Efficient Neighbor Discovery Based On Stacked Signal Strength In Wireless Networks

Wireless networks play a decisive role in the Internet of Things,and wireless networks in smart homes are more of wireless sensor networks.When designing their protocols,energy consumption must also be considered.An important protocol in the wireless network protocol family is the neighbor discovery protocol.Its purpose is to quickly and efficiently discover neighbor nodes within the communication range,thereby providing important neighbor node information for other protocols.The collision of packets will greatly affect the performance of the neighbor discovery protocol.When considering the conflict,the existing neighbor discovery protocols basically study how to reduce the probability of collision,or in some occasions where the delay requirement is high,corresponding mathematical models will be established to explore how to design protocols to minimize the mathematical expectation of delay.The consensus of this type of protocol is that when a conflict occurs,the packet information cannot be used and must be retransmitted.This article believes that although the data of the packet cannot be used during the collision,the node can perceive the energy of the packet,especially the energy of the collision has a significant superposition effect,which will make the energy present a certain waveform.If the way of sending the packet is deliberately controlled,the rule of the energy waveform is related to the node's ID,and the neighbor's ID can be inferred from the energy waveform,so as to achieve the purpose of neighbor discovery.In order to achieve this goal,this article has proposed two protocols,one of which is binding of the node's ID and the packet length(method one),and the other is binding of the node's ID and the packet length and energy(method two).Binding means that for the node with ID n,when other nodes find it,the length of the data packet it sends is n,and the energy is also n.The article analyzes the two protocols separately and calculates their discovery probabilities.The conclusion is that method two has better discovery effect.The article first proposed the algorithm 1 to analyze the energy waveform according to the general situation,and then based on several special situations that may exist,because algorithm 1 is not applicable,and further proposed algorithm 2,algorithm 3 and algorithm4,respectively,the complexity of which increased in turn.Depending on the computing power of the node,the sensitivity to energy perception,and the probability of a special situation,different algorithms should be selected.When actually conducting experimental verification,we chose algorithm 1 and algorithm 2.In the experimental part,it first analyzes and introduces how the node obtains the RSSI of the environmental noise,lays the foundation for the subsequent experiment,then tests the effect of the distance of the neighbor nodes,and then compares the difference in the probability of discovery between method 1 and method 2 respectively.After we find method 2 is better than method 1,we do experiments to analyze the influence of node's ID selection on the probability of discovery.Because the core of the protocol is to change the way of neighbor discovery-from receiving packets to analyzing energy waveforms for discovery,the final experiment is to compare its delay with the Quorum protocol,and the conclusion is that when the number of conflicting neighbor nodes is less than 4,the delay performance is improved.