POWERLINE COMMUNICATION FRAMES HAVING CRC WITHIN HEADER

• US 20120324322A1
• Filed: 06/20/2012
• Published: 12/20/2012
• Est. Priority Date: 06/20/2011
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: VEDANTHAM, RAMANUJA, XU, GANG, VIJAYASANKAR, KUMARAN, DABAK, ANAND G., PANDE, TARKESH, KIM, IL HAN, LU, XIAOLIN
• Granted Patent: US 8,966,337 B2
• Time in Patent Office: Days
• US Class Current: 714/807
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: H03M 13/09 Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit

Abstract

A method of powerline communications including a first node and at least a second node on a powerline communications (PLC) channel in a PLC network. The first node sends a physical layer (PHY) data frame on the PLC channel including a preamble, a PHY header, a MAC header and a MAC payload. The MAC header includes a Cyclic Redundancy Check (CRC) field (MH-CRC field). The second node receives the data frame, parses the MAC header to reach the MH-CRC field, and performs CRC verification using the MH-CRC field to verify the MAC header. If the CRC verification is successful, (i) the second node parses another portion of the MAC header to identify a destination address of the data frame and (ii) to determine whether the data frame is intended for the second node from the destination address.

Claims

1. A method of powerline communications including a first node and at least a second node on a powerline communications (PLC) channel in a PLC network, comprising:

said first node sending a physical layer (PHY) data frame on said PLC channel comprising a preamble, a PHY header, a MAC header and a MAC payload, wherein said MAC header includes a Cyclic Redundancy Check (CRC) field (MH-CRC field);

said second node receiving said data frame, said second node;

parsing said MAC header to reach said MH-CRC field;

performing CRC verification using said MH-CRC field to verify said MAC header, and

wherein if said CRC verification is successful, (i) parsing another portion of said MAC header to identify a destination address of said data frame and (ii) determining whether said data frame is intended for said second node from said destination address.

2. The method of claim 1, wherein when said data frame is corrupted, further comprising said second node distinguishing corruption of said MAC header from corruption of said MAC payload, and said second node transmitting an acknowledgment (ACK) or negative acknowledgment (NACK) frame to said first node only when said CRC verification is successful, said determining determines said data frame is intended for said second node from said destination address, and said MAC payload is corrupted.

3. The method of claim 2, wherein said second node transmits said ACK or said NACK frame with said MH-CRC field within a PHY header of said ACK or said NACK frame.

4. The method of claim 1, wherein if said determining determines said data frame is not intended for said second node, said second node not decoding said MAC payload.

5. The method of claim 1, wherein if said CRC verification is successful, said second node setting its Network Allocation Vector (NAV) based on a frame transmission time indicated in said PHY header and transmitting on said PLC channel after an expiration of said NAV.

6. A modem for communications on a powerline communications (PLC) channel in a PLC network, comprising:

a processor;

wherein said processor is communicably coupled to a memory which stores a frame compiling algorithm including code for compiling data frames, and wherein said processor is programmed to implement said frame compiling algorithm, said frame compiling algorithm;

compiling a first physical layer (PHY) data frame comprising a preamble, a PHY header, a MAC header and a MAC payload, wherein said MAC header includes a Cyclic Redundancy Check (CRC) field (MH-CRC field), and

wherein said modem is configured for coupling to a PLC transceiver at a first node in said PLC network to provide said first data frame to said PLC transceiver so that said PLC transceiver transmits said first data frame over said PLC channel to at least a second node.

7. The modem of claim 6, wherein said modem is formed on an integrated circuit (IC) comprising a substrate having a semiconductor surface, wherein said processor comprises a digital signal processor (DSP).

8. The modem of claim 6, wherein said memory further stores a MH-CRC operating algorithm including code for responding to receiving a second data frame from said second node comprising a second preamble, a second PHY header, a second MAC header and a second MAC payload, wherein said second MAC header includes a second Cyclic Redundancy Check (CRC) field (second MH-CRC field), and wherein said processor is programmed to implement said MH-CRC operating algorithm, said MH-CRC operating algorithm operating on said second data frame, comprising the following regarding said second data frame:

parsing said second MAC header to reach said second MH-CRC field;

performing CRC verification using said second MH-CRC field to verify said second MAC header, and

wherein if said CRC verification is successful, (i) parsing another portion of said second MAC header to identify a destination address of said second data frame and (ii) determining whether said second data frame is intended for said first node from said destination address.

9. The modem of claim 8, wherein said MH-CRC operating algorithm further implements the following processing:

determining whether said second data frame is corrupted; and

distinguishing corruption of said second MAC header from corruption of said second MAC payload, and

transmitting an acknowledgment (ACK) or negative acknowledgment (NACK) frame to said second node only when said CRC verification is successful, said determining determines said second data frame is intended for said first node from said destination address, and said second MAC payload is corrupted.

10. The modem of claim 9, wherein said first node transmits said ACK or said NACK frame with said second MH-CRC field within a PHY header of said ACK or said NACK frame.

11. The modem of claim 9, wherein if said determining determines said second data frame is not intended for said first node, said MH-CRC operating algorithm not decoding said second MAC payload.

12. The modem of claim 8, wherein if said CRC verification is successful, said MH-CRC operating algorithm having said first node set its Network Allocation Vector (NAV) based on a frame transmission time indicated in said second PHY header and transmitting on said PLC channel after an expiration of said NAV.

13. A communications device for communications on a powerline communications (PLC) channel in a PLC network, comprising:

a memory which stores a frame compiling algorithm including code for compiling frames,

a modem coupled to said memory, said modem comprising;

a processor programmed to implement said frame compiling algorithm, said frame compiling algorithm compiling a first physical layer (PHY) data frame comprising a preamble, a PHY header, a MAC header and a MAC payload, wherein said PHY header includes a destination address field having a destination address therein, and

a PLC transceiver communicably coupled to said modem at a first node in said PLC network for transmitting frames including said first data frame over said PLC channel to at least a second node.

14. The communications device of claim 13, wherein said modem is formed on an integrated circuit (IC) comprising a substrate having a semiconductor surface, wherein said processor comprises a digital signal processor (DSP).

15. The communications device of claim 13, wherein said memory further stores a MH-CRC operating algorithm including code for responding to receiving a second data frame from said second node comprising a second preamble, a second PHY header, a second MAC header and a second MAC payload, wherein said second MAC header includes a second Cyclic Redundancy Check (CRC) field (second MH-CRC field), and wherein said processor is programmed to implement said MH-CRC operating algorithm, said MH-CRC operating algorithm operating on said second data frame, comprising the following:

parsing said second MAC header to reach said second MH-CRC field;

performing CRC verification using said second MH-CRC field to verify said second MAC header, and

wherein if said CRC verification is successful, (i) parsing another portion of said second MAC header to identify a destination address of said second data frame and (ii) determining whether said second data frame is intended for said first node from said destination address.

16. The communications device of claim 15, wherein said MH-CRC operating algorithm further comprises:

determining whether said second data frame is corrupted; and

distinguishing corruption of said second MAC header from corruption of said second MAC payload, and

transmitting an acknowledgment (ACK) or negative acknowledgment (NACK) frame to said second node only when said CRC verification is successful and said determining determines said second data frame is intended for said first node from said destination address, and said second MAC payload is corrupted.

17. The communications device of claim 16, wherein said first node transmits said ACK or said NACK frame with said second MH-CRC field within a PHY header of said ACK or said NACK frame.

18. The communications device of claim of claim 16, wherein if said determining determines said second data frame is not intended for said first node, said MH-CRC operating algorithm not decoding said second MAC payload.

19. The communications device of claim 15, wherein if said CRC verification is successful, said MH-CRC operating algorithm setting a Network Allocation Vector (NAV) based on a frame transmission time indicated in said second PHY header for said first node to transmit on said PLC channel after an expiration of said NAV.