Abstract: An integrated circuit comprises a digitally-controlled power generation stage (DPA) for converting an input signal to a radio frequency (RF) carrier, the DPA comprising a plurality of selectable switching devices capable of adjusting an envelope of the RF carrier; and a pulse width modulator (PWM) generator arranged to generate a PWM control signal and operably coupleable to the plurality of selectable switching devices of the DPA. The PWM generator inputs the PWM control signal to a subset of the plurality of the selectable switching devices such that a PWM signal adjusts the envelope RF carrier output from the DPA.

Abstract: In a communication system including a RFID tag, which has a function to record information and a function to carry out wireless communication with an external device and is capable of transmission with using both FM modulation and AM modulation, and a reader/writer for writing and reading information onto and from the RFID tag via wireless communication, a transmission to transmit information from the RFID tag to the reader/writer is carried out with using one of the FM modulation and the AM modulation at the RFID tag. If the reader/writer fails to decode a signal transmitted with using the one of the FM modulation and the AM modulation, transmission with respect to the information is carried out with using the other of the FM modulation and the AM modulation at the RFID tag. In this manner, reading error of data sent from the RFID tag is prevented.

Abstract: A user equipment, for use in a wireless communication system, includes a unit operable to measure a received signal quality in a receiver, a unit operable to report the measuring received signal quality to the transmitter, or a unit operable to report a selected modulation and coding scheme to the transmitter.

Abstract: A transmitter is provided. The transmitter includes a phase/frequency deviation input, a controller and a frequency modulating path. The phase/frequency deviation input receives multiple phase/frequency deviation samples. The controller outputs a modified phase/frequency deviation signal and generates a phase/frequency deviation carry-out signal in response to the phase/frequency deviation samples and a previous time sample of the phase/frequency deviation carry-out signal. The frequency modulating path performs frequency modulation in response to the modified phase/frequency deviation signal and outputs a frequency modulated carrier signal.

Abstract: Provided is a transmission circuit that operates highly efficiently by avoiding deterioration of the linearity of an output signal and suppressing occurrence of distortion of the output signal, when using the envelope tracking method. In this transmission circuit, offset control section (160) sets voltage that makes the corrected envelope signal level equal to or higher than the delayed envelope signal level, as offset voltage. By this means, the corrected envelope signal level becomes equal to or higher than the delayed envelope signal level, so that it is possible to prevent the power supply voltage from being lower than the optimal power supply voltage, making it possible to prevent the linearity of an output signal from deteriorating in power amplifier (130).

Abstract: A distortion compensation device includes a distortion compensator that predistorts an input signal based on delay signals and distortion compensation coefficients corresponding to the respective delay signals obtained by applying different amounts of delay to the input signal, a calculator that calculates an error signal based on the predistorted input signal and an output signal from an amplifier that amplifies the predistorted input signal, a calculator that calculates prospective distortion compensation coefficients for updating the distortion compensation coefficients, based on the error signal, a saturation processor that performs saturation processing for bringing, when the prospective distortion compensation coefficients do not fall into a preset range, the prospective distortion compensation coefficients into the preset range, and a controller that controls the updating of the distortion compensation coefficients based on pieces of coefficient saturation information indicating whether the saturation

Abstract: A signal separating unit separates an input signal into a first branch signal and a second branch signal in such a manner that, as the amplitude of the input signal decreases, the amplitude of the first branch signal and the second branch signal decreases and the difference between a phase of the first branch signal and a phase of the second branch signal increases and, as the amplitude of the input signal increases, the amplitude of the first branch signal and the second branch signal increases and the difference between the phase of the first branch signal and the phase of the second branch signal decreases. An amplifier amplifies the first branch signal. Another amplifier amplifies the second branch signal. A combining unit combines signals that are output from the amplifiers together, thereby generating an output signal.

Abstract: Configurable suppression of harmonics in a radio frequency (RF) transmitter circuit having two class-D switching amplifiers that produce a differential output signal having introduced harmonics is contemplated. A selected harmonic is used to determine a time duration. A harmonic suppression circuit modifies a radio frequency polar modulated data signal that is encoded using an amplitude component and a phase component. The modification is responsive to the determined time duration. The switching power amplifiers amplify the modified polar modulated data signal to produce an amplified signal. The amplified signal includes three signal levels, a high signal level, a middle signal level and a low signal level. The timing of transitions between the high and low signal levels represents the phase component, and the transitions include the middle signal level for the time duration, thereby suppressing the selected harmonic.

Abstract: A circuit is provided comprising detector circuitry, calculating circuitry, and determining circuitry. The detector circuitry is figured to generate an I data signal magnitude value of a sampled I data signal and a Q data signal magnitude value of a sampled Q data signal. The calculating circuitry is configured to calculate a phase shift angle ?I between first and second equal and constant or substantially equal and constant envelope constituents of the sampled I data signal and to calculate a phase shift angle ?Q between first and second substantially equal and substantially constant envelope constituents of the sampled Q data signal. The determining circuitry is configured to determine in-phase and quadrature amplitude information of the substantially equal and substantially constant envelope constituents of the sampled I signal and to determine in-phase and quadrature amplitude information of the first and second substantially equal and substantially constant envelope constituents of the sampled Q signal.

Abstract: Disclosed are a method and an apparatus for transmitting and receiving broadcast data in a digital broadcasting system. The method for transmitting and receiving broadcast data in a digital broadcasting system includes receiving the main data encoded with symbols having a plurality of levels; deciding whether levels of main data symbols encoded with symbols having the plurality of levels belong to a first group; and mapping the main data symbols to extended levels by using modulation values of the additional data if it is decided that the levels of the main data symbols belong to the first group.

Abstract: A system includes a voltage regulator connected to a voltage source for providing a regulated voltage at a first level in a first mode of operation and at least one second level in a second mode of operation. The second voltage level is higher than the first voltage level. A control processor provides control signals to select between the first and the second modes of operation. A component associated with the voltage regulator. The component is disabled in the first mode of operation and enabled in the second mode of operation. The control processor generates control signals to configure the voltage regulator to generate the voltage at the first level in the first mode of operation when the component is disabled and to configure the voltage regulator to generate the voltage at the at least one second level in the second mode of operation when the component is enabled.

Abstract: This invention provides a power amplifier (100) including a signal source control unit (110) which generates and outputs an amplitude signal serving as the amplitude modulated component of an input signal and a pulse modulated signal based on the amplitude signal, and outputs a transmission signal obtained by superposing the input signal on a carrier, a delay adjustment unit (120) which synchronizes the amplitude signal, pulse modulated signal, and transmission signal with each other, a voltage signal generation unit (130) which outputs a voltage signal corresponding to the amplitude signal synchronized with the transmission signal, a current signal generation unit (140) which outputs a current signal corresponding to the pulse modulated signal synchronized with the transmission signal, and a transmission signal amplification unit (150) which amplifies the transmission signal, and outputs a transmission signal obtained by modulating the amplitude of the amplified transmission signal based on a modulated power

Abstract: A communications device may include In-phase (I) power amplifiers configured to respectively generate I amplified signals, Quadrature (Q) power amplifiers configured to respectively generate Q amplified signals, I antennas respectively coupled to the I power amplifiers, and Q antennas respectively coupled to the Q power amplifiers. The communications device may also include an I controller coupled to the I power amplifiers and configured to selectively enable some of the I power amplifiers, and a Q controller coupled to the Q power amplifiers and configured to selectively enable some of the Q power amplifiers.

Abstract: A polar modulator for generating a polar-modulated signal based on amplitude information and phase information includes a phase-locked loop which is implemented to enable a setting of a frequency depending on a control value to obtain a phase-locked loop output signal. The polar modulator further includes a modulation means which is implemented to combine an amplitude modulation signal derived from the amplitude information with the phase-locked loop output signal to generate the polar-modulated signal. The polar modulator further includes a control value generator which is implemented to high-pass filter an amplitude signal derived from the amplitude information, to obtain a high-pass filtered amplitude signal, wherein the control value generator is implemented to combine the high-pass filtered amplitude signal with a phase signal based on the phase information to generate the control value signal representing the control value.

Abstract: A method of reporting received signal quality to a transmitter includes measuring a received signal quality in a receiver, and selectively performing the steps of reporting the received signal quality to the transmitter, and reporting a selected modulation and coding scheme to the transmitter.

Abstract: An apparatus is disclosed having a receiver configured to communicate, by a first apparatus, with a second apparatus in a first mode; determine side information by the first apparatus based on the communication during the first mode; and store the side information by the first apparatus for communication in a second mode with the second apparatus, wherein the first and second modes of communication have different date rates. A method for wireless communications is also disclosed.

Abstract: The radio transmitting apparatus includes a first initial phase value setting circuit that sets, in the first modulator, an initial value of the phase of the first modulated signal, which is a value at the start of the modulation according to the first modulation scheme. The radio transmitting apparatus includes a second initial phase value setting circuit that sets, in the second modulator, the phase stored in the phase storing circuit as an initial value of the phase of the second modulated signal, which is a value at the start of the modulation according to the second modulation scheme. The radio transmitting apparatus includes a signal gathering circuit that selects and outputs the first modulated signal output from the first modulator and then selects and outputs the second modulated signal output from the second modulator.

Abstract: Exemplary embodiments are directed to forward link signaling. A method may include modulating an input bias signal of a power amplifier according to data to be transmitted on a wireless power transmit signal. The method may further include modulating an amplitude of the wireless power transmit signal generated by the power amplifier in response to the modulated input bias signal.

Abstract: A communications device may include an In-phase (I) power amplifier configured to generate an I amplified signal, a Quadrature (Q) power amplifier configured to generate a Q amplified signal, an I digital-to-analog converter (DAC) configured to generate an I signal, and a Q DAC configured to generate a Q signal. The communications device may also include an I power supply circuit coupled to the I power amplifier and to the I DAC and configured to cause the I power amplifier to modulate an I carrier signal into the I amplified signal based upon the I signal, a Q power supply circuit coupled to the Q power amplifier and to the Q DAC and configured to cause the Q power amplifier to modulate a Q carrier signal into the Q amplified signal based upon the Q signal, and at least one antenna coupled to the I and Q power amplifiers.

Abstract: An AM (Amplitude-Modulated) transmitter capable of improving modulation distortion is provided. An adder adds a modulation signal to a pre-set power reference signal. An APC (Automatic Power Control) amplifier compares a level of a detecting signal outputted by the LPF (Low Pass Filter) with a level of an adder signal. The APC amplifier, based on the comparison result, generates a gain controlling signal that makes a difference between a level of the detecting signal and level of the signal approach zero and feeds the gain controlling signal to a power amplifier. The power amplifier modulates the signal outputted from the amplifier by the gain controlling signal and power-amplifies the modulated signal according to a level of the gain controlling signal. Since the APC amplifier feeds the gain controlling signal to the power amplifier, a modulation degree does not depend on a nonlinear distortion characteristic of the power amplifier.

Abstract: Various embodiments are disclosed relating to power control techniques for wireless transmitters. In an example embodiment, an apparatus is provided that may include a digital-to-analog converter (DAC) adapted to convert a digital amplitude signal to an analog amplitude signal during a first transmission mode and adapted to convert a digital power level signal to an analog power level signal during a second transmission mode.

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: A feedback loop is used to determine phase distortion created in a signal by directly extracting the phase distortion information from a feedback signal using original frequency modulation information.

Abstract: Various embodiments provide for systems and methods for wireless communications that implement transmitter protection schemes using spatial combining. The protection scheme implemented by some embodiments provides for a number of benefits, including without limitation: hitless protection; constant power monitoring for each wireless channel being utilized; extra gain to wireless signals transmitted; beam steering, beam hopping, and beam alignment capabilities; and varying levels of transmission path protection (e.g., 1+1 protection, or 1+N protection). Additionally, the features of some embodiments may be applied to a variety of wireless communications systems including, for example, microwave wireless systems, cellular phone systems and WiFi systems.

Abstract: A transmitter for transmitting a transmission signal is disclosed. The transmitter includes: a gain stage, for receiving an input signal and amplifying the input signal according to a gain to generate an amplified signal; and an output stage, coupled to the gain stage, for receiving a first reference voltage signal and the amplified signal and utilizing the first reference voltage signal to perform a predetermined operation on the amplified signal to generate the output signal.

Abstract: Provided is a transmission circuit capable of compensating a variation in output power caused due to a temperature change or an individual variability when the operation mode is switched without an increase in the size of the transmission circuit which switches the operation mode between a linear operation mode and a nonlinear operation mode, and capable of suppressing the deterioration of the quality of a transmission signal. In the transmission circuit, a gain setting section (160) sets the gain (target gain) of a variable gain amplifier (140), to a value which enables the variable gain amplifier (140) to operate linearly and corresponds to a comparison result (output error level) obtained through comparison between the target level of the variable gain amplifier (140) corresponding to the set power level of the transmission signal and the power level of an output signal of the variable gain amplifier (140) detected by a power detection section (150).

Abstract: According to one exemplary embodiment, a method for producing an up-converted and amplified transmission signal comprises performing a logarithmic transformation of an input transmission signal to form a logarithmically transformed transmission signal, adding the logarithmically transformed transmission signal to a logarithmic local oscillator signal to form a sum signal, and performing an antilogarithmic transformation of the sum signal to produce the up-converted and amplified transmission signal. In one embodiment, a log-antilog circuit for producing an up-converted and an amplified transmission signal comprises a transmission log block configured to receive an input transmission signal and to provide a logarithmically transformed transmission signal as a transmission log block output, and an antilog block coupled to the transmission log block. The antilog block is configured to receive a sum signal of the transmission log block output and a logarithmic local oscillator signal.

Abstract: A modulation system comprising a signal processing unit and a modulator. The signal processing unit may generate a low frequency modulator signal, a high frequency modulator signal, and a modulator amplitude control signal. The modulator may generate a modulated signal for transmission via a wireless network based, at least in part, on the low frequency modulator signal, the high frequency modulator signal, and the modulator amplitude control signal. The signal processing unit comprises a delay compensation unit for delaying the generation of the high frequency modulator signal and the modulator amplitude control signal based, at least in part, on signal generation and modulation path delays associated with the low frequency modulator signal to substantially align the modulator signals at the output of the modulation system.

Abstract: A radio communication system including a system computer connected to a radio communication device including a radio communication antenna and an audio management system via a data bus. The audio management system is connected to a user communication device. The system computer is arranged to switch between a data communication service and a voice communication service upon receiving a signal from the radio communication device indicating that a carrier on a predetermined fixed frequency has been detected or has ceased to be detected by the radio communication device, or from the audio management system indicating that a request for a predetermined fixed frequency voice communication service has been detected or has ceased to be detected by the audio management system.

Abstract: A mobile wireless communications device may include a portable housing, and a supply modulator carried by the portable housing. The supply modulator may include an output node, a linear amplifier coupled to the output node, and a switching amplifier also coupled to the output node. The switching amplifier may include at least one sensing transistor configured to sense current output from the linear amplifier and generate a drive voltage, and a hysteretic comparator coupled to the at least one sensing transistor and configured to be driven by the drive voltage. The mobile wireless communications device may also include a radio frequency (RF) power amplifier coupled to the output node of the supply modulator, and a wireless transceiver carried by the portable housing and coupled to the RF power amplifier.

Abstract: A power amplifying apparatus has a bandwidth limitation process circuit to which an envelope signal included in a transmission signal is inputted, and which performs a bandwidth limitation process on the envelope signal, a variable power supply circuit for generating a power amplifier supply voltage based on a voltage control signal generated by the bandwidth limitation process circuit, and a power amplifier which is fed an input signal, and which is driven in accordance with the supply voltage from the variable power supply circuit.

Abstract: A multi-mode communications transmitter includes a signal decomposer that converts rectangular-coordinate in-channel and quadrature channel signals into polar-coordinate amplitude and angle component signals and form therefrom first and second modulation signals. The signal decomposition process performed by the signal decomposer combines envelope-reduction and restoration (ERR) with filtering to reduce the bandwidths of the first and second modulation signals compared to the bandwidths of the unmodified amplitude and angle component signals. The reduction in signal bandwidths eases the design requirements of the electrical components needed to process and generate the signals applied to the power supply and radio frequency (RF) input ports of the multi-mode communications transmitter's power amplifier (PA).

Abstract: System for generating a pulsed signal of the ultra wideband type, comprising a device for direct digital frequency synthesis (DDS) comprising a phase accumulator (ACCP) able to deliver at a first frequency (Fclk) phases coded on i bits and spaced apart by a phase increment (?p) differing by a power of two and situated in the vicinity of 2i-1, processing means (MT) able to receive said phases and arranged so as to deliver an amplitude-modulated output signal (SG) whose envelope exhibits a succession of regions respectively delimited by zones of zero amplitude (ZA, ZB), each amplitude-modulated signal part situated in one of said regions forming a pulse of the ultra wideband type (IMP) whose central frequency is equal to said first frequency and whose width depends on the value of the phase increment, and control means (MC) able to regulate the operation of the digital synthesis device so as to selectively deliver one or more pulses of the ultra wideband type.

Abstract: A method for controlling power amplifiers for digital transmission includes converting a digital modulation signal according to envelope elimination and restoration into an amplitude signal and into a phase-modulated carrier signal. The amplitude signal and the phase-modulated carrier signal are combined in a final stage so as to provide a transmit signal. The amplitude signal is automatically monitored by a module that employs a distribution-density function of the amplitude signal in order to determine a direct component error of the amplitude signal. The distribution-density function of the amplitude signal corresponds to a Rayleigh function if the energy of the complex modulation signal is distributed approximately uniformly within a bandwidth being used. If the spectral power density has an approximately rectangular form, the Rayleigh function is used to determine the direct component error. The direct component error is determined from the amplitude signal.

Abstract: A method, system, apparatus and article are described for optimizing transformer power combiners and for dynamically controlling power for outphasing power amplifiers. In some embodiments, for example, an apparatus may comprise one or more outphasing power amplifiers, one or more phase modulator modules coupled to and operative to dynamically control the one or more outphasing power amplifiers, and one or more power combiners coupled to and operative to combine outputs from the one or more outphasing power amplifiers, wherein the one or more power combiners comprise transformer power combiners arranged to combine outphasing signals using a primary inductor and differential signals using a secondary inductor. Other embodiments are described and claimed.

Abstract: To provide a power amplifier circuit which is capable of reducing a phase error of an output signal in a case where an amplitude of an input signal is relatively small, as well as a transmitter and a wireless communication device using the same. A constant envelope signal generation circuit (20) converts an input signal (Si) having envelope variation into a first constant envelope signal (Sd1) and a second constant envelope signal (Sd2) having the same amplitude and different phases, and outputs the signals. A first amplifier (11) amplifies the first constant envelope signal (Sd1). A second amplifier (12) amplifies the second constant envelope signal (Sd2). An output adder (13) outputs an amplified output signal having envelope variation based on the amplified signals output from the first amplifier (11) and the second amplifier (12).

Abstract: Apparatus for generating a modulation signal for use in modulating the power supply of a power amplifier uses coarse and fine control for controlling the amplitude of the modulation signal, and thereby controlling the output power of the power amplifier. The modulation signal may be generated in the digital domain and converted to the analog domain by a digital-to-analog converter, with the digital-to-analog converter providing the fine control and a variable gain amplifier providing the coarse control of the analog signal.

Abstract: To provide a power amplifier circuit, which is capable of amplifying a signal having envelope variation with high power added efficiency, and exhibits low power consumption and high versatility, as well as to provide a transmitter and a wireless communication device using the power amplifier circuit, the power amplifier circuit includes: a constant envelope signal generation circuit (20) for converting an input signal (Si) having envelope variation into two constant envelope signals (Sd1, Sd2); a first and a second amplifiers (11, 12) for amplifying the two constant envelope signals to output two amplified signals (Sh1, Sh2); and an output adder (13) for performing vector addition of the two amplified signals.

Abstract: Apparatus and methods configure digital predistortion linearizers for power amplification of bandlimited signals using non-linear amplifiers. The predistorter is configured to achieve both crest factor reduction (CFR) and predistortion for linearization. One embodiment advantageously reduces processing requirements conventionally associated with CFR by considering only the in-band component, that is, the information bearing component, of the desired signal to be reproduced for those cases in which the mitigation of in-band error vector magnitude (EVM) is preferred over the reduction of spurious out-of-band emissions.

Abstract: A signal generating section 10 outputs an amplitude signal and a frequency signal by conducting a signal processing on inputted data. A regulator 31 outputs a signal that is proportional to a magnitude of the amplitude signal. The signal outputted from the regulator 31 passes through a low pass filter 41, and is inputted into a power amplifier 51. The power amplifier 51 conducts an amplitude modulation on a frequency signal on which an angle modulation is conducted by an angle modulation section 20, using a signal outputted from the low pass filter 41. A controlling section 60 controls an amount of attenuation of a radio frequency component at the low pass filter 41 based on information such as: a modulation method of the inputted data; a modulation condition of the inputted data; a reception band; an output power of a modulation signal; and a frequency of the modulation signal.

Abstract: A method and apparatus for generating a carrier frequency signal is disclosed. The method includes generating a first frequency signal; injecting a modulation signal at a first point of the two-point modulation architecture; generating a second frequency signal from the modulation signal; introducing the second frequency signal by mixing the first frequency signal and the second frequency signal to generate a mixed frequency signal and outputting the carrier frequency signal selected from the mixed frequency signal.

Abstract: Implementations of a high gain range transmitter with variable-size mixers are described.

Abstract: Digital transmitters having improved characteristics are described. In one design of a digital transmitter, a first circuit block receives inphase and quadrature signals, performs conversion from Cartesian to polar coordinates, and generates magnitude and phase signals. A second circuit block (which may include a delta-sigma modulator or a digital filter) generates an envelope signal based on the magnitude signal. A third circuit block generates a phase modulated signal based on the phase signal. The third circuit block may include a phase modulating phase locked loop (PLL), a voltage controlled oscillator (VCO), a saturating buffer, and so on. A fourth circuit block (which may include one or more exclusive-OR gates or an amplifier with multiple gain states) generates a digitally modulated signal based on the envelope signal and the phase modulated signal.

Abstract: A mobile terminal and method of controlling a driving voltage of a power amplifier therein are provided. The present invention includes a power amplifier module having a plurality of operative modes, the power amplifier module configured to amplify a power strength of an RF signal, a modem configured to deliver the RF signal to the power amplifier module, and to control the operative modes of the power amplifier module, a power detecting unit configured to output a reference voltage by detecting the power strength of the RF signal outputted from the power amplifier module, and a DC/DC converter configured to supply a driving voltage to the power amplifier module by adjusting a detected power value according to a gain corresponding to each of the operative modes of the power amplifier module.

Abstract: An apparatus for wireless communications is disclosed including a signal generator adapted to generate a substantially periodic signal including a plurality of cycles, and a modulator adapted to modulate an amplitude, a phase or both the amplitude and the phase of the periodic signal on a per cycle basis. In one aspect, the modulator is adapted to modulate the amplitude, the phase, or both the amplitude and phase of the periodic signal with a defined modulation signal. In another aspect, the defined modulation signal includes a substantially root raised cosine signal. In yet another aspect, the defined modulation signal is configured to achieve a defined frequency spectrum for the modulated periodic signal.

Abstract: A system for calibrating a closed power control loop includes an adder configured to inject a test signal into an adjustable element, a first peak detector configured to determine an amplitude of the injected test signal, a second peak detector configured to determine an amplitude of a return test signal, a comparator configured to determine the difference between the injected test signal and the return test signal, and a calibration engine configured to adjust the adjustable element so that the return test signal is offset from the injected test signal by a predetermined amount.

Abstract: A transmitter circuit is provided which is capable of reducing modulation distortion even when an output power of a power amplifying section 141 is low. A signal generation section 11 generates an amplitude signal and a phase signal. A regulator 12 outputs a current based on the amplitude signal. A phase modulation section 13 phase-modulates the phase signal, and outputs a phase-modulated signal. The power amplifying section 141 receives the current which is based on the amplitude signal and supplied as a bias current from the regulator 12, and amplifies the phase-modulated signal by using the supplied current. Further, to the power amplifying section 141, a predetermined DC voltage is supplied as a collector voltage.

Abstract: A power amplifier circuit can be linked to an antenna arrangement of a communication system for transmission of ASK RF data signals. The power amplifier circuit includes an amplifier core with several cascode amplifier cells in parallel. Each cascode amplifier cell is composed of three NMOS transistors in triode mounting between an output terminal connected to the antenna arrangement, and an earth terminal. A first transistor of each cascode amplifier cell is controlled by a carrier frequency signal, whereas a second transistor of each cascode amplifier cell is controlled by a smoothing control loop in order to modulate data to be transmitted on carrier frequency by amplitude shift keying. The smoothing control loop is provided for generating an increasing gate voltage for the second transistors on the basis of an increasing current ramp from a first minimum current value to a second maximum current value during a “0” to “1” data transition.

Abstract: An electronic device, e. g. a measuring transducer, has an interface circuit for communicating with and receiving power from a two-wire line, said interface circuit has a modulator connected to the two-wire line and responsive to an information signal for modulating the current in the two-wire line according to the information signal, and further has a controllable switching type DC-to-DC converter for extracting power for the electronic device from the two-wire line. To reduce energy losses, the DC-to-DC converter is designed to be controlled by said information signal and to perform the function of the modulation means.

Abstract: An internal operation of RF IC is adjusted so that the level of an RF transmitter signal is substantially stopped from rising, or made to descend in course of ramp-up of the RF transmitter signal. This adjustment is enabled by ramp-up adjustment data Last 4 symbols contained in preamble data precedent to real transmission data transmitted after completion of ramp-up. The ramp-up adjustment data and real transmission data are supplied from a baseband LSI. The RF transmitter signal contains phase and amplitude modulation components according to the EDGE system. RF IC includes phase and amplitude modulation control loops PM LP and AM LP. Ramp-up of RF power amplifiers PA1 and PA2 is performed by controlling the gain of the first variable amplifier MVGA included in the AM LP according to ramp information. Thus, unwanted radiation's level is reduced during ramp-up of the RF transmitter signal of the RF power amplifiers.