Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Nobuyoshi Horie

Shigeaki Suzuki

Yukimasa Sugino

Fumihiro Hasegawa

Shigenori Tani

Hiroyasu Sano

Yushi Naito

Hideaki Ebisawa

Yoshihisa Kagawa

Tomoko Ishii

A wireless communication device includes a transmission processing unit communicable with each of multiple communication peer devices through switching between beam directions in a time division manner, and a control unit that allows beam information representing how beams are used by the multiple communication peer devices with which the transmission processing unit is communicable to be shared by the multiple communication peer devices.

Wireless communication device, wireless communication system, control circuit, storage medium, and wireless communication method

A voice transmission device has a tandem pass through function in an STM, ATM, IP network, and a noise canceller () is provided at a latter stage of an echo canceller () in a coding part, and in a case where a multistage connection state does not occur, noise removal is performed to carry out efficient coding, and in a case where a relay is performed in the multistage connection state, switching is performed to stop the operation of the noise canceller (), and voice deterioration by redundant decoding and coding is prevented, and therefore, even in a cellular phone having no noise cancel function, or the like, and at both a normal time and a time of a tandem pass through state, high quality voice transmission can be performed, and further, since an unvoiced portion in voice data is increased by removing a noise component, a portion subjected to coding becomes small, and transmission amount of the line is reduced.

Voice transmission device and voice transmission system

Channel check test system

A facsimile signal transmission system which satisfies the stipulation of the signal sending time and the stipulation of the signal time interval for enabling successful facsimile communication even if a detection delay or a sending delay occurs. In a facsimile signal transmission system for transmitting a digital command signal (DCS signal), an echo protect tone signal (EPT signal), a training signal, and a training check signal, if an IDLE message signal output from a transmission part at the end of the DCS signal is received in a reception party, a first timer operated for a first predetermined time is started. When the first predetermined time has elapsed, sending of the EPT signal to the reception facsimile terminal is started. A second timer operated for a second predetermined time is started at the same time as sending of the EPT signal is started. When the second predetermined time has elapsed, sending of the EPT signal is terminated. A third timer operated for a third predetermined time is started at the same time as sending of the EPT signal is terminated. When the third predetermined time has elapsed, sending of the training signal to the reception facsimile terminal is started.

Facsimile signal transmission system

When there is an error in setting of a companding law of an encoder or a decoder, there is a problem of an error in judgment although it should be originally judged that the continuity of the testing channel does not exist. Therefore, a channel check test system includes a transmitting side DCME for inserting a nonlinear quantized input test pattern into a channel to be tested, and a receiving side DCME. The receiving side DCME includes an adder for adding an offset value to an output value of a linear converting section, a sign extracting section for extracting a sign from an output signal of the adder, a delay unit for delaying the extracted sign, an exclusive OR arithmetic unit for performing an exclusive OR operation of the extracted sign and an output signal of the delay unit, a counter for counting the number of times of conformity in which an output value of the exclusive OR arithmetic unit is in conformity with a predetermined value, and a comparator for comparing a counted value of the counter and a threshold value and outputting judged results. Existence or nonexistence of the continuity of the channel to be tested can be checked including an error in setting of the PCM companding law in one of the transmitting side DCME and the receiving side DCME.

When a frame detection signal is received which indicates that frame data was discarded during transmission, a facsimile signal corresponding to the oldest one of facsimile signals stored in a restored data storage part,is output to a modem

Equipment and method for transmitting facsimile signal

A reset signal generating part outputs reset signals RV and RD to a signal discriminating part, based on an output from a 2100 Hz detecting part which detects whether or not a tone of 2100 Hz exists in an input signal. When the 2100 Hz tone is detected, the signal discriminating part firstly resets a discrimination state at 'speech' and secondly sets the discrimination state at 'data' based on the reset signal. Therefore, a signal discrimination apparatus, wherein it is possible to reset the discrimination state at 'speech' at the beginning of a facsimile call even when no call control information is received, can be provided.

Signal discrimination apparatus, a method for discriminating a signal,

A counter increments a count value every given time period. An adaptive operation control unit selects channels in which adaptive operations are done from all the channels in obedience to the count value to output produced selection signals to AND circuits. Double-talk detection circuits judge the presence/absence of a double-talk state and output detection signals to the AND circuits. The AND circuits operate logical AND of the selection signals and the detection signals and output the logical AND results as control signals to filter coefficient updating circuits. The filter coefficient updating circuits update or do not update filter coefficients stored in FIR filter units according to the control signals. The FIR filter units produce echo replicas by calculating convolutions of the filter coefficients and the receive signals. Subtractors subtract the echo replicas from transmission signals to output residual signals.

Growing community of inventors

Tokyo, Japan

Nobuyoshi Horie