The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In the cognitive radio networks (CRNs), efficient spectrum sensing is a key enabling techniques for the effective spectrum exploration. However, Majority of the existing works on spectrum sensing is conducted the spectrum sensing serially in cognitive radio networks, which may bring about the sensing delay problem. In this paper, in order to make full use of the available channel resources and improve...
Carrier synchronization is one of the key technologies of digital wireless communication. As a kind of four phase shift keying modulation method, QPSK has strong anti-interference ability of the suppressed carrier, which is widely used in digital wireless communications. On this basis, this article describes a Costas-loop coherent carrier extraction algorithm based on Arctangent phase detection. It...
For ensuring the security of the information transmission, safe encryption algorithms are needed to encrypt information in wireless communication networks. Currently, one relative common encryption algorithm is AES encryption algorithm. However, AES encryption algorithm is public, which brings many problems to its security. To solving the safe problem of AES encryption algorithm, one improved AES...
We consider a class of flexible joint manipulator system which is nonlinear and contains uncertainty. The inertial matrix can be used to construct Lyapunov function, even though some of the joints are prismatic. We construct subsystems via backstepping method and suggest a state transformation under which implanted control is used. From this state transformation, a robust controller, which is only...
A generation tripping control method based on trajectory sensitivity analysis and pattern search is proposed in this paper. Considering the nonlinear dynamic model of multi-machine power system, the trajectory sensitivity of instable rotor angle to all generators' output power is derived, which is used to screen candidate control targets for generator tripping, and then the optimal control strategy...
Aiming at a practical industrial network control system, this paper makes an analysis of types of data, their traffic and directions under different working conditions, and a selection of a link of maximum traffic as a typical one. The method of passive measurement is used to obtain the packets of different protocols passing through the link. The traffic of the corresponding protocols can be calculated...
In this paper, a multi-objective programming model for optimizing the topology of a practical industrial network control systems is established on the basis of the analysis of IP packets through each link, and then solved by Genetic Algorithm(GA). To ensure the effectiveness of GA, this paper proposes an individual coding scheme and its valid criterion, designs a set of specific genetic operators...
In order to reduce the cost and acquire the microsecond-level time synchronization, this paper has proposed the DF-NTP (Double filter NTP) and analyzed the algorithm of NTP (network time protocol) and the causes of synchronization error. The precision of time synchronization can be raised through filtrating the delay in the forward-backward path and reducing the influence of uncertain delay. The experimental...
In this paper, we consider the potential influences on energy efficiency when Device to Device (D2D) communication is introduced to small cell network with sleep scheme. To begin with, we obtain the optimal sleep strategy for small cells, then we define parameters sleep ratio (SR) and maximum sleeping cell (MSC) to describe system dormant situation. Furthermore, parameters λ and θ are defined to indicate...
With Device to Device (D2D) user equipment (DUE) sharing the same resources with traditional cellular user equipment (CUE), intra-cell interference is becoming a challenging issue nowadays in D2D underlaying network. However, due to the lack of convexity, globally optimal resource sharing scheme is generally unattainable. In this paper, we propose a genetic algorithm (GA) based user matching scheme...
Orthogonal experimental design (OED) is a well-known method in statistical experiment which aims to reduce the testing complexity. This paper tries applying OED to reduce the computational complexity in Multiple-input Multiple-output (MIMO) detection. Several times of sorted QR decomposition (SQRD) algorithm are applied firstly to get the diverse solutions. Then a subspace is constructed with the...
Device-to-Device (D2D) communication is expected to play a pivotal role in the next generation of LET/LTE-A network, which is able to improve the system throughput by reusing the cellular resource. However, the caused intra-cell interference is quite a challenging issue in D2D underlaying cellular network. In this paper, we propose a Genetic Algorithm (GA) based joint resource allocation and user...
Device to Device (D2D) underlaying cellular networks have drawn a lot of attention recently, in both Long Term Evolution (LTE) standardization as well as academic research, with its huge potential in increasing the system capacity. However, intra-cell interference is quite a challenging issue since D2D user equipment (DUE) may share the same resources with the traditional cellular user equipment (CUE)...
The world is witnessing a tremendous increase in data demands which is subject to the new emerging technologies, applications and services. 60 GHz communication network is one of such technology, claiming data rate in multi-gigabits. In this paper, we propose a scheduling algorithm for device-to-device 60 GHz network having directional antennas. The proposed algorithm utilizes the vertex coloring...
Multi-user Multiple Input Multiple Output (MU-MIMO) system is known to enhance the system capacity with low network delay. One of the biggest challenges with MU-MIMO is on the scheduling scheme which simultaneously selects multiple users to maximize the sum rate. Genetic Algorithm (GA) works perfectly as an optimal or suboptimal solution with quite low complexity to handle such problems. In this paper,...
To deal with the shrink of Picocell Downlink (DL) coverage areas, the concept of Cell Range Expansion (CRE) has been proposed, in which a positive value is added to the DL Reference Signal Received Power (RSRP) of picocell pilot signals.Although CRE will expand DL picocell footprint, it may also lead to severe DL inter-cell interference from macrocells since some picocell User Equipments (UEs) are...
A novel Multiple-input Multiple-output (MIMO) detection scheme based on orthogonal experimental design (OED) is proposed in this paper. By exploiting the initial solutions given by linear detection and non-linear detection algorithms, a searching subspace is constructed to obtain additional performance gain. Exhaustive searching method is optimal in the subspace, but with quite high complexity. Then...
In digital array radar (DAR) system, digital mono-pulse techniques with digital beam forming method are widely used recently. Firstly, this paper introduces the theory of amplitude-comparison of sum and difference lobes and phase and sum-difference digital mono-pulse. Secondly, noise and element amplitude and phase errors which affect the accuracy of angle measurement are analysed and simulated. Lastly,...
The application of modulated stepped frequency signal in digital array radar is discussed based on the High-Resolution image algorithms. The effects of phase error in every single-channel on high resolution range are analyzed, that is, the nonlinear increase in interpulse frequency will result in distorted main lobe and increased sidelobe, which affects the quality of radar imaging. Also, inconsistent...
Node localization with fewer resources and less computing time is an important and challenging issue in the field of wireless sensor network (WSN). There are a variety of localizing algorithms and testing methods to deal with that problem. Taking account of the error variable caused by practical interference and the difficulty to use standard mathematical function to describe the model, a method using...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.