Cognitive Radio (CR) is considered as an effective technology for alleviating the spectrum shortage problem by enabling secondary users to utilize vacant spectrum allocated to a primary user (PU). IEEE 802.22 which is...
详细信息
Cognitive Radio (CR) is considered as an effective technology for alleviating the spectrum shortage problem by enabling secondary users to utilize vacant spectrum allocated to a primary user (PU). IEEE 802.22 which is the first standard based on CR is developed to increase the efficiency of TV bands. However the physical layer security of IEEE 802.22 has been studied rarely. In this paper, we propose a scheme to sense the specific primary user for dealing with Primary User Emulation (PUE) Attack which is a possible threat to wireless security. According to ATSC digital TV which is one of the important PUs, we estimate the accuracies of pilot and symbol rate as RF fingerprint (RFF), and Support Vector Data Description (SVDD) is introduced to sense the fine differences of RFF to distinguish PUE attacker from PU. The simulation results show that the proposed scheme is feasible to verify the PUE attacker at a relative high SNR level.
Wideband spectrum sensing is a fundamental problem in cognitive radio networks. In this paper, a wideband spectrum sensing procedure which consists of four steps, i.e., coarse support recovery, fine binary detection, ...
详细信息
Wideband spectrum sensing is a fundamental problem in cognitive radio networks. In this paper, a wideband spectrum sensing procedure which consists of four steps, i.e., coarse support recovery, fine binary detection, band edges detection and clustering, for modulated wideband converter (MWC) based cognitive radio system at sub-Nyquist rate is proposed. Simulations show that with a sub-Nyquist sampling rate, the proposed spectrum sensing procedure can locate spectrum holes correctly.
Spectrum sensing is one of the fundamental problems for cognitive radio. In cognitive radio networks, cognitive radios can cooperatively sense the spectrum to detect the presence of primary users with higher sensitivi...
详细信息
Spectrum sensing is one of the fundamental problems for cognitive radio. In cognitive radio networks, cognitive radios can cooperatively sense the spectrum to detect the presence of primary users with higher sensitivity. This paper proposes distributed consensus algorithms for decision fusion based cooperative spectrum sensing. Both theoretical analysis and simulations are performed to show the convergence property of the algorithms. Results show that the proposed algorithms can realize central OR, AND, and M-out-of-n decision fusion rules by locally exchanging information among each radio and its adjacent neighbors in a distributed way.
Using the Yb3+ and Tm3+ doped SiO2 fiber rods as the samples and ultrafast 800 nm femtosecond (fs) laser sources, the multiphoton absorption characteristics and damage threshold are experimental investigated based on ...
详细信息
Passive localization using TDOA and FDOA measurements usually does not have direct solution and requires numerical methods to determine the emitter's geolocation. We examine a satellite passive localization method...
详细信息
Passive localization using TDOA and FDOA measurements usually does not have direct solution and requires numerical methods to determine the emitter's geolocation. We examine a satellite passive localization method based on particle swarm optimization(PSO), which provides an evolutionary computation method to solve the nonlinear optimal problem. However, PSO can not be straightforwardly applied to satellite passive localization because it is a constrained nonlinear optimal problem when using the constraint condition of the earth surface. We suggest "flying" the particle swarm directly using the earth surface constraint. Computer simulation results show the effectiveness of the new localization method.
In this paper, a SystemC-based hardware/software co-design methodology for embedded image processing system is presented. With the development of the IC process, traditional design methodologies cannot meet the requir...
详细信息
In this paper, temperature fuzzy controller was designed in the inverter cold and hot air-condition. The control system for inverter air conditioner was divided indoor machine and the outdoor machine. Frequency contro...
详细信息
In this paper a compact and wideband planar inverted-F antenna (PIFA) with metamaterial loaded on the ground plane is proposed. The metamaterial units, composed of an array of Jerusalem crosses PEC structure, improve ...
详细信息
In this paper a compact and wideband planar inverted-F antenna (PIFA) with metamaterial loaded on the ground plane is proposed. The metamaterial units, composed of an array of Jerusalem crosses PEC structure, improve the performance of the antenna and cause a special characteristic of backward radiation. Simulation results show that this novel antenna has a bandwidth of 49.4%, which is from 2.56 GHz to 4.24 GHz. Compared to a conventional PIFA simulated in this paper, the proposed antenna has a reduction of 91% in dimension. And the antenna has a gain over 3 dB within the whole bandwidth.
We present a fast collision detection method for deformable surfaces with parallel spatial hashing on GPU architecture. The efficient update and access of the uniform grid are exploited to accelerate the performance i...
详细信息
In the grid environment, the peer's behavior is uncertainty and dynamic which make the traditional Role-Based Access control Model(RBAC) cannot effectively identify various malicious behaviors of peer. We introduc...
详细信息
暂无评论