High-speed And Low-power Wireless Sensor Network Data Transmission Technology Research And Design

Wireless sensor networks generally used totransmitting information, such as temperature and humidity. When transferring images, audio and video and other multimedia data, not only the transfer rate gets attention, but also further highlights its node energy consumption and timeliness of information transmission problems. In Sensor network protocol stack, MAC layer directly controls the wireless RF moduleand the protocol design directly affects the energy consumption of nodes and data transmission timeliness, therefore it is an important part of the sensor network research.This paper againstthe challenge that the traditional wireless sensor network are facing, when transfer large amounts multimedia information, based on the analysis of the MAC protocol, research is doing on the perspective of an asynchronous MAC protocol.In wireless sensor networks, the existing receiver-initiated MAC protocol based on asynchronous duty cycling, are almost using pseudo-random wakeup schedule of neighbor nodes, in predicting the receiving node wakeup time. In the application of the transmission of multimedia information, load conditions in the network is dynamic, this method can’t change the wakeup interval of node dynamically, and lead to higher data conflict rates while transmitting and larger data transmission delay. To solve this problem, the paper presents HELD-MAC (High energy efficiency and Low delay MAC), a new protocol that can ensure a different wakeup time between the nodes and predicate the wakeup time of receiving node accurately. The protocol can change the wakeup interval of node dynamically according to the load conditions. Meanwhile, in order to alleviate the problem of energy hole, the protocol can adaptively change the lowest node wakeup interval according to the residual energy of the node. Through simulation, HELD-MAC protocol has obvious advantages in the performance of data transmission delay, power consumption, networks throughput and transmission collision, compared with RI-MAC and PW-MAC protocols.The average data transmission delay and the average duty cycle of HELD-MAC is less than RI-MAC81.2%,19.5%respectively and less than PW-MAC11.2%,10.1%. HELD-MAC protocol is more suitable to large number of transmission and the transmission time-demanding wireless sensor network applications compared with others.