Abstract: Provided is a method of allocating a resource in a small cell system. The method includes: selecting a temporary base station for each user terminal; measuring a signal-to-noise ratio (SNR) through a downlink pilot in a small cell base station; transmitting the signal-to-noise ratio measured for each user terminal to the temporary base station; receiving base station selection and resource allocation information from the small cell base station; and selecting the small cell base station to which most frequency resource block are allocated as a home base station.

Abstract: An apparatus and method for controlling interference between small-cell base stations by using multi-antenna beamforming. The apparatus includes a channel state information (CSI) estimator, a non-optimal beamforming factor calculator, an optimal beamforming factor calculator, and an interference controller. The apparatus and method control interference between small-cell base stations by calculating an optimal beamforming factor assuming that information exchange between base stations is limited in a small-cell downlink system and each base station knows only a channel value sent by itself or a channel value received by itself.

Abstract: Provided is a method of allocating a resource in a small cell system. The method includes: selecting a temporary base station for each user terminal; measuring a signal-to-noise ratio (SNR) through a downlink pilot in a small cell base station; transmitting the signal-to-noise ratio measured for each user terminal to the temporary base station; receiving base station selection and resource allocation information from the small cell base station; and selecting the small cell base station to which most frequency resource block are allocated as a home base station.

Abstract: A method and apparatus for estimating a channel in a frequency domain are provided. The apparatus acquires frequency selectivity information using a cell-specific reference signal, selects a channel estimation scheme using a user specific reference signal according to the acquired frequency selectivity information, and estimates a frequency channel using the selected channel estimation scheme. Accordingly, more accurate channel estimation with respect to a region to which a physical downstream shared channel is allocated can be performed.

Abstract: A method and apparatus for estimating a channel in a frequency domain are provided. The apparatus acquires frequency selectivity information using a cell-specific reference signal, selects a channel estimation scheme using a user specific reference signal according to the acquired frequency selectivity information, and estimates a frequency channel using the selected channel estimation scheme. Accordingly, more accurate channel estimation with respect to a region to which a physical downstream shared channel is allocated can be performed.

Abstract: The present invention relates to a method of transmitting/receiving random access response information in a radio communication system, and a base station and a terminal thereof. According to the invention, in a case where a base station of a radio communication system transmits response information for random access processing requested from terminals, the base station determines whether to transmit non-contention-based response information and contention-based response information for each of one or more terminals, which requests random access, by one radio resource. When determining to be transmitted by one radio resource, the base station transmits the random access response information configured by the non-contention-based response information and the contention-based response information for each of one or more terminals.

Abstract: The present invention relates to a wireless communication system having protocol architecture for reducing latency of a cellular system. In the protocol architecture of the wireless communication system in the cellular system, a physical layer supports wireless transmission of the cellular system and estimates a radio channel condition. A data link layer determines a data transmission mode based on a QoS of user data and the radio channel condition estimated by the physical layer and performs segmentation and assembly of the packet data, and a network layer establishes and releases a radio bearer for transmitting packet data transmitted from the data link layer and a control command. A control service access point is provided for control information transmission between the data link layer and the physical layer.

Abstract: A terminal state controlling method and apparatus are provided. The terminal state includes a connected state and an idle state, and the connected state includes an active state and a dormant state. The active state includes a scheduling-ON state and a scheduling-OFF state. In the state controlling apparatus, a radio resource control (RRC) layer controls a transition between the active state and the dormant state, and a media access control (MAC) layer controls a transition between the scheduling-ON state and the scheduling-OFF state.