Relay method and nodal point of power line communication

Abstract

The invention discloses a relay method and a nodal point of power line communication. The method includes judging whether the target address in a data frame is matched with the address of the nodal point or not after receiving the data frame. The data frame carries the target address, relay hopping times and sent times. If the target address in a data frame is not matched with the address of the nodal point, the method determines whether the data frame satisfies the forward condition. The transfer condition at least comprises that the data frame is not sent and the forwarded times is smaller than the relay hopping times. If the data frame satisfies the forward condition, the forwarded times in the data frame is added by 1 sequentially according to broadcast times and are broadcasted. The broadcast times is obtained by calculating the relay hopping times, the forwarded times in the data frame and the largest sending times of the nodal points, and the largest sending times is larger than the relay hopping times. The relay method and the nodal point improve successful ratio of the power line communication while not sacrificing communication time by combining repeated sending with the flooding technology.

Description

technical field [0001] The invention relates to the communication field, in particular to a relay method and node for power line communication. Background technique [0002] Power line carrier communication is a method of using power lines to transmit information. It uses power line networks as the transmission medium. It has the characteristics of low cost and low construction difficulty, and can be widely used in automation control, broadband access and other fields. [0003] But powerline networking is not a reliable communication medium. First of all, the power line will cause strong attenuation to the communication signal: the amount of attenuation depends on the signal frequency, network topology, load electrical appliances, etc. Due to many influencing factors, the attenuation characteristics of the power line are very complicated, showing the characteristics of frequency selective fading, for example Deep grooves are formed at certain frequencies. Secondly, electri...

AI Technical Summary

Problems solved by technology

The problem with this method is: (1) The source node must know the quality of the communication links between the nodes in the network, and maintain a routing table to record this information, which has high requirements on the computing power and storage capacity of the nodes , increases the system cost, and in some cases even cannot be realized; (2) The power line channel is time-varying, the communication quality between nodes varies with time, and the source node must constantly update the The quality of the communication link will increase the overhead of network throughput and reduce the effective bandwidth; (3) The network conditions mastered by the source node may not match the current power line network conditions. Since the power line channel is time-varying, the originally designated communication path has been Changes will cause communication failure at this time, and the source node must try other paths, which increases the time required for a successful communication, or increases the frame delay; (4) it takes time to establish a routing table, when the number of nodes is large Or when the communication rate is limited, the time required to build the routing table will be unacceptably long

For this random and time-varying topology, flooding may not be able to traverse all possible paths, so the communication success rate is still unsatisfactory in practical applications

Although the strategy of timeout retransmission can be used to improve the success rate, it is clear that the speed of the timeout retransmission strategy will greatly increase the communication time

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