Panasonic Corporation

Matsushita Electric Industrial Co., Ltd.

Toshiyuki Wakisaka

Masahiro Maki

Mutsuhiko Oishi

Akihiro Yamashita

Fumio Ichihara

Tsunehiro Hanada

Yuji Igata

Hisao Koga

Tomohiro Kimura

Akio Kurobe

Masami Wada

Michinori Kishimoto

Shigeo Yoshida

Kazuaki Kusune

Nobutaka Kodama

Ryota Yukizane

Shoichi Koga

Shouichi Koga

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

A communication network system sets communication parameters which enable an operation under a maximum possible communication rate in a situation where a transmission path has cyclic noise/impedance fluctuations. A transmission/reception apparatustransmits training packets for checking the state of the power line at two distinct points in time. A transmission/reception apparatus analyzes SNR at each carrier frequency, and stores an SNR evaluation result. The transmission/reception apparatus compares two SNR evaluation results which are obtained through two instances of a channel estimation algorithm, selects an SNR evaluation result which dictates a faster PHY rate, and transmits it to the transmission/reception apparatus. The transmission/reception apparatus changes modulation/demodulation rules based on the received SNR analytical result.

Communication network system, and transmission/reception apparatus, method and integrated circuit for use therein

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

A communication network system sets communication parameters which enable an operation under a maximum possible communication rate in a situation where a transmission path has cyclic noise/impedance fluctuations. A transmission/reception apparatus transmits training packets for checking the state of the power line at two distinct points in time. A transmission/reception apparatus analyzes SNR at each carrier frequency, and stores an SNR evaluation result. The transmission/reception apparatus compares two SNR evaluations results which are obtained through two instances of a channel estimation algorithm, selects an SNR evaluation result which dictates a faster PHY rate, and transmits it to the transmission/reception apparatus. The transmission/reception apparatus changes modulation/demodulation rules based on the received SNR analytical result.

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 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

A card device to be inserted into a slot of an electronic apparatus having an electronic apparatus ground and electrically connected to this electronic apparatus, including a single antenna provided on a carrier, a card ground which is disposed on the carrier and electrically connected to the antenna, and a switch for carrying out, at a high frequency, a connection/disconnection of the card ground to/from the electronic apparatus ground in a condition where this card device is inserted in the slot.

Card device, electronic apparatus, and wireless device

An antenna diversity communications device switches communications paths between a plurality of antennas to improve reception in a frequency diversity communications system. Antenna selection is done in response to measurement of the receiving condition of the selected antenna. A memory unit stores frequency difference information between the current channel and the next channel. When the frequency difference between the current channel and the next channel is small enough to predict good correlation between the channels, and if current receiving conditions are good, the current channel remains connected. When the frequency difference between the current channel and the next channel is large enough to predict poor correlation, or if the receiving conditions on the current channel are bad, one of the other channels is selected.

Growing community of inventors

Iizuka, Japan

Toshiyuki Wakisaka