Transmission Schemes Of Wireless Sensor Network Based On Cooperative Diversity Technology

In wireless sensor network, cooperative diversity is a very important technology, whichenables users to share their antennas by using of the redundant node properties to improve spacetransmission diversity, also provide resistance to increase the output and channel fading effects. Buthow to transmit cooperatively during nodes in the wireless sensor network especially the receivingterminal nodes and how to decode for a higher efficient data transmission are still some furtherconsiderable questions.The MIMO+OFDM modulation technology was designed on the basis of multiple input andmultiple output（MIMO）technology and orthogonal frequency division multiplexing（OFDM）technology, which increases the channel capacity,uses the spectrum resources more effectively, alsothe receiver could use the enhanced signal-to-noise combing regardless of the channel quality toachieve better performances.An innovative superposition modulation strategy was introduced based on traditionaltransmission schemes, also a new symbol mapping method was designed based on the nodes’ linkstates and power allocation by using of this strategy, then discusses the receiving terminal node’sdecode problems about the signal-to-noise and bit error probability. This optimize arithmetic doesnot only solve one half of slot in use of the traditional cooperative mode by comparing with theno-cooperative mode and the decode-forward cooperative mode, but also decrease the bit errorprobability on performance. In addition, this new method could improve three dB signal-to-noise atmost than the traditional transmission mode in this paper. The simulation result shows that well linkstate with suitable power allocation does not only transmit their and partners’ data at the same time,but also balance system performances.Coordinated multiple points(CoMP) transmission technology is a typical application ofcooperative diversity technique, and the traditional MIMO system compares the root with theCoMP system in the paper, then researches the modularization BD algorithm and BD+SVDalgorithm on the basis of MIMO system. The simulation result shows that the CoMP system whichuses this algorithm can reach good performances on the anti-interference side of residential area andeven the edge of the residential area.