Study On Full-duplex Communication For Low Voltage Power Line Network

Low voltage power line communication is unique and future development prospect of the communication. At present chip domestic carrier demodulation technology goes hand in hand. There is no quality difference, but the performance difference is very big still. The key is to see how to deal with sending and receiving way. There is no bad modulation technology, only the implementation of the algorithm. Chip without the MAC layer due to the existing carrier function, need software to realize, and low communication rate and time-varying communication conditions, so the carrier check when listening to no node using the network, the actual carrier is other node mapping is online, but has not yet arrived or not to listen. These reasons lead to networking time is too long, if the network in addition to the beacon frame, there are other data frame, the problem becomes more complicated. According to the above problem, this paper proposes low-voltage power line full-duplex communication network model, to improve the efficiency of networking and communications.First, this paper comprehensively expounds the transmission properties of low-voltage power line channel, interference and attenuation characteristics, and the complexity of the low-voltage power line network topology structure and real time, points out that the network function of low voltage power line communication network and network requirements. Points out that the existing modulation demodulation chip on one phase of three-phase power, using the same frequency half duplex communication, so in this way, even with the relatively advanced distributed networking and dynamic clustering routing algorithm, the MAC layer of the coordination and control mechanism is very complex, result in network time is too long. Low voltage power line full-duplex communication system model is to provide the basis for the follow-up study.Then, low-voltage power line full-duplex communication network based on TCP/IP networking method can make the same phase and reliable communication by low voltage power line communication nodes constituting an IP subnet. Not reliable communication nodes and points belong to different subnets rely on communication subnet gateway between nodes. The gateway node between the two subnets are composed of multiple nodes gateway cluster, achieve the goal of reliable communication. At the same time by making appropriate routing algorithm can guarantee the stability of low-voltage power line communication network and make communication anti-destroying ability better than traditional star network topology and set up network communication model based on OPNET software simulation.Finally, for the low voltage power line user terminal works with half-duplex and full-duplex difference, lead to resource use on a power line channel belong to single channel, another belongs to dual channel. Using queuing theory, the corresponding network performance model is a single server queue, the other one is double the server queue. Both queuing network model was constructed based on the OPNET platform, gives analysis to the performance evaluation, by verifying known of low-voltage power line full-duplex communication network performance is optimal.