Abstract:
The purpose of the present invention is to provide a spectrum sensing signal detection device and a method thereof reducing errors generated from a discontinuous section in a step of detecting signals in spectrum sensing by easing the discontinuity of signals by adding a fader section at the front and back parts of the discontinuous signals. According to a desirable embodiment of the present invention, the spectrum sensing signal detection device for detecting signals, not continuous signals, for spectrum sensing comprises: an adding part for adding a fader section at the front and back parts of a capture section generated when data is captured for detecting the signals; and a detection part for detecting signals of the spectrum sensing using fast fourier transform (FFT) in the data where the fader section is added.
Abstract:
Disclosed are an apparatus and a method for synchronizing a reception signal in a cognitive radio system. According to the present invention, the apparatus for synchronizing the reception signal comprises a time synchronization unit for detecting a preamble signal and for estimating the start point of the preamble signal; a frequency synchronization unit for estimating the frequency offset of an LP signal within the preamble signal received based on the start point of the estimated preamble signal; a transmission mode detection unit for detecting a transmission mode based on the result of a cross-correlation function executed between between the received LP signal and the LP signal of three transmission modes; and an offset compensation unit for compensating for a frequency offset component of a data signal corresponding to a data area received after the LP signal and the LP signal received based on the estimated frequency offset.
Abstract:
PURPOSE: A communication method between the terminals in an infrastructure network and a resource assignment method thereof are provided to generate a small network in a specific area on a network including a wide coverage of an infrastructure network. CONSTITUTION: A terminal receives downlink data from a base station in a first time section by using a specific frequency band(910). The terminal transmits uplink data to the base station in a second time section by using the specific frequency band(920). The second time section is separated from the first time section. The terminal performs communication with one or more other terminals in a third time section by using the specific frequency band(930). The third time section is separated from the first and the second time section. [Reference numerals] (910) Receive resource allocation information; (920) Determine whether to communicate with another terminal; (930) Communicate with another terminal; (AA) Start; (BB) End
Abstract:
PURPOSE: A secondary transmitting station included in a cognitive radio communication system and a communication method of the station are provided to broaden a spectrum bandwidth selected by a secondary user by using a spectrum band not used by a primary user and a spectrum band used by the primary user together. CONSTITUTION: A secondary transmitting station estimates an interference channel between the secondary transmitting station and a primary user at each of one or more first spectrum bands used by a primary system(330). The secondary transmitting station calculates an orthogonal projection matrix(340). The secondary transmitting station calculates an effective channel between the secondary transmitting station and a secondary receiving station. The secondary transmitting station selects an index of an optimized spectrum band from one or more first spectrum bands based on the orthogonal projection matrix and the effective channel(350). [Reference numerals] (310) Sensing all spectrum bands available for primary users; (320) Spectrum band k is in use?; (330) Estimating interference channel g(k); (340) Calculating an orthogonal projection matrix P_g(k); (350) Selecting index k^ of an optimized spectrum band; (360) Regulating the covariance, R^_s, of a transmission signal; (370) Orthogonal projection matrix P_g(k) = identical matrix I_Nt; (380) Storing in order in a backup channel list, beginning the index of the optimized spectrum band; (AA) Start; (BB) End
Abstract:
PURPOSE: A heterogeneous communication system detection method and apparatus thereof are provided to determine kinds of heterogeneous communication system based on a system kind database by including silent duration information corresponding to the system kind database. CONSTITUTION: An RF(Radio Frequency) signal reception unit(201) receives signals from a specific communication system. A silent duration evaluation unit(202) evaluates silent duration between frames based on the received signals. A system kind determination unit(203) determines kinds of the specific communication system based on the evaluated silent duration. The specific communication system transmits data of a frame unit. The silent duration is respectively applied to the communication systems.
Abstract:
PURPOSE: A packet transmission method in a communication system and apparatus thereof are provided to improve transmission efficiency in a communication system by reducing protocol overheads. CONSTITUTION: A first apparatus requests permission to use a compressed packet before a second apparatus transmits a message(S210). The second apparatus transmits a specific preamble with the message for approving the usage of the compressed packet(S220). When the detection preparation of the specific preamble is completed, the first apparatus requests the packet to the second apparatus(S230). The second apparatus transmits the compressed packet by using the specific preamble(S240).
Abstract:
본 발명은 이종 네트워크 환경에서 무선단말기의 네트워크 자원 관리 방법에 관한 것으로, 본 발명에 따른 네트워크 자원 관리 방법은 이종 네트워크 환경에서 접속 가능한 하나 이상의 네트워크를 검색하는 단계와, 상기 네트워크 검색을 통해 검색된 네트워크들의 주기 정보를 획득하는 단계와, 상기 주기 정보를 토대로 상기 검색된 네트워크들의 공존 관리 주기를 결정하는 단계와, 상기 공존 관리 주기에 따라 검색된 네트워크들 중 데이터 전송에 이용할 하나 이상의 네트워크를 할당하고 그 할당된 하나 이상의 네트워크의 전송 관리 주기를 결정하는 단계와, 상기 공존 관리 주기 및 전송 관리 주기에 따라 상기 검색된 네트워크의 자원을 관리하는 단계를 포함한다.
Abstract:
The purpose of the present invention is to provide 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 receiving channel information based on location information, and facilitate efficient use of channels using the received information. The channel information providing method according to a preferable embodiment of the present invention, as a channel information providing method using a database server providing channel information to the cognitive radio terminal based on the location information, comprises: a provision step of providing information on a channel to at least one cognitive radio terminal; a reception step of receiving collected information on quality of the channel from the at least one cognitive radio terminal; and a determination step of updating the information on the channel provided in the provision step by using the information received in the reception step.