Design And Research For The Algorithm Of BAN Physical Layer Baseband

BAN has become an important means to solve the problem of remote medical diagnosis, mobile clinic, health assessment and consultation, community health care and other medical and healthy fields. The proposition of 802.15.6 protocol has greatly promoted the development of BAN technology, but it lacks of a complete BAN baseband system. Therefore, the research on BAN baseband is of great significance. In this thesis, the BCH code is used as the channel coding mode of the communication system. A relatively simple spreading, scrambling algorithm is designed. Phase finding methods is proposed to achieve ?/2-DBPSK modulation, and the baseband differential detection is used to demodulate. According to the characteristics of data structure of PLCP leader sequence, packet detection, symbol synchronization and carrier frequency synchronization algorithm are designed. After completing the design of each module, the physical layer of BAN is simulated. Simulation results show that the signal to noise ratio is less than 13 d B and the SNR is less than 10-5, which meets the requirement of the system.Protecting security of vital signs information is a very important technical requirement in the BAN implementation process. This project aims to the characteristics of the BAN system architecture and presents a data security scheme based on electrocardio characteristics parameters. The main research contents include designing the filter of electrocardio signal and recognizing QRS waves, and investigating methods of the circuit-level data encryption and dynamic key refreshment due to obtained electrocardio signal characteristic value parameters. The proposed scheme is constructed from the inherent features of the BAN system, adopts vital information form security protection, balances the calculation complexity of the sensor nodes and smart terminal, which has advantages of high strength, low cost and easy implementation, and is very useful to design low-power sensor nodes and provide theoretical support and engineering implementation for forming the BAN standard system.