Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Akihiro Yamashita

Fumio Ichihara

Toshiyuki Wakisaka

Tsunehiro Hanada

Masahiro Maki

Mutsuhiko Oishi

Yuji Igata

Kazuaki Kusune

Hisao Koga

Nobutaka Kodama

Hiroyuki Matsuba

Hideaki Yamashita

Tomoyuki Noguchi

Masaharu Oyama

Ryota Yukizane

Hiroaki Nakashima

Shunichi Uchinami

Shinsuke Sato

Hirokazu Ikeda

Hidekazu Matsunobu

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

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

An electric power outlet apparatus for enabling electric machines containing a communication apparatus to be connected to indoor power wiring used for power-line carrier communications easily in an optimum state is provided. A tap partconnected to a power plugthrough a power cordincludes an impedance adjustment unitand power jacks, andand is housed in a tap casingschematically shown. The power jacksandare connected directly to the power cordand the power jacksandare connected to the power cordthrough the impedance adjustment unit. Color display parts, andfor indicating the connection state of the power jacks, andto the impedance adjustment unitare provided on the periphery of slots on the surface of the tap casing

Electric power outlet 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

Printed circuit board

A communication transformer for power line communication includes a magnetic core, a plurality of transfer-purpose windings wound on the magnetic core, and an additional winding. The additional winding is wound on the magnetic core in such a manner that the additional winding is positioned between the plurality of transfer-purpose windings, and does not contribute in signal transfer operations. The communication transformer is arranged such that a half way portion of the additional winding along a length direction thereof is electrically connected to a constant potential.

Communication transformer for power line communication

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.

Radiation information management device and communication device

A communication apparatus includes a transmission signal generation section, a transmission signal control section, a transmission section, a leakage electric power detection section, and an electric power control judgment sectionThe transmission signal generation sectiongenerates a transmission signal for carrying out transmission using a plurality of sub-carriers, under control of the transmission signal control section, and has a transmission electric power control function with respect to each sub-carrier. The leakage electric power detection sectiondetects electric power which is leaked from a transmission lineamong transmission electric power. The electric power control judgment sectionjudges necessity of transmission electric power control by the transmission signal control section, on the basis of a leakage electric power signal from the leakage electric power detection section, and in case that it was judged that transmission electric power control is necessary, it notifies that effect to the transmission signal control sectionThe transmission signal control sectioncontrols transmission electric power of a sub-carrier, on the basis of the leakage electric power signal from the leakage electric power detection section

Communication apparatus and communication method

In a display device arranging anode wires and cathode wires in a matrix shape, disposing light emitting elements at the intersections, scanning and driving the cathodes at specific time intervals, and driving the anode of a desired light emitting element in synchronism therewith, thereby selectively emitting the light emitting element, the display controller includes a setting unit for setting the discharge time for discharging the accumulated charge of the light emitting elements before light emitting of the light emitting elements, and operates and controls the anode controller and cathode controller for discharging the accumulated charge of the light emitting elements within the set discharge time, and also operates and controls the anode controller and cathode controller for emitting the light emitting elements after discharge control of the accumulated charge. In the display device having such configuration, supposing the luminance of the light emitting element when emitting light in no-charge or almost no-charge accumulated state to be Le, and the luminance by actual light emission to be Lp, they are in the relation of Lp&#x2267;0.9&#xd7;Le, and further supposing the discharge time to satisfy this relation to be Tx, the discharge time Rt of actual discharge is determined to satisfy the relation of Tx&#x2266;Rt.

Display device and driving method thereof

A driving method of a display device which includes cathodes formed by plural stripe-lines and anodes across the cathodes and formed by plural stripe-lines as well as a light-emitting layer provided between the cathodes and anodes. Firstly, illuminate a first light-emitting element connected to a first cathode, secondly, in order to illuminate a second light-emitting element connected to a second cathode, run electric current into the second element. In this case, remove part of stored charges in the second element and leave charges in at least one light-emitting element other than the second element, then run electric current into the second element. This driving method allows the display device to reduce the power consumption.

Driving method of a display device employing electro-light-emitting elements and the same display device

By increasing/deceasing electric energy per unit time supplied to heat energy generation means arranged in a liquid chamber having a nozzle, the amount of the ink emitted from the nozzle can be changed to correct a difference in dot diameter which occurs nozzle by nozzle and a change in dot diameter with time and to permit gradational printing.

Growing community of inventors

Miyaki-gun, Japan

Akihiro Yamashita