Abstract: A semiconductor device includes a semiconductor layer including an electron transit layer and an electron supply layer; a gate electrode, a source electrode and a drain electrode, the gate electrode, the source electrode and the drain electrode being disposed on the semiconductor layer; and a metal film connected to the gate electrode, wherein the semiconductor layer includes an active region, and an inactive region surrounding the active region in plan view, wherein the gate electrode includes, in plan view, a first region overlapping the active region, and two second regions having the first region interposed therebetween, the two second regions both overlapping the inactive region, and wherein the metal film contacts the two second regions.

Abstract: An optical module including: a photonic integrated chip in which an optical circuit is formed; an electronic integrated chip that drives the photonic integrated chip; and an interposer that electrically couples the photonic integrated chip and the electronic integrated chip, wherein the photonic integrated chip is arranged on a side of a first main surface of the interposer, and the electronic integrated chip is arranged on a side of a second main surface on an opposite side of the first main surface, and the interposer includes a power supply layer, a first power supply via coupled to the power supply layer and configured to supply a first power supply voltage to the photonic integrated chip, and a second power supply via coupled to the power supply layer and configured to supply a second power supply voltage to the electronic integrated chip.

Abstract: 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.

Abstract: A delay locked loop circuit includes a first delay circuit that includes a plurality of first delay devices and a plurality of second delay devices, the plurality of first delay devices and the plurality of second delay devices are coupled in series with each other, a second delay circuit that includes a plurality of third delay devices equal in number and identical in configuration to the plurality of second delay devices, the plurality of third delay devices are coupled in series with each other, a phase comparator that outputs a phase difference between a first delayed clock output from the first delay circuit and a second delayed clock output from the second delay circuit, a first control circuit that outputs a first control signal that controls a time, and a second control circuit that outputs a second control signal.

Abstract: A pulse position modulation circuit includes a delay path that includes a plurality of delay devices coupled in series with each other, a clock being passed through the plurality of delay devices, and a switching circuit that changes a time by which the clock is delayed in each of the plurality of delay devices according to input data.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A radio communication apparatus includes a baseband signal generator to generate digital data; a clock generator to generate 2N pulse signals corresponding to the digital data; a selector to select one of the 2N pulse signals; and a short pulse generator to reduce a pulse width of the signal selected by the selector, wherein the 2N pulse signals include a whole-period non-transmission pulse, a whole-period transmission pulse, and 2N-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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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?k?N being satisfied; and transmitting the pulse signals.

Abstract: 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.