| Patent application number | Description | Published |
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| 20090016293 | METHOD FOR SENSING SPECTRUM AND ARRANGING QUIET PERIOD IN COGNITIVE RADIO SYSTEM, CUSTOMER PREMISE EQUIPMENT, BASE STATION AND SUPERFRAME STRUCTURE USING THE SAME - Provided are methods of spectrum sensing and assigning quiet periods in a cognitive radio system in order to increase the reliability of detection regarding whether an incumbent user appears in his/her frequency channel, customer premises equipment (CPE), a base station, and the structure of a super frame for performing the methods. The spectrum sensing method includes communicating with a base station (BS) and performing spectrum sensing for frequency channels having quiet periods (QPs) during the QPs of the frequency channels used in the cognitive radio system, wherein the QPs of the frequency channels do not overlap each other | 01-15-2009 |
| 20090135713 | METHOD FOR USING FLEXIBLE BANDWIDTH IN OFDMA-BASED COGNITIVE RADIO SYSTEM, BASE STATION AND SUBSCRIBER STATION USING THE SAME - Provided are a method for using a flexible bandwidth in an orthogonal frequency division multiple access (OFDMA)-based cognitive radio system, and a base station (BS) and a subscriber station using the method. The method includes: allocating a channel band from among unused channel bands having a bandwidth that is a natural number times a bandwidth resolution to customer premises equipment (CPE), wherein the bandwidth resolution is a predetermined bandwidth smaller than a bandwidth of a broadcast channel band, and transmitting an OFDMA-based signal comprising band allocation information indicating information regarding the allocated channel band. | 05-28-2009 |
| 20090190537 | METHOD, APPARATUS FOR DYNAMIC RESOURCE ALLOCATION METHOD IN OFDMA-BASED COGNITIVE RADIO SYSTEM AND FORWARD LINK FRAME STRUCTURE THEREOF - Provided are a dynamic resource allocation method and apparatus in an Orthogonal Frequency Division Multiple Access (OFDMA)-based cognitive radio system and a downlink frame structure of the method and apparatus. The method includes a base station (BS) selecting one of an Adaptive Modulation and Coding (AMC) subchannel allocation scheme, in which a subchannel comprising at least one bin comprising a first plurality of continuous subcarriers in a frequency domain, is allocated, and a diversity subchannel allocation scheme, in which a subchannel comprising a second plurality of scattered subcarriers in the frequency domain is allocated, according to a level of frequency selectivity of an unused idle frequency band; and the BS allocating at least one subchannel to a terminal according to the selected subchannel allocation scheme. Accordingly, downlink throughput in the cognitive radio system can be increased. | 07-30-2009 |
| 20090219909 | METHOD FOR SWITCHING AND MANAGING FREQUENCY ACCESS IN COGNITIVE RADIO SYSTEM, BASE STATION AND SUBSCRIBER STATION USING THE SAME - Provided are a channel switching method for effectively performing channel switching in a cognitive radio system while protecting an incumbent user, a method of managing a frequency channel, and a base station and customer premises equipment (CPE) using the methods. In the channel switching method performed by the base station, a currently unavailable first frequency channel is detected from among at least one uplink/downlink frequency channel which is set as a communication channel with the CPE; a channel switching request message requesting switching from the first frequency channel to a second frequency channel is transmitted to the CPE; and the first frequency channel is switched to the second frequency channel when a channel switching report message reporting that channel switching is to be performed in response to the channel switching request message is received from the CPE. | 09-03-2009 |
| 20100202401 | METHOD AND APPARATUS OF HYBRID BURST MAPPING IN OFDMA SYSTEMS - Provided are a method of adaptively allocating appropriate hybrid bursts according to terminal attributes including terminal position, channel state, and service type in an orthogonal frequency-division multi-access (OFDMA) system, and an upstream-MAP information element (US-MAP IE) structure supporting the method. The method includes dividing an upstream subframe into a plurality of zones depending on the number of OFDMA symbols and allocating bursts of a zone to a terminal according to the terminal attributes. Bursts are formed by allocating slots along a time axis in the upstream subframe, and are formed by allocating slots along a frequency axis in a downstream subframe. | 08-12-2010 |
| 20100260106 | NETWORK COMMUNICATION METHOD AND NETWORK DEVICE USING PREAMBLE - Provided are a network communication method and a network device using a preamble. According to the network communication method and the network device, network coexistence is easily achieved by using network identification transmitted in the preamble, and an unknown terminal, which has a low reception signal to noise ratio (SNR) and has not yet been connected to an existing network, is easily connected to the existing network. | 10-14-2010 |
| 20100265871 | BEACON RE-BROADCASTING APPARATUS, BEACON RE-BROADCASTING METHOD, AND INITIAL ACCESS REQUEST METHOD IN WIRELESS NETWORK - Provided are a beacon re-broadcasting apparatus, a beacon re-broadcasting method, and an initial access request method in a wireless network. In the re-broadcasting apparatus and method, a beacon frame including beacon information for communications in the wireless network and information on an echo beacon slot allocated for beacon re-broadcasting among time slots of a superframe is received from a management device for managing the wireless network in which a plurality of terminals communicated with each other through the superframe including time-divided time slots, and the beacon information is re-broadcasted during the echo beacon slot. Accordingly, the beacon information can be received in various environments, and the beacon information can be received to an adjacent network in addition to the corresponding network. Therefore, frequency resources can be shared and effectively used between networks, and convenience and efficiency in network operation can be maximized. | 10-21-2010 |
| 20100272039 | METHOD OF MANAGING MULTIPLE CHANNELS IN SINGLE NETWORK AND NETWORK MANAGEMENT DEVICE - Provided are a method of managing multiple channels in a single network, and a network management device, also referred to as a network management system. According to the method and the network management device, all devices in one network that operate by using multiple channels share core information, and are effectively controlled. | 10-28-2010 |
| 20100284355 | HANDSHAKING METHOD, AND TRANSMISSION POWER DETERMINING METHOD AND APPARATUS THEREOF FOR PARALLEL TRANSMISSION OF MULTIPLE STREAMS IN SINGLE RADIO CHANNEL - Provided are a transmission power determining method and an apparatus thereof for parallel transmission of a plurality of streams. In a wireless communication system, the transmission power determining method and apparatus determine a transmission power suitable for allowing the plurality of streams to be simultaneously and reliably transmitted in a mutually permissible interference range, and use a Hidden Handshaking (HHS) procedure to determine the transmission power. By doing so, it is possible to perform reliable channel allocation and to reliably transmit the plurality of streams. | 11-11-2010 |
| 20100290416 | CHANNEL SWITCHING APPARATUS AND METHOD OF A BASE STATION AND CHANNEL SWITCHING APPARATUS AND METHOD OF A TERMINAL BASED ON THE COGNITIVE RADIO SYSTEM - 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. | 11-18-2010 |
