Abstract:
An apparatus for storing handover information in a mobile communication system is provided. The apparatus includes an estimation unit configured to estimate a direction of arrival (DOA) of a received signal with respect to a first base station based on the received signal, the received signal being received from a terminal belonging to the first base station, and a storage unit to store the estimated DOA as handover information associated with a second base station when the terminal is handed over to the second base station.
Abstract:
Provided are low-power wireless communication apparatuses and a method thereof. A hub may receive a beacon signal from a neighboring hub that is within a predetermined area from the hub, and control an operation of a node served by the hub based on information received from the neighboring hub.
Abstract:
Provided is a wireless communication system between medical devices. A wireless communication apparatus between medical devices using a cognitive technology may receive, from an external frequency coordination database server, state information of frequencies that are available in a predetermined area, and store interference information associated with the frequencies. The communication apparatus may sense an external interference signal that affects the frequencies outside the predetermined area, and an internal interference signal that affects the frequencies within the predetermined area. The communication apparatus may determine a priority of each of the frequencies that are available in the predetermined area based on the interference information, the external interference signal, and the internal interference signal, and may determine a frequency to be assigned based on the priority.
Abstract:
An interference determination apparatus, including a signal receiver to receive a first signal of a primary network and a second signal of a secondary network; a correlator to compute a correlation value of a first cyclic prefix included in the first signal and a correlation value of a second cyclic prefix included in the second signal; and an interference determination unit to determine an interference level or whether the interference occurs between the primary network and the secondary network, using the correlation value of the first cyclic prefix and the correlation value of the second cyclic prefix.
Abstract:
A cognitive radio communication apparatus and method which adaptably controls a sensing reference level based on a transmission power of a transmitter is provided. A cognitive radio communication apparatus includes a sensing reference level control unit to adaptably control a sensing reference level based on a transmission power of a secondary transmitter included in a secondary network, and a fast sensing unit to determine whether a signal received for a predetermined time period exists based on the controlled sensing reference level.
Abstract:
An operation method of a radio communication station is provided. The operation method of a radio communication station, the operation method including: transmitting a basic pilot signal to at least one terminal located in a coverage of a preoccupied system; and transmitting a cognitive radio (CR) pilot signal.
Abstract:
A cognitive radio terminal device. The cognitive radio terminal device comprises an available radio resource determination unit to determine an available radio resource from among up-link radio resources assigned to an up-link communication in a primary network, and an ad hoc communication performing unit to perform an ad hoc communication in a secondary network by using the available radio resource.
Abstract:
A communication method and apparatus of a cognitive radio (CR) environment using a relaying system while not interfering with a communication system having a priority right to use a frequency band, the communication method including: listening to fundamental channel (FCH) information and/or downlink/uplink (DL/UL) map information of a frame transmitted in the relaying system; obtaining a transmission signal of the relaying system using the FCH information and/or the DL/UL map information; orthogonally encoding data to be transmitted in the CR environment based on the obtained transmission signal; and transmitting the orthogonally encoded data via a determined channel that is used in the relaying system. Accordingly, aspects of the present invention can retrieve radio resources unused in the CR environment more easily.
Abstract:
A cooperative diversity method and apparatus that can minimize interference and maximize an efficiency of a transmission channel between terminals of a cooperative diversity pair, the method including: determining a pair of terminals to be a cooperative diversity pair according to a spectrum sensing result of a cognitive radio (CR); selecting a subchannel through which data is exchanged between the pair of terminals; and transmitting the data between the pair of terminals through the selected subchannel.
Abstract:
An apparatus and method for separating data units from a received concatenated burst in a wireless communication system, and an apparatus and method for generating a concatenated data unit during transmission. If a reception end receives the burst, it determines if each data of the burst is a header of the data unit, such that it can separate the data unit from the burst. A transmission end designates individual starting points of data units to be equal to an integer multiple position of a predetermined size, and constructs a concatenated format of the data units, such that it generates the burst.