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In order to improve the prediction accuracy of the photovoltaic power prediction model, this paper presents a novel forecasting model, which is the combination between Principal Component Analysis (PCA) and Support Vector Machine (SVM) intelligent algorithm. PCA statistical method used to extract less principal components instead of the original meteorological factor. Then that is as the input of...
Cognitive radio (CR) is viewed as a novel approach for improving utilization of the precious radio spectrum. Spectrum sensing is one of the most important technologies in cognitive radio. A general presentation of OFDM technology and cooperative spectrum sensing are given in the first instance. In order to improve detection probability and reduce equipment complex and computation complex, to combine...
To settle the contradiction between scarce radio spectrum resource and the exigent requirement, effective methods of dynamic spectrum allocation are proposed in cognitive radio system. In this paper, game theory model and graph-coloring model are analyzed, which can improve spectrum efficiency and solve the deficiency of spectrum resource.
Ultra wideband (UWB) system operates by transmitting signals over a very wide band of spectrum, so there must be the problem of coexistence of UWB with other radio services besides the spread spectrum communication system. By designing the simulation models of UWB system and spread spectrum system which is used more broadly, the simulation experiments has been taken on the performance of spread spectrum...
The paper introduced the present insufficient situation of the frequency spectrum resource. Several effective techniques to raise the utilization efficiency of the spectrum and corresponding developments of their applications, such as the Cognitive Radios, the Ultra-Wide Band radio, the Water Filling Principle and the Detection & Avoidance Mechanism, are analyzed and compared, which are increasingly...
UWB communication system operates by transmitting signals over a very wide band in spectrum, so there must be a coexistence problem between UWB and the other radio services. In order to investigate the interference to the narrowband wireless services from the UWB devices, a novel three-dimensional projection interference model has been presented. This analysis model is fit for analyzing the interfered...
Ultra-narrow-band communications system can greatly improve the spectrum utilization efficiency, therefore it will ease the tension of spectrum. Unfortunately, arguments from academia still focus on its principle as well as the realization. UNB transmission system based on the FIR filter has been explored in this paper. The characteristic of UNB signal after the FIR filter was analyzed. Then information...
Abstract:The extremely low input power of GPS receivers make it easy to be interfered by the ultra-wideband (UWB) signals. The system model is proposed to discuss the properties of TH-UWB signals both in time and frequency domain. The interference generating from two distinct modulation schemes, pulse position modulation (PPM) and pulse amplitude modulation (PAM) of TH-UWB signals on GPS receivers...
With the development of the information technology, especially the wireless communications, the electromagnetic compatibility (EMC) problem between systems becomes more and more important. This paper uses Simulink to analyze the interference between the UAV system and the CDMA system, besides giving some discussion on the result
To research the systems' EMC problem between UAV (unmanned aerial vehicle) and UWB (ultra wide band) is very important and practical to multi-communication-system corporate working. This paper chooses a wireless channel model to research the EMI problem between UAV and UWB systems, which based on Matlab/Simulink. And it gives the simulation experimental analytical results
A highly sensitive and selective method has been developed for spectrophotometric determination of boron in plants, the method based on the color reaction of new reagent 1-(2,3,4-trihydroxybenzylideneamino)-8-hydroxynaphthalene-3,6-disulfonic acid (THBA) with boron (III). In an ammonium acetate solution of pH 8.0, boron(III) reacts with THBA to form a 1:2 yellow complex which has a maximum absorption...
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