Research On Multi-Layer Fusion Location Technology Of Underwater Acoustic Sensor Network Based On MAC Protocol

The location technology of underwater sensor networks is an important foundation for marine development and utilization.The underwater acoustic localization algorithm can be divided into the Range-based location algorithm and the Range-free location algorithm.Compared with the Range-based location algorithm,the Range-free location algorithm only uses the connectivity of the network to locate.Therefore,the Range-free algorithm is more energy efficient and more suitable for underwater acoustic sensor network communication.Among them,the Centroid location algorithm and the APIT location algorithm are widely used due to their simple algorithm.In order to improve the location accuracy of the Range-free algorithm,a higher node density is usually required,which undoubtedly increases the collision rate and the energy consumption.In response to this phenomenon,this paper proposes a multi-layer fusion location research scheme for underwater acoustic sensor networks(UWSNs)based on MAC protocol.The main work and innovation of the thesis are as follows:1.The traditional APIT algorithm can obtain higher location accuracy with less control overhead,but it has larger redundancy error.Therefore,an improved APIT location algorithm is proposed,named IAPIT location algorithm.The IAPIT algorithm defines the selection range of neighbor nodes and uses a more objective point-scanning method to determine the largest area where the sensor node may be in.Finally,the performance of the algorithm is analyzed by simulation under the OPNET.2.In order to solve the additional collisions due to the high node density of the Range-free location algorithm,this paper considers the use of the underwater acoustic MAC protocol.Considering the limited energy and computational power of the underwater acoustic sensing network,a slotted ALOHA(QS-ALOHA)protocol based on Q learning algorithm is proposed.The protocol combines the Q learning algorithm,slotted ALOHA,and a binary exponential backoff algorithm(BEB).Simulations show that the QS-ALOHA protocol can not only improve system throughput,reduce end-to-end delay,but also adapt to network topology changes.3.The paper builds a cross-layer location model on the OPNET platform,and analyzes the performance of the Range-free algorithm under the MAC protocol.The simulation results show that selecting the appropriate MAC protocol according to the location algorithm can improve the location accuracy and energy efficiency of the Range-free location algorithm.