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 TD-LTE-A system, dual layer beamforming is introduced to improve throughput of specific users with high SINRs. In order to solve the problem of resource allocation for multi-user dual layer beamforming, a low complexity joint user grouping and resource allocation algorithm is proposed in this letter. We first calculate priorities of all active users according to channel quality and then the resource...
Coordinated multipoint (CoMP) is proposed recently as a promising technique to improve the performance of cellular networks and meet the increasing demand for digital service. However it faces several constraints to perform CoMP scheme in real systems. In this paper, we consider a downlink CoMP system and formulate the resource allocation problem of it in terms of resource block (RB) scheduling and...
In this work, we present a polarized-MIMO enabled cooperation framework between multiple secondary users (SUs) and a single primary user (PU). To achieve a two-phase cooperative communication paradigm, some state-of-the-art polarization signal processing techniques, e.g., polarization zero-forcing and oblique projection polarization filtering, are introduced to address the co-channel interference...
This paper investigates the effects of spectrum sensing errors on the performance of cognitive radio based dynamic spectrum access system (CR-DSA). We first analyze the DSA process with imperfect sensing information by a continuous-time Markov chain (CTMC) model, and then derive the performance metrics with respect to the sensing errors. To alleviate effect of errors in the spectrum sensing process...
This paper considers energy-constrained cognitive radios (CR) which can access a time-slotted licensed spectrum band in hybrid mode. At the beginning of each time slot, CR decides whether to be idle or to transmit. If transmission, CR has to determine which access mode to operate in. If the underlay mode is selected, CR shares spectrum with licensed systems by transmitting with a low power to ensure...
In cognitive radio (CR) networks, the secondary users are allowed to use the licensed frequency bands of the primary users (PUs) when these bands are vacant. However,once the PUs come back, they may collide with the transmitting secondary users. Therefore, the secondary users are generally required to sense the channel periodically to ensure that the primary users are absent during their data transmission...
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.