Distributed Beamforming Technology In Underwater Acoustic Sensor Network

Distributed beamforming technology is to use idle transmitting nodes as virtual elements to form a virtual array.A beam forming vector is set up for each transmitting element to form a directional beam to assist other nodes in data transmission.The technology can also achieve directional transmission of signals,increase channel ca-pacity,improve signal to noise ratio and reduce the possibility of interception.Be-cause of the advantages of distributed beamforming,the technology is playing an in-creasingly important role in wireless communication,ocean exploration,seismic ex-ploration and other fields.In order to reduce the bit error rate of received signals in the underwater sensor network and expand the communication range of the whole network,this paper pro-poses to apply distributed beamforming technology to the communication of the un-derwater sensor network.Aiming at the problem of phase unsynchronization caused by the random distribution of each sensor position in distributed beamforming tech-nology,this paper proposes a phase adjustment algorithm with no feedback and feed?back information to obtain the synchronous phase.To solve the problem of high bit error rate of received signals when sensor nodes transmit information with noise,this paper proposes the optimal power setting strategy of sensor nodes to obtain the opti-mal SNR of received signals.The main work of this paper is summarized as follows:(1)To study the beamforming technology and the principle of distributed beam-forming technology,combined with the characteristics of underwater acoustic sensor networks,distributed beamforming technology application environment,the proposed distributed beamforming technology is used in underwater sensor network,make full use of idle nodes in network collaboration other nodes for data transmission.(2)This paper proposes to use"improved round-trip synchronization algorithm"in conjunction with"phase synchronization algorithm of feedback information"to solve the phase synchronization problem in distributed beamforming technology.Ac-cording to the characteristics of slow underwater propagation of sound waves,the"phase synchronization algorithm of feedback information"is improved to speed up the phase synchronization.Finally,MATLAB software is used for simulation analysis.(3)This paper proposes the power selection strategy of distributed beamforming technology to solve the problem of high bit error rate when there is interference in the forwarding signal of the forwarding node.Two alternative algorithms are proposed,,Switching algorithm based on feedback information"and"Control algorithm based on channel information".The characteristics,application range and application condi?tions of the two algorithms are analyzed.Finally,MATLAB software is used to simu-late the two algorithms.