Abstract:
An RF crossover structure includes a first and second independent transmission lines formed to cross with each other on a same surface of a dielectric substrate; first via-holes connected to the second transmission line so that the second transmission line is connected to a back surface from a front surface of the dielectric substrate and is connected again to the front surface of the dielectric substrate out of a crossing region at which the first and the second transmission lines are crossed. Further, the RF crossover structure includes CPW (Coplanar Waveguide) transmission lines used for a ground plane to improve a signal transmission property at the crossing region.
Abstract:
A communication method of a base station and a terminal based on interference alignment in a multi-cell multi-user multiple-input multiple-output (MIMO) interference channel and a method and apparatus of communication using interference alignment and block successive interference pre-cancellation in a multi-user MIMO interference channel. The base station may determine a precoding matrix to maximize a signal to interference and noise ratio (SINR) and a signal to leakage and noise ratio (SLNR) in the interference channel, and a terminal communicating with the base station may determine a decoding matrix to align interference. The transmitter including a multicell interference channel may calculate a rotation matrix for interference alignment, identify effective symbol vectors using the rotation matrix, and generate a transmit signal of a target transmitter to pre-cancel interference corresponding to a transmit signal of a neighboring transmitter.
Abstract:
A spatial modulation method using a polarization and an apparatus using the same are provided. A spatial modulation method by a transmitting apparatus in a wireless communication system may comprise selecting an antenna to send data among transmit antennas arranged to have different polarization angles using a predetermined bit of input data based on indexes of the transmit antenna and mapping remaining bits of the input data to a preset constellation and transmitting the remaining bits of the mapped input data through the selected antenna.
Abstract:
A device includes a feeding circuitry, a basic mode radiator for forming a basic mode main beam pattern having one or two orthogonal polarizations based on first two orthogonal inputs received from the feeding circuitry, and a higher-order mode radiator for forming a higher-order mode conical beam pattern having one or two orthogonal polarizations based on second two orthogonal inputs received from the feeding circuitry.
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:
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.
Abstract:
Disclosed is a communication method using interference alignment in a wireless local area network (WLAN). An access point (AP) according to one embodiment may receive first channel information between a station associated with the AP and the AP and second channel information between the station and a neighboring AP to perform interference alignment in cooperation with the AP from the station, and perform interference alignment based on the first channel information and the second channel information.
Abstract:
Provided are a data frame structure of a wireless communication system, which follows a sharing protocol which may be operated to coexist with a system that operates in an unlicensed spectrum, such as a WiFi system, and the like in the wireless communication system using a licensed spectrum such as an LTE system and an operation method of the system, and a terminal and a device of a base station for the operation.
Abstract:
Provided is a Tx and Rx array antenna apparatus with ultra high isolation, the Tx and Rx array antenna apparatus including N antenna elements, and a feeding network to provide electrical signals having identical amplitudes and opposite phases to antenna elements facing each other, among the N antenna elements.
Abstract:
Disclosed are a wireless communication method of improving frequency efficiency based on a channel function in a wireless communication system and an apparatus thereof. The wireless communication system using a digital modulation scheme, includes: a transmitting apparatus which modulates a data signal to generate a modulation symbol, generates a channel symbol function corresponding to the modulation symbol, combines the modulation symbol with the channel symbol function to generate a transmission symbol to transmit the generated transmission symbol through a transmission antenna; and a receiving apparatus which receives the transmission symbol through a reception antenna, estimates a channel symbol function included in the transmission symbol, and extracts the data signal based on the modulation symbol included in the transmission symbol.