Robust line coding scheme for communication under severe external noises
A system to implement a communication line coding scheme using a non-complex bit-to-symbol mapping, a forward error correction (FEC) coding, and an additive bit scrambler after the FEC at the PHY layer is provided. The system may be a part of or implemented by an automobile component. The system may be a PHY device configured to convert data from the MAC layer into 2D-PAM3 symbols that are transmitted across a communication link at a predetermined transmission rate, such as to be compliant with a communication standard. The PHY device may select characteristics of the conversion, such as the FEC coded symbol, based on the target transmission rate. The PHY device may include a transceiver, and may convert the data from MAC layer to PHY layer and back.
1. A system comprising:
a media independent interface circuitry configured to receive, from an automobile component, binary data and corresponding management information to be transmitted via a communication link;
an encoder circuitry configured to generate forward error correction (FEC) frames that contain the binary data and the management information; and
a communication interface circuitry configured to transmit the FEC frames that contain the binary data and the management information via the communication link.
2. The system of claim 1 , further comprising:
a scrambler circuitry configured to scramble the FEC frames exclusive of the management information; and
a data mapper circuitry configured to convert the scrambled FEC frames into pulse amplitude modulation (PAM) symbols according to a predetermined conversion scheme, wherein the communication interface circuitry is configured to transmit the FEC frames via the communication link by transmitting the PAM symbols via the communication link.
3. The system of claim 2 , wherein the predetermined conversion scheme converts a predetermined amount of binary data from the scrambled FEC frames into a corresponding predetermined number of PAM symbols.
4. The system of claim 3 , wherein conversion of the predetermined amount of binary data to the corresponding predetermined number of PAM symbols comprises mapping 3 binary bits into 8 pairs of voltage levels based on a 2D-PAM3 constellation.
5. The system of claim 1 , further comprising:
a data mapper circuitry configured to convert the FEC frames into pulse amplitude modulation (PAM) symbols according to a predetermined conversion scheme, wherein the communication interface circuitry is configured to transmit the FEC frames via the communication link by transmitting the PAM symbols via the communication link.
6. The system of claim 1 , wherein the encoder circuitry determines a size of each FEC frame from the generated FEC frames, and the size is based on a predetermined transmission rate over the communication link.
7. The system of claim 1 , further comprising:
a physical coding sublayer (PCS) framer circuitry configured to generate a PCS frame, the PCS frame comprising a predetermined number of bits of the binary data appended with a corresponding header information.
8. The system of claim 7 , wherein the encoder circuitry is further configured to:
aggregate a first predetermined number of PCS frames from the PCS framer circuitry; and
generate a second predetermined number of FEC frames corresponding to the first predetermined number of PCS frames from the PCS framer circuitry.
9. The system of claim 8 , wherein the encoder circuitry is further configured to generate parity check frames corresponding to the second predetermined number of FEC frames.
10. The system of claim 9 , wherein the encoder circuitry is further configured to generate a management FEC frame comprising the management information.
11. A system comprising:
a physical media communication interface configured to receive data from an automobile component over a physical media;
converter circuitry configured to convert the data into a forward error correction (FEC) frame that comprises a plurality of symbols;
decoder circuitry configured to decode, from the plurality of symbols, a plurality of data symbols and a management symbol; and
a media independent interface configured to transmit the plurality of data symbols and the management symbol to another automobile component for further processing.
12. The system of claim 11 , wherein the received data is a two-dimensional pulse amplitude modulation (PAM3) symbol using a nine-point constellation.
13. The system of claim 11 , wherein the physical media is a two conductor cable.
14. The system of claim 11 , wherein the decoder circuitry comprises a Reed-Solomon decoder configured to generate data symbols of a predetermined size.
15. The system of claim 14 , wherein a length of a data symbol is determined based on a predetermined transmission speed of the system.
16. The system of claim 11 , wherein the received data comprises ternary data and the converter circuitry further comprises:
data de-mapper circuitry configured to convert the ternary data into binary data based on a predetermined mapping scheme; and
de-scrambler circuitry configured to convert the binary data into the forward error correction (FEC) frame.
17. The system of claim 16 , wherein the data de-mapper circuitry is further configured to aggregate a predetermined number of ternary data symbols prior to conversion of the aggregated ternary data symbols into binary data based on the predetermined mapping scheme.
18. A method comprising:
generating, by a physical coding sublayer (PCS) framer circuitry, PCS blocks based at least in part on received MAC layer data;
aggregating, by an encoder circuitry, a predetermined number of PCS blocks and operations, administration, and maintenance (OAM) bits to generate aggregated PCS blocks;
scrambling, by a data scrambler circuitry, the aggregated PCS blocks to generate scrambled aggregated PCS blocks, wherein the data scrambler circuitry does not scramble the OAM bits of the aggregated PCS blocks; and
transmitting the aggregated scrambled PCS blocks via a communication link.
19. The method of claim 18 , further comprising:
generating, by a data mapper, pulse amplitude modulation (PAM) symbols corresponding to the aggregated scrambled PCS blocks, wherein transmitting the aggregated scrambled PCS blocks via the communication link comprises transmitting the PAM symbols via the communication link.
20. The method of claim 18 , further comprising:
generating, by the encoder circuitry, forward error correction (FEC) frames comprising the aggregated scrambled PCS blocks; and
generating, by a data mapper, pulse amplitude modulation (PAM) symbols corresponding to the FEC frames, wherein transmitting the aggregated scrambled PCS blocks via the communication link comprises transmitting the PAM symbols via the communication link.