Abstract: A transmission circuit according to the present invention includes: an amplitude signal driving section (220) that generates a control voltage based on an amplitude signal in a high-output mode, and generates a control voltage at a predetermined level and a bias current based on the amplitude signal in a low-output mode; a variable gain adjustment section (114) that adjusts a power level of the phase signal; and a power amplifier (130) which amplitude-modulates the phase signal having the adjusted power level on the basis of the control voltage, in the high-output mode, and to a power supply terminal of which the control voltage is supplied and which amplitude-modulates the phase signal having the adjusted power level on the basis of the bias current, in the low-output mode.

Abstract: Provided is a multiband wireless apparatus that, even if the number of supported frequency bands increases, suppresses increase in the number of components, and completes cell search within a specified time. In a multiband wireless apparatus (1), a reception channel to which a current reception channel is going to be next switched is set in advance for one of a tunable duplexer (13) and a reception dedicated tunable filter (14) that is not connected to an antenna. An antenna switch (15), in a normal transmission/reception mode, connects the antenna to the tunable duplexer (13), and in a compressed mode, switches the connection of the antenna between the tunable duplexer (13) and the reception dedicated tunable filter (14).

Abstract: When switching the mode of a power amplifier between compressed mode and uncompressed mode, accurate transmission power control is realized. A transmission power control method includes setting a power setting value of mode to switch to, such that an inter-mode output power error is canceled (equal to step ST21), calculating an intra-mode output power error from the power setting value of the mode to switch to (equal to step ST23), calculating a gain linearity value based on the power setting value of the mode to switch to and an output power error of the intra-mode (equal to step ST24), and resetting the power setting value of the mode to switch to based on the gain linearity value (equal to steps ST25 and 26).

Abstract: Provided are a PLL modulation circuit, a radio transmission device, and a radio communication device capable of maintaining a modulation accuracy for modulation of a wide band.

Abstract: A current control circuit (5) recognizes whether or not a transmission signal is transmitted based on a control signal outputted from a transmission signal control circuit (4). When the transmission signal is transmitted, the current control circuit (5) controls a current flowing into a reception circuit (3) in accordance with control information representing any of at least two modes where the transmission signal is transmitted. When no transmission signal is transmitted, the current control circuit (5) controls the current flowing into the reception circuit (3) in accordance with control information representing a mode where no transmission signal is transmitted.

Abstract: A transmission circuit is capable of precisely compensating for an offset characteristic of an amplitude modulation section, and operating with low distortion and high efficiency over a wide output electric power range. A signal generation section outputs an amplitude signal and an angle modulation signal. An amplitude amplifying section inputs, to the amplitude modulation section, a signal corresponding to a magnitude of the amplitude signal having been inputted. The amplitude modulation section amplitude-modulates the angle modulation signal with the signal inputted from the amplitude amplifying section, and outputs a resultant signal as a modulation signal. The power measuring section measures an output power of the amplitude modulation section. An offset compensation section reads an offset compensation value from a memory in accordance with the output power of the amplitude modulation section, and adds the read offset compensation value to the amplitude signal.

Abstract: A transmission circuit precisely compensates for an offset characteristic of an amplitude modulation section and operates with low distortion and high efficiency over a wide output power range. A signal generation section outputs an amplitude signal and an angle-modulated signal. An amplitude amplifying section supplies, to the amplitude modulation section, a voltage corresponding to a magnitude of an inputted amplitude signal. The amplitude modulation section amplitude-modulates the angle-modulated signal by the voltage supplied from the amplitude amplifying section, thereby outputting a resultant signal as a modulation signal. A temperature measuring section measures a temperature of the amplitude modulation section.

Abstract: A three-dimensional optical waveguide is formed by laminating planar substrates such as a plurality of lens substrates and, an isolator substrate and a wavelength division multiplexing filter, the optical substrates at least include a waveguide substrate having a waveguide and a reflecting surface. In the three-dimensional optical waveguide, the planar substrates are positioned by markers integrally formed on at least two of the planar substrates. Light directed into the waveguide is reflected by a reflecting surface and passes through the lens substrates and the isolator substrate.

Abstract: Provided is a transmission circuit which is capable of compensating for an offset voltage and a sensitivity characteristic of a PA, and operating with low distortion and high efficiency. A regulator 18 supplies, to a PA 201, a voltage which is controlled in accordance with an amplitude signal to which a first offset value has been added. A regulator 19 supplies, to a PA 202, a voltage which is controlled in accordance with an amplitude signal to which a second offset value has been added. The PA 201 amplifies, in accordance with the voltage supplied from the regulator 18, a phase-modulated signal outputted from a phase modulator 13. The PA 202 amplifies, in accordance with the voltage supplied from the regulator 19, an output signal of the PA 201. A digital block 11 controls the first and second offset values in accordance with temperature information T measured by a temperature measuring section 21.

Abstract: Provided are a PLL modulation circuit, a radio transmission device, and a radio communication device capable of maintaining a modulation accuracy for modulation of a wide band.

Abstract: Provided is a polar modulation apparatus capable of performing power limit with a simple configuration even when controlling a transmission power and increasing the transmission signal output power control range. A polar modulation device (1) includes an amplitude limit unit (6) for limiting an amplitude component of an amplitude signal, a D/A converter (7) for converting an inputted digital signal into an analog signal, a power control unit (8) for performing power control so that the inputted signal is an output signal based on the power control signal, a voltage control circuit (9) for supplying voltage to an amplitude modulator (11) according to the output signal from the power control unit (8), an angle modulator (10) for performing angle modulation according to a phase signal, and an amplitude modulator (11) for performing amplitude modulation on the signal subjected to angle modulation, according to the voltage supplied from the voltage control circuit (9).

Abstract: A radio transmission apparatus according to the present invention detects an output current of a power supply section that varies in response to a variation of the output impedance of an amplification section, and corrects a distortion of the input/output characteristic of the amplification section by using an LUT corresponding to the detected output current. In addition, a threshold used for switching an LUT is caused to be different depending on a switching direction between LUTs, thereby suppressing frequent occurrence of switching of the LUT.

Abstract: A transmission modulation apparatus capable of dealing with characteristic variations of a high-frequency power amplifier without always forming an amplitude loop. Transmission modulation apparatus 100 is configured with level detector 140 that receives input of a level detection control signal and detects the output signal of high-frequency power amplifier 130, and offset voltage correcting section 150 that corrects an offset voltage using collinear approximation including a first point where the relationship between the power supply voltage value and the output voltage starts to shift from linear to non-linear based on an output signal of level detector 140 and a second point where output voltage is a minimum. Offset voltage correction is adaptively executed, and linearity between the voltage value of the baseband amplitude signal and the output voltage of high-frequency power amplifier 130 when the voltage value of the baseband amplitude signal is low is compensated.

Abstract: A compact transmission circuit for outputting a highly linear transmission signal regardless of the output power level and operating at a high efficiency is provided. A signal generation section 11 generates an amplitude signal and quadrature data based on input data. A calculation section 21 calculates using the amplitude signal and the quadrature data to output a discrete value having a level discrete at every predetermine time period, and first and second phase signals. An amplitude amplification section 17 outputs a voltage controlled in accordance with the discrete value. Angular modulation sections 13 and 14 angular-modulate the phase signals and output first and second angle-modulated signals. Amplitude modulation sections 15 and 16 amplitude-modulate the angle-modulated signals with the voltage from the amplitude amplification section 17 and output first and second modulated signals. A combining section 18 combines the first and second modulated signals and outputs a transmission signal.

Abstract: Provided is a frequency modulation circuit 1 for outputting a highly precise frequency-modulated signal regardless of variation in a characteristic of a VCO 15. A correction value calculation section 17 calculates a correction value Vt2 based on a voltage value (Vtx?Vt1) resulting from subtracting a control voltage Vt1, which is generated by a control voltage generation section 11, from a control voltage Vtx at which a sensitivity of the VCO 15 is maximized. A variable amplifier 18 amplifies the correction value Vt2. An addition section 13 outputs a control voltage Vt3, which results from adding the amplified correction value Vt2 to the control voltage Vt1, to the VCO 15 via a DAC 14.

Abstract: In a conventional optical device which mounts a semiconductor light emitting element, the processing is difficult and a manufacturing process cost is expensive because of the necessity of forming via holes in a substrate. An optical device comprises a laser diode which needs heat radiation, a glass substrate which is integrally molded into a mold glass for arranging the laser diode, a metallic heat sink arranged at an edge of the glass substrate for radiating heat generated from the laser diode, wherein an active layer proximity surface of the laser diode is arranged to oppose the heat sink, both of them are connected with a conductive paste through a lateral groove formed in the glass substrate.

Abstract: Provided is a transmission circuit that is capable of switching a bias circuit without allowing a power amplifier to enter a non-bias state. A first bias circuit 24 supplies a first bias signal to a power amplifier 17. A second bias circuit 25 supplies a second bias signal to the power amplifier 17. A first delay circuit 22 delays switching of an operation of the first bias circuit 24 for a first delay time. A second delay circuit 23 delays switching of an operation of the second bias circuit 25 for a second delay time. The first bias circuit 24 and the second bias circuit 25 are both simultaneously operated for a predefined time period, in order to prevent a transistor for amplification 171 from entering a non-bias state when switching an operation mode of the power amplifier 17.

Abstract: A three-dimensional optical waveguide is formed by laminating planar substrates such as a plurality of lens substrates and, an isolator substrate and a wavelength division multiplexing filter, the optical substrates at least include a waveguide substrate having a waveguide and a reflecting surface. In the three-dimensional optical waveguide, the planar substrates are positioned by markers integrally formed on at least two of the planar substrates. Light directed into the waveguide is reflected by a reflecting surface and passes through the lens substrates and the isolator substrate.

Abstract: A transmission circuit is provided which can quickly and accurately control an output power of a transmission signal even when the transmission signal is output at a high modulation rate and in a wide dynamic range. A switching control section controls a modulation method changing section to change a modulation method of a modulated signal generating section to a modulation method having a narrow dynamic range before controlling a switching section to switch amplification sections. An output adjustment control section controls output adjusting sections so that a difference in level between a transmission signal which is smoothed by a smoothing circuit and is before the amplification sections are switched, and a transmission signal which is after the amplification sections are switched, is caused to be smaller than a predetermined difference threshold value, when the modulated signal generating section operates in the modulation method having the narrow dynamic range.

Abstract: The polar modulation apparatus of the present invention can control the output power of a transmission signal over a wide range and compensate characteristic degradation reliably upon temperature change. Polar modulation transmission apparatus 100 is provided with: temperature sensor 120; temperature compensation section 1601 that corrects an amplitude signal and performs temperature compensation for transmission power amplification section 190; temperature compensation section 160-2 that corrects a power amplification signal and performs temperature compensation for power adjustment section 180; and correction value setting section 130 that sets correction values for temperature compensation section 160-1 and temperature compensation section 160-2, and, while only the amplitude signal is corrected according to a measurement result in temperature sensor 120 in the first mode, the amplitude signal and the power adjustment signal are corrected according to a measurement result in the second mode.