A Simplex Communication Technology Research Used For Underwater Timing And Navigation

With the enormous development in the field of marine technology,underwater platforms with capacity for long-term operation or large area mobility have shown their outstanding contributions for the applications such as coastal defense,marine resource survey,underwater environment monitor,etc.To those kinds of underwater platforms,exactly timing and precisely navigation are not only the need to meet their functional operation but also the guarantee for the safety of themselves.Therefore,it is of great importance for the design of underwater navigation station.The application meaning attributes to the consideration of the simplex mode broadcasting for the underwater silence agents to access.Firstly,this thesis explores the scheme of underwater position navigation and time servicing,with the assumption of simplex mode broadcasting communication.Some user features and system compositions learn for the radio navigation station in the air,but most of the research are devoted to the consideration for the actual application underwater environment: channel complexity,large propagation delay,concealment,etc.An integrated solution to the underwater time servicing and position navigation is presented.According to this plan,the key technologies and error factors are analyzed.Secondly,address to the issue on the underwater navigation,the key technique,the simplex broadcasting communication technology,this thesis simulated the communication scheme.The codes transplant from the platform of PC to DSP TMS320C6713 platform.Real time encoding and decoding are verified through the electrical debug in simulated channel condition with the inducing of additive noise and multipath effect.Besides these,some sections discuss the concealment design in three aspects : the encryption,preventing exposure and low intercept.Finally,to test the performance of the communication algorithm,experiments have been carried out in Qiandao Lake,ZheJiang province and Lianhua lake,Hei LongJiang province,separately.During these trials,information series are transmitted in real time.Received signals are sampled and storage to disk.The results show that communication algorithm has some adaptability for different areas,different working conditions.Thus,it provides the necessary reference to the design of the system for nderwater navigation station,based on simplex broadcasting communication.