In order to recognize the jamming pattern in anti-jamming, a novel fuzzy jamming recognition method based on statistic parameters of received signal’s power spectral density (PSD) is proposed. It exploits PSD’s shap...In order to recognize the jamming pattern in anti-jamming, a novel fuzzy jamming recognition method based on statistic parameters of received signal’s power spectral density (PSD) is proposed. It exploits PSD’s shape factor and skewness of received signal as classified characters of jamming pattern. After the mean center and variance of each jamming pattern are calculated by using some jamming samples, an exponential fuzzy membership function is used to calculate the membership value of the recognized sample. Finally, the jamming pattern of received signal is recognized by the maximum membership principle. The simulation results show that the proposed algorithm can recognize common eight jamming patterns accurately.展开更多
In this paper, we conduct research on the database technology under the basic operation of the IOT huge amounts of data. Spatial data service is the process of basic customer application system service request, direct...In this paper, we conduct research on the database technology under the basic operation of the IOT huge amounts of data. Spatial data service is the process of basic customer application system service request, directory service system according to the request is mapped into physical addresses, according to the data block physical disk server address block of data read from the disk in parallel and sent to the client the process of application system. In addition, spatial data distribution system should possess unloading, transfer, replication, and optimization of spatial data, and other functions, to achieve comprehensive management and maintenance of spatial data. Under this basis, we propose the enhanced database technology that optimizes the operation with better performance.展开更多
基金Sponsored by National Nature Science Foundation of China ( 61072078)China Postdoctoral Science Foundation Funded Project ( 20090461426)Jiangsu Planned Projects for Postdoctoral Research Funds ( 0902039C)
文摘In order to recognize the jamming pattern in anti-jamming, a novel fuzzy jamming recognition method based on statistic parameters of received signal’s power spectral density (PSD) is proposed. It exploits PSD’s shape factor and skewness of received signal as classified characters of jamming pattern. After the mean center and variance of each jamming pattern are calculated by using some jamming samples, an exponential fuzzy membership function is used to calculate the membership value of the recognized sample. Finally, the jamming pattern of received signal is recognized by the maximum membership principle. The simulation results show that the proposed algorithm can recognize common eight jamming patterns accurately.
文摘In this paper, we conduct research on the database technology under the basic operation of the IOT huge amounts of data. Spatial data service is the process of basic customer application system service request, directory service system according to the request is mapped into physical addresses, according to the data block physical disk server address block of data read from the disk in parallel and sent to the client the process of application system. In addition, spatial data distribution system should possess unloading, transfer, replication, and optimization of spatial data, and other functions, to achieve comprehensive management and maintenance of spatial data. Under this basis, we propose the enhanced database technology that optimizes the operation with better performance.