Abstract: A user apparatus according to an embodiment is provided. The user apparatus communicates with a base station in a wireless communication system. The user apparatus includes an obtaining unit configured to obtain resource allocation information in which downlink signal reception quality is associated with radio resources used for uplink signal transmission; a measurement unit configured to measure the downlink signal reception quality; and a transmission unit configured to determine a radio resource of the radio resources used for uplink signal transmission by comparing the resource allocation information with the measured downlink signal reception quality, and transmit an uplink signal by using the determined radio resource.

Abstract: The present disclosure relates to techniques for reducing flash light effect in 3D MIMO. One aspect of the present invention relates to user equipment, comprising: a transmission and reception unit configured to receive an interference beam candidate list including directional beams transmitted from a camped base station and interference beam candidates transmitted from an adjacent base station; a measurement unit configured to measure reception quality of reference signals transmitted in the respective directional beams in the received interference beam candidate list; and an interference information generation unit configured to generate interference information based on the measured reception quality, wherein the transmission and reception unit indicates the generated interference information to the camped base station or the adjacent base station.

Abstract: The present invention is directed to efficiently transmitting feedback control information in a physical uplink control channel in a communication system having a system band formed with a plurality of fundamental frequency blocks.

Abstract: The object is achieved by providing a base station apparatus for performing time and frequency scheduling in uplink packet access with: an interference amount measurement part configured to measure an uplink interference amount for each interference amount measurement unit which comprises a predetermined period and a predetermined number of frequency blocks; an interference amount determination part configured to determine whether the uplink interference amount satisfies a predetermined condition; and an overload indicator reporting part configured to report an overload indicator to a neighboring cell when the predetermined condition is satisfied.

Abstract: To suppress decrease in throughput even in the case where downlink transmit power is controlled, a user terminal according to one aspect of the present invention has a reception section that receives information on a candidate for downlink transmit power, a generating section that selects a plurality of candidates for downlink transmit power to generate CSI (Channel State Information) on the plurality of candidates for downlink transmit power, and a transmission section that transmits the CSI on the plurality of candidates for downlink transmit power.

Abstract: The present invention is designed to enable uplink signal transmission power control that is suitable when non-orthogonal multiple access (NOMA) is used on the uplink.

Abstract: To reduce a reception processing load, while obtaining gain of Non-Orthogonal Multiple Access (NOMA), in the case of transmitting a downlink signal using the NOMA scheme, a user terminal according to one aspect of the present invention is provided with a transmission section that transmits a plurality of precoding matrix indicators (PMIs) to a radio base station, and a reception section that receives, from the radio base station, a downlink signal that is non-orthogonally multiplexed with a downlink signal to another user terminal determined based on the plurality of PMIs and that is multiplied by the same precoding matrix as that of the downlink signal to another user terminal.

Abstract: A base station that communicates with a mobile station by using a plurality of antenna ports includes a mapping information communication unit configured to generate mapping of reference signals for measuring channel state information of the antenna ports. The base station applies identical mapping of the reference signals for measuring the channel state information to antenna ports included in any one group of the plurality of groups, while applying code division multiplexing to the reference signals for measuring the channel state information for the antenna ports. The base station applies different mappings of the reference signals for measuring the channel state information and communicates information indicating the generated mapping to the mobile station. The base station also includes a multiplexer to multiplex the reference signals in accordance with the generated mapping and a transmitter to transmit the reference signals for measuring the channel state information.

Abstract: To suppress deterioration of reception characteristics of a user terminal even in the case where a radio base station performs power multiplexing on downlink MIMO signals to transmit, a radio base station according to one aspect of the present invention has a transmission section that performs power multiplexing on downlink signals to a plurality of user terminals each having a MIMO (Multiple-Input Multiple-Output) configuration to transmit, and a control section that controls a PMI (Precoding Matrix Indicator) and/or an RI (Rank Indicator) applied to the downlink signals, where the transmission section transmits information on the PMI and/or the RI of another user terminal subjected to power multiplexing to a predetermined user terminal.

Abstract: A mobile station includes: a physical channel segmentation unit to receive radio signals including multiple orthogonal signals which are orthogonal to each other, and multiple non-orthogonal signals which are not orthogonal to each other; and data demodulating/decoding units to extract the non-orthogonal signal addressed to the mobile station from the multiple non-orthogonal signals by demodulating and cancelling the radio signal addressed to another mobile station by use of the orthogonal signals included in the radio signals received by the physical channel segmentation unit, and demodulate the signal included in the orthogonal signals and addressed to the mobile station, and the extracted non-orthogonal signal addressed to the mobile station.

Abstract: A user equipment used in a mobile communication system that has multiple antenna ports configured to receive a first reference signal from a base station is disclosed. The antenna ports are configured to transmit the first feedback information for the first reference signal. Additionally, the antenna ports are configured to receive a second reference signal from the base station and transmit the second feedback information for the second reference signal.

Abstract: A user terminal selects small cells in a radio communication system in which a macro cell and small cells are arranged to overlap each other. In the cell selection method of the present invention, a macro base station to form a macro cell carries out the steps of determining the offset value to use in cell selection in a user terminal based on transmission property information of a second carrier in the small cell, and reporting the offset value to the user terminal. Also, the user terminal carries out the steps of measuring the received quality of reference signals from the macro base station and the small base station, receiving the offset value that is reported from the macro base station, and carrying out cell selection based on the received quality that is measured and the offset value that is received.

Abstract: A user apparatus includes a transmission/reception circuit that transmits an uplink signal and receives a downlink signal; and a control circuit that switches to transmitting, as the uplink signal, an uplink control signal or a random access channel signal within a time interval configured of a plurality of symbols, after a given interval that is provided to prevent transmission of the uplink signal and reception of the downlink signal from overlapping each other within the time interval, by using a format in which first several symbols are blanked in the time interval.

Abstract: The object is achieved by providing a base station apparatus for performing time and frequency scheduling in uplink packet access with: an interference amount measurement part configured to measure an uplink interference amount for each interference amount measurement unit which comprises a predetermined period and a predetermined number of frequency blocks; an interference amount determination part configured to determine whether the uplink interference amount satisfies a predetermined condition; and an overload indicator reporting part configured to report an overload indicator to a neighboring cell when the predetermined condition is satisfied.

Abstract: In switching a radio base station (SeNB) from a radio base station (SeNB#1) to a radio base station (SeNB#2) in an “Inter-node UP aggregation”, forwarding of new downlink data destined for a mobile station (UE) from a radio base station (MeNB) to the radio base station (SeNB#2) is quickly started. A mobile communication method according to the present invention includes: sending, by the mobile station UE, the radio base station (MeNB) a “New data delivery request” that requests forwarding of new downlink data destined for the mobile station (UE) to the radio base station (SeNB#2), in response to an “SeNB change command”; and forwarding, by the radio base station MeNB, the new downlink data destined for the mobile station (UE) to the radio base station (SeNB#2), in response to the “New data delivery request”.

Abstract: The present invention is designed to provide highly efficient local area radio access. A communication system, in which a mobile terminal apparatus (10) detects a local area base station apparatus (30) to connect to, among local area base station apparatuses (30), is configured such that the local area base station apparatuses (30) transmit detection signals to be used to detect the local area base station apparatus (30), to the mobile terminal apparatus (10), in a radio communication scheme for the local areas, which is different from the radio communication scheme for the wide area, and the mobile terminal apparatus (10) transmits detection signal measurement results to the local area base station apparatus (30), through an uplink channel that is defined in the radio communication scheme for the local areas.

Abstract: A radio communication system includes a radio base station and a terminal device. The radio base station and the terminal device share correspondence information about subsets of preamble sequences obtained by segmenting preamble sequences available in the radio communication systems into groups, each of the subsets being associated with a received signal level at the terminal device and a number of repetitions for transmitting the preamble sequences of each of the subsets. Based upon a receive level of a signal transmitted from the radio base station, the terminal device selects a subset corresponding to the receive level by referring to the correspondence information and transmits a preamble sequence included in the selected subset at the number of repetitions associated with the selected subset.

Abstract: The present invention is designed to shorten the time that a user terminal takes to detect the common control/reference signals while coverage of the common control/reference signals transmitted from a small base station is secured. As the radio communication method of the invention, a radio communication method is provided in which beam forming information for forming transmission beams directed from the small base station to the user terminal are generated based on position-related information of the user terminal acquired by communication between the macro base station and the user terminal using a coverage carrier and position-related information of the small base station, and the small base station precodes at least one of a common control signal and a reference signal that are common in a small cell based on the beam forming information and transmits the precoded signal from a plurality of transmitting antennas using a capacity carrier.

Abstract: A system and method for allocating adequate uplink radio resources for delivery acknowledgement information of a downlink shared data channel when downlink control information is transmitted using an enhanced downlink control channel is disclosed. A radio base station configures a plurality of enhanced PDCCH sets, which are each formed to include a plurality of enhanced control channel elements (eCCEs) allocated to the enhanced downlink control channel, for a user terminal, the radio base station transmits, to the user terminal, the downlink control information, to which resource identifiers (ARIs) are added, the resource identifiers being different between the plurality of enhanced PDCCH sets, and the user terminal determines radio resources for an uplink control channel that are used to transmit delivery acknowledgment information of the downlink shared data channel, based on offset values that are associated with the resource identifiers (ARIs).

Abstract: A user device receives, from a base station, a radio signal in which non-orthogonal signals are mixed. The user device recognizes, based on information transmitted from the base station, a parameter associated with the location of the user device. When the user device is at the edge of the cell area of the base station, a demodulator of the user device demodulates, as a signal directed to the user device, the radio signal in which an interference signal component has been suppressed by an interference rejection combining processor of the user device and a non-orthogonal signal canceller of the user device does not operate.