Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Yasuo Hamamoto

Akihiro Takeuchi

Masazumi Yamada

Akira Iketani

Kenji Morimoto

Atsuo Ochi

Tadashi Kunihira

Yoshitaka Ohta

Masaaki Kobayashi

Chiyoko Matsumi

Hironori Nakae

Hidetoshi Takeda

Yosuke Ukita

Yoichi Yamamoto

Mutsuyuki Okayama

Taisaku Suzuki

Mami Takahashi

Shuichi Sato

Haruo Ohta

Hiroshi Hayashino

Hiroshi Saito

Yoshifumi Yanagawa

Masayuki Yoneyama

Hideaki Mita

Makoto Goto

Yukio Kurano

Kazuhiro Wake

Tatsuhiko Ikeda

Yuji Nadamoto

Yuzo Murakami

Kazuhiro Ohta

Katsufumi Kohno

Seiji Harada

Kenji Kunitake

A wireless slave device for performing wireless network communication with another wireless slave device, the other wireless slave device being connected to a terminal, and wired network communication with a terminal, the wireless slave device including a wireless reception unit that wirelessly receives a notification frame including a MAC address of the terminal connected to the other wireless slave device and a MAC address of the other wireless slave device, a storage unit that associates and stores the MAC address of the other wireless slave device and the MAC address of the terminal both included in the wirelessly received notification frame, a wire reception unit that receives a frame transmitted from the terminal connected to the wireless slave device, and a filtering unit that discards the frame if the transmission destination MAC address of the frame received by wire does not match the MAC address stored in the storage unit.

Wireless slave unit

A transmission device () outputs, to a reception device (), a stored amount of packets in a first transmission buffer () just before a certain packet has been written to the first transmission buffer. A first reception buffer amount read unit () in the reception device reads a stored amount of packets in a first reception buffer just before the certain packet has been read from the first reception buffer. A storage amount addition unit () adds the stored amount of packets in the first transmission buffer and the stored amount of packets in the first reception buffer, and a correction unit () adjusts the frequency of a variable frequency oscillator in a reception timestamp timerso that the resulting added value is a constant value.

Transmission device and reception device

A wireless receiver including receiving antennas, frequency-space transformers, noise wave removers, a back-end signal processor, a pattern detector, a broadcast interruption detector, and a back-end controller. The frequency-space transformers convert signals received by the antennas into frequency-space signals. The noise wave removers each at least perform the calculation of a transmission line coefficient matrix and the calculation of an inter-antenna covariance matrix on the frequency-space signals. A controller controls the back-end signal processor to operate when the multicarrier transmission waves have been detected to be interrupted. The noise wave removers each perform the calculation of the inter-antenna covariance matrix when a broadcast interruption detector has detected the interruption of the multicarrier airwaves. Thus, the wireless receiver removes noise generated within it, thereby having high reception sensitivity.

Wireless receiver

A demodulation device comprises at least a diversity combiner, an elimination parameter storage, an elimination parameter investigator, a noise eliminator, and a noise collection means. The elimination parameter storage stores elimination parameters used for eliminating a noise, as elimination parameters for each of antennas, the noise collection means receives a noise and outputs the received noise as a collected noise signal, and the diversity combiner outputs a combined signal along with combining parameters, each representing a parameter related to the combining for each of the antennas. The noise eliminator eliminates the noise by using the elimination parameters for all the antennas as well as the combining parameters for all the antennas.

Demodulation device

In a network including at least two transmission paths whose bands are respectively managed, an RTT test of DTCP-IP may fail due to a relay wait time generated by the band management regardless of retrials. An objective of the present invention is to assure success of the RTT test. A master unit device manages bands of the transmission paths and includes an RTT test detection section detecting a failure of the RTT test, and a band management section modifying a band management (TXOP allocation) schedule based on an RTT test failure detection. With this configuration, a time band during which no TXOP is allocated is provided between the transmission paths whose bands are respectively managed, thereby assuring success of the RTT test.

Master unit device and band management method used by the same master unit device

One transmission rate of a physical layer (PHY rate) is selected from among a plurality of PHY rates of a protocol stack by calculating one or more effective values of transmission rates of an upper layer of the protocol stack with respect to one or more PHY rates of the plurality of PHY rates respectively, and making a comparison with use of the calculated one or more effective values. Each of the one or more effective values is calculated based on (i) an ideal value of corresponding one of the transmission rates and (ii) a retransmission ratio via the physical layer that corresponds to a reception power value detected in the reception apparatus.

Transmission device, transmission method, system LSI, and program

A wireless communication apparatus is provided which is capable of performing synchronous transmission of a stream such as a video signal and therefore performing high-quality video transmission. The sending side generates time information based on a count of a beacon timer, adds the time information to a data packet of a video signal and sends the data packet. The receiving side, using PLL based on a timer count contained in a beacon, generates a clock having a higher frequency every time a beacon signal is received. The receiving side counts the clocks and accordingly generates new time information. This time information is compared with the time information added to the received data packet of the video signal, and the data packet is outputted only when the two match with each other.

Wireless communication apparatus

A data reception device having a reception data buffer unit storing a plurality of packets contained in a data packet, a reception data amount measuring unit measuring the data amount stored in the reception data buffer unit, a variable clock generation unit generating a clock having a variable frequency, a time information output unit outputting second time information counted in accordance with the frequency of the clock generated by the variable clock generation unit, and a first time information comparison unit comparing the first time information added to the packets with the second time information outputted from the time information output unit and controlling the timing of outputting the packet stored in the reception data buffer unit. The reception data amount measuring unit controlling the frequency of the clock generated by the variable clock generation unit in accordance with measured values obtained by the reception data amount measuring unit.

Data reception device

The present invention is built on a time out control apparatus to control the time out when a packet is transferred between terminal units connected to different buses. In the time out control apparatus, delay measuring means measures the delay time required for a response packet to be received after a request packet is sent to a terminal unit (control unit) connected via a bus. Delay information list generating means generates a delay information list in which the delay times measured by the delay measuring means are related to the individual identification information on the respective terminal units. Information output means reads out the delay time from the delay information list in accordance with a request from the terminal unit and outputs the delay time to the terminal unit. This sets the delay time on the time out register of the terminal unit.

Time-out control apparatus, terminal unit, time-out control system and time-out procedure

Data editing system for finally editing a recording medium using received compressed data

A transmission medium connecting device is used for connecting multiple bus type transmission media. The connecting device includes an apparatus information list containing information related to apparatuses connected to the bus type transmission media. The connecting device collects the apparatus information of each of the apparatuses, and prepares the apparatus information list. Also included are a packet receiver for receiving a packet transmitted from the transmission media and a packet transmitter for transmitting a packet to the transmission media. An apparatus connected to the bus type transmission media may request access to the apparatus information list and read out information from the apparatus information list regarding another apparatus to be communicated with.

Transmission medium connecting device, controlling device, controlled device, and storage medium

A serial bus control apparatus is disclosed. The apparatus includes a device for providing a reservation control table for reserving a transmission bandwidth and a transmission channel used at a future time on a serial bus. The reservation control table is organized such that transmission of data of certain bandwidth and channel at a certain future time can be reserved for a transmission between arbitrary nodes. The reservation control table is stored and controlled on a first register. The register is accessible for reading and writing from an arbitrary node on the serial bus. The apparatus may further include a detection part to detect present time and a second and third register for securing available transmission bandwidth and channel at present time. By having this reservation control table, it becomes possible for each node on the serial bus to secure transmission of data of certain bandwidth and transmission channel in a desired future time.

Reservation of transmission bandwidth and channel reservation for IEEE 1394 bus

A data recording/reproducing apparatus of the invention records data in a plurality of tracks on a tape like recording medium by using a head unit mounted on a rotational cylinder and reproduces recorded data from the tracks, the tracks having at least two azimuth angles different from one another, and the tracks of the different azimuth angles being alternately located on the recording medium, the apparatus including: a formatter for providing, to each of the tracks, a normal data region to be used in normal reproduction and at least one search data region to be used in reproduction at a standard variable reproduction speed; for grouping the plurality of tracks into track sets each having a predetermined number of tracks, each search data region being located in the same position on a corresponding track included in the track set, and for placing identical search data in the search data region of each track included in the track set.

Data recording/reproducing apparatus and method for high speed play

Growing community of inventors

Osaka, Japan

Yasuo Hamamoto