A Method of Physical Layer Network Coding Packet Synchronization

Abstract

A physical layer network coding package synchronizing method of the invention comprises the following steps: at the beginning of a time slot, a node x sends an RTS frame carrying address information of a destination node y to a relay node; the relay node broadcasts a CTS frame to the node x and the node y, and records the timestamp t1 at the moment; the node x returns an N-PNC frame to the relay node, and the relay node R records a received timestamp t2; the node y waits for a long enough period of time delta and then returns an N-PNC frame to the relay node after receiving the CTS frame broadcast by the relay node, and the relay node records a timestamp t3 for receiving the N-PNC frame; and the relay node obtains the propagation delay from the node x to the relay node and the propagation delay from the node y to the relay node, and the node x and the node y respectively send a data packet to the relay node R after waiting, and therefore the two data packets sent by the node x and the node y arrive at the relay node R at the same time, and package synchronization is realized. According to the invention, synchronization of all nodes in a network is not needed, while the time of the relay node is used as the benchmark. Thus, the complexity of system synchronization is greatly reduced.

Description

technical field [0001] The invention relates to a method for synchronizing physical layer network coding packets. Background technique [0002] Physical layer network coding (PNC) has attracted increasing attention due to its ability to improve the throughput performance of relay-assisted systems. However, the practical application of PNC is a difficult process, and synchronization is one of the important and difficult problems encountered. Because the core idea of ​​physical layer network coding is to use the superposition of two signals transmitted at the same time to improve network throughput. In order for the relay node to map the superimposed signal correctly, the PNC requires that the two original signals to be superimposed be strictly synchronized, otherwise errors will occur. However, due to the different distances and channel states between the two user nodes performing PNC communication and the relay node, the data packets sent by them may not arrive at the rela...

AI Technical Summary

Problems solved by technology

However, due to the different distances and channel states between the two user nodes performing PNC communication and the relay node, the data packets sent by them may not arrive at the relay node at the same time

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