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In this paper, we propose a machine learning based spectrum sensing method using the sample covariance matrix of the received signal vector from multiple antennas. Before sensing, the cognitive radio (CR) will first apply the unsupervised learning algorithm (e.g., K-means Clustering) to discover primary user's (PU) transmission patterns. Then, the supervised learning algorithm (e.g., Support Vector...
In this paper, a novel spectrum sensing scheme, which is robust in the presence of impulsive noise, is proposed to meet the rigid requirements for sensing accuracy. An efficient least trimmed square algorithm incorporated with an adaptive signal trimming scheme is proposed to eliminate the set of signal samples contaminated by impulsive noise. Spectrum sensing based can be performed to the denoised...
Cooperative transmission is an efficient method for wireless sensor networks (WSN) to decrease the power consumption of sensor transmitter and counter the detrimental effect of signal fading inherent to wireless channels. During the course, a key issue is how the sensor relay should handle the balance of assisting other node's communications and accomplishing its own tasks and what kind of situation...
To reduce the idle access, an algorithm featured by low channel access delay and priority differentiation service was proposed for the access procedure of IEEE 802.11. A state-dependent two-level polling model was established to analyze the QoS performance of M2M under unsaturated condition and perfect channel in the IEEE 802.11. To improve the transmission effective of massive M2M service, machine...
In order to improve the characteristics for satellite data expression ability, it is proposed sparse coding with over complete bases, to induce the high dimensional feature vectors form down to up pattern, then to accurately express the original high-dimensional features with very few over complete basis vectors. From top-down semi supervised learning characteristics, to project high dimensional feature...
Human detection is a key problem in computer vision, with several applications that have the potential to positively impact quality of life. In recent years, the number of approaches to detect human in video sequences has grown steadily. This paper proposed a novel approach to improve the capability of human detection. After investigating the image texture analysis methods, we adopt the new good texture...
In this paper, two resource allocation schemes based on genetic algorithm (GA) in heterogeneous wireless networks are proposed. The first scheme is called traffic-based resource allocation scheme (TRAS) which allocates the resource mainly based on the bandwidth requirements of traffic and bandwidth availability. In the second scheme which is called utility-based resource allocation scheme (URAS),...
This paper presents a planar printed quasi-Yagi antenna. The proposed antenna consists of a microstrip line slotline transition structure, a driver dipole and two parasitic stripes. The driver dipole is connected to the slotline through coplanar stripline (CPS) which is designed by using a pair of exponential curves and a circular groove end, just the Vivaldi antenna structure, so as to achieve a...
Dual connectivity is a promising architecture for the future hyper-dense wireless cellular network to meet the rapidly increasing demand of wireless data transmission. In this architecture, the control plane (C-plane) and the user plane (U-plane) are split and a User Equipment (UE) simultaneously connects to two different cells: the Primary Cell (PCell) which is in charge of the C-plane, and the Secondary...
The tremendous performance of large-scale multiple input multiple output (LS-MIMO) systems can be achieved by applying linear beamforming schemes, such as maximum ratio transmission and zero forcing, in time-division duplex mode. However, it is prohibitive to acquire the instantaneous channel state information (CSI) at the transmitter in frequency-division duplex (FDD) systems. Thanks to the compact...
A simulation platform for Chinese next generation broadcast wireless (NGB-W) terrestrial broadcast systems is introduced. The performance of NGB-W terrestrial broadcast systems in the ultra high frequency TV band is evaluated by simulations under various conditions. It is shown that the performance of NGB-W terrestrial broadcast systems is much better than that of the second generation terrestrial...
We propose three relay selection schemes for a cooperative network with secrecy constraints, where a decode-and-forward (DF) relaying policy is employed. The first scheme selects the relay having the minimum instantaneous signal-to-noise ratio (SNR) to the eavesdropper, the second one is max-min approach and the third scheme is the optimal selection criteria that maximizes the achievable secrecy rate...
We propose a novel method to generate photonic quadrature-phase-shift-keying (QPSK) vector signal by using only one Mach-Zehnder modulator (MZM). Because of the ‘square-law’ by the photo-detector, the amplitudes and the phase of the driving radio-frequency (RF) signal changed after detection. So the amplitude and the phase of the driving radio-frequency (RF) signal should be pre-coded before used...
A novel stochastic process shift keying (SPSK) to achieve a secure communication system in the presence of heavy noise is presented. The Gaussian noise sequence from the output of autoregressive (AR) filter carries the binary information. At the receiver, a damped sinusoidal model of autocorrelation function is employed to identify the two different AR filters from the noisy observations to estimate...
In this paper, we proposed an anti-interference cooperation spectrum sharing protocol with secondary user selection. Specifically, one secondary user is selected to assist the primary system to achieve the target rate by acting as a decode-and-forward (DF) relay, which uses a fraction of time and bandwidth to forward the primary signal. As a reward, the selected secondary user can gain spectrum access...
The texture feature is an important information for hyperspectral image classification. In this study, we extend the traditional 2D GLGCM(gray-level gradient cooccurrence matrix) into 3D GGGTF(gray-gradient-gradient tensor field), which can extract gray and gradient texture features of hyper-spectral volume data simultaneously. A few statistical features are extended into third-order forms in order...
Based on the assumption that the user nodes and relay node are equipped with multiple antennas, we propose the minimum mean squared error (MMSE) pre-equalization scheme to address the interference elimination issue for two-way AF MIMO relay systems. Compared to the zero-forcing (ZF) equalization and MMSE equalization, it is proved that MMSE pre-equalization scheme has the lowest noise power in MIMO...
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