Abstract: The present disclosure relates to cached-data obtaining methods, devices, and communications systems. One example method includes receiving a request data packet from a user terminal, where the request data packet is used to request target data from an over the top server, determining, based on a first data cache list, whether information about the request data packet matches information in the first data cache list, and if the information about the request data packet matches the information in the first data cache list, sending the target data to the user terminal.

Abstract: A base station performs an association between frequency range and combinations of a plurality of base stations including an local base station to notify a terminal of the association. According to the notified association, the terminal, for each frequency, calculates quality of communication with one base station or quality of communication with the combination of the plurality of base stations. The base station and the control station determine the base station/the plurality of base stations that communicate with the terminal, the wireless resource and the transmission scheme, based on the result. Further, the base station selects whether to notify an entirety of or a part of the association to the terminal using positional information of the terminal. Since the association information that is unnecessary for the terminal is not communicated, it is possible to further lighten the load of control.

Abstract: It is provided a base station apparatus that uses a plurality of coordinated Multiple Points (CoMP) schemes, and is connected to a plurality of subordinate transmission points for transmitting data, comprising: a transceiver unit, located at the transmission point, that receives and transmits data from and to a terminal; a data processing unit that extracts non-periodic feedback information and periodic feedback information from the data received via the transceiver unit from the terminal; a CoMP scheme selection unit that selects a CoMP scheme to be applied to the terminal from a plurality of CoMP schemes based on the non-periodic feedback information; and a scheduling unit that performs scheduling with use of the selected CoMP scheme based on the non-periodic feedback information and periodic feedback information, and transmits data to the terminal via a corresponding transceiver unit.

Abstract: A base station broadcasts a message saying that transmittable ranging codes are limited by antenna IDs to limit antennas and the ranging codes to be searched, thereby reducing a processing load of the search. In a cellular radio communication system in which a base station device is connected to plural antennas, and antenna IDs for identifying the antennas are transmitted from the respective antennas, the base station device broadcasts a message saying that a group of ranging codes transmittable by a terminal device is limited by the antenna IDs, the terminal device receives the message, identifies the antenna ID, selects the ranging code from the group of the ranging codes corresponding to the antenna ID, and transmits the selected ranging code.

Abstract: In an environment in which a macro base station and a low transmission power base station exist, the ratio of the interference reduction time period of the macro base station is optimized, and the throughput of the low transmission power base station is improved, while minimizing a reduction in throughput. The macro base station causes a high interference to other base stations and one or a plurality of low power nodes (LPN) subjected to interference from the macro base station. The macro base station sets first and second data transmission time periods and then determines the ratio of the second time period and the pattern of the first time period and the second time period based on communication quality in the first time period and communication quality in the second time period of the macro base station and the LPN.

Abstract: A frame time having a certain period of time is divided into: a time period (for inter-base-station time division multiplex communication) in which one of the base stations has a transmission right in the simultaneous transmission and carries out inter-base-station time division multiplex communication so as to avoid interference between the base stations; and a time period (for inter-base-station simultaneous communication) for communication which is simultaneously carried out between the plurality of base stations. Furthermore, the time periods are switched for the communication.

Abstract: Disclosed are a communication control device, a communication control method and the system thereof, which provide efficient multi-base station joint services in a mobile communication system using dynamic clustering. Optimal base station clustering is chosen according to the communication state between a terminal and each base station. The communication control device connects with multiple base stations through a network, and clusters the multiple base stations dynamically so that the clustered multiple base stations can provide services for the mobile terminal in union. The communication control device comprises: an interface, connecting with multiple base stations, receiving channel state information related to the mobile terminal from each base station; a memory unit, storing the channel state information of the mobile terminal received from the interface; a control unit, clustering each base station dynamically according to the channel state information of the mobile terminal stored in the memory unit.

Abstract: A wireless communication method uses first and second demodulation reference signals in channel estimation of data and control signals, respectively, in a wireless communication system including a base station and a terminal. The base station informs the terminal of N parameters of first to Nth parameters to determine signal sequences for the first demodulation reference signal with a control signal of a higher layer, and informs the terminal of one parameter to determine a signal sequence for the second demodulation reference signal. The terminal defines a signal sequence with the one parameter informed of as the second demodulation reference signal, demodulates and decodes a control signal of the lower layer using the defined second demodulation reference signal, and defines a signal sequence with one parameter of the first to the Nth parameters with a correctly decoded control signal of the lower layer as the first demodulation reference signal.

Abstract: To secure a constant level or more of radio communication quality for each user equipment performing radio communication with a base station apparatus, and to increase the number of user equipment which the base station apparatus can accommodate under a condition of assuring the radio communication quality. In a radio communication system where there exist a base station apparatus having multiple antennas and user equipment for performing radio communication with a first antenna group including one or more of the antennas, the first antenna group is made configurable for each user equipment individually, and addition/deletion of the antenna to/from the first antenna group is performed based on the communication quality of each user equipment so that the number of antennas within the first antenna group may be minimized within a range satisfying a required value of the communication quality between the base station apparatus ad the user equipment.

Abstract: A transmitting station having plural antennas includes: a control information calculation unit that calculates control information for use by plural receiving stations according to a multi-user MIMO data transmission scheme; a control information transmission parameter calculation unit that calculates a control information transmission parameter based on spatial channel related information; and a control information transmission signal creation unit that creates a control information transmission signal, using the control information transmission parameter and a pilot signal. A resource element mapping unit maps control information transmission signals onto corresponding resource elements for transmission. On the other hand, the receiving stations each include a control information acquisition unit that acquires plural pieces of control information signaled on the corresponding resource elements, acquire control information destined for each receiving station, and demodulate received signals.

Abstract: By a base station that is not limited to a cell concept, the system control cost is controlled and an area of high-communication-speed/high-communication-quality is expanded. There are provided fixed-cell support base-station devices 420 and 421 having functions of physical layer processing and higher layer processing according to the cell concept in the related art and an unfixed-area support base-station device 430 having a physical layer processing function that is not limited to the cell concept. The unfixed-cell support base-station device 430 performs physical layer signal processing for a terminal in a low throughput area and selects an arbitrary antenna group from antennas or antenna group linked to the fixed-cell support base stations 420 and 421, and the fixed-cell support base stations 420 and 421 transmit their own transmission signals and transmission signals directed to the terminal together.

Abstract: In the case where a base station other than of a distributed antenna system provides a time or frequency at which a transmitted power is low, an antenna group configuration unit estimates a communication area of a mobile station using an uplink reference signal that the mobile station transmits, calculates an inter-system interference power for the communication area of each mobile station based on a received power of the out-of-system base station that the each mobile station reports, calculates the inter-system interference power to each of antennas by averaging the inter-system interference powers that the multiple mobile stations report, and decides antennas that form an antenna group according to magnitudes of the calculated inter-system interference powers.

Abstract: A base station performs an association between frequency range and combinations of a plurality of base stations including an local base station to notify a terminal of the association. According to the notified association, the terminal, for each frequency, calculates quality of communication with one base station or quality of communication with the combination of the plurality of base stations. The base station and the control station determine the base station/the plurality of base stations that communicate with the terminal, the wireless resource and the transmission scheme, based on the result. Further, the base station selects whether to notify an entirety of or a part of the association to the terminal using positional information of the terminal. Since the association information that is unnecessary for the terminal is not communicated, it is possible to further lighten the load of control.

Abstract: In an environment in which a macro base station and a low transmission power base station exist, the ratio of the interference reduction time period of the macro base station is optimized, and the throughput of the low transmission power base station is improved, while minimizing a reduction in throughput. The macro base station causes a high interference to other base stations and one or a plurality of low power nodes (LPN) subjected to interference from the macro base station. The macro base station sets first and second data transmission time periods and then determines the ratio of the second time period and the pattern of the first time period and the second time period based on communication quality in the first time period and communication quality in the second time period of the macro base station and the LPN.

Abstract: The error correction capability for wireless communication carried out involving propagation path fluctuation in time and frequency selectivity can be improved. A soft decision likelihood value inputted to an error correction decoder is multiplied by a weight determined according to the distance between the data symbol and pilot symbol corresponding to the soft decision likelihood value. Namely, the soft decision bit likelihood value corresponding to the data symbol is weighted according to the distances in time or frequency between the pilot symbol and data symbol. The weight is made smaller when the distance in time or frequency is larger.

Abstract: A base station broadcasts a message saying that transmittable ranging codes are limited by antenna IDs to limit antennas and the ranging codes to be searched, thereby reducing a processing load of the search. In a cellular radio communication system in which a base station device is connected to plural antennas, and antenna IDs for identifying the antennas are transmitted from the respective antennas, the base station device broadcasts a message saying that a group of ranging codes transmittable by a terminal device is limited by the antenna IDs, the terminal device receives the message, identifies the antenna ID, selects the ranging code from the group of the ranging codes corresponding to the antenna ID, and transmits the selected ranging code.

Abstract: In the case where a base station other than of a distributed antenna system provides a time or frequency at which a transmitted power is low, an antenna group configuration unit estimates a communication area of a mobile station using an uplink reference signal that the mobile station transmits, calculates an inter-system interference power for the communication area of each mobile station based on a received power of the out-of-system base station that the each mobile station reports, calculates the inter-system interference power to each of antennas by averaging the inter-system interference powers that the multiple mobile stations report, and decides antennas that form an antenna group according to magnitudes of the calculated inter-system interference powers.

Abstract: A wireless communication equipment includes receive processing and transmit processing. The receive processing includes a Fourier transform unit that transforms all received signals to frequency region signals by Fourier transform. A demodulation unit demodulates the received signals from the Fourier-transformed frequency region signals. A random access detection unit that monitors signals in frequency regions of random access signals of the Fourier-transformed frequency region signals, and detects that the random access signals are received, by a change pattern of the signals in the frequency regions of random access signals in one transmission time interval.

Abstract: To secure a constant level or more of radio communication quality for each user equipment performing radio communication with a base station apparatus, and to increase the number of user equipment which the base station apparatus can accommodate under a condition of assuring the radio communication quality. In a radio communication system where there exist a base station apparatus having multiple antennas and user equipment for performing radio communication with a first antenna group including one or more of the antennas, the first antenna group is made configurable for each user equipment individually, and addition/deletion of the antenna to/from the first antenna group is performed based on the communication quality of each user equipment so that the number of antennas within the first antenna group may be minimized within a range satisfying a required value of the communication quality between the base station apparatus ad the user equipment.

Abstract: Disclosed is a distributed antenna system that selects an antenna in accordance with the position of a mobile terminal and reduces the variation in the total number of mobile terminals using each antenna while maintaining adequate communication quality. In the distributed antenna system in which a large number of antennas are distributively disposed, an antenna group including antennas having good communication quality is selected in accordance with the position of a mobile terminal. Further, in accordance with the communication quality and load status of a current antenna group and with the communication quality and load status of a post-change antenna group, which is obtained by changing some antennas in the current antenna group, the post-change antenna group is formed by changing some antennas in the current antenna group with which a mobile terminal using a heavily loaded antenna communicates.