Design And Implementation On Physical Layer Data Link Of High-Performance Mobile AD Hoc Network

Wireless Ad-hoc Network is independent of wired infrastructure,and has the advantages of rapid deployment,flexible extension and strong persistence,etc.It is widely applied in the fields of military and civilian communications such as emergency security,assault deployment and disaster relief,as well as has become an essential research direction of modern wireless communication technology.The design and implementation of High-performance Mobile Adhoc Network(HpMANET)suitable for a variety of application scenarios is a significant direction of technical research and development in this field at present.The thesis focuses on the data bearer link of HpMANET physical layer to carry on the specific design and implementation,which includes the following main work:(1)Starting from the functional characteristics of the research and development system,the design of frequency domain structure and time domain frame structure in the physical layer transmission is researched and confirmed,aiming at the application requirements of wide bandwidth,high rate,low delay and high quality.Furthermore,a detailed design for the signal processing process of the data bearer link is given emphatically.(2)In order to meet the requirements of the physical layer data link receiving detection system for high speed,high reliability and low delay,iterative detection of soft input and soft output in channel coded wireless transmission system is researched in depth,together with auxiliary detection method of lattice reduction in free channel coding system.From the iterative detection technology,the low complexity filtering based on QR decomposition and the low complexity soft demodulation method based on max-log algorithm are put forward.For the high implementation complexity problem caused by the uncertain execution time and cycle number of LLL lattice reduction detection,the fixed complexity reduction algorithm is put forward,and the QR decomposition algorithm is sorted jointly for the signal detection.The analysis results of the performance simulation and the complexity indicate that these two detection schemes have lower complexity and provide good bit error performance.(3)With regard to the development platform and the supporting tools adopted in the project,HLS tools are researched and used for the specific hardware implementation to the designed data link receiving detection system.The computing simulation and the statistical analysis are utilized to the fix-point scheme design for the key processing function module in the algorithm,and the HLS optimized function instruction is applied for specific function module to realize the structural optimization.Moreover,the look-up table and the linear fitting are combined to realize the optimization treatment for the division operation which algorithm process takes a relatively long time.The result of system integration verification shows that the developed receiving detection system has correct functions,which meets the requirements of physical layer data link,and it is of positive value to the technical design and the application development of HpMANET system.