Tokyo, Japan
Tokyo, Japan

KDDI Corporation is a Japanese telecommunications operator formed in October 2000 through the merger of DDI Corp. , KDD Corp., and IDO Corp. It has its headquarters in the Garden Air Tower in Iidabashi, Chiyoda, Tokyo.KDDI provides mobile cellular services using the "au by KDDI" brand. ISP network and solution services are provided under the au one net brand, while "au Hikari" is the name under which long-distance and international voice and data communications services and Fiber to the Home services are marketed. ADSL broadband services carry the brand name "ADSL One", and IP telephony over copper is branded as "Metal Plus". Wikipedia.


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In a wireless communication system in which when connecting one terminal apparatus to a base station apparatus and another base station apparatus, the other base station apparatus selects a frequency band to be used for control channels transmitted from the terminal apparatus to the other base station apparatus from a plurality of frequency bands usable by the other base station apparatus, and notifies the terminal apparatus of the selected frequency band, the base station apparatus acquires from the terminal apparatus information about radio quality of a signal received from the other base station apparatus for at least one frequency band out of the plurality of frequency bands, extracts a portion of frequency bands out of the plurality of frequency bands based on the acquired information about radio quality, and notifies the other base station apparatus of information representing the portion of frequency bands.


A terminal device is configured to establish a communication link with communication equipment through a base station device such that, upon establishing the communication link, part of the communication link is left for a certain base station while another part of the communication link is established with the terminal device through the other base station device according to a plurality of architectures, wherein the terminal device includes a wireless communication part configured to transmit support architecture information representing an architecture supported by the terminal device among a plurality of architectures to the base station device.


In a wireless communication system in which when connecting one terminal apparatus to a base station apparatus and another base station apparatus, the other base station apparatus selects a frequency band to be used for control channels transmitted from the terminal apparatus to the other base station apparatus from a plurality of frequency bands usable by the other base station apparatus, and notifies the terminal apparatus of the selected frequency band, the base station apparatus acquires, from the terminal apparatus, information about radio quality of a signal received from the other base station apparatus for at least one frequency band out of the plurality of frequency bands, extracts portion of frequency bands out of the plurality of frequency bands based on the acquired information about radio quality, and notifies the other base station apparatus of information representing the portion of frequency bands.


In a communication network system connected between a transmission node and a reception node, both the transmission node and the reception node store the same secret information with their secret information storage units. The transmission node includes a counter configured to increase its transmission count value by 1 for transmitting each message, wherein a MAC generator generates MAC based on secret information, transmission data, and its transmission count value, thus transmitting a message including transmission data and MAC. The reception node includes a counter configured to increase a reception count value by 1 for receiving each message, wherein a MAC checking part generates MAC based on secret information, reception data, and its reception count value, obtained from the received message, thus checking whether the generated MAC matches the MAC obtained from the received message.


A video encoding apparatus that encodes a video having a plurality of color components includes: a linear prediction unit configured to perform linear prediction of reference pixels of a prediction target color component using reference pixels that are used in intra prediction for a color component other than the prediction target color component among the plurality of color components; and an intra prediction unit configured to perform intra prediction of a prediction target block of the prediction target color component using the reference pixels of the prediction target color component that have been obtained through the linear prediction performed by the linear prediction unit.


Patent
Denki Kogyo Co. and Kddi | Date: 2017-06-21

The apparatus automatically corrects deformation of directivity in a vertical plane caused by abnormality in transmission paths and receiving paths. The apparatus includes transmission system detection means (13-1 to 13-4) configured to individually detect abnormality occurring in each of the transmission paths, receiving system detection means (23-1 to 23-4) configured to individually detect abnormality occurring in each of the receiving paths, and control means (30, 40) configured, if any abnormal transmission path has been detected by the transmission system detection means (13-1 to 13-4), to correct deformation of directivity of the transmission antenna in a vertical plane caused due to abnormality in the transmission path by changing and setting a phase and an amplitude of the transmission signal passing through a normal transmission path, and if any abnormal receiving path has been detected by the receiving system detection means (23-1 to 23-4), to correct deformation of directivity of the receiving antenna in a vertical plane caused due to abnormality in the receiving path by changing and setting a phase and an amplitude of the receiving signal passing through a normal receiving path.


Patent
Kddi | Date: 2017-03-10

A base station system according to an aspect of the invention includes a baseband unit (BBU) and a radio frequency (RF) unit (RFU) connected to the BBU via a communication line. The RFU (BBU) measures the frequencies of occurrence of sampled values indicated by sampled data that is a digital signal corresponding to a baseband signal to be transmitted to the BBU (RFU), and generates a frequency distribution representing a relationship between the sampled value having occurred and the frequency of occurrence. Furthermore, the RFU (BBU) determines a plurality of thresholds for compressing the sampled data, which are used for quantization processing of the sampled value, in accordance with the generated frequency distribution, and compresses the sampled data by the quantization processing using the plurality of thresholds.


A control device configured to control communication between a terminal and a base station manages, concerning the communication, first information representing a part of a number corresponding to an order of a packet and held by each of the terminal and the base station and second information representing another part of the number corresponding to the order of the packet and transmitted from the terminal to the base station, determines whether the first information matches between the base station and the terminal, and controls the terminal to transmit a signal used to execute reconnection processing for resetting the number of the packet upon determining that the first information does not match between the base station and the terminal.


The number of reference pixels to be referenced in order to reduce redundancy among color components is to be reduced, while suppressing degradation in encoding performance. An intra prediction unit (20A) that performs intra-frame prediction includes an adaptive-sub-sampling luma reference pixel acquisition unit (21A) and an adaptive-sub-sampling chroma reference pixel acquisition unit (22A). In the case where an input image a is an image of a non-YUV420 format and the encoding unit is the smallest CU block, the adaptive-sub-sampling luma reference pixel acquisition unit (21A) sub-samples reference pixels existing neighboring a luma block corresponding to a chroma prediction target block based on a luma intra prediction mode, and acquires a pixel value of each of the sub-sampled reference pixels. In the case where the input image a is an image of a non-YUV420 format and the encoding unit is the smallest CU block, the adaptive-sub-sampling chroma reference pixel acquisition unit (22A) sub-samples reference pixels existing neighboring the chroma prediction target block based on the luma intra prediction mode, and acquires a pixel value of each of the sub-sampled reference pixels.


A communication apparatus performs communication in a manner such that communication with a first base station apparatus using a first frequency band and communication with a second base station apparatus using a second frequency band are switched on a per-subframe basis, obtains, from the first base station apparatus, specification information that specifies a subframe in which the first frequency band should be used and a subframe in which the second frequency band should be used among a plurality of subframes included in one or more frames, and performs control on the basis of the specification information to communicate with the first base station apparatus in the subframe in which the first frequency band should be used and with the second base station apparatus in the subframe in which the second frequency band should be used.

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