Advanced Materials Research Vols. 765-767

Abstract: The hybrid signals are the combined signals with multi-modulation mode. With multi-modulation, the disadvantages of single-modulation (such as FSK, PSK and PPM) can be eliminated. By taking the advantages of different modulations, the performance of range resolving, Doppler resolving and low probability of intercept (LPI) of the signal can be improved. FSK/PSK radar signal is the signal with both FSK and PSK modulation at one time. It is with large Bandwidth Time product (BT), thumbtack-like ambiguity function and well ability of Anti-EMI. The FSK/PSK signals of which the frequency-hopping and bi-phase sequences were randomly chosen often had high side lobe level. With the simulation and analysis using MATLAB, the method of FSK modulation is made analysis. As a result, the automatic modulation recognition is one of the necessary functions.

Abstract: This paper theoretically analyzes the atmospheric influences on Ultraviolet (UV) communication, in which the main considerations include atmospheric absorption and atmospheric scattering. Through the establishment of mathematical model, this paper describes the atmospheric transmittance with different wavelengths. Finally, the atmospheric transmittance is simulated under different visibilities, rainfall and paths. The results show that the atmospheric transmittance will be different with different wavelengths, visibilities and rainfall. The atmospheric transmittance in horizontal path is larger than that in the vertical path. This research provides a theoretical guidance on the using of UV communication for the information transmission in power grid.

Abstract: The smart grid is emerging as a convergence of information and communication technology with power system engineering, and many network technologies can be used for communications in the generation, distribution and consumption part of the smart grid. However, finding the most appropriate technology that can satisfy their future communication needs is still a challeging issue. In this paper, we survey EPON-based communication systems for Neighborhood area networks (NAN) of smart grid, and both field based application and customer based application are discussed.

Abstract: We study the overload control problem of application server in the next generation electric communication network in this paper. We introduce an energy efficiency overload control algorithm based on simulated annealing. Firstly, by considering the overload control and energy efficiency, we construct the relations function between the input rate control and energy efficiency using rate allocation. Then, we construct the optimal overload control model of energy efficiency by regarding this relation function as objective function and overload control as constraint conditions. Thirdly, we use simulated annealing algorithm to solve this model, and then obtain the optimal solution during the iterative process. The simulation results show that our algorithm is feasible and effective.

Abstract: In order to design given minimum gap hopping sequences based on dual sub-bands for technology requirement, with Matlab simulation software analysis and optimize system, performance and design idea of hopping sequences of given minimum gap is expounded. The design method based on hardware of given minimum gap hopping sequences based on dual sub-bands is given. System software uses Quartus II8.0 platform and VHDL language. The language has fine characteristics of transplantation, long lifecycle, powerful description and support large scale design and logic unit recycled. The design has parameter adjustment repeating program function and reference application value in design of hopping-frequency communication hardware.

Abstract: For the complex recognition of signals in the aeronautical communication, the recognition of the star-type MQAM signals is studied under the aeronautical channel. The different scenarios of the aeronautical channel are analyzed and the reasonable channel model is established. The high order cumulant recognition algorithm which applies to the aeronautical channel is proposed, the invariant classification characteristics of modulation signals are constructed by this algorithm, and this algorithm is improved by using the receive diversity technique. Simulation results show that this algorithm significantly improves the correct recognition rate of the received signals has the good anti-fading and anti-noise performance and meets the requirements of the modulation recognition of MQAM signals under the aeronautical channel.

Abstract: Now more and more based on gesture interaction system applications, but there are simple gestures to operate the mouse interaction, no text input to the system function. In this paper, the blind letters gestures as input gestures ,using kinect to get the depth image, gestures split, use SIFT feature extraction, then get manual alphabet as Pinyin input method to provide an Chinese character input to the system.

Abstract: In this work, we have studied the optimal spectrum sensing interval, which is the time between two consecutive spectrum sensing activities, such that the delay of the cognitive transmission is minimized. The throughput maximization of the cognitive radio is always a common goal of the researchers, which is keenly related to the delay of the cognitive transmission. Whereas the delay is mostly decided by the spectrum sensing interval for a given primary user (PU) channel. Therefore, we have studied the setting of the spectrum sensing interval to minimize the transmission delay of the secondary user (SU). Especially, the retransmission is considered, which deteriorates the delay of the cognitive transmission; however, neglected by the most studies. Finally, we provide both the optimal setting of the spectrum sensing interval and the numerical values.

Abstract: The cross-correlation performance between epilepsy electroencephalogram (EEG) signals reflects the status of epilepsy patients which has importance for analyzing long-range correlation of non-stationary signals. For the first time, detrended cross-correlation analysis (DCCA) was applied to analyze different physiological and pathological states of epilepsy EEG signals. It were compared the difference of DCCA values between epilepsy patients EEG signals and normal subjects EEG signals. It was found that the DCCA values of epilepsy patients EEG signals increased compared the normal subjects EEG signals which can be helpful for medical diagnosis and treatment.

Abstract: Most studies considering spectral features of HRV during sleep divided total frequency band into low frequency (LF, 0.04~0.15Hz) and high frequency (HF, 0.15~0.4 Hz) roughly, and were limited to a few measures like the power in LF and HF, or the ratio of them. To make full use of HRV, more comprehensive spectral features were evaluated in this paper. LF was further divided into true LF (0.04~0.1Hz) and medium frequency (0.1~0.15Hz). Spectrum power, mean frequency and spectral entropy of different spectral bands, fractal dimension and peak in HF (20 measures in total) were calculated for wake, REM, light sleep and deep sleep. The significance between sleep stages of each feature was evaluated. The random forest method was adopted for sleep staging and features importance rank. The results suggested that almost all the new proposed features showed significant differences during different sleep stages. They can improve sleep stages classification performance notably. Our study provided new features for sleep stages classification based on ECG.