Abstract: A phase correcting apparatus, for a radio transmitter which obtains a first radio signal (RS1) based on a first baseband signal (BB1), includes a demodulator which demodulates a feedback signal from which a part of RS1 is extracted by a first carrier signal (CS1) and which generates a second baseband signal (BB2), a modulator which modulates a difference signal between BB1 and BB2 by a second carrier signal (CS2) and which outputs a second radio signal (RS2), a power amplifier which amplifies RS2 to obtain RS1, a detector which detects a phase difference between BB1 and BB2, and a phase rotator which rotates any phase of BB1, BB2, CS1, or CS2 as a target phase correction amount, wherein the detector converts a desired analog signal obtained by multiplying BB1 and BB2 into a digital signal, and which detects the phase difference based on digital data.

Abstract: A calculating apparatus includes a first state variable calculating unit that calculates first state variables respectively having a memory effect and being of an amplifier that causes signal distortion; an amplifier model unit that based on the calculated first state variables, calculates the signal distortion caused by the amplifier, as a distortion characteristic; and an output unit that outputs the calculated distortion characteristic.

Abstract: A light-emitting module of the present invention comprises: a light source in which an LED element is disposed on a substrate and electrodes electrically connected to the LED element are provided on the substrate; a metal plate on which the light source is disposed; lead wires connected to the electrodes directly or via other electrode pattern; and a housing made of resin fixed onto the metal plate and housing the light source therein. Moreover, the housing includes a hole opening above the light source, and includes at least one pair of protrusions that protrude facing one another inside the hole and apply a bias to the light source to press the light source onto a metal plate side.

Abstract: A Doherty amplifier is provided with a clipping circuit for making signal power flow to ground if the signal power becomes equal to or higher than a predetermine value in order to prevent a carrier amplifier, which is a small amplifier, from being destroyed if the signal power is increased to a sevenfold to tenfold multiple of a ratio of the size of the carrier amplifier to that of a peak amplifier.

Abstract: A calculating apparatus includes a first state variable calculating unit that calculates first state variables respectively having a memory effect and being of an amplifier that causes signal distortion; an amplifier model unit that based on the calculated first state variables, calculates the signal distortion caused by the amplifier, as a distortion characteristic; and an output unit that outputs the calculated distortion characteristic.

Abstract: A planar light-emitting device includes an elongate first lightguide plate (13) having a light entrance end surface (13a) disposed facing an exit surface (12a) of a light-emitting package (12), a reflecting side surface (13b) extending substantially at right angles to the light entrance end surface to reflect light entering through the light entrance end surface, and a light exit side surface (13c) facing the reflecting side surface, and a flat plate-shaped second lightguide plate (14) having a light entrance side edge surface (14a) facing the light exit side surface (13c). The first lightguide plate is configured to satisfy the condition of t1<t2?t3, where: t1, t2 and t3 are the respective heights of the light exit side surface (13c), the reflecting side surface (13b) and the light entrance end surface (13a). The surfaces of the first lightguide plate other than the light entrance end surface (13a) and the light exit side surface (13c) are reflecting surfaces.

Abstract: A phase correcting apparatus, for a radio transmitter which obtains a first radio signal (RS1) based on a first baseband signal (BB1), includes a demodulator which demodulates a feedback signal from which a part of RS1 is extracted by a first carrier signal (CS1) and which generates a second baseband signal (BB2), a modulator which modulates a difference signal between BB1 and BB2 by a second carrier signal (CS2) and which outputs a second radio signal (RS2), a power amplifier which amplifies RS2 to obtain RS1, a detector which detects a phase difference between BB1 and BB2, and a phase rotator which rotates any phase of BB1, BB2, CS1, or CS2 as a target phase correction amount, wherein the detector converts a desired analog signal obtained by multiplying BB1 and BB2 into a digital signal, and which detects the phase difference based on digital data.

Abstract: A Doherty amplifier is provided with a clipping circuit for making signal power flow to ground if the signal power becomes equal to or higher than a predetermine value in order to prevent a carrier amplifier, which is a small amplifier, from being destroyed if the signal power is increased to a sevenfold to tenfold multiple of a ratio of the size of the carrier amplifier to that of a peak amplifier.

Abstract: A communication system in which circuits for generating transmitting-end synchronizing signals and receiving-end synchronizing signals can be realized easily even in the case of a data transmission rate being high and in which power consumption is low. A transmitting-end synchronizing signal selector in a transmitter selects one of a plurality of transmitting-end synchronizing signals with different phases outputted from a transmitting-end synchronizing signal generator on the basis of code-spread data to be transmitted. A transmitting-end signal output unit outputs a radio signal in synchronization with the selected transmitting-end synchronizing signal. A receiving-end synchronizing signal selector in a receiver selects one of a plurality of receiving-end synchronizing signals which are outputted from a receiving-end synchronizing signal generator and which are the same as the plurality of transmitting-end synchronizing signals on the basis of a despreading code.

Abstract: A light-emitting package allowing light to enter a thin lightguide plate efficiently has a package substrate 11, light-emitting elements 2 mounted on the package substrate, a transparent resin part 12 sealing the light-emitting elements on the package substrate, a cut portion 12a formed in the transparent resin part in parallel to the package substrate so as to be able to receive a side edge surface of a lightguide plate, and a reflecting layer 13 formed on the entire surface of the transparent resin part except the cut portion.

Abstract: A planar light-emitting device includes an elongate first lightguide plate (13) having a light entrance end surface (13a) disposed facing an exit surface (12a) of a light-emitting package (12), a reflecting side surface (13b) extending substantially at right angles to the light entrance end surface to reflect light entering through the light entrance end surface, and a light exit side surface (13c) facing the reflecting side surface, and a flat plate-shaped second lightguide plate (14) having a light entrance side edge surface (14a) facing the light exit side surface (13c). The first lightguide plate is configured to satisfy the condition of t1<t2?t3, where: t1, t2 and t3 are the respective heights of the light exit side surface (13c), the reflecting side surface (13b) and the light entrance end surface (13a). The surfaces of the first lightguide plate other than the light entrance end surface (13a) and the light exit side surface (13c) are reflecting surfaces.

Abstract: A mixer circuit contains a first terminal and a second terminal to which a first differential input signal is applied, and an active element switching a short-circuit between the first terminal and the second terminal. By driving the active element by a second differential input signal having a predetermined frequency, the first terminal and the second terminal are intermittently short-circuited at twice the frequency of a predetermined frequency.

Abstract: A mixer circuit contains a first terminal and a second terminal to which a first differential input signal is applied, and an active element switching a short-circuit between the first terminal and the second terminal. By driving the active element by a second differential input signal having a predetermined frequency, the first terminal and the second terminal are intermittently short-circuited at twice the frequency of a predetermined frequency.

Abstract: A communication system in which circuits for generating transmitting-end synchronizing signals and receiving-end synchronizing signals can be realized easily even in the case of a data transmission rate being high and in which power consumption is low. A transmitting-end synchronizing signal selector in a transmitter selects one of a plurality of transmitting-end synchronizing signals with different phases outputted from a transmitting-end synchronizing signal generator on the basis of code-spread data to be transmitted. A transmitting-end signal output unit outputs a radio signal in synchronization with the selected transmitting-end synchronizing signal. A receiving-end synchronizing signal selector in a receiver selects one of a plurality of receiving-end synchronizing signals which are outputted from a receiving-end synchronizing signal generator and which are the same as the plurality of transmitting-end synchronizing signals on the basis of a despreading code.

Abstract: A mixer circuit contains a first terminal and a second terminal to which a first differential input signal is applied, and an active element switching a short-circuit between the first terminal and the second terminal. By driving the active element by a second differential input signal having a predetermined frequency, the first terminal and the second terminal are intermittently short-circuited at twice the frequency of a predetermined frequency.

Abstract: A resistor is inserted in series with an inductor feeding a bias current and that reactance of an input matching circuit or of an output matching circuit is varied depending on variations of input signal power. The input impedance of the amplifying element is restrained from lowering even when the input signal power has increased so that a constantly satisfactory impedance matching is achieved irrespective of the input signal powers variations. Furthermore, restriction on increase of the bias current enables a limitation to be imposed on increase of the power consumption of the microwave amplifier.

Abstract: The present invention is characterized in that a resistor is inserted in series with an inductor feeding a bias current and that reactance of an input matching circuit or of an output matching circuit is varied depending on variations of input signal power. According to the present invention, the input impedance of the amplifying element is restrained from lowering even when the input signal power has increased so that a constantly satisfactory impedance matching is achieved irrespective of the input signal power variations. Furthermore, restriction on increase of the bias current enables a limitation to be imposed on increase of the power consumption of the microwave amplifier.

Abstract: An apparatus for correcting signals includes a unit for estimating distortion characteristics in high-frequency circuit portion which estimates distortion characteristics of a high-frequency circuit portion concerning amplitude distortion or phase distortion impairing linearity. The apparatus further includes an input signal processor for applying an amplitude distortion correcting function or phase distortion concerning function, which is calculated on the basis of the result of estimating the distortion characteristics, to an input signal such as low-pass signals.

Abstract: A data communication system for executing data transmission and reception by modulating data using a code according to a CDMA system, in the field of optical communication, includes a code modulator for generating a first modulation code such as a spreading code on the basis of a transmission clock which has a transmission speed higher than a bit rate of a bit clock of data, and multiplying each bit of the data by the first modulation code so as to generate a code-modulated signal. The data communication system further includes a clock extractor for extracting a reception clock, which has a transmission speed corresponding to the bit rate of the bit clock, from the received code-modulated signal.