CHANNEL SWITCHING APPARATUS AND METHOD OF A BASE STATION AND CHANNEL SWITCHING APPARATUS AND METHOD OF A TERMINAL BASED ON THE COGNITIVE RADIO SYSTEM

    公开(公告)号:CA2708838A1

    公开(公告)日:2009-06-25

    申请号:CA2708838

    申请日:2008-12-05

    Abstract: In a cognitive radio system, when communication in an operational channel is determined to be discontinued due to that an incumbent user (IU) entering the operational channel that is currently being used or due to that an excessive interference occurring in the operational channel, the operational channel is switched to a pre-arranged channel. However, since some parameters are different between the operational channel and the pre-arranged channel, an initialization procedure has to be performed to allow the cognitive radio system to be adapted to those some parameters. Since an initialization technique aiming for this situation is not developed yet, a conventional cognitive radio system uses a general initialization technique used to initially operate a system. However, the general initialization technique has to allow the system to be adapted to many parameters so that it takes a relatively long initialization time. A channel switching apparatus and method thereof of a base station, which allocates a slot for data exchange with each of a plurality of terminals in a frequency channel that is not used by the IU and thus performs communication, include transmitting a channel switching message for requesting to switch to a backup channel when a signal of the IU is sensed in the frequency channel; transmitting a beacon frame via the backup channel, wherein the beacon frame comprises allocation information about slots which are in the frequency channel and which are respectively allocated to each of the plurality of terminals; and allocating the slot for data exchange with each of the plurality of terminals to the backup channel according to the allocation information, and communicating with each of the plurality of terminals. By doing so, frequency resources between each of networks can be efficiently used, and convenience and efficiency with respect to network operation can be maximized.

    METHOD AND APPARATUS FOR CONTROLLING TRANSMIT POWER OF COGNITIVE RADIO DEVICE

    公开(公告)号:CA2760269A1

    公开(公告)日:2010-11-04

    申请号:CA2760269

    申请日:2010-04-29

    Abstract: The present invention relates to a transmission power control method and device. The transmission power control method for a cognitive radio device according to one embodiment of the present invention includes obtaining CR environmental information about a registered user or an unregistered user occupying an adjacent channel or an adjacent cell of a cognitive radio device, determining a transmission power value of the cognitive radio device using the CR environmental information, and generating transmission power control information including a transmission power value. According to the present invention, the reliable communication of the cognitive radio device can be guaranteed and at the same time interference for a registered user can be minimized.

    METHOD AND APPARATUS OF GENERATING SIGNALS FOR INITIAL RANGING IN OFDMA SYSTEM

    公开(公告)号:CA2684306A1

    公开(公告)日:2008-10-30

    申请号:CA2684306

    申请日:2008-04-21

    Abstract: Provided is a method and apparatus of generating signals for initial rang ing in an Orthogonal Frequency Division Multiple Access (OFDMA) system. The method, includes: generating a plurality of ranging symbols by cyclic-shifti ng sample data of a ranging symbol in one OFDMA symbol period as much as a v alue obtained by multiplying a cyclic prefix size by a symbol index; generat ing a ranging signal by copying a rear part corresponding to the cyclic pref ix size in the sample data with respect to each of the ranging symbols and i nserting the copied rear part in front of the sample data as a cyclic prefix .

    VERFAHREN UND VORRICHTUNG FÜR KANALCODIERUNG IN EINEMDRAHTLOS-KOMMUNIKATIONSSYSTEM

    公开(公告)号:DE112010002802T5

    公开(公告)日:2012-08-23

    申请号:DE112010002802

    申请日:2010-06-30

    Abstract: Bereitgestellt wird ein Verfahren und eine Vorrichtung für Kanalcodierung in einem Drahtlos-Kommunikationssystem. In dem Kanalcodierungsverfahren wird die Größe von ersten Auffüllbits derart ermittelt, dass die Zahl von Bits von codierten Daten, welche durch Kanalcodierung und Punktierung von zu übertragenden Informationsdaten erzeugt werden, eine ganze Zahl wird, und die ersten Auffüllbits werden in die Informationsdaten eingefügt. Die Größe von zweiten Auffüllbits wird derart ermittelt, dass die Gesamtzahl von Bits der codierten Daten ein Vielfaches der Übertragungseinheit wird, wenn durch Modulation der codierten Daten erzeugte Symbole auf einer Übertragungseinheit-Basis Übertragungsressourcen zugeordnet werden, und die zweiten Auffüllbits werden in die codierten Daten eingefügt.

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