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.
Spectrum sensing is one of the key technologies of cognitive radio. Based on noise characteristics estimation and support vector machine (SVM) technology, this paper proposed a frequency domain two-stage spectrum sensing method to improve sensing accuracy under low signal-to-noise ratio scenarios with low system complexity and high generalization ability. In the slow sensing stage, the frequency-domain...
For popular Open Source Software (OSS) projects there are always a large number of worldwide developers who have been glued to making code contributions, while most of these developers play the role of casual contributors due to their very limited code commits (for fixing defects and enhancing features, casually). The frequent turnover of such group of casual developers and the wide variations among...
This paper addresses an energy-efficiency (EE) maximized resource allocation (RA) problem for cooperative orthogonal frequency division modulation (OFDM) transmission, when the system's total power consumption (including the circuit power and transmission power) is limited below a peak value. The improved DF relaying protocol proposed in [1] is used with optimized subcarrier pairing. The EE is evaluated...
Region duplication is a simple and effective operation to create digital image forgeries, where a part of the image is copied and pasted on another part of the same image. Most existing region duplication detection methods are based on directly matching blocks of image pixels or transform coefficients, and are not effective when duplicated regions have affined transforms or blur degradations. In this...
This paper considers a multi-cell relay aided orthogonal frequency division multiple access (OFDMA) downlink system, in which all stations are coordinated by a central controller for resource allocation (RA). The decode-and-forward (DF) protocol with selection relaying (SR) is applied. The problem considered is the maximization of the weighted sum of per cell min-rate (WSMR) with a total power constraint...
To reduce the cost and complexity of receiver without losing much diversity gain, we propose an antenna selection scheme for MIMO systems employing non-constant envelope mapping. By detection of the received signal and a simplified process without any knowledge of channel statement information, this scheme can approach the ideal selection strategy. Single carrier system and STC-OFDM (space-time-code...
The high peak-to-average power ratio (PAR) in Orthogonal Frequency Division Multiplexing (OFDM) modulation systems can significantly reduce power efficiency and performance. This paper examines the problem of reducing the peak-to-average power ratio (PAPR) occurring in OFDM systems based on IEEE 802.11a. A low complexity PAPR reduction algorithm is proposed. A revised ACE-POCS method is put forward...
The prediction of protein 3D structure has become a hot research area in the post-genome era, through which people can understand a protein's function in health and disease, explore ways to control its actions and assist drug design. Many protein structure prediction approaches have been proposed in past decades. Among them, Rosetta is one of the best systems. However, the huge time complexity of...
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.