Design And Implementation Of Physical Layer Of Dedicated Multi-node Broadband Wireless Communication Network

With the continuous improvement of space science and technology,the world’s major spacefaring nations have joined the camp of manned deep space exploration to further explore the unknown areas of mankind.Taking lunar exploration as an example,China’s lunar exploration project has now achieved point-to-point communication between probes on the lunar surface.With the full-scale lunar surface exploration activities in the future,the number of nodes involved in the mission will gradually increase,requiring multiple lunar surface exploration nodes(astronauts,lunar rovers or robots,etc.)to work together to efficiently complete the exploration mission,and thus multi-node communication networks need to be designed to support it.At present,domestic and international research is still in the exploration stage regarding what kind of communication network should be used for multi-nodes in interplanetary exploration missions.In this thesis,the physical layer link of a dedicated multi-node broadband wireless communication network is designed to achieve data communication among multiple nodes under the resource and energy constraint in response to the communication requirements of multi-target,multi-service,multi-type and high speed of the extraterrestrial surface exploration mission.This thesis is an overall description of the completed design and implementation work.The thesis first presents the design scheme of the dedicated multi-node communication network based on Orthogonal Frequency Division Multiplexing(OFDM).The system channels are divided into two types: broadband shared channels and narrowband dedicated channels,and the Time Division Multiple Access(TDMA)and Orthogonal Frequency Division Multiple Access(OFDMA)transmission regimes are adopted respectively.OFDMA)transmission systems.Based on the analysis of interference characteristics of multi-user OFDMA system,the design of time slot frame structure,carrier allocation scheme and frequency guide sequence is completed.In addition,a complete transceiver transmission scheme for a dedicated multinode broadband wireless communication system is presented.Taking the uplink shared channel as an example,the principle,method and implementation of the transmitter baseband communication signal generation are analyzed in detail,and the algorithms of the main key technologies in the receiver,such as timing synchronization,carrier frequency synchronization and channel estimation,are analyzed and their implementation is described in detail.Finally,an end-to-end communication simulation model based on the Simulink platform is built for different types of communication links,and the written Register Transfer Level(RTL)code for the physical layer of the transceiver link is tested by large-scale co-simulation to verify the correctness of the code in terms of functionality and computational accuracy.Based on the hardware platform consisting of Xilinx’s ZC706 development board(core device is XC7Z045)and ADRV9371-W RF module,multiple transmission modes for different types of channels of a dedicated multi-node broadband communication network system are tested on board.The hardware test results show that the designed physical layer transmission module can successfully achieve normal communication between multiple nodes in different modes,and all functions meet the design requirements.