The Research Of Energy-efficient MAC Protocol In WSN Based On Report Service

In recent decades, wireless sensor networks has been widely studied andapplied.Until today, the main problem of wireless sensor network is still the limitedenergy supply, which because nodes are supplied with battery. Existing researchesmainly focus on MAC protocols, routing protocols and networking to reduce the energyconsumption of wireless sensor networks and increase network lifetime. This paper westudy DMAC, which is an energy-efficient MAC protocol, and analyse its problems. Tosolve its problems, we propose STSA-MAC、 BSTSA-MAC、 MSTSA-MAC、BMSTSA-MAC protocol to save energy and reduce transmission delay.The main application of WSN is that sensor nodes collect sensor data and sendthem undirection to sink, the cycles of application may be single-period or multi-period.DMAC is a low-lantency and energy-efficiency MAC protocol base on a data collectiontree, which effectively improves network energy consumption and transmission delay.Either WSN of single-period applicaion or multi-periods application, data collisionprobability increases significantly, while the sensor nodes send data simultaneously,based on its competition mechanism. The data conflict causes growth of energy wasteand transmission delay. Based on the data prediction mechanism of DMAC, nodes willturn to receive state after sleep3slots when they received data in receive state. Thenodes will turn to receive state again after3slots until they did not received data inreceive slot. This causes energy waste because of the idle linsten, which is caused bydata prediction mechanism of DMAC.In WSN of single period, we proposed STSA-MAC that is specific to the aboveproblems. The STSA-MAC protocol allocate send slot and receive slot of each node bysink, which can effectively reduce energy waste caused by idle linsten. We also proposeBSTSA-MAC wich aims at the scene of single periodical data upload with burst data.After NS2simulation, the performace of STSA-MAC and BSTSA-MAC protocol isbetter than the DMAC agreement.In WSN of multiple periods, based on the STSA-MAC protocol, which send slotand receive slot of each node is allocated by sink, we propose MSTSA-MAC. In MSTSA-MAC the solt of each node is decided by sink and the ACK information, whichis replied by father nodes. By reasonable arranging time slot of each node, it reachesavoiding of enery waste and tranmision delay, which is caused by data collision. It alsoavoids energy waste caused by idle listen. We also proposed BMSTSA-MAC, whichrespects to the scene of busty data. Under NS simulation, a higher performace isachieved compared with DMAC.