Wireless Sensor Network Communication Mechanism

Wireless Sensor Network (WSN) is a kind of self-organization network formed through wireless communication, which is composed with a plenty of small nodes. It can perceive, collect and process the objects perceived in network coverage areas, then send the results to observers. As a new technology for information perception and processing, Wireless Sensor Network integrated of sensor technology, wireless communication technology and embedded technology attracts numbers of exports and scholars whether at home or abroad. Wireless Sensor Network gradually becomes a new research hotspot, because of its broad application prospects in fields such as military, industry, agriculture, environmental science and smart home, and so on.At present, wireless Sensor Network is still in the study, which aims to server our daily life and production as soon as possible. The extensive research of Wireless Sensor Network on the network architecture, hardware platform design, software platform design and organization of the network promotes the development of Wireless Sensor Network technology in all aspects. Communication mechanism is the key for wireless sensor nodes to exchange data, any research or development will greatly enhance the performance of Wireless Sensor Network. So, this thesis does an in-deep research on both wireless communication mechanism and UART communication mechanism, in the development background of WSN node project which is an important part of the China's Next Generation Internet (CNGI).The achievements in this thesis are as follows:The first one: the concept, network architecture and the features of Wireless Sensor Network are generally introduced. Besides, this thesis does a deep research on our hardware platform design and operation system design based on this hardware platform.The second one: this thesis does a detailed analysis of wireless communication protocol stacks on the basis of IEEE802.15.4 data link layer protocol, which applies to low power personal LAN (LR_PLAN).Besides, the thesis propose the implement of the non-timeslot CSMA\CA channel access mechanism with the communication module of CC2420.Finally and studies a simple type of route arithmetic of network layer and the implement of active message communication mechanism. The third one, the thesis does research on UART communication between the gateway and Sink node and implement of a ppplike communication protocol.The last one, thinking of the importance of energy in WSN, this thesis studies and implement the energy-saving strategy used by different levels of energy-saving architecture after the detailed analysis of the energy-saving architecture in the whole WSN system. Then, an energy-saving algorithm based on timeslot is proposed, which is integrated of the principle of adaptive power control and is applied to TARAX platform.