Abstract: An RF transmitter includes a modulating circuit adapted to modulating an RF signal, an output amplifier adapted to amplify the modulated RF signal; an auto tuner generating a tuning voltage that varies in accordance with operating temperature fluctuations and/or manufacturing process variances, and a reference current generating circuit adapted to generate a reference current in response to the tuning voltage.

Abstract: A signal scaling device (D), for a transmission path of a wireless communication equipment, comprises a processing means (PM) adapted to receive a phase and/or amplitude modulated signal (I/Q) to transmit, and arranged to multiply said phase and/or amplitude modulated signal with a chosen complex gain in order to output said phase and/or amplitude modulated signal with a chosen scaled amplitude and a chosen phase offset.

Abstract: A circuit for de-emphasizing information transmitted via a differential communication link includes a voltage mode differential circuit and a bi-directional current source circuit. The voltage mode differential circuit includes a first and second output terminal. The voltage mode differential circuit provides a first voltage via the first output terminal and second voltage via the second output terminal in response to a differential input voltage. The bi-directional current source circuit is operatively coupled between the first and second terminals. The bi-directional current source circuit selectively provides current in a first and second direction between the first and second terminals based on the first and second voltage.

Abstract: An optical sender is disclosed that operates in a Differential Quadrature Phase Shift Keying modulation scheme for high speed optical transmission and is capable of performing logical calculations at a low speed. The optical sender transmits a Differential Quadrature Phase Shift Keying (DQPSK) signal generated with modulation signals ?k and ?k so that a signal directly output from a signal receiver corresponding to the optical sender is in agreement with data signals Ik and Qk to be transmitted. The signal receiver is capable of modulation by DQPSK, and the modulation signals ?k and ?k are precoded by using the data signals Ik and Qk and the modulation signals one symbol earlier (?k?1 and ?k?1) . The optical sender includes plural precoders that perform logical calculation simultaneously and in parallel on plural data signals one period after another period.

Abstract: A method and apparatus for data transmission are provided. Data values of a plurality of channels are transformed into a transmission signal. An enhanced shaping filter is provided to shape a binary stream of only single digits and generate a shaped signal. A weighting unit is coupled to the output of the shaping filter, weighting the shaped signal to effectively generate a quality baseband signal. The binary stream is converted from the data values through spreading and scrambling. A scrambling unit, scrambles the binary stream with scrambling codes. A spreading unit spreads the binary stream at a chip rate before sending the binary to the scrambling unit.

Abstract: Data transmitter includes a first and second output nodes terminated to a first level, a controller configured to generate an off signal that is activated by logically combining first and second data during a low-power mode, a first driver configured to drive the first or second output node to a second level in response to the first data and a second driver configured to drive the first or second output node to the second level with a driving force different from that of the first driver in response to the second data, the second driver being turned off when the off signal is activated.

Abstract: A method for transmitting data in the form of pulse sequences, including a signal synchronization step carried out by a receiver of dataframes DF, in the course of which at least one time window ?T(0) is scanned in search of the beginning PSB of a pulse sequence. The time window is then subdivided into a predefined number of sub-windows ?T(1). The sub-windows are then scanned during further signal detection steps until the beginning PSB of the pulse sequence has been detected within one of the sub-windows which will then be substituted for the previous time window AT(0), until the width of the resulting sub-windows becomes smaller than a predetermined minimum width.

Abstract: A method and system is described wherein a signal with a lower frequency is up-converted to a higher frequency. In one embodiment, the higher frequency signal is used as a stable frequency and phase reference. In another embodiment, the invention is used as a transmitter. The up-conversion is accomplished by controlling a switch with an oscillating signal, the frequency of the oscillating signal being selected as a sub-harmonic of the desired output frequency. When the invention is being used as a frequency or phase reference, the oscillating signal is not modulated, and controls a switch that is connected to a bias signal. When the invention is being used in the frequency modulation (FM) or phase modulation (PM) implementations, the oscillating signal is modulated by an information signal before it causes the switch to gate the bias signal.

Abstract: The invention relates to methods by which radio signals can be transmitted to, and received by, a radio receiver such that the receiver consumes very little power from a battery or energy source. The invention also relates to methods by which radio signals, modulated with data information, can be produced by a transmitter that consumes very little power. The invention is applicable not only to medical implants, but any application requiring a radio receiver to operate with very low power consumption.

Abstract: In one aspect, a data communication system includes a modulator, an integrated acoustic data coupler, and a demodulator. The modulator modulates a carrier signal having a frequency in an operating frequency range in response to an input data signal and provides the modulated carrier signal at a modulator output. The integrated acoustic data coupler includes an acoustically resonant structure that has one or more acoustic resonant frequencies in the operating frequency range. The acoustically resonant structure includes a first thin film electro-acoustic transducer electrically coupled to the modulator output, a second thin film electro-acoustic transducer, and a substrate. The substrate supports, acoustically couples, and provides an electrical isolation barrier between the first and second thin film electro-acoustic transducers.

Abstract: The present invention provides a digital (computational) branch calibrator which uses a feedback signal sensed from an RF transmit signal path following the combining stage of LINC circuitry of a transmitter to compensate for gain and phase imbalances occurring between branch fragment signals leading to the combiner. The calibrator feeds a quiet (zero) base band signal through the transmit path during the calibration sequence (i.e. a period when data is not transmitted) and adjusts the phase and gain of the phasor fragment signals input thereto by driving the sensed output power to zero. The calibration is performed by alternating phase and gain adjustments with predetermined (programmable) and multiple update parameters stages (speeds). A baseband modulation is preferably used to distinguish false leakage (e.g. due to local oscillator, LO, feed through and DC offset in the base band Tx) from imbalance leakage.

Abstract: Transmitters supporting multiple modulation modes and/or multiple frequency bands are described. A transmitter may perform large signal polar modulation, small signal polar modulation, and/or quadrature modulation, which may support different modulation schemes and systems. Circuit blocks may be shared by the different modulation modes to reduce cost and power. For example, a single modulator and a single power amplifier may be used for small signal polar modulation and quadrature modulation. The transmitter may apply pre-distortion to improve performance, to allow a power amplifier to support multiple frequency bands, to allow the power amplifier to operate at higher output power levels, etc. Envelope and phase distortions due to non-linearity of the power amplifier may be characterized for different input levels and different bands and stored at the transmitter.

Abstract: Each of a first oversampling filter and a second oversampling filter oversamples to an n×m times as high frequency as a symbol rate. The first and second oversampling filters then output output data having a sampling frequency to first and second CIC filters, respectively.

Abstract: Provided is a transmitter circuit capable of operating with low distortion and high efficiency even in a modulation method using wide modulation bandwidth. In the transmitter circuit, a signal generation section (11) generates an amplitude signal and an angle-modulated signal. Based on a predetermined characteristic, a compensating filter (12) wave-shaping-processes the amplitude signal. A regulator (14) outputs a signal in accordance with a magnitude of the signal which has been wave-shaping-processed by the compensating filter (12). An amplitude modulator section (15) amplitude-modulates the angle-modulated signal by using the signal outputted from the regulator (14). A characteristic of the compensating filter (12) is an inverse of a transfer characteristic between an input at the regulator (14) and an output at the amplitude modulator section (15).

Abstract: A multi-mode transmission system supporting OFDM and single-carrier signals is configured to perform interpolation and decimation such that the ratio of the interpolation factor to the decimation factor equals the ratio between the OFDM sampling rate and the single-carrier chip rate. A constant-envelope modulator comprises a ?/4 fixed rotator, a ?/2 continuous rotator, and in-phase and quadrature-phase analog Bessel filters. Frame formats and signaling protocols are provided for signal acquisition, synchronization, and tracking between wireless devices that employ different antenna configurations. Spreading gains are selected to compensate for different antenna gains such that the total gain (antenna gain plus spreading gain) is substantially equal for transmissions employing different beam patterns.

Abstract: This invention is primarily a circuit structure of self-mixing receiver, and the methodology of circuit structure is described as follows. The first stage is a high input impedance voltage amplifier utilized to amplify the received RF carrier signal from the antenna. Besides, there are no any inductors required. The second stage is a multi-stage amplifier to amplify the output signal of first stage to rail-to-rail level, which is quite the same with supply voltage. The third stage is a mixer adopted to lower the signal frequency. The fourth stage is a digital output converter, which is proposed to demodulate the electric signals and convert the demodulated signal to digital signal.

Abstract: A method of modulation, which is applied to a communication system transmitting data in one frequency band using at least two orthogonal subcarriers, is disclosed. The present invention includes the steps of adding information bits indicating an amplitude reference and a phase reference to an input bit sequence by a specific time interval unit and carrying out differential amplitude phase shift keying (DAPSK) on the input bit sequence using the amplitude and phase references. The present invention prevents the waste of power and bandwidth due to insertion of a plurality of pilot toes in the related art 1?-QAM system.

Abstract: Mechanisms for reducing amplitude-modulated noise in a wireless transceiver are generally described. In one example, an apparatus includes a radio-frequency identification (RFID) transceiver, a digital-analog converter (DAC) coupled with the transceiver, a reconstruction filter coupled with the digital-analog converter, and hold logic associated with the reconstruction filter to enable the reconstruction filter to hold its output voltage.

Abstract: A communication system disclosed herein includes a channel quality estimation module that determines the channel quality metric utilizing the preamble portion of the packet only. Data, in such a communication system, is transmitted in the form of a packet over a data channel during a packet transmission, wherein each data channel includes several subchannels. The system includes a receiver having at least a baseband processor. The baseband processor couples to receive each baseband sample signal. Specifically, the baseband processor calculates the gain estimation of the each subchannel and generates a channel quality metric for each subchannel that is derived by deinterleaving the sequence of gain estimation magnitudes, convolving the deinterleaved sequence of gain estimation magnitudes with a short window index, and detecting the number of times the convolution falls beneath a predetermined threshold.

Abstract: A polar modulator arrangement has a first and a second node to receive a digital signal with a first and a second component corresponding to a digital amplitude component and a digital phase component. A digital interpolation filter generates an interpolated first component by interpolating and filtering the first component. A polar modulated radio frequency signal is generated by a combination element as a function of the interpolated first component and the second component.

Abstract: Systems, methods, and apparatus for reducing dynamic range requirements of a power amplifier in a wireless device are provided. An exemplary method may include modulating a symbol stream to generate a modulated waveform. The exemplary method may further include generating at least one pulse having a peak aligned with an anticipated position of a peak or a null corresponding to the modulated waveform, where the anticipated position of the a peak or the null corresponding to modulated waveform may be determined by detecting a transition in a phase or an amplitude of the modulated waveform.

Abstract: An amplitude component of a modulating signal is detected, band-divided by first and second frequency selecting circuits, and an amplitude component of a high-frequency band is down-converted by a first frequency conversion circuit. An amplitude component selected by the first frequency selecting circuit and an amplitude component selected by the first frequency conversion circuit are amplified by first and second operational amplifiers, and a signal amplified by the second operational amplifier is up-converted by a second frequency conversion circuit to be restored to the initial frequency band. Output amplitudes of the first operational amplifier and a second frequency converter are added up by an adder to be direct-current converted. The amplitudes after the direct-current conversion are band-divided by third and fourth frequency selecting circuits, respectively, feedback amounts thereof are adjusted, and then fed back to the first and second operational amplifiers.

Abstract: A pulse amplitude modulation (PAM) signal generator that injects a copy of a pulse into the PAM baseband signal prior to frequency upconversion and power amplification. The pulse comprises a function of, or an extra copy of, a pulse in the PAM baseband signal. The pulse injector analyzes the PAM baseband signal for times when a predetermined threshold is exceeded and forms a pulse that is constructed and arranged to reduce the amplitude of the PAM baseband signal to a desired peak amplitude when the pulse is added to the PAM baseband signal. In other embodiments the peak-to-RMS amplitude ratio reducing methods and apparatus used to process PAM signal are adapted for reducing peak-to-RMS amplitude ratios of amplitude modulation signals in polar modulation transmitters. Peak-to-RMS amplitude ratio reduction is performed in the quadrature domain, the polar domain, or both the quadrature and polar domains.

Abstract: A transmission signal generating circuit in a radio base station that employs spread processing circuits in order to output spread transmission signals. The signal generating circuit further contains power class selecting circuits, which categorize spread transmission signals into power classes, a first adding circuit, which combines these signals, multipliers, which adjust transmission power of these signals for respective power classes, and a second adding circuit, which combines these signals. The circuit measures and quantinizes the total transmission power to output a power level. A power limitation control memory outputs a multiplication coefficient representing the power class for which transmission power control. Selectors in the circuit select when this control is permitted for a given power class and output this information to the multiplier corresponding to the class.

Abstract: A first interpolation section 14 and a second interpolation section 24 perform sampling on input data Id4 and Qd4 having a sampling frequency fover so that resulting data will have a sampling frequency fsamp, which is equal to an operating clock frequency of a digital-to-analog converter, which is an output destination. In the above manner, the data is interpolated. At this time, the first interpolation section 14 and the second interpolation section 24 perform interpolation using a frequency ratio between the sampling frequency fover and the sampling frequency fsamp. Then, output data Id5 and Qd5 having the sampling frequency fsamp is outputted to a quadrature modulation section 31.

Abstract: In a communication device, the LO leakage and opposite side band signals are measured at an output signal. Input processing signals to a modulator are adjusted in response to the measured values to minimize the LO leakage and maximize side band suppression.

Abstract: A method for transmitting digital data from a substantially sinusoidal waveform containing encoded digital data having one of a first and second value at selected phase angles ?n comprises generating the waveform with amplitude Y defined by a first function at phase angles lying outside of data regions, the first function being Y=sin ?, generating the waveform with amplitude Y defined by the first function at phase angles lying inside the data regions having a range of ?? beginning at each phase angle ?n where data of the first value is to be encoded, generating the waveform having an amplitude Y defined by a second function different from Y=sin ? at phase angles lying inside the data regions having a range of ?? associated with each phase angle ?n where data of the second value is to be encoded, and transmitting at least one harmonic of the waveform containing encoded digital data.

Abstract: A transmitter adopting a polar loop system including a phase control loop for controlling the phase of a carrier signal outputted from a transmitting oscillator and an amplitude control loop for controlling the amplitude of a transmitting output signal outputted from a power amplification circuit, and designed to be capable of performing transmission using a GMSK modulation mode and transmission using an 8-PSK modulation mode. In the transmitter, the phase control loop is shared as a phase control loop for use in the GMSK modulation mode and a phase control loop for use in the 8-PSK modulation mode. A component similar to any one of components constituting a loop filter is provided in parallel therewith so that the component can be connected or disconnected in accordance with the modulation mode, for example, by use of a switching element.

Abstract: A pre-emphasis automatic adjusting system is provided which is capable of placing the best suitable emphasis against attenuation occurring in a through hole. A step signal is transmitted from a transmitting circuit via a signal transmission path to a receiving circuit with termination of the receiving circuit being released. A voltage of its reflected signal is compared with a first reference voltage of a first reference voltage source. Based on a comparison result in a capacitive reflection section in which a voltage of the reflected signal is less than the first reference voltage, a section detecting signal is outputted from a reflected wave detecting circuit.

Abstract: A radio frequency (RF) transmitter uses two digital-to-RF conversion modules to convert digital baseband signals into RF signals. In cartesian mode, baseband signals are conveyed to the conversion modules for RF conversion. In polar mode, baseband signals are converted into amplitude and phase data parts. Phase data part is converted into I (inphase) and Q (quadrature) data parts to be converted into RF signals which are modulated in a power amplifier by amplitude data part through the power supply of the power amplifier. Each digital-to-RF module uses parallel unit cells to perform digital-to-analog (D/A) conversion and upconversion functions by an IF signal. Each unit cell, adapted to receive a control voltage indicative of a data signal value, is a mixer cell type converter having a differential data switch section connected in series to a differential LO (local oscillator)-switch pair. LO-switch is further connected in series to a current source.

Abstract: Interactive touch screen controlled communication systems for single or multimode communications and broadcasting. Processor for processing multiple touch screen signals, obtained by touching the screen of a device. Processor for receiving and processing multiple signals received from multiple locations and for generating a processed position finder signal. Processor and filter for generating time division processed filtered signal used in Time Division Multiple Access (TDMA) Global Mobile System (GSM), Enhanced Digital GSM Evolution (EDGE), in Code Division Multiple Access (CDMA) and in Orthogonal Frequency Division Multiplex(OFDM), Wi-Fi wireless fidelity (Wi-Fi) systems. Processor for generating cross-correlated in-phase and quadrature-phase processed filtered baseband signals from an input signal. Processor for generating a signal from processing of the processed touch screen signal with processed position finder signal and with one or more of the signals generated by the other processors.

Abstract: A rf signal transfer link is described which uses amplitude shift keying (ASK) to transfer rf data pulses. The link minimizes state transition time at the end of each data pulse.

Abstract: A polar modulator including a signal converter configured to provide a phase signal and an amplitude signal based on at least one received signal is disclosed. A digital-to-analog converter is coupled to the signal converter, the digital-to-analog converter configured to receive an augmented signal, wherein a polarity of the augmented signal is selected to minimize an absolute phase change for sequential signals. A signal mixer is coupled to the digital-to-analog converter to receive an analog signal generated from the augmented signal.

Abstract: A system and method for encoding and receiving data is provided. The data is encoded as a pulse amplitude modulated signal such that the amplitude signals do not transition from the highest signal level to the lowest signal level and do not transition from the lowest signal level to the highest signal level. The encoding and decoding is performed in some embodiments via a lookup table, and in further embodiments is designed to minimize the step between sequential pulse amplitude modulated symbols.

Abstract: A transmitter modulator that is operable to modulate signals according to multiple modulation formats includes a first modulator, a second modulator, and a polarization beam combiner. The first modulator encodes a first signal according to a first modulation format. The second modulator encodes a second signal according to a second modulation format, the first signal orthogonally polarized with respect to the second signal. The polarization beam combiner combines the first signal and the second signal for transmission.

Abstract: A transmitter for broadcasting an AM compatible digital audio broadcasting signal includes an analog modulator for producing an analog modulated carrier signal centrally positioned in a radio channel, wherein the analog modulated carrier signal is modulated by an analog signal, and a digital modulator for producing a plurality of digitally modulated subcarrier signals in the radio channel, wherein the digitally modulated subcarrier signals are modulated using complementary pattern-mapped trellis code modulation including a code mapped to overlapping partitions. In a first operating mode the analog modulated carrier signal and the plurality of digitally modulated subcarrier signals are in a 20 kHz channel and in a second operating mode the analog modulated carrier signal and the plurality of digitally modulated subcarrier signals are in a 30 kHz channel.

Abstract: A transmitter provides a plurality of output signals. The transmitter includes a processor, a modulator, a first circuit, and a second circuit. The modulator provides a modulated signal responsive to the processor. The modulated signal includes an amplitude modulated radio frequency for transmitting a pulse. The first circuit provides a first output signal, responsive to and with higher power than the modulated signal. The first output signal has a first phase during transmitting of the pulse. The second circuit provides a second output signal, responsive to and with higher power than the modulated signal. The second output signal has a second phase during transmitting of the pulse. The second phase is controlled by the second circuit in accordance with the first phase, the second phase, and indicia of a third phase provided by the processor.

Abstract: The present invention, generally speaking, provides for high-efficiency power control of a high-efficiency (e.g., hard-limiting or switch-mode) power amplifier in such a manner as to achieve a desired modulation. In one embodiment, the spread between a maximum frequency of the desired modulation and the operating frequency of a switch-mode DC-DC converter is reduced by following the switch-mode converter with an active linear regulator. The linear regulator is designed so as to control the operating voltage of the power amplifier with sufficient bandwidth to faithfully reproduce the desired amplitude modulation wave-form. The linear regulator is further designed to reject variations on its input voltage even while the output voltage is changed in response to an applied control signal. This rejection will occur even though the variations on the input voltage are of commensurate or even lower frequency than that of the controlled output variation.

Abstract: In a transmitter of the present invention, a modulated signal is separated into an amplitude component and a phase component which are inputted to a radio-frequency modulated signal input terminal and a supply voltage terminal of a radio-frequency power amplifier. A voltage adjustment circuit is provided between an output terminal of the radio-frequency power amplifier and an amplitude amplification circuit having a feedback circuit. The voltage adjustment circuit changes the amount of isolation in accordance with the voltage level of the amplitude component. By this, the amplitude component of the radio-frequency modulated wave attenuates the level inputted to the feedback circuit of the amplitude amplification circuit through the supply voltage terminal of the radio-frequency power amplifier.

Abstract: Provided is a modulation-index adjustable amplitude shift keying (ASK) transmitter including: a bias current supply unit supplying one or more bias currents in response to a digital signal that is to be transmitted and one or more bias current control signals; and a modulation signal generator generating a modulation signal corresponding to the digital signal by modulating a carrier signal in response to the one or more bias currents.

Abstract: Aspects of a method and system for enhancing efficiency by modulating power amplifier (PA) gain are presented. Aspects of the system may comprise a PA gain modulator that enables modification of an amplitude of a digital baseband signal. A baseband processor may enable computation of a first gain value based on the modification. The baseband processor may enable computation of a second gain value based on the first gain value. A PA may enable generation of an RF output signal based on the modified digital baseband signal and the second gain value.

Abstract: A transceiver at one end of a variable data rate, time division duplex (TDD), adaptively modulated, point-to-point radio link transmits one or more pulses at different amplitude levels during a settling period of the transceiver's power amplifier. The highest level of the pulses is set to a level higher than the mean level of an OFDM symbol in a transmit burst immediately following the transmitted pulses, and is incrementally increased with each successive burst. A second transceiver at the opposite end of the link receives the transmitted pulses as time domain samples, normalizes the samples, and performs a cross correlation of the samples corresponding to the received pulses. When the cross correlation indicates that the power amplifier is operating at a maximal power level with regard to the amplifier linearity and the modulation mode and coding rate currently in use, the incremental increase of the transmission power ceases.

Abstract: A digital amplitude modulation (AM) transmitter with pulse width modulating RF drive is presented. A plurality of RF amplifiers, each, when turned on, amplifies an applied RF drive signal by the same amount to provide a unit step RF output. An encoder supplies turn-on signals to turn on a number of the RF amplifiers wherein the number varies as a function of the value of an applied audio signal. The width of the unit step RF output is varied as a function of the number of the RF amplifiers that are turned on.

Abstract: Either linear operating mode or saturation operating mode is set as the operating mode of a high-frequency power amplifier on the basis of an operating mode set signal. The gain of a variable gain amplifier provided in front of the high-frequency power amplifier and values of output voltage and bias current supplied from a supply voltage/bias current control circuit to the high-frequency power amplifier are switched. The gain of the variable gain amplifier in the saturation operating mode is formed so as to be higher by a predetermined value than that in the linear operating mode. Accordingly, the high-frequency power amplifier operates in the designated operating mode, so that the output transmission power range can be widened.

Abstract: An input digital signal is periodically and alternately subjected to first modulation and second modulation, being thereby converted into a pair of a baseband I signal and a baseband Q signal. The first modulation and the second modulation are different from each other. The pair of the baseband I signal and the baseband Q signal are outputted. The first modulation may be at least 8-signal-point modulation while the second modulation may be phase shift keying.

Abstract: A transmission stage in polar loop technology includes an amplitude regulation means, a phase regulation means, a VCO and a feedback path. In the feedback path a variable amplifier is provided. The amplitude regulation means is further implemented in order to be controlled by a control means according to a request for a power variation in the output signal of the amplifier in order to correspondingly vary an amplitude control signal for the power amplifier. Simultaneously, the control means is implemented in order to correspondingly control the variable feedback path amplifier, so that the amplitude of the output signal of the variable feedback path amplifier remains in a narrowly limited predetermined range. Thus, power variations in the output signal of the amplifier operated in the non-linear area are held remote from the phase locked loop, so that the phase regulation means may be implemented at low cost and operates reliably anyway.

Abstract: A method and apparatus for wireless data transmission between a base station and one or more, in particular, passive and/or backscatter-based transponders, in which the base station modulates a carrier signal with a modulation signal, to generate synchronization markers, and transmits the modulated carrier signal. Whereby, a frequency of the modulated carrier signal can be switched between different frequency values.

Abstract: A remote transmitter system for vehicle applications includes a remote transmitter for carrying by a user and a receiver for mounting on a vehicle and receiving an amplitude modulated signal. The transmitter is operative to transmit the amplitude modulated signal at a plurality of different carrier frequencies. The receiver is programmed to select the carrier frequency for reception by detecting noise due to unwanted frequency modulated signals based on a received signal strength indicator, and detecting noise due to unwanted amplitude modulated signals based on a data decoder. The receiver changes the selected carrier frequency when either noise becomes excessive.

Abstract: In one exemplary embodiment of the invention, an outphasing modulator may include at least a multiplier to multiply an amplitude modulation signal by a phase modulated carrier signal to generate a modulated signal. The outphasing modulator may also include a phase splitter to phase split the modulated signal to generate phase shifted modulated signals. The outphasing modulator may also include a sum-difference combiner to produce outphased modulated signals from the phase shifted modulated signals.

Abstract: When a transmitting oscillator is built in a communication semiconductor integrated circuit device like a high-frequency IC constituting a wireless communication system, the system prevents degradation of the accuracy of control on the output power of a power amplifier due to noise jumped from an output pin of the transmitting oscillator to an input pin for a detected signal (feedback signal) of an output level of the power amplifier. The transmitting oscillator is built in the high-frequency IC. The detected signal of the output level of the power amplifier, which is detected by a coupler, is attenuated to a level slightly higher than the level of noise jumped from the output pin of the transmitting oscillator to the input pin for a feedback signal of an amplitude control loop, which in turn is inputted to the feedback signal input pin of the high-frequency IC.