, and wherein the CNU is configured to:

transmit at least some of the data in an upstream OFDM symbol using time and frequency resources specified in the OFDM resource blocks; and

insert the profile pointers in the upstream OFDM symbol to separate the OFDM resource blocks.

8. A method implemented in a Coaxial Line terminal (CLT) comprising:

receiving a plurality of an Ethernet Passive Optical Network (EPON) report messages from a plurality of Coaxial Network Units (CNUs) across a coaxial network;

receiving an EPON gate message comprising Time Quanta (TQ) information indicating an upstream transmission time grant for the CLT across an optical network;

translating TQ based upstream transmission time grants to Orthogonal Frequency-Division Multiplexing (OFDM) resource block grants in a time domain and in a frequency domain across the coaxial network for each CNU based on the configurable constants; and

transmitting an EPON over Coaxial (EPoC) gate message to each CNU,

wherein each EPoC gate message comprises a CNU profile indicating the OFDM resource block grants for an associated CNU and a start time,

wherein the OFDM resource blocks are selected to allow a plurality of the CNUs to perform upstream transmission by employing a common OFDM symbol in different frequencies.

9. The method of claim 8, wherein each OFDM resource block grant comprises a common bit loading capacity with all other OFDM resource block grants.

10. The method of claim 8, wherein each OFDM resource block grant comprises a common number of active subcarriers as all other resource block grants.

11. The method of claim 8, wherein all subcarriers in any OFDM resource block employ a common Quadrature Amplitude Modulation (QAM) constellation, and wherein subcarriers in a first of the OFDM resource blocks employs different QAM constellations than subcarriers in a second of the OFDM resource blocks.

12. The method of claim 8, wherein translating the TQ based upstream transmission time grants to OFDM resource block grants comprises employing an FEC (Forward Error Correction) coding scheme for upstream transmissions based on pay load data sizes requested in the EPON report messages.

13. A method comprising:

receiving, by an Optical Line Terminal (OLT), a plurality of Ethernet Passive Optical Network (EPON) report messages from a plurality of Coaxial Network Units (CNUs) via an electro-optical network, wherein the EPON report messages request upstream transmission grants;

allocating at least one Orthogonal Frequency-Division Multiplexing (OFDM) resource block to each CNU for upstream transmission, wherein each resource block comprises allocated upstream OFDM resources in a time domain and in a frequency domain across a coaxial portion of the electro-optical network; and

transmitting EPON gate messages across the electro-optical network to indicate the resource block allocations for the CNUs,

wherein the resource blocks are allocated based on profiles associated with each CNU, and wherein the profiles indicate bit loading capacities associated with each CNU.

14. The method of claim 13, wherein each OFDM resource block comprises a plurality of subcarriers, and wherein all resource blocks comprise a common number of subcarriers.

15. The method of claim 13, wherein each OFDM resource block comprises a bit loading capacity, and wherein all resource blocks comprise a common bit loading capacity.

16. The method of claim 13, wherein at least one of the EPON gate messages instructs an associated CNU to insert a profile pointer in an upstream transmission associated with a first Logical Link Identifier (LLID) to separate a first LLID upstream transmission from upstream transmissions associated with a second LLID.

17. The method of claim 13, wherein each OFDM resource block comprises a plurality of subcarriers, and wherein all active subcarriers in a specified resource block comprise a common modulation order.