Coexistence primitives in power line communication networks
Systems and methods for setting a carrier-sensing mechanism in a PLC node are disclosed. In a PLC standard, coexistence is achieved by having the nodes detect a common preamble and backing off by a Coexistence InterFrame Space (cEIFS) time period to help the node to avoid interfering with the other technologies. In one embodiment, a PHY primitive is sent from the PHY to the MAC know that there has been a preamble detection. A two-level indication may be used—one indication after receiving the preamble and other indication after decoding the entire frame. The MAC sets the carrier-sensing mechanism based on the preamble detection.
1. A method, comprising:
performing by a power line communication (PLC) device of a first PLC communication standard type:
detecting a coexistence preamble on a PLC channel, wherein the co-existence preamble includes a sequence of symbols that is detectable by both PLC devices of the first PLC communication standard type and PLC devices of a second PLC communication standard type that is different from the first PLC communication standard type;
configuring a preamble indication primitive in a first format if a native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble, wherein the native preamble for the first PLC communication standard type is detectable by PLC devices of the first PLC communication standard type but not by PLC devices of the second PLC communication standard type;
configuring the preamble indication primitive in a second format if the native preamble for the first PLC communication standard type is not detected in addition to the coexistence preamble;
setting a carrier-sensing mechanism based upon the preamble indication primitive; and
sending the preamble indication primitive from a PHY layer to a MAC layer on the PLC device.
2. The method of claim 1 , further comprising:
setting the carrier-sensing mechanism to a first interframe spacing value if the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble; and
setting the carrier-sensing mechanism to a second interframe spacing value if the native preamble for the first PLC communication standard type is not detected in addition to the coexistence preamble.
3. The method of claim 1 , further comprising:
setting the carrier-sensing mechanism to a native extended interframe spacing (EIFS) value for the first PLC communication standard type, if the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble; and
setting the carrier-sensing mechanism to a coexistence extended interframe spacing (cEIFS), if the native preamble for the first PLC communication standard type is not detected in addition to the coexistence preamble.
4. The method of claim 1 , wherein the coexistence preamble comprises an integer number of repeated symbols agreed upon between the first PLC communication standard type and the second PLC communication standard.
5. The method of claim 4 , wherein the repeated symbols include OFDM symbols.
6. The method of claim 4 , wherein the repeated symbols include one or more of a chirp sequence, a pseudo-random bit sequence, a barker sequence, and an arbitrary +1/−1 sequence.
7. A power line communication (PLC) device of a first PLC communication standard type comprising:
a receiver configured to monitor a power line communication (PLC) channel of a PLC network and to perform a preamble detection operation on the PLC channel;
a medium access control (MAC) layer adapted to receive a preamble indication primitive from the PHY layer;
a carrier-sensing mechanism adapted to be set by the MAC layer based upon the preamble indication primitive; and
a physical (PHY) layer adapted to configure a preamble indication primitive, the preamble indication primitive being configured in a first format if a native preamble for the first PLC communication standard type is detected by the receiver in addition to a coexistence preamble, and the preamble indication primitive being configured in a second format if the native preamble for the first PLC communication standard type is not detected in addition to the coexistence preamble;
wherein the co-existence preamble includes a sequence of symbols that is detectable by both PLC devices of the first PLC communication standard type and PLC devices of a second PLC communication standard type that is different from the first PLC communication standard type; and
wherein the native preamble for the first PLC communication standard type is detectable by PLC devices of the first PLC communication standard type but not by PLC devices of the second PLC communication standard type.
8. The PLC device of claim 7 , wherein:
the carrier-sensing mechanism is set to a first interframe spacing value if the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble; and
the carrier-sensing mechanism is set to a second interframe spacing value if the native preamble for the first PLC communication standard type is not detected in addition to the coexistence preamble.
9. The PLC device of claim 7 , wherein:
the carrier-sensing mechanism is set to a native extended interframe spacing (EIFS) value if the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble; and
the carrier-sensing mechanism is set to a coexistence extended interframe spacing (cEIFS) if the native preamble for the first PLC communication standard type is not detected in addition to the coexistence preamble.
10. The PLC device of claim 7 , wherein the coexistence preamble comprises an integer number of repeated symbols agreed upon between the first PLC communication standard type and the second PLC communication standard.
11. The PLC device of claim 10 , wherein the repeated symbols include OFDM symbols.
12. The PLC device of claim 10 , wherein the repeated symbols include one or more of a chirp sequence, a pseudo-random bit sequence, a barker sequence, and an arbitrary +1/−1 sequence.
13. A method, comprising:
performing by a power line communication (PLC) device of a first PLC communication standard type:
determining whether a native preamble for the first PLC communication standard type or a non-native preamble that is not the native preamble for the first PLC communication standard type is detected after a coexistence preamble on a PLC channel;
configuring a preamble indication primitive in a first format if the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble;
configuring the preamble indication primitive in a second format if the non-native preamble that is not the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble;
setting a carrier-sensing mechanism based upon the preamble indication primitive; and
sending the preamble indication primitive from a PHY layer to a MAC layer on the PLC device;
wherein the co-existence preamble includes a sequence of symbols that is detectable by both PLC devices of the first PLC communication standard type and PLC devices of a second PLC communication standard type that is different from the first PLC communication standard type;
wherein the native preamble for the first PLC communication standard type is detectable by PLC devices of the first PLC communication standard type but not by PLC devices of the second PLC communication standard type; and
wherein the non-native preamble that is not the native preamble for the first PLC communication standard type is not detectable by PLC devices of the first PLC communication standard type.
14. The method of claim 13 , further comprising:
setting the carrier-sensing mechanism to a first interframe spacing value if the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble; and
setting the carrier-sensing mechanism to a second interframe spacing value if the non-native preamble that is not the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble.
15. The method of claim 13 , further comprising:
setting the carrier-sensing mechanism to a native extended interframe spacing (EIFS) value if the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble; and
setting the carrier-sensing mechanism to the coexistence extended interframe spacing (cEIFS) if the non-native preamble that is not the native preamble for the first PLC communication standard type is detected in addition to the coexistence preamble.
16. The method of claim 13 , wherein the non-native preamble that is not the native preamble for the first PLC communication standard type is the native preamble for the second PLC communication standard that is detectable by PLC devices of the second PLC communication standard type but not by PLC devices of the first PLC communication standard type.