METHOD AND SYSTEM FOR A HIGH CAPACITY CABLE NETWORK

• US 20160056969A1
• Filed: 11/02/2015
• Published: 02/25/2016
• Est. Priority Date: 07/23/2012
• Status: Active Grant

• Current Assignee: Entropic Communications, LLC (SoftBank Group Corp.)
• Original Assignee: Maxlinear Incorporated
• Inventors: Ling, Curtis, Ramesh, Sridhar, Gallagher, Timothy
• Granted Patent: US 9,621,367 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 12/2898 Subscriber equipments DSL modems H04M11/062; cable modems H04L12/2801
• CPC Class Codes: H04L 27/2646 using feedback from receiver for adjusting OFDM transmission parameters, e.g. transmission timing or guard interval length
• CPC Class Codes: H04L 41/083 for increasing network speed
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

A cable modem termination system (CMTS) may communicate with a plurality of cable modems using a plurality of orthogonal frequency division multiplexed (OFDM) subcarriers. The CMTS may determine a performance metric of each of the cable modems. For each of the OFDM subcarriers and each of the cable modems, the CMTS may select physical layer parameters to be used for communication with that cable modem on that OFDM subcarrier based on a performance metric of that cable modem. The parameters may be selected for each individual modem and/or each individual subcarrier, or may be selected for groups of modems and/or groups of subcarriers. The parameters may include, for example, one or more of: transmit power, receive sensitivity, timeslot duration, modulation type, modulation order, forward error correction (FEC) type, and FEC code rate.

Claims

1-8. -8. (canceled)

9. A method comprising:

selecting, by a cable modem termination system (CMTS) which communicates with a plurality of cable modems using a plurality of orthogonal frequency division multiplexed (OFDM) subcarriers, physical layer parameters to be used for said communication such that there is excess signal-to-noise ratio, relative to a threshold SNR required for said communication, on a first subset of said OFDM subcarriers, and a SNR deficit, relative to said threshold SNR, on a second set of said OFDM subcarriers.

10. The method of claim 9, comprising transmitting, on said first subset of said OFDM subcarriers, parity bits for packets sent on said second subset of said OFDM subcarriers.

11. The method of claim 9, comprising transmitting, on said first subset of said OFDM subcarriers, replacement bits for packets sent on said second subset of said OFDM subcarriers.

12. The method of claim 9, wherein said physical layer parameters include one or more of:

transmit power, receive sensitivity, timeslot duration, modulation type, modulation order, forward error correction (FEC) type, and FEC code rate.

24. The method of claim 9, wherein said selecting said physical layer parameters includes selecting whether to use hierarchical modulation for said communication with said one of said cable modems.

13-14. -14. (canceled)

15. A system comprising:

a cable modem termination system (CMTS) operable to;

communicate with a plurality of cable modems using a plurality of orthogonal frequency division multiplexed (OFDM) subcarriers;

determine a performance metric of each of said cable modems; and

for each one of said plurality of OFDM subcarriers and each one of said cable modems, select physical layer parameters to be used for said communication with said one of said cable modems on said one of said OFDM subcarriers based on a performance metric of said one of said cable modems, wherein;

said performance metric is a signal-to-noise ratio (SNR) profile across said OFDM subcarriers;

said plurality of cable modems belong to a single service group; and

said physical layer parameters are selected such that a threshold SNR required for receiving a packet broadcast to said service group is higher than a subset of said SNR profiles corresponding to a subset of said cable modems.

17. The system of claim 15, wherein said selection of said physical layer parameters includes selection of whether to use hierarchical modulation for said communication with said one of said cable modems.

26. The system of claim 15, wherein said physical layer parameters include one or more of:

transmit power, receive sensitivity, timeslot duration, modulation type, modulation order, forward error correction (FEC) type, and FEC code rate.

16. (canceled)

18-19. -19. (canceled)

20. A system comprising:

a cable modem termination system (CMTS) operable to;

communicate with a plurality of cable modems using a plurality of orthogonal frequency division multiplexed (OFDM) subcarriers; and

select physical layer parameters to use for said communication such that there is excess signal-to-noise ratio (SNR), relative to a threshold SNR required for said communication, on a first subset of said OFDM subcarriers and a SNR deficit, relative to said threshold SNR, on a second set of said OFDM subcarriers.

21. The system of claim 20, wherein said CMTS is operable to transmit, on said first subset of said OFDM subcarriers, parity bits for packets sent on said second subset of said OFDM subcarriers.

22. The system of claim 20, wherein said CMTS is operable to transmit, on said first subset of said OFDM subcarriers, replacement bits for packets sent on said second subset of said OFDM subcarriers.

23. The system of claim 20, wherein said physical layer parameters include one or more of:

transmit power, receive sensitivity, timeslot duration, modulation type, modulation order, forward error correction (FEC) type, and FEC code rate.

25. The system of claim 20, wherein said selection of said physical layer parameters includes selection of whether to use hierarchical modulation for said communication with said one of said cable modems.

27. The system of claim 20, wherein said physical layer parameters include one or more of:

transmit power, receive sensitivity, timeslot duration, modulation type, modulation order, forward error correction (FEC) type, and FEC code rate.