Ntt Docomo, Inc.

Nec Corporation

Agency for Science, Technology and Research

Hiroyuki Atarashi

Mamoru Sawahashi

Kenichi Higuchi

Sadayuki Abeta

Motohiro Tanno

Noriyuki Maeda

Nobuhiko Miki

Yoshihisa Kishiyama

Teruo Kawamura

Yoshiaki Ofuji

Yoshikazu Kakura

Yoshikazu Goto

Koichi Okawa

Shingo Suwa

Satoshi Nagata

Wuri Andarmawanti Hapsari

Shousei Yoshida

Fumiyuki Adachi

Zhongding Lei

Kengo Yagyu

Takehiro Ikeda

Takahiro Takiguchi

Ying-Chang Liang

Francois Po Shin Chin

Xiaoming Peng

Soulisak Ormsub

An object is to improve the throughput of a mobile station UE without affecting the coverage of a macrocell in a case where CA is introduced to a HetNet environment. A radio base station eNB according to the present invention is configured to determine whether or not to change the connection destination of a mobile station UE from a small cell #to a small cell #while the mobile station UE is performing CA by using the macrocell and the small cell #, based on at least one of the congestion status in each of the small cell #and the small cell #and the communication quality in each of the small cell #and the small cell #

Radio base station

A transmission apparatus is provided with radio resource assignment means that assigns radio resources to each physical channel according to a type of the physical channel; and transmission means that transmits information to be transmitted by each physical channel using the assigned radio resources.

Transmission apparatus and radio resource assignment method

Transmitting apparatus and radio resource assignment method

In a radio communication system, a downlink frequency band includes a plurality of frequency blocks including one or more carrier frequencies, and one or more frequency blocks are used for data transmission to a single user. A radio communication apparatus for use in the communication system has an evaluation unit evaluating the quality of a received signal for each frequency block and storing plurality of stored quality evaluations of the received signal, a comparison unit comparing the plural quality evaluations of the received signal, and a transmission unit transmitting a predetermined number of the quality evaluations of the received signal over an uplink control channel.

Radio communication apparatus and method

In a radio communication system defining a plurality of bandwidths, mobile terminals of kinds respectively corresponding to the plurality of bandwidths are accommodated in the system, and a minimum transmission bandwidth of the plurality of bandwidths is set as a transmission bandwidth of a downlink common channel. Or, every mobile terminal accommodated in the radio communication system is provided with a capability for processing a bandwidth equal to or greater than a predetermined value, and equal to or more than two transmission bandwidths that are equal to or less than a predetermined value are set as a transmission bandwidth of a downlink common channel. In the latter case, the mobile terminal identifies a bandwidth of a received downlink common channel.

Transmission and reception bandwidth setting method, mobile terminal and base station in radio communication system that defines a plurality of signal bandwidths

A radio resource assignment method for a physical channel in an uplink directed from a mobile apparatus to a base station in a radio communication system, includes: assigning a contention-based channel and a scheduled channel according to one of a time division scheme, a frequency division scheme, and a hybrid scheme of the time division scheme and the frequency division scheme. In addition, radio resources are properly assigned to each of the contention-based channel, a common control channel of the scheduled channel, and a shared data channel of the scheduled channel.

Radio resource assignment method for physical channel in uplink, and transmitter for mobile apparatuses

The present invention is directed to a channel structuring method that includes a step of providing time frames segmented at a predetermined interval in communication channels of n subcarriers, a step of selecting a predetermined number of subcarriers from n subcarriers and a step of inserting a common control channel signal and a common pilot signal periodically into each of the time frames of the selected subcarriers.

Channel structuring method and base station therewith

A transmitter comprises a first spreading unit configured to multiply each of multiple data symbols with a first spreading code sequence of a first spreading factor; a compression and repetition unit configured to compress output signals of the first spreading unit in time domain and repeat the compressed signal L times (where L is a natural number greater than or equal to 2); a phase modulation unit configured to multiply the compressed and repeated signal with a user dependent phase and output a data block consisting of L sub-blocks; a second spreading unit configured to replicate the data block according to a second spreading factor and multiply each set of the replicated sub-blocks with a second spreading code sequence of the second spreading factor to produce a two-dimensionally spread signal; and a wireless transmission unit configured to transmit the two-dimensionally spread signal using a single-carrier transmission scheme.

Two-dimensional code spreading for interleaved FDMA system

A base station includes: means that derives a transmission power of a mobile station based on receive quality of an uplink pilot channel; means that reports the derived transmission power to the mobile station; and means that receives a control channel transmitted by the mobile station according to the reported information. Accordingly, irrespective of transmission power history over a past continuous time, the mobile station receives an instruction on the transmission power from the base station each time when transmitting a packet so as to be able to adjust the transmission power.

Base station, mobile station, and power control method

An apparatus determines a transmission bandwidth for uplink transmission of a signal and includes a reception unit that receives a predefined signal from a mobile station and derives a channel quality indicator based on the received signal. The apparatus also includes a storage unit that stores a relationship between the channel quality indicator and the transmission bandwidth of the mobile station. The apparatus also includes a determination unit that determines the transmission bandwidth based on the relationship and a transmission unit that transmits the transmission bandwidth to the mobile station.

Apparatus and method for determining uplink transmission parameters

A transmission apparatus which attempts improvement of signal quality in an uplink and a downlink carries out radio transmission of different signals simultaneously from respective ones of a plurality of antennas. The apparatus has pilot multiplexing means for multiplexing a pilot channel to transmit from each antenna in one or more of a time division multiplexing method, a frequency division multiplexing method and a code division multiplexing method, data multiplexing means for time-multiplexing a pilot channel and a data channel, and means for transmitting a signal in a least one of a space division multiplexing (SDM) method and a space time transmission diversity (STTD) method.

Transmission apparatus, transmission method, reception apparatus and reception method

A disclosed transmission apparatus comprises a switching portion that switches radio access methods; a frequency domain signal generation portion that allocates a radio resource to a spread chip sequence on which one of a fast Fourier transformation and a series/parallel conversion is performed in accordance with the switched radio accessed method, so as to generate a signal in a frequency domain; and a transmission signal generation portion that performs a fast inverse Fourier transformation on the signal in the frequency domain so as to generate a transmission signal.

Transmission apparatus, reception apparatus, mobile communications system and transmission control method

A transmitter includes: spread code multiplying means that multiplies a symbol indicating a reference signal by spread code to generate a chip sequence after spreading; chip pattern generation means that generates a chip pattern by performing chip repetition a predetermined repetition number of times on the chip sequence after spreading; and multiplying means that multiplies a signal having the chip pattern by a phase specific to the transmitter.

Growing community of inventors

Yokohama, Japan

Hiroyuki Atarashi