Patent application number | Description | Published |
20110129006 | METHOD AND APPARATUS FOR DETECTING RECEIVED SIGNAL IN WIRELESS COMMUNICATION SYSTEM - A method for detecting a received signal includes: dividing the entire band of the received signal into N frequency components where N is a natural number larger than one, and deciding a reference frequency component containing a reference frequency as a first priority sensing band among the N frequency components; deciding the sensing priorities of the other (N−1) frequency components in such a manner that the sensing priorities spread in both directions from the first priority sensing band; calculating the magnitude of each of the N frequency components in accordance with the decided sensing priorities; comparing the calculated magnitude of the frequency component with a predetermined threshold value; and when the calculated magnitude of the frequency component is larger than the threshold value, determining that the received signal exists. | 06-02-2011 |
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 |
20140126617 | SIGNAL COMPRESSION APPARATUS AND METHOD FOR DYNAMIC COMPRESSIVE SENSING USING SPARSITY INFORMATION OF INPUT SIGNAL - Disclosed are a signal compression apparatus and method for dynamic compressive sensing, including: a signal input unit configured to simultaneously output an input signal, and generate and output a linear measurement reference signal based on the input signal; a linear transform unit configured to receive the linear measurement reference signal and variably generate a linear measurement matrix value according to the linear measurement reference signal; a signal compressor configured to output a compressed signal for the input signal based on the generated linear measurement matrix value; and a signal processor configured to reconstruct the compressed signal and perform spectrum sensing of the input signal. Accordingly, it is possible to increase signal compression efficiency of compressive sensing and improve signal reconstruction performance by using sparsity information of the input signal, and also by performing signal compression by using a compression matrix suitable for the sparsity information of the input signal. | 05-08-2014 |
20140169350 | APPARATUS AND METHOD FOR DETERMINING IDENTITY OF WIRELESS LAN SYSTEM - Disclosed are an apparatus and a method for determining an identity of a WLAN system occupying a channel, using information within a signal field or time synchronization between target channels. For this, the present invention includes a preamble detecting unit configured to detect a preamble in each channel; a channel information obtaining unit configured to obtain reference time information when the preamble is detected in each channel, or to obtain signal field information in each channel using the detected preamble; and an identity determining unit configured to determine an identity of a WLAN system occupying each channel by comparing the reference time information obtained in each channel, or by comparing the signal field information obtained in each channel. | 06-19-2014 |
20140177546 | APPARATUS AND METHOD FOR AVOIDING INTERFERENCE BETWEEN ACCESS POINTS - The present invention relates to an apparatus and a method for avoiding signal interference between access points (APs) in a non-license band, and more particularly, an interference avoidance apparatus and method between access points (APs) that avoid interference based on whether an overlapping basic service set (OBSS) is present, whether an overlapping operation channel between adjacent APs is used, whether it is possible to select a non-overlapping operation channel between adjacent APs, and the like. | 06-26-2014 |
20140198836 | METHOD AND APPARATUS FOR WIDEBAND SPECTRUM SENSING USING COMPRESSIVE SENSING - Disclosed is a method for wideband spectrum sensing using compressive sensing, the method including: acquiring a sampling signal by applying a modulated wideband converter (MWC) to a received signal; and acquiring a restoration signal corresponding to the received signal by using a compressive sensing restoration algorithm from the sampling signal, and a mixing signal multiplied by the received signal at the time of applying the MWC, as a signal transformed from a first mixing signal having a periodic waveform, includes a second mixing signal to remove a partial frequency area from the received signal through the application of the MWC. | 07-17-2014 |