Abstract: It is provided a wireless communication system comprising base stations that transmit data to a terminal with cooperation by the base stations. The terminal communicates with the base stations. The terminal periodically transmits, to one of the base stations, information necessary for data transmission from a single base station out of the base stations. Each of the base stations determines whether the terminal needs data transmission through a cooperation among the base stations, and transmits a cooperation information transmission instruction to the terminal, which includes information necessary to execute the data transmission in order to cooperate among the base stations in the case where it is determined that the terminal needs the data transmission through the cooperation among the base stations. The terminal transmits the cooperation information to the base stations in a case of receiving the cooperation information transmission instruction.

Abstract: It is provided a wireless communication system comprising base stations that transmit data to a terminal with cooperation by the base stations. The terminal communicates with the base stations. The terminal periodically transmits, to one of the base stations, information necessary for data transmission from a single base station out of the base stations. Each of the base stations determines whether the terminal needs data transmission through a cooperation among the base stations, and transmits a cooperation information transmission instruction to the terminal, which includes information necessary to execute the data transmission in order to cooperate among the base stations in the case where it is determined that the terminal needs the data transmission through the cooperation among the base stations. The terminal transmits the cooperation information to the base stations in a case of receiving the cooperation information transmission instruction.

Abstract: A radio communication system using an orthogonal frequency division multiplexing system, including: a baseband unit; and one or plural remote radio units coupled with the baseband unit through an interface; wherein the baseband unit includes a first sample frequency conversion part that performs a first sample frequency conversion processing that down-samples a transmitting signal transmitted through the interface, wherein the remote radio unit includes a second sample frequency conversion part that performs a second sample frequency conversion processing that up-samples a signal received through the interface, and wherein the baseband unit further includes an inverse fast fourier transform part that generates the transmitting signal by an inverse fast fourier transform, and a transmitter characteristic compensation part that conducts frequency characteristic compensation of the first sample frequency conversion processing and the second sample frequency conversion processing for a signal that has not been su

Abstract: Ameliorate deterioration in quality of communication caused by intercell interference with respect to a multicarrier communications protocol, such as OFDM. A method of positioning an error correction-coded signal is changed with a data symbol that is transmitted simultaneously with a pilot signal and a data symbol that is not simultaneous with the pilot symbol. Else, a modulation protocol is changed with a data symbol that is transmitted simultaneously with a pilot signal and a data symbol that is not simultaneous with the pilot symbol. It would further be permissible to lower either a signal amplitude or a power level of a data symbol that is transmitted simultaneously with a pilot signal.

Abstract: A method for radio resource control is carried out in a radio communications system including multiple base stations. In this method, a radio resource that can be used by the base stations is divided into multiple first radio resources on the frequency axis. Then one or more of the first radio resources are allocated to a second radio resource for initially transmitting a packet and the other first radio resources are allocated to a third radio resource for retransmitting the packet.

Abstract: A base station is connected to wired and wireless networks to send a call that is received from the wired network to the wireless network at a predetermined quality of service (QoS), select one or more combinations of a set of modulation and coding scheme, and a radio resource amount that are associated with a QoS set in a newly incoming call, determine the radio resource amount that is equal to or less than a amount of the unassigned radio resources, assign, to the newly incoming call, the combination that is associated with the determined radio resource amount and the QoS set in the newly incoming call, reduce the radio resources assigned to the ongoing call without changing the QoS, and assign, to the newly incoming call, an amount of radio resources released from the ongoing call and modulation and coding scheme associated with this released radio resource amount.

Abstract: Conventionally, different HARQ processes 801 and 802 (subframes T1 and T2) transmit data packets B and D, respectively. One data packet corresponds to one process and is retransmitted as necessary one by one on a process basis, degrading the usage efficiency of frequency and time resources. To solve this problem, downlink data packets B and D, when needed to be retransmitted, are spatially multiplexed in the different HARQ processes 801 and 802. The data packets are simultaneously retransmitted to the same terminal as process 805 (subframe T3).

Abstract: A radio communication system using an orthogonal frequency division multiplexing system, including: a baseband unit; and one or plural remote radio units coupled with the baseband unit through an interface; wherein the baseband unit includes a first sample frequency conversion part that performs a first sample frequency conversion processing that down-samples a transmitting signal transmitted through the interface, wherein the remote radio unit includes a second sample frequency conversion part that performs a second sample frequency conversion processing that up-samples a signal received through the interface, and wherein the baseband unit further includes an inverse fast fourier transform part that generates the transmitting signal by an inverse fast fourier transform, and a transmitter characteristic compensation part that conducts frequency characteristic compensation of the first sample frequency conversion processing and the second sample frequency conversion processing for a signal that has not been su

Abstract: A radio communications system includes at least one terminal communication unit having one antenna that conducts a radio communication with a plurality of terminals; and at least one baseband modem that generates and decrypts a data signal, a cell being configured by at least one of the antenna, wherein the baseband modem divides a radio frequency band used for the radio communication into two or more subbands, generates and decrypts the data signal specific to each of the divided subbands, and allocates the data signal specific to the subband to the terminal communication unit, and wherein the terminal communication unit receives the data signal specific to the subband generated by the baseband modem, and forms the cell of each the subband by the data signal specific to the received subband.

Abstract: A signal frequency of an interface signal between a baseband unit and a remote radio unit is decreased by downsampling, and the strain of the signal caused by downsampling is compensated for each subcarrier before an IFFT during transmission, and after FFT during reception.

Abstract: A wireless communication method in which a base station and a wireless terminal communicate, including: an operation at which a first and a second base station transmit, for each beam area, a pilot signal including identification information to identify the base station and the beam area, in a beam pattern; an operation at which the wireless terminal obtains received power of each pilot signal; an operation at which the wireless terminal causes one of the beam areas of the first base station to be a desired wave beam area, and determines two data rates for requiring to the base station: one of the data rates being a first data rate used in a case that interference from the second base station is relatively high and another of the data rates being a second data rate used in a case that the interference from the second base station is relatively low.

Abstract: In wireless communication systems into which a relay device has been introduced, although terminal reception quality increases, data transmission by relay devices with low contribution causes interference in other data transmission, which invites a decrease in reception quality of electromagnetic waves received by terminals. As a way to resolve the abovementioned issue, as one embodiment of the present disclosures, a wireless relay station is configured so as to receive a plurality of data addressed for wireless terminals from a wireless base station, and to transmit data that are selected from the aforementioned received plurality of data and that are addressed to the aforementioned wireless terminals which are the destinations of transmission. As a result, interference towards other data transmission and reception caused by data transmission of a relay device can be suppressed, and the reception quality of electromagnetic waves received by the terminal can be increased.

Abstract: A non-terminated packet is transmitted, by utilizing a spatial layer responded with an ACK, which is assumed as a released layer. Alternatively, a non-terminated packet is transmitted by using a released layer and an original spatial layer in combination. Alternatively, a new packet is transmitted in a released layer by utilizating time till termination of transmission of a non-terminated packet. A wireless communication system effectively utilizing a released layer, a terminal and a base station.

Abstract: Provided is a wireless base station comprising: a power control unit, a reference information acquisition unit and a reference information storing unit, wherein the wireless base station comprises a first control signal receiving unit for receiving a first uplink control signal used by a mobile station connected to the wireless base station and for requesting the power control unit to control the transmission, and a second control signal receiving unit for receiving a second uplink control signal used by a mobile station connected to the neighbor base station and for requesting the power control unit to control the transmission power, and wherein the power control unit controls the transmission power of the downlink signal based on the request to control the transmission power from the first control signal receiving unit and the request to control the transmission power from the second control signal receiving unit.

Abstract: When a receiving apparatus which employs a OFDM-based cellular wireless communication scheme detects as an excessive signal for each frame, the signal having signal intensity exceeding a reference value after a Fourier transform, a gain variable according to an excessive quantity relative to the reference value is used for each frame to control signal intensity such that the amplitude thereof is at most the reference value.

Abstract: It is provided a wireless communication system comprising base stations that communicate with a terminal. Each of the base station has antennas. Each of the base stations transmits a first reference signal unique to each of the antennas which does not overlap with another antenna among the base stations at least in a vicinity thereof. The terminal receives the first reference signal and estimates a received power of the first reference signal for each of the antennas, selects antennas suitable for communication from among the antennas based on a result of estimating the received power, and transmits a result of selecting the antennas to the each of the base stations. The each of the base stations refers the result of selecting the antennas transmitted from the terminal, assigns the selected antennas belonging to different cells to the terminal, and notifies the terminal of a result of assigning the antennas.

Abstract: It is provided a wireless communication system comprising base stations that transmit data to a terminal with cooperation by the base stations. The terminal communicates with the base stations. The terminal periodically transmits, to one of the base stations, information necessary for data transmission from a single base station out of the base stations. Each of the base stations determines whether the terminal needs data transmission through a cooperation among the base stations, and transmits a cooperation information transmission instruction to the terminal, which includes information necessary to execute the data transmission in order to cooperate among the base stations in the case where it is determined that the terminal needs the data transmission through the cooperation among the base stations. The terminal transmits the cooperation information to the base stations in a case of receiving the cooperation information transmission instruction.

Abstract: Ameliorate deterioration in quality of communication caused by intercell interference with respect to a multicarrier communications protocol, such as OFDM. A method of positioning an error correction-coded signal is changed with a data symbol that is transmitted simultaneously with a pilot signal and a data symbol that is not simultaneous with the pilot symbol. Else, a modulation protocol is changed with a data symbol that is transmitted simultaneously with a pilot signal and a data symbol that is not simultaneous with the pilot symbol. It would further be permissible to lower either a signal amplitude or a power level of a data symbol that is transmitted simultaneously with a pilot signal.

Abstract: A wireless communication method in which a base station and a wireless terminal communicate, including: an operation at which a first and a second base station transmit, for each beam area, a pilot signal including identification information to identify the base station and the beam area, in a beam pattern; an operation at which the wireless terminal obtains received power of each pilot signal; an operation at which the wireless terminal causes one of the beam areas of the first base station to be a desired wave beam area, and determines two data rates for requiring to the base station: one of the data rates being a first data rate used in a case that interference from the second base station is relatively high and another of the data rates being a second data rate used in a case that the interference from the second base station is relatively low.

Abstract: It is provided a base station for providing a wireless communication area, which is coupled to a core network via a gateway, including: an interface for receiving settings of availability of allocation to terminals located in a border area of the wireless communication area and availability of allocation to terminals located in an area other than the border area for each of radio resource blocks which are defined by dividing radio resources available for use in the wireless communication area provided by the base station into predetermined units; and a plurality of profiles for defining scheduling limitations on the radio resources in the number of the profiles of patterns, being set via the interface, in which the base station applies scheduling limitations defined by the profile designated with the identifier and allocates the radio resources upon designation of one of the plurality of profiles with an identifier.