Fujitsu Corporation

Yasuhiro Nakasha

Hiroki Hayashi

Takumi Itoh

Yoichi Kawano

Tatsuya Hirose

Takeshi Hoshida

Tomoyuki Akiyama

Shinsuke Tanaka

Yuu Watanabe

An optical communication element includes a plurality of slabs, an input port group, an output port group, a first waveguide group, and a second waveguide group. The plurality of slabs includes third waveguide. Each of the plurality of slabs include a predetermined number of first ports being arranged at an inlet the third waveguide at equal intervals in a lateral direction perpendicular to a light traveling direction, and input the optical signals, and a predetermined number of second ports being arranged at an outlet of the third waveguide at the equal intervals in the lateral direction so as to face the first ports, and output the optical signals. Each of the third waveguides are configured with a dimension that allows light intensity to be distributed at all traveling positions located in the lateral direction.

Optical communication element and optical neural network

A pulse position modulation scheme impulse radio transmitter includes: a bipolar return-to-zero type short-pulse generator; a bandpass filter that has a predetermined pass frequency band and which allows an output of the bipolar return-to-zero type short-pulse generator to pass; a transmission amplifier that amplifies an output of the bandpass filter; and a transmission antenna, wherein the bipolar return-to-zero type short-pulse generator includes: a trigger flip-flop with a position modulation function that outputs a pulse-width-variable pulse in each period of a clock signal, the pulse-width-variable pulse being inverted in each period of the clock signal and the pulse width of the pulse-width-variable pulse differing in accordance with transmission data; and a pulse generation filter that generates a positive pulse or a negative pulse in accordance with a direction in which a varying edge of the pulse-width-variable pulse changes.

Pulse position modulation scheme impulse radio transmitter and radio communication system

A radio communication apparatus for generating a pulse signal corresponding to a data signal, amplifying the generated pulse signal, and transmitting the amplified pulse signal as a radio signal, the apparatus including: a reference pulse signal generation unit which generates a reference pulse signal of opposite phase to the pulse signal and amplifies the reference pulse signal; and a combining unit which combines the amplified pulse signal and the amplified reference pulse signal, wherein a combined pulse signal output from the combining unit is transmitted as the radio signal.

Radio communication apparatus and pulse signal transmission method in radio communication apparatus

A communication apparatus includes: a pulse generation unit configured to alternately generate a positive pulse and a negative pulse indicating presence or absence of a pulse in accordance with a value of a data signal; a band-pass filter configured to filter the pulse generated by the pulse generator; and a transmission amplifier configured to amplify a signal filtered by the band-pass filter, and to output the signal as a transmission signal.

Communication apparatus

A communication device includes: a converting part converting a data signal from a non-return-to-zero signal to a return-to-zero signal; a trigger flip-flop inverting an output signal every time the return-to-zero signal changes in one cycle; a first filter outputting a positive pulse and a negative pulse alternately, which indicate existence and absence of the pulse corresponding to a value of the data signal, by removing a low frequency component of an output signal of the trigger flip-flop.

Pulse converting and shaping communication device

A transmission and reception apparatus includes: a transmitter circuit to transmit to an object a transmission signal including a comb-shaped wave in which a first plurality of pulses are arranged in a comb shape; and a receiver circuit to receive a reflection signal based on the transmission signal.

Imaging apparatus, and transmission and reception apparatus

A communication device includes an oscillator to generate an oscillation signal; a harmonic generator to generate a higher harmonic wave from the oscillation signal; a first filter to take out a first high frequency signal; a second filter to take out a second high frequency signal; a down conversion mixer to use the second high frequency signal to perform down conversion of a signal obtained by receiving a reflected signal of the first high frequency signal; a hybrid coupler to generate a first intermediate frequency signal and a second intermediate frequency signal, which are orthogonal with each other; a first mixer to take out a first baseband signal by mixing an output from the down conversion mixer with the first intermediate frequency signal; and a second mixer to take out a second baseband signal by mixing an output from the down conversion mixer with the first intermediate frequency signal.

Communication device and imaging apparatus

A radio communication apparatus includes a baseband signal generator to generate digital data; a clock generator to generate 2pulse signals corresponding to the digital data; a selector to select one of the 2pulse signals; and a short pulse generator to reduce a pulse width of the signal selected by the selector, wherein the 2pulse signals include a whole-period non-transmission pulse, a whole-period transmission pulse, and 2-2 partial-period transmission pulses, when the partial-period transmission pulse is selected, a band pass filter outputs a signal that lasts for part of a period having a 1-symbol length, when the whole-period non-transmission pulse is selected, the band pass filter outputs a signal attenuated by offsetting signals corresponding to the whole-period non-transmission pulse, and when the whole-period transmission pulse is selected, the band pass filter outputs a signal that lasts for a whole of the period having the 1-symbol length.

Radio communication apparatus

An impulse radio communication device includes a short pulse generator configured to change a shape of an impulse to be output; a bandpass filter configured to receive the impulse and output the impulse as a wave packet; an amplifier configured to amplify an output from the bandpass filter; and an antenna configured to output the wave packet, output from the amplifier, as a wireless signal, the short pulse generator includes a control section configured to change the shape of the impulse to be output, in response to an environmental condition of a transmission path for wireless communication.

Impulse radio communication device

A transmission device including a pulse generating section configured to generate a plurality of pulses using a signal of data and a signal obtained by delaying the signal of data, and to adjust the pulse width such that each of the plurality of pulses has a pulse width conforming to a sequence of the data; a band-pass filter filtering the plurality of pulses; and a transmission amplifier amplifying the filtered plurality of pulses and outputting the filtered plurality of pulses as a transmission signal.

Transmission device

A radio transmission apparatus has a first duty adjustment circuit which changes a duty ratio of a clock signal, a second duty adjustment circuit which changes the duty ratio of the clock signal to a duty ratio different from the duty ratio of the clock signal changed by the first duty adjustment circuit, a first AND circuit which takes a logical product between a data signal and the clock signal having passed through the first duty adjustment circuit, and a second AND circuit which takes a logical product between an output signal of the first AND circuit and the clock signal having passed through inversion of the output of the second duty adjustment circuit to generate a pulse signal.

Pulse radio transmission apparatus and transceiver

A pulse transmission method for transmitting data by using pulse signals, each having a predetermined pulse width; defining a symbol time at least N times the predetermined pulse width, N being at least 2; defining a basic delay time calculated by dividing the predetermined pulse width by a predetermined integer; placing the pulse signals in the symbol time by delaying the pulse signals by an integral multiple of the basic delay time from start of the symbol time, the number of the pulse signals being k and 0&#x2266;k&#x2266;N being satisfied; and transmitting the pulse signals.

Pulse transmission method, pulse transmission system, transmitter, and receiver

A transmitter circuit, which transmits data by using an impulse, has a variable delay circuit and a logic circuit. The variable delay circuit takes a clock as an input, and delays the clock in accordance with the data. The logic circuit takes the clock and an output of the variable delay circuit as inputs, and outputs an impulse by performing a logic operation between the clock and the output of the variable delay circuit.

Transmitter circuit and radio transmission apparatus for transmitting data via radio by using impulses

The impulse generator comprises a nonlinear transmission line capable of obtaining an impulse with a small half value width and a large amplitude, in which a plurality of transmission line units having a unit line unit and a diode are connected in series, a pulse generator connected to the transmission terminal of the nonlinear transmission line, and a bias-dependent element connected to the reception terminal of the nonlinear line, wherein the anode of the diode of the transmission line unit is connected to the transmission line and the cathode is connected to the ground, and one end of the bias-dependent element is connected to the reception terminal of the transmission line and the other end is biased to a negative potential.

Impulse generator utilizing nonlinear transmission line

A phase shifter circuit includes a plurality of first series circuits each comprised of a series connection of one capacitor and one resistor, a first circuit element including at least inductance connecting between a first end and a second end of a chain structure made by connecting the plurality of first series circuits in series, the first circuit element and the chain structure together constituting a first loop circuit, a plurality of second series circuits each comprised of a series connection of one capacitor and one resistor, a second circuit element including at least inductance connecting between a first end and a second end of a chain structure made by connecting the plurality of second series circuits in series, the second circuit element and the chain structure together constituting a second loop circuit, and a plurality of connection lines connecting between the first loop circuit and the second loop circuit.

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Kawasaki, Japan

Yasuhiro Nakasha