Abstract:
A wideband transmitting and receiving apparatus including a local oscillator (LO) synthesizer providing a constant output to a wide band is provided. The LO synthesizer may generate LO signals of different amplitudes according to channels. The LO synthesizer may store the amplitudes of the LO signals different according to the channels and compensate the amplitudes of the LO signals using the stored amplitudes. Accordingly, the LO synthesizer may output the LO signals of uniform amplitudes irrespective of the channels.
Abstract:
Provided is a data transmission system using a carrier aggregation. The data transmission system may assign a radio resource based on a correspondence relationship between a downlink and an uplink, and may transmit data using the assigned radio resource.
Abstract:
Provided is a white space use system using a connection recognition signal, which is associated with technology that enables white space devices to search for and to use an available frequency band in a digital broadcasting system. In particular, provided is a white space use system using a connection recognition signal that enables even devices incapable of autonomously searching for an available channel to safely use a white space in interaction with white space devices.
Abstract:
Disclosed is a method for allocating a resource of a terminal. The method includes: receiving downlink data from a base station; and allocating a resource for a device-to-device communication to a sub-frame by considering a hybrid ARQ (HARQ) transmission delay with respect to the received downlink data.
Abstract:
Disclosed is a network management apparatus for priority channel assignment to acquire available channels in a frequency sharing band, including: a signal intensity measurer measuring a received signal intensity for an input signal; and a controller verifying usable candidate channels in the same channel and an adjacent channel of a TV band device (TVBD) for each predetermined frequency based on the measured received signal intensity, verifying available channels of the TVBD based on the verified usable candidate channels in the same channel and the adjacent channel, calculating the decreased number of available channels of the TVBD predicted for each channel after channel reassignment, and assigning channels to be reassigned based on the calculated decreased number of available channels of the TVBD.
Abstract:
An exemplary embodiment provides a carrier aggregation apparatus including: a level assignment manager configured to perform management by classifying a license band allocated to a cognitive radio cell into a primary radio resource (PRR) level, and by classifying a shareable band obtained through a cognitive radio database or spectrum sensing into an auxiliary radio resource (ARR) level; a determiner configured to determine a quality of service (QoS) level of a communication service provided to the cognitive radio cell; and a service provider configured to allocate a frequency resource of the PRR level when the QoS level requires a first communication service, and to allocate a frequency resource of the ARR level when the QoS level requires a second communication service lower than the first communication service.
Abstract:
Disclosed is a method for generating and transmitting a reference signal in a clustered DFT-spread OFDM transmission scheme. A method for generating and transmitting a DM-RS in a clustered DFT-spread-OFDM scheme comprises: a step of generating DM-RS sequences corresponding to the number of clusters allocated for an uplink transmission; and a step of mapping the generated DM-RS sequences to the relevant DM-RS symbol positions for each cluster. Accordingly, the method for generating and transmitting a reference signal according to the present invention, in which DM-RS sequences are allocated and transmitted on a cluster basis, uses a complete DM-RS sequence for each cluster, and therefore inter-cell interference can be weakened, and problems which might occur when applied to a multi-user MIMO (MU-MIMO) scheme can be solved.
Abstract:
Provided is a data transmission system using a carrier aggregation. The data transmission system may assign a radio resource based on a correspondence relationship between a downlink and an uplink, and may transmit data using the assigned radio resource.
Abstract:
A wireless communication method may include performing, by a first system, channel monitoring of a first band, detecting a second system that uses the first band, determining whether the first system is to be used in preference to the second system, and allocating a radio resource of the first band to the first system based on whether the first system is to be used in preference to the second system.
Abstract:
Disclosed is a method of allocating radio resources, including: acquiring available channel information of a cognitive radio small cell; analyzing a channel characteristic based on the available channel information and dividing a required transmission rate of the cognitive radio small cell into required transmission rates for each available channel; and performing a power control for each available channel based on the divided required transmission rates for each available channel. The method of allocating radio resources may be performed under an interference environment in which a plurality of cognitive radio small cells is present and the plurality of cognitive radio small cells shares an available channel.