Abstract: A system configured to linearize a response of a nonlinear amplifier comprises a buffer to store a plurality of samples of an input signal to be amplified by the nonlinear amplifier. A self-receiver generates samples of an output signal of the nonlinear amplifier. A synchronization unit matches each sample of the output signal to a corresponding sample of the input signal stored in the buffer. A predistortion correction circuit generates a distortion correction function to be applied to the input signal to linearize the response of the nonlinear amplifier. The distortion correction function is generated based on a comparison of each matched sample of the output signal and corresponding sample of the input signal.

Abstract: An embodiment of the present invention provides an apparatus, comprising an RF matching network connected to at least one RF input port and at least one RF output port and including one or more voltage or current controlled variable reactive elements, a voltage detector connected to the at least one RF output port via a variable voltage divider to determine the voltage at the at least one RF output port and provide voltage information to a controller that controls a bias driving circuit which provides bias voltage or bias current to the RF matching network, and wherein the RF matching network is adapted to maximize RF power transferred from the at least one RF input port to the at least one RF output port by varying the voltage or current to the voltage or current controlled variable reactive elements to maximize the RF voltage at the at least one RF output port.

Abstract: A ferro-electric (FE) tunable antenna matching circuit is provided for a multi-band antenna. The tunable matching circuit is integrated with a diplexer on one substrate. The tunable matching circuit has a first and second inductor coupled to the antenna. The second inductor is couple to a first capacitor and a second capacitor. One side of the second capacitor forms an input/output port for connection to a duplexer. One or more of the matching circuit elements is a ferro-electric (FE) tunable component.

Abstract: A polar modulation transmitter offers a split architecture for determining amplitude modulation path delay of the transmitter and comprises a split supply modulation circuit and a split power amplifier circuit. The split supply modulation circuit includes a common supply input and is configured to receive a common amplitude-modulation signal at respective signal inputs and output first and second modulated supply signals responsive to the common amplitude-modulation signal.

Abstract: A method and apparatus of calibrating filtering of receive and transmit signals is disclosed. The method of calibrating filtering of a received signal includes injecting an LO signal. The injected LO signal is filtered by a tunable filter. The filtered signal is frequency down-converted with an equivalent LO signal. The frequency down-converted signal is sampled while tuning the filtering. A desired filter tuning is determined based upon the samples and a frequency of the LO signal. The method of calibrating filtering of a transmit signal includes injecting an LO signal to a transmitter. The LO signal is filtered by a tunable filter. The filtered signal is frequency down-converted with an equivalent LO signal. The frequency down-converted signal is sampled while tuning the filter. A desired filter tuning is determined based upon the samples and a frequency of the LO signal.

Abstract: An RFIC transmitter includes a digital transmit processing module, a digital to analog converter, a filter and gain module, an up-conversion module, a power amplifier, and a transmit signal strength module. The transmit signal strength module is coupled to generate a gain adjust signal based on a measure of transmit power of an outbound RF signal, wherein the transmit signal strength module provides the gain adjust signal to at least one of the digital transmitter processing module, the digital to analog converter, the filter and gain module, the up-conversion module, and the power amplifier.

Abstract: A radio channel simulator configured to read radio channel data describing a radio channel and user data including at least one user signal, and to simulate the radio channel using a FIR filter comprising one or more FIR blocks for filtering the user data read based on radio channel data in connection with the simulation. The radio channel simulator is configured to transfer at least one FIR block at a delay level depicting a radio channel delay during simulation.

Abstract: A transmitting apparatus includes a polar signal producing circuit which produces signals corresponding to the amplitude and the phase of a transmitting modulated wave from an input signal and multiplies the amplitude signal by the phase signal by a multiplying circuit to amplitude modulate a phase-modulated wave to produce a transmitting modulated wave and radiates this transmitting modulated wave as radio wave from an antenna. An amplitude/phase detecting circuit detects an amplitude signal and a phase signal from the input of the multiplying circuit and the input of a phase-modulated signal producing circuit.

Abstract: A method and apparatus for dynamically adjusting the impedance between a transmitter's power amplifier (PA) and antenna to efficiently transfer power from the PA to the antenna. The impedance between the PA and the antenna is adjusted based on power level measurements and/or PA direct current (DC) consumption measurements, depending on whether the PA is a linear PA or a switch-mode PA. In another embodiment, a hybrid PA including a first stage linear PA and a second stage switch-mode PA is implemented in a transmitter. The hybrid PA selectively connects the output of the first stage linear PA to one of the input of the second stage switch-mode PA and the output of the hybrid PA, depending on the output power level of the first stage linear PA, the output power level of the hybrid PA, or a requirement indicated by a transmit power control (TPC) command.

Abstract: A distortion correction circuit comprises memory that stores N samples of an input signal that occur at N different times, where N is an integer greater than two. A self-receiver samples an output signal that is generated by an RF power amplifier and that is based on said input signal. A synchronization unit selects one of said N samples by comparing said sampled output signal to said N samples. A predistortion unit generates a distortion correction function based on said selected one of said N samples and said output signal.

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: A comparator unit is used to compare an actual transmission time signal with a nominal transmission time signal and to produce a difference signal from the discrepancy, from which difference signal a correction signal is produced in a control unit. This correction signal is used to control a correction unit, which compresses or extends an applied input data signal, thus changing the phase angle of the output data signal so as to minimize the discrepancy between the transmission times. The discrepancy is corrected independently of the system clock, and the correction speed is set variably.

Abstract: Disclosed is a circuit and method for automatic tuning of a resonant circuit in a transceiver having a receiver and a transmitter that includes a power amplifier for driving the resonant circuit. During a transmit mode of the transceiver, a resonance voltage of the resonant circuit is compared to an input voltage signal to the power amplifier to determine an error signal that is converted into a control word. The control word drives an adjustable capacitance bank that is part of the resonant circuit. During a receive mode of the transceiver, the control word value is held constant to substantially maintain resonance of the resonant circuit during operation of the receiver.

Abstract: The invention relates to a method and device for performing channel simulation, the device comprising a set of channel simulation units (200 to 214) for simulating a radio channel, each unit comprising radio frequency parts (200A to 214A) and baseband parts (200B to 214B). In the solution of the invention, the baseband parts of several different units (200 to 214) are arranged to simulate the same channel.

Abstract: A tunable bandpass filter is provided that comprises a first shunt-connected ferroelectric (FE) tunable tank circuit having a first node to accept an input signal. A second shunt-connected FE tunable tank circuit has a second node to supply a bandpass filtered signal. A first capacitor is connected in series between the first and second nodes. In one aspect, the first tank circuit comprises a first resonator connected to the first node, and a fourth capacitor connected between the first resonator and a reference voltage. The fourth capacitor is a tunable FE capacitor. Typically, a fifth capacitor is connected between the first node and the reference voltage. Likewise, the second tank circuit comprises a second resonator connected to the second node, and a sixth (FE) capacitor connected between the second resonator and the reference voltage. A seventh capacitor is connected between the second node and the reference voltage.

Abstract: A transmitter includes a power amplifier which is capable of both linear and non-linear operation, controlled by first and second control loops. A power controller includes a capacitive component, and controls the gain of the power amplifier. A ramp generation circuit provides a control signal to the power controller. It includes a ROM which stores ramp data values based on samples of a predetermined ramp shape. The ramp shape is based on a generally regular profile C, for example a cos2 or cos4 function. The ramp shape also includes a boost portion BAP, which enhances the ramp data values before the beginning of the generally regular profile C. The boost portion BAP causes the capacitor in the feedback loop of the relevant control loop to become fully charged more rapidly, which produces a corresponding increase in the output power of the power amplifier shortly after the generally regular profile C is applied.

Abstract: As disclosed herein, a microelectronic circuit and method are provided for improving signal integrity at a transmission line. The circuit includes a programmably adjustable impedance matching circuit which is coupled to a transmission line which includes a programmably adjustable inductive element. The programmably adjustable impedance matching circuit is desirably provided on the same chip as a receiver or transmitter to which the transmission line is coupled, or alternatively, on an element packaged together with the chip that includes the receiver or transmitter. The impedance of the programmably adjustable impedance matching circuit is adjustable in response to control input to improve signal integrity at the transmission line.

Abstract: On-chip calibration signal generation circuitry is disclosed for filter tuning for radio-frequency communications and associated methods. On-chip circuitry generates a calibration signal that is used to help set a tuning control signal that is received by a tunable front-end filter. In one embodiment, local oscillator (LO) generation circuitry is used to generate the calibration signal. In operation of this embodiment, the LO generation circuitry is tuned to the desired receive channel, or to a frequency at some offset value from the desired receive channel, and the output of the LO generation circuitry is then used as a calibration input signal for a tunable front-end filter. This calibration signal is passed through the receive path circuitry, and the resulting signal is then analyzed to help set a tuning control signal for the tunable front-end filter.

Abstract: A transmitter is provided which includes a transmitting circuit that does not require a high-performance low noise VCO restricting cost reduction thereof and that can reduce the number of parts without requiring an RF filter. A direct conversion that does not require a transmission VCO is applied to the transmitting circuit. In order to achieve noise reduction in a receiving band, low-pass filters are provided a IQ input sections of a modulator that converts IQ signals into RF signals. In comparison with a conventional transmitter using offset PLL, an external VCO required in addition to an RF integrated circuit, a power amplifier, and a front end circuit is reduced. Even in current transistor performance, by using a filter having rapid waveform characteristics such as a SAW more inexpensive than the VCO, or the like, it is possible to provide a GSM/GSM 1800/GSM1900 triple band transmitter.

Abstract: The invention relates to methods for determining the separate radio frequency gains for carriers in a multi-carrier transmitter of a radio transmission unit of a radio communications system. In order to enable a simple and accurate estimation of the gains, it is proposed to determine the individual gains (G1–GN) of the different carriers mathematically from different sets of powers (REF1–REFN) at some point in each single carrier unit and the corresponding total output powers of the transmitter. Alternatively, the relation of the powers of the different carriers to each other is determined just before the carriers are combined to a single multi-carrier signal. This relation is used for determining the contribution of the different carriers to the transmission power of the multi-carrier signal and for therefrom determining the radio frequency gains for the different carriers. The invention equally relates to corresponding radio transmission units and modules of such radio transmission units.

Abstract: Automatic gain control (AGC) functionality is distributed within a transmitter chain. A controller manages two or more variable gain amplifiers to achieve the desired result.

Abstract: An automatic matching and tuning unit (AMTU), which connects the output from a low or medium frequency, high power radio transmitter, which requires a 50 ohm terminating impedance, to an antenna with an input impedance comprising low resistance in series with a high capacitive reactance. Sensors measure the phase angle between the input current and voltage. The inductance of a series connected loading coil is continuously varied to resonate the antenna capacitance. The resulting input resistance is transformed to 50 ohms using a matching transformer and pair of resonant, mutually coupled coils with adjustable mutual coupling. Sensors measure the input resistance and continuously adjust the mutual coupling coefficient to maintain the required 50 ohm input impedance. Sensors measure the antenna current and vary the transmitter power level to keep it constant. A microcontroller processes all of the sensor outputs and provides serial communication with the transmitter.

Abstract: The present invention relates to a method and a system for tuning a radio filter. The radio filter comprises at least one resonator module, each of said at least one resonator module having a tuning mechanism, a filter input connection, a filter output connection. High frequency broad band input and output signals of each of said at least one resonator module are sensed and processed to tune the radio filter. The processing of the sensed input and output signals includes processing in a low-frequency range.

Abstract: A wireless remote unit is operable to demodulate signals received over a plurality of different bands, such as the FM broadcast band, and one or more higher frequency bands. The various bands have different channels and the selection of the band and the channel is accomplished by control signals received by the receiver. The control signal can carry menu information in one direction to the user and can carry user data, including the identity of the user, in the other direction. There can be multiple transmitters, wherein each transmitter sends information on a different channel within a band, and tunes remote units to a particular transmitter based upon proximity to that transmitter. The transmitter is capable of displaying visual data. The visual data includes a predetermined number of advertisements to be displayed during a user session, prompted either by a user logging onto the system, or by the system's detection of a user's presence.

Abstract: Disclosed is a circuit and method for continuous automatic tuning of a resonant circuit. A resonance voltage of the resonant circuit is phase shifted by a predetermined phase shift ? degrees and an input voltage signal to a power amplifier driving the resonant circuit is phase shifted by ?±90 degrees to place the signals in quadrature. The phase shifted signals are mixed to obtain a error signal. The error signal is compared to a predetermined voltage range in order to generate control signals for a control word generator, such as an up-down counter. The control word generator produces a control word that drives a capacitance bank that is part of the resonant circuit. The present invention continuously automatically adjusts the capacitance of the capacitance bank to tune the resonant circuit.

Abstract: A radio has a tunable bandpass filter that is tuned by apparatus within the radio. A reference generator generates a reference signal for use in tuning the tunable bandpass filter. The tunable bandpass filter receives the reference signal and provides a filter output signal. A digital signal processing and control processor is connected to the tunable bandpass filter to receive the filter output signal. The digital signal processing and control processor has a phase comparison function that provides a phase error metric from the filter output signal. The digital signal processing and control processor tunes the tunable bandpass filter to provide a desired phase error metric signal thereby tuning the tunable bandpass filter to the desired center frequency. The digital signal processing and control processor stores tunable filter parameters for the desired center frequency. The tuning process may be repeated for several desired center frequencies of the tunable bandpass filter.

Abstract: The present invention relates to a method for tuning a radio filter. The filter comprises an input connection, an output connection and at least two resonator modules coupled in cascade, each having a tuning mechanism and a probe. A first resonator module is connected to the input connection and a final resonator module is connected to the output connection. The filter is adapted to receive at least one signal within a frequency range. The method comprises essentially two steps: coarse tuning, which is dependent on the frequency content of the received signal(s), and fine tuning, which is dependent on a calculated deviation between a set value vector and a measured signal parameter vector. A relationship between the set value vector and the signal parameter vector is established for calculating the deviation. The invention also relates to a radio filter and a system comprising such a radio filter.

Abstract: A high-frequency coupler for extracting a secondary signal representative of a main signal carried by a conductive line, including two series-coupled, respectively high-pass and low-pass, filters, and the input of which is intended to be connected to said line while its output is intended to provide the secondary signal, the filters being sized so that the sum of their respective attenuations is substantially constant over the coupler passband, and so that their respective cut-off frequencies are in said passband.

Abstract: The present invention relates to a method for tuning a radio filter. The filter comprises an input connection, an output connection and at least two resonator modules coupled in cascade, each having a running mechanism and a probe. A first resonator module is connected to the input connection and a final resonator module is connected to the output connection. The filter is adapted to receive at least one signal within a frequency range. The method comprises essentially two steps: coarse tuning, which is dependent on the frequency content of the received signal(s), and fine tuning, which is dependent on a calculated deviation between a set value vector and a measured signal parameter vector. A relationship between the set value vector and the signal parameter vector is established for calculating the deviation. The invention also relates to a radio filter and a system comprising such a radio filter.

Abstract: The present invention provides a transceiver apparatus that permits miniaturization even when the antenna thereof is an unbalanced circuit and the transmitter circuit section and receiver circuit section thereof are balanced circuits. The transceiver apparatus is constituted comprising: a semiconductor integrated circuit device that mounts on the same semiconductor chip a balanced receiver circuit 41 for receiving a received signal as a differential input and balanced transmitter circuit 52 for outputting a transmitted signal as a differential output, and that has at least two terminals 71,72 connected to connecting nodes that connect the balanced receiver circuit 41 and the balanced transmitter circuit 52; first and second capacitors C2,C3 connected to the terminals 71, 72 respectively; an external inductor L1 connected to the first and second capacitors C2, C3; a band pass filter 2 and an antenna 1 coupled to the first capacitor C2; and a third capacitor C1 connected to the second capacitor C3.

Abstract: The present invention provides a communication terminal that enables precise communications with optimum receive sensitivity at any time regardless of any change in peripheral environments of an antenna thereof. The communication terminal including means for transmitting and receiving radio waves is provided with a training mechanism for enabling the communication terminal itself to conduct training mode for tuning receive sensitivity, and switching mechanism for switching between normal communication mode and the training mode. The communication terminal is particularly useful as a communication terminal for automobile in the Intelligent Transport System or the like.

Abstract: A receiver receives an electromagnetic signal via an antenna mounted on an antenna mast. A signal evaluator determines or measures a signal quality level associated with the received electromagnetic signal. The signal quality compares the determined signal quality level to a threshold minimum signal quality level. A current elevational position of the antenna mast is detected or tracked. The antenna mast is raised to a greater height than the current elevational position if the compared signal quality level is less than the threshold minimum signal quality level and if the current elevational position is less than a maximum height of the antenna mast.

Abstract: Remotely controllable actuators are provided to alter the cavity size of bandpass cavity filters to alter the bandpass characteristics. In one embodiment, a stepper motor is used to provide lateral movement of a tuning plate to alter the size of the cavity. The neck of the cavity is also changed in length through the use of a tuning motor. A feedback loop is used to provide fine tuning of the length of the neck in response to changes due to temperature and vibration to offer maximum propagation of the signal to be transmitted. A coupling tuner is used to adjust to the resulting change in Q to the cavity. A tuning processor is used to receive signals from a remote location identifying the desired characteristics of the filter.

Abstract: A method and apparatus for correcting for a phase shift between a transmitter and receiver comprising the steps of: a) transmitting a signal from a transmitter (14); b) receiving the transmitted signal (16) at a receiver (20); c) comparing the received signal (17) to a reference signal; d) if a difference between the reference signal and the received signal (17) is greater than a predetermined value go to step e), if not go to step g); e) adjusting a frequency of the transmitted signal (16); f) go to step a); and g) calibration complete.

Abstract: An information processing apparatus, comprising a wireless module which performs wireless communication, the wireless module being detachably mounted, a frequency circuit which generates a plurality of frequencies, the plurality of frequencies serve as operation frequencies, a wireless communication frequency band determination unit which determines a wireless communication frequency band used by the wireless module for wireless communication, and a selection unit which selects a frequency that does not interfere with the wireless communication frequency band.

Abstract: A ferro-electric tunable duplexer is provided, integrated with one or more of the following parts: a power amplifier, an isolator, a diplexer, a low noise amplifier and an antenna matching circuit. More specifically, in addition to adding F-E tunability, one or more of the above components is integrated with the duplexer on one substrate. The components are integrated on one substrate either by placing each component, with the appropriate matching circuit directly on the substrate, or by direct fabrication of the component and matching circuit into or onto the substrate.

Abstract: Control circuitry for a transmitter comprises means for receiving a first plurality of signals at different frequencies at the same time; means for generating a second plurality of signals; means for reducing the frequency of the first plurality of signals by mixing the first plurality of signals with said second plurality of signals to provide a series of samples of said first plurality of signals, wherein each of said samples is separated in time; and means for adjusting a characteristic of signals to be transmitted dependent upon said samples.

Abstract: There is disclosed a system for tuning a tunable narrowband cavity filter in a base station transmitter of a wireless network. The radio frequency (RF) transmitter comprises: 1) modulation circuitry for modulating an input baseband signal to produce a first RF signal; 2) amplification circuitry for amplifying the first RF signal; 3) a tunable narrowband cavity filter for filtering the amplified first RF signal and transmitting the filtered and amplified first RF signal to an antenna coupled to an output of the tunable narrowband cavity filter; and 4) a system for tuning the tunable narrowband cavity filter.

Abstract: An A/B class output stage of a signal treating circuit, such as for example a mobile telephone, a radio car kit, other portable equipment, etc. treats a signal. The A/B class output stage drives a load with the signal as treated by the signal treating circuit. The output stage can be connected to one of more than one supply voltages as a function of a voltage value of the signal. The signal treating circuit comprises a D/A converter circuit and a non-linear operating circuit between an input of the signal treating circuit and the D/A converter. Above a certain signal value a change in supply voltage is made. Distortions in an output signal resulting from such a change are prevented by having the non-linear operating circuit generate a jump in DC level at an output of the output stage or raise a value of the signal at a non-clipping one of two output terminals with an extra amount that compensates for the clipping at a clipping one of the two output terminals.

Abstract: The present invention relates to a method and a system for tuning a radio filter. The radio filter comprises at least one resonator module, each of said at least one resonator module having a tuning mechanism, a filter input connection, a filter output connection. High frequency broad band input and output signals of each of said at least one resonator module are sensed and processed to tune the radio filter. The processing of the sensed input and output signals includes processing in a low-frequency range.

Abstract: A search and rescue beacon includes a main transmitter transmitting a Cospas-Sarsat signal at a main frequency and an auxiliary homing transmitter transmitting a homing signal at a homing frequency close to the main frequency. Advantageously both the Cospas-Sarsat signal and the homing signal are generated by a single synthesizer switching between a main Cospas-Sarsat burst transmission and a continuous homing frequency transmission of the homing signal. The Cospas-Sarsat signal is advantageously transmitted at a higher power than the homing signal. The single synthesizer may use a single amplifier chain. The single synthesizer and amplifier chain may use a single antenna.

Abstract: An optimal operating point of an envelope tracking amplification system that includes a radio frequency (RF) power amplifier having an RF amplifying element is determined based on an application to the RF power amplifier of a supply voltage that is less than the rated voltage of the RF amplifying element.

Abstract: A method for improving the use of a transmission spectrum in a multi-sector wireless communication system includes generating a first signal, processing a first signal with a first Auto Tune Combiner, transmitting the first signal on an antenna associated with a first sector, sampling the first signal with a radio frequency test device, generating a second signal, processing the second signal with a second Auto Tune Combiner, transmitting the second signal on an antenna associated with a second sector, and sampling the second signal with the radio frequency test device.

Abstract: A radio-frequency power amplification circuit is equipped with a transistor and a stabilization circuit that is provided upstream of the transistor. The stabilization circuit is equipped with a series resistor one end of which is connected to the transistor and the other end of which is connected to an input terminal, a resistance element one end of which is connected to the other end of the series resistor, and a short stub one end of which is connected to the other end of the resistance element 22 and the other end of which is grounded via a capacitance element.

Abstract: A system for managing return channel bandwidth in a two-way satellite communication network is disclosed. A plurality of transceivers are configured to transmit backlog information over a return channel via a satellite. The backlog information specifies an amount of queued traffic for the respective transceivers. A hub is configured to receive the backlog information and to allocate a predetermined amount of return channel bandwidth to each of the plurality of transceivers. The hub determines whether additional return channel bandwidth is available to accommodate a remaining backlog such that a bandwidth allocation amount is set to a level associated with one of the plurality of transceivers having the largest backlog. The hub selectively identifies a transceiver among the plurality of transceivers having a next largest backlog based upon the determined available return channel bandwidth.

Abstract: A signal having a substantially uniform spectral distribution, e.g., a flat noise signal such as a signal ground, is provided at the input of a bandpass filter such as an IF filter of a receiver circuit, to thereby produce an output signal at the output of the bandpass filter. The output signal is processed in a limiter to produce a limited signal. An average frequency of the limited signal is determined, and the bandpass filter is adjusted based on the determined average frequency. According to one embodiment of the present invention, the bandpass filter comprises a Gm-C filter having a transconductance, and the filter is adjusted by adjusting the transconductance of the Gm-C filter based on the determined average frequency. According to another aspect of the present invention, a desired center frequency for the bandpass filter is identified. A resolution and a desired confidence interval are also identified.

Abstract: The invention relates to a data transmission method and a radio system, which comprises a plurality of transceivers (100, 108 to 112) that are arranged to intercommunicate by using a plurality of predetermined radio frequency channels, and in which radio system a maximum value is determined for the amount of interference caused to adjacent frequency channels by the transmitter. In the solution in accordance with the invention, for reducing the power consumption of the transmitters, the transceivers of the system are arranged to transmit on different radio frequency channels, using different maximum values of adjacent channel interference.

Abstract: Systems and methods for optimizing the efficiency of each of a plurality of power amplifiers that amplify a corresponding one of a plurality of radio frequency signals for transmission by a corresponding one of a plurality of antennas. Using transmit beamforming, the power of each amplified signal output by the power amplifiers may not be the same for all the power amplifiers, and may vary with changes in the communication channel between the transmitting device and receiving device. Each of the plurality of power amplifiers is controlled to operate with one or more operating parameters that optimize the efficiency for an output power level of corresponding ones of the radio frequency signals. By adjusting one or more operating parameters of each power amplifier according to changing requirements (e.g., the destination device and channel conditions), the efficiency of each power amplifier can be optimized.

Abstract: A tuning arrangement tunes a resonance module for wireless applications, e.g., wireless communication for a base station for mobile telephony system. The input and the output power signals of the resonance module are derived and information bearing parts of the derived power signals are divided with each other to produce a ratio. The resonance module is tuned until the ratio reaches a minimum value.

Abstract: A monolithic AM transmitter is disclosed. An external antenna forms part of a resonance network so that the antenna resonance point is automatically tuned to the transmit frequency. This provides flexibility with no added cost to the transmitter. Additionally, components of the transmitter can be formed on a single monolithic integrated circuit.