Patent application number | Description | Published |
20110045862 | APPARATUS AND METHOD FOR COMMUNICATION IN COGNITIVE RADIO NETWORK - A CR apparatus for performing communication in a CR network includes: a communication unit configured to measure a channel estimation signal, transmit measured channel state information to a master device, and, when a QP of a reference channel arrives, make a communication channel transition to a candidate channel and perform communication; and a channel information management unit configured to receive and manage the channel state information measured by the communication unit and channel information comprising a candidate channel, into which a channel transition is to be made during a QP of the reference channel, received from the master device and control channel transition of the communication unit based on the channel information. | 02-24-2011 |
20110103320 | CONTENTION-BASED DATA COMMUNICATION APPARATUS AND METHOD - Provided is a contention-based data communication apparatus and method that may notify that a radio resource is to be used using a search signal prior to transmitting a communication frame, and may transmit data based on a priority when a search signal received from another communication apparatus is detected. | 05-05-2011 |
20110149889 | METHOD AND DEVICE FOR COMMUNICATION BETWEEN DEVICES WITH DIFFERENT TRANSMISSION COVERAGE - Provided is a large range management device (LRMD) of managing a communication between a plurality of small range devices (SRDs) and a plurality of large range devices (LRDs), the SRDs and the LRDs being located in a single cell and having different transmission coverage, the LRMD including an access slot allocation unit to allocate an SRD access slot to a radio resource for a downlink, to enable a first SRD to request an association from a network, a selection unit to select a communication relay device for relaying relay data of the first SRD, a relay slot allocation unit to allocate at least one SRD relay slot to a radio resource for an uplink, to enable the communication relay device to relay the relay data to a second SRD or another LRD, and a receiving unit to receive the relay data based on the at least one SRD relay slot | 06-23-2011 |
20120100883 | TRANSMISSION POWER CONTROL METHOD AND DEVICE FOR COGNITIVE RADIO DEVICE - A method and an apparatus for controlling transmit power of a CR device are provided. The method includes acquiring CR environment information regarding a licensed user or an unlicensed user occupying an adjacent channel or an adjacent cell of the CR device; determining a transmit power value of the CR device using the CR environment information; and generating transmit power control information including the transmit power value. The method and apparatus guarantee reliable communication of the CR device and minimize interference with the licensed user. | 04-26-2012 |
20120288021 | SECONDARY TRANSMITTER INCLUDED IN COGNITIVE RADIO COMMUNICATION SYSTEM AND COMMUNICATION METHOD OF THE SECONDARY TRANSMITTER - Provided is a communication method of a secondary transmitter included in a multiple-antenna based multiple input multiple output (MIMO) cognitive radio communication system, the method including: estimating an interference channel between the secondary transmitter and a primary user in each of at least one first spectrum band that is being used in a primary system; calculating an orthogonal projection matrix to cancel interference with respect to the primary user from the interference channel; calculating an effective channel between the secondary transmitter and a secondary receiver based on the to orthogonal projection matrix; and selecting an index of an optimal spectrum band from the at least one first spectrum band based on the orthogonal projection matrix and the effective channel. | 11-15-2012 |
20120289266 | COGNITIVE RADIO BASE STATION AND COMMUNICATION METHOD THEREOF IN MULTI-USER MULTIPLE-INPUT MULTIPLE OUTPUT COGNITIVE RADIO NETWORK SYSTEM - A communication method for a cognitive radio (CR) base station in a multi-user multiple-input multiple-output (MIMO) CR communication system including the CR base station and CR terminals, may include calculating, from an interference channel, an orthogonal projection matrix to be used for removing interference on a primary user through use of a zero forcing (ZF) processing scheme, and obtaining a beamforming weight vector for each of the CR terminals, through use of the orthogonal projection matrix. | 11-15-2012 |
20130163572 | COMMUNICATION METHOD USING A PREAMBLE TO SHARE CHARACTERISTIC INFORMATION, METHOD FOR GENERATING THE PREAMBLE, AND COMMUNICATION SYSTEM TO WHICH THE METHODS ARE APPLIED - A communication method of a transmitter using a preamble in a wireless communication system, includes determining at least two subcarriers from among a plurality of subcarriers, for the preamble; mapping a subcarrier sequence and a subcarrier phase value of the preamble to the at least two subcarriers; and transmitting the preamble using the at least two subcarriers. The preamble may include a real component having a first repeated pattern in a preset time interval, and an imaginary component having a second repeated pattern in the preset time interval, and a relationship between the first repeated pattern and the second repeated pattern may indicate characteristic information of the wireless communication system. | 06-27-2013 |
20130163575 | CONTENTION BASED CHANNEL OCCUPYING METHOD IN WIRELESS NETWORK USING A PLURALITY OF CHANNELS - Disclosed is a contention based channel occupying method in a wireless network using a plurality of channels, including: acquiring, by terminals that are incapable of transmitting a data frame through primary contention, occupation channel information from a terminal that transmits the data frame through the primary contention; verifying, by the terminals, an occupiable channel based on the occupation channel information; and performing, by the terminals, secondary contention in the occupiable channel. | 06-27-2013 |
20130315342 | METHOD AND DEVICE FOR TRANSMITTING A PREAMBLE IN A WIRELESS COMMUNICATION SYSTEM - A wireless communication system provides a method and device for transmitting a preamble. A transmitter generates a first preamble sequence used for frequency offset estimation and generates a second preamble sequence according to the transmission mode. The transmitter transmits the first and second preamble sequences. With respect to the second preamble sequence, the phase thereof may be shifted into different phase offsets according to the transmission mode. | 11-28-2013 |
20130336175 | METHOD AND APPARATUS FOR DUPLEX IN COGNITIVE RADIO COMMUNICATION SYSTEM - Provided is a method for duplex in a cognitive radio communication system, including: collecting radio environment information including information of usable radio resources; determining a duplex scheme for each radio resource based on the radio environment information; and allocating at least one of the radio resources to information to be transmitted and received, depending on characteristics of the information. | 12-19-2013 |
20140162715 | CHANNEL INFORMATION PROVIDING METHOD, CHANNEL INFORMATION PROVIDING DATABASE SERVER, AND CHANNEL INFORMATION PROVIDING SYSTEM - The present invention provides a channel information providing method, a channel information providing database server, and a channel information providing system which receive channel quality information from a cognitive radio terminal which receives channel information based on position information and efficiently use channels using the received information. A channel information providing method which uses a database server to provide channel information to a cognitive radio terminal based on position information includes providing channel information to at least one cognitive radio terminal; receiving collected information regarding a quality of the channel from the at least one cognitive radio terminal; and determining to update the channel information provided in the providing using the information received in the receiving. | 06-12-2014 |
20140200017 | COGNITIVE RADIO APPARATUS AND COMMUNICATION METHOD THEREOF - To perform communication in a cognitive radio network, a cognitive radio apparatus according to an exemplary embodiment includes: an estimation module configured to generate a channel estimation signal to be transmitted to a predetermined reception apparatus positioned in a predetermined channel in the case of selecting the predetermined channel from among multiple channels; a communication module configured to transmit the channel estimation signal to the predetermined reception apparatus, and to receive a channel response signal from the predetermined reception apparatus; and a control module configured to control the communication module so that at least one of a communication signal set with respect to the predetermined channel and a variable communication signal obtained by varying the communication signal is transmitted to the predetermined reception apparatus, when it is determined that the predetermined channel is positioned in a deep fading section based on the channel response signal. | 07-17-2014 |