Space-Time Coding Technologies In Wireless Sensor Network

The wireless sensor network is a new generation of sensor network, large amounts of sensor nodes compose network with auto cooperative net protocol. WSN can realize the collecting information, data transmitting and managing, it can contribute a lot to both the military affair and daily life, and it is a new hotspot of the research work. WSN has a very broad application prospects, the development and application will make great contribution to the various fields of human life. Therefore, the relevant coding technology of this network has become a hot research field. Besides since the relative scarcity of wireless spectrum at the same time, multiple-input multiple-output (MIMO) systems nowadays have been demonstrated their good performance, the study shows that When the different receiving antennas and the transmitting antennas are isolated, MIMO systems can be used to improve the system performance. To achieve the capacity growth, several space-time signal processing techniques were proposed, such as a traditional VBLAST algorithm and etc. In this paper, Based on the conception of segmented detection, we propose an improved noise-predictive partial decision-feedback detector, it introduces the MMSE principle and divides the receive signals into two segments. Firstly , detects the signal with liner algorithms, secondly, bases on the noise predictive theory, it predicts the rest noise of the signals , and subtracts it, finally detects all the signals. Since only feeding back the decision once, the MMSE-PDF detector reduces complexity significantly compared to the conventional ODF detector. Meanwhile, The paper do some research work about the different constructions of WSN and virtual MIMO technologies. It combines different distributed space-time block coding techniques and the wireless sensor networks, through the simulation and comparison , it suggests that the performance of the network becomes better when the active nodes number becomes larger, as a result, the application of MIMO technology in WSN has good prospects for the future study.