Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Tsunehiro Hanada

Akihiro Yamashita

Masahiro Maki

Mutsuhiko Oishi

Fumio Ichihara

Toshiyuki Wakisaka

Yuji Igata

Hisao Koga

Nobutaka Kodama

Ryota Yukizane

Hidekazu Matsunobu

Kazuaki Kusune

Masaharu Uchiyama

A first communication apparatustransmits a pilot signal which was generated by a pilot signal generation section, at predetermined timing, and detects an unbalance component of a transmission lineat the time of pilot signal transmission in an unbalance component detection section, and controls a transmission signal in such a manner that an unbalance component is reduced by a transmission control sectionon the basis of the detected unbalance component.

Line status detection apparatus, communication apparatus, and line status detection method

An electronic device capable of decreasing power consumption is provided. A multiple function apparatus including a power line communication function has a plurality of units such as a PLC board, a main control board, a printer control board, a printer, and a FAX control board. The multiple function apparatus also includes a device power supply unit for supplying power to the units independently. A power supply control unit of the PLC board outputs a power supply control signal in response to a state change of the multiple function apparatus and controls power supply to each unit.

Electronic device and image processing apparatus

A line state detecting apparatus provided in a balanced transmission system includes, in transmission lines comprising a pair of conductors WWconnected to a transmitting portioncurrent transformers TTprimary sides of which are inserted to respectives thereof in series therewith and secondary sides of which are connected in series to cancel currents or voltages of the two transformer by each other, and a detecting portionfor detecting currents or voltages on secondary sides of the current transformers TT. By an output of the detecting portiona difference of currents or voltages of the conductors WWof the transmission lines is provided and an unbalance component between the conductors WWis detected.

Line state detecting apparatus and transmitting apparatus and receiving apparatus of balanced transmission system

A balanced transmission signal Tx (t) (voltage e, &#x2212;e) is applied to a transmission line (L, L), a suppression signal (e) is generated from a common mode suppression signal source (e), and the suppression signal (e) is superposed on respectives of balanced transmission signals via adders (). By pertinently controlling a level of the suppression signal (e), voltage levels and phases of respectives of the transmission signals transmitted to the transmission lines (L, L) are controlled.

Balanced transmitting apparatus

A multicarrier communication method selects carriers on the basis of an SN-ratio and the balancing of a transmission line. Available carriers are selected in accordance with the balancing of the balanced transmission line, in which the balancing is measured at either a sending terminal or a receiving terminal or alternatively at both, and the SN-ratio is measured between the sending terminal and the receiving terminal. Additionally, a modulation method having the greatest permissible multivalue is selected for each of the carriers, wherein the carriers are selected in light of the SN-ratio and balancing, or alternatively in a highest-to-lowest order of frequency. Transmission power is controlled for each of the carriers to suppress radiated emission, and the SN-ratio and balancing are measured at predetermined time intervals to renew the selection of the carriers and the selection of the modulation methods.

Multicarrier communication method and system, and communication apparatus incorporated therein

It is an object of the invention to provide a communication apparatus, a communication system and a communication method enabling efficient transmission in accordance with a situation of a wired transmission line and capable of reducing an influence by a radiation power of the transmission line. The communication apparatus of the invention executes wired transmission using a plurality of sub carriers and includes a transmission signal generator for generating a transmission signal, and a transmission signal controller for controlling a transmission power of the transmission signal generated by the transmission signal generator based on a radiation power in a transmission line in correspondence with a frequency of the sub carrier, and a transmitter for transmitting the transmission signal the transmission power of which is controlled by the transmission signal controller via the transmission line.

Communication apparatus, communication system and communication method

A cable connecting device for power line communication includes: a first wiring lineand a second wiring linethrough which AC power is capable of being supplied; a power plugwhich is electrically connected to the first wiring lineand the second wiring lineand whose wiring lines are capable of being supplied with AC power; an Ethernet portthrough which a communication signal is capable of being input and output; a power line communication modemthat is connected to the Ethernet portand that is connected to the second wiring linethrough which a communication signal is transmitted by using AC power input to the power plugthrough the first wiring linebetween the power plugand the Ethernet porta filterdisposed on the first wiring lineand having high impedance in at least a frequency band used for power line communication rather than a frequency band used for AC power; and connectorstowhich axe electrically connected to the first wiring linebetween the filterand the power line communication modemand to which AC power from the first wiring lineis capable of being supplied.

Power line communication apparatus and connecting device

A radiation information management device comprises a measuring unit, a comparing unit, and a management information generating unit. The measuring unit measures unwanted radio wave radiation radiated from a balanced transmission line. The comparing unit compares a measured value of unwanted radio wave radiation, which the measuring unit has measured, with a reference value that is predetermined, and then notifies the comparison result to the management information generating unit. The management information generating unit refers the comparison result, generates the management information related to the unwanted radio wave radiation including information showing that the measured value is exceeded the reference value, then notifies to a first communication device and a second communication device. The first communication device and the second communication device take a measure to reduce transmitting power based on the management information regarding the unwanted radio wave radiation. Thus, in the first communication device and the second communication device, the unwanted radio wave radiation radiated from the balanced transmission line can be controlled within the reference value.

Growing community of inventors

Fukuoka, Japan

Tsunehiro Hanada