Abstract: A monolithic integrated circuit (IC), and method of manufacturing same, that includes all RF front end or transceiver elements for a portable communication device, including a power amplifier (PA), a matching, coupling and filtering network, and an antenna switch to couple the conditioned PA signal to an antenna. An output signal sensor senses at least a voltage amplitude of the signal switched by the antenna switch, and signals a PA control circuit to limit PA output power in response to excessive values of sensed output. Preferred fabrication techniques include stacking multiple FETs to form switching devices. An iClass PA architecture is described that dissipatively terminates unwanted harmonics of the PA output signal. A preferred embodiment of the RF transceiver IC includes two distinct PA circuits, two distinct receive signal amplifier circuits, and a four-way antenna switch to selectably couple a single antenna connection to any one of the four circuits.

Abstract: A single ended highly linear power amplifier includes a component, a 1st transistor pair, and a 2nd transistor pair. The 1st and 2nd transistor pairs are coupled in series with the component, which may be a resistor, inductor and/or linearly loaded transistor, where the node coupling the component to the 1st and 2nd transistor pairs provides the output of the single-ended highly linear power amplifier. The 1st transistors of the 1st and 2nd transistor pairs are coupled to receive an input signal. The 2nd transistors of the 1st and 2nd transistor pairs are each coupled to receive a separate enable signal. The transistor pairs are enabled via their corresponding enable signal to change the gain of the power amplifier with negligible effects on the linearity of the power amplifier. A differential power amplifier includes the single ended power amplifier and a complimentary mirror image of the single ended power amplifier.

Abstract: A receiver comprises a first Variable Gain Amplifier (VGA) that amplifies an input signal in accordance with a first gain to produce a first amplified signal. The first gain is controlled based on the first amplified signal. The receiver includes a second VGA that produces a second amplified signal responsive to the first amplified signal. The second VGA has a second gain controlled based on the second amplified signal.

Abstract: A programmable multi-stage amplifier includes a 1st programmable amplifier, a 2nd programmable amplifier, and a control module. The 1st and 2nd programmable amplifiers are coupled in series to amplify an input signal. Each of the 1st and 2nd programmable amplifiers is operably coupled to receive independent gain control signals from the control module. The control module generates the gain control signals by determining the overall gain desired for the programmable multi-stage amplifier and a corresponding gain for each of the 1st and 2nd programmable amplifiers. The factors in which the control module makes this determination are based on an optimization of at least one of the power level of the programmable multi-stage amplifier, the noise factor for the programmable multi-stage amplifier, and/or linearity of the programmable multi-stage amplifier.

Abstract: The present invention includes a transceiver and a method of operating the same that includes in the transmitter a power control circuit that operates on an analog differential signal containing data packets individually. The power control circuit initially transmits a series of data symbols with known values, periodically strobes the transceiver system for correct power levels and incrementally increases the power level of the transceiver until the optimal gain is reached, without exceeding the maximum output power.

Abstract: A circuit for regulating the power provided to a load connected to an output of a power amplifier. The circuit includes an amplitude detector that outputs a voltage corresponding to the amplitude of the signal outputted by the power amplifier. This output voltage is a function of the impedance of the load. Thus, when the impedance of the load changes, the output voltage also changes. Given a constant current into the load, it is the load impedance that determines the power delivered to the load. Therefore, because the output voltage reflects changes in the impedance of the load, the output voltage can be used by a regulator circuit to maintain a constant output power, regardless of changes in the impedance of the load.

Abstract: A low-noise switching voltage regulator for supplying a voltage to a radio frequency (RF) power amplifier is disclosed. In one embodiment, the invention can be conceptualized as a power amplifier supply circuit, comprising a pair of oppositely polarized semiconductor switches, and a data formatter configured to supply a data stream having a voltage transition on at least every other bit to each of the pair of oppositely polarized semiconductor switches.

Abstract: The invention relates to a transmitter which comprises a modulator providing a phase-modulated constant-envelope radio-frequency signal, and to a method of controlling the power level of a signal output by such a transmitter. In order to enable a power control over a large power range, it is proposed that a provided phase-modulated constant-envelope radio-frequency signal is divided into two identical signals for the power control. A first control arrangement then controls the output power for higher power levels by controlling amplifications applied to the two signals. A second control arrangement controls the output power for lower power levels by controlling phase shifts applied to the two signals. The processed signals are then combined and provided as a power controlled output signal.

Abstract: A wireless communication apparatus includes a variable power amplifier (19) and a power amplifier (20). A variable power amplifier control unit (24) controls the gain of the variable power amplifier (19) for controlling transmission power of the own apparatus. At this time, a condition change detecting unit (28) detects changes in conditions of the own station and a counter station. Based upon the detected condition changes, a transmission power control bit controlling unit (26) and a transmission power control period controlling unit (27) change a control period of a transmission power control bit and a transmission power control range. This transmission power control bit is inserted into a transmission signal, then, the transmission signal is transmitted to the counter station. The condition changes are detected based upon reception power, transmission power, the transmission power control bit, a change amount of control conditions, and a change speed of the control conditions.

Abstract: The present invention, generally speaking, provides methods and apparatus for producing an amplitude modulated communications signal, in which a constant-envelope carrier signal is modified in response to a power control signal to produce a modified constant-envelope carrier signal. The modified constant-envelope carrier signal is amplified in response to an amplitude modulation signal to produce a communications signal having amplitude modulation and having an average output power proportional to a signal level of the modified constant-envelope carrier signal. This manner of operation allows wide dynamic range of average output power to be achieved. Because amplitude modulation is applied after amplitude varying circuitry used to produce the modified constant-envelope carrier signal, the amplitude modulation is unaffected by possible non-linearities of such circuitry.

Abstract: A booster system in a cellular phone base station comprises a plurality of power amplifiers, each of which configured to receive a signal provided by a corresponding transceiver unit that is coupled to said booster system. A hybrid combiner is coupled to the power amplifiers, and is configured to combine the signals generated by each of the power amplifiers. A VSWR sensor is configured to sense a voltage standing wave ratio at an output port of the booster system. Furthermore, a radio frequency relay is provided, which is configured to receive signals provided by the transceiver units. The radio frequency relay is triggered in response to an indication signal based on either a failure in the booster system or a failure in the signal path following the booster system.

Abstract: The present invention, generally speaking, provides methods and apparatus for producing an amplitude modulated communications signal, in which a constant-envelope carrier signal is modified in response to a power control signal to produce a modified constant-envelope carrier signal. The modified constant-envelope carrier signal is amplified in response to an amplitude modulation signal to produce a communications signal having amplitude modulation and having an average output power proportional to a signal level of the modified constant-envelope carrier signal. This manner of operation allows wide dynamic range of average output power to be achieved. Because amplitude modulation is applied after amplitude varying circuitry used to produce the modified constant-envelope carrier signal, the amplitude modulation is unaffected by possible non-linearities of such circuitry.

Abstract: An antenna switch including a transmit connection for inputting a radio frequency signal, an antenna connection for connection to an antenna for transmitting the radio frequency signal, and a signal path between transmit connection and the antenna connection including at least one transmit transistor controllable to connect selectively the transmit connection to the antenna connection so as to transfer the radio frequency signal from the transmit connection to the antenna connection wherein the transmit transistor is arranged so as to provide a stage of amplification to the radio frequency signal.

Abstract: A radio power output amplifier comprises a balanced radio power output that differentially drives a dipole antenna or other balanced load. One half of the differential power output drives one side of the antenna from ground to the maximum positive rail, while the other half of the differential power output drives the opposite side of the antenna from the maximum positive rail to ground. The result is a voltage swing across the antenna that is twice that which would occur if a single ended output was driving an unbalanced load. Since the power output is the square of the voltage divided by the load impedance, the result is four times the power output.

Abstract: An embodiment of the invention is a system for signal processing in preparation for wireless transmission, the wireless transmission being from a portable wireless communication device and including use of a power amplifier having nonlinear characteristics. The system includes memory for storing digitally-indexed information. The digitally-indexed information models nonlinear characteristics of the power amplifier, and the digitally-indexed information is stored prior to processing of a first signal that reflects information to be communicated. The system further includes first logic, configured to accept the first signal and to retrieve, based on the first signal, a portion of the digitally-indexed information stored in the memory, and second logic, configured to generate a second signal based on the portion of the digitally-accessed information and on the first signal.

Abstract: An apparatus for power controlling in a transmitter for detecting the output power without using a power coupler includes a plurality of stage amplifiers, a plurality of matching circuits, at least one power detector, and a bias control circuit. The stage amplifiers receive an emission signal and amplify the power thereof. The matching circuits are connected between the stage amplifiers for matching with the stage amplifiers, respectively. The power detector detects the power of the stage amplifiers and generates detection signals, respectively. The bias control circuit receives the detection signals of the power detector, thereby generating a bias of each of the stage amplifiers in order to optimize the efficiency of each of the stage amplifiers according to the magnitude of the power of each of the stage amplifiers.

Abstract: A transmitter into which a modulated signal (TX) is fed, the transmitter comprising an adjustable amplifier (1) for adjusting transmission power level, the modulated signal (TX) being fed into to the input of the amplifier (1), an amplification branch (11) arranged after the adjustable amplifier (1) on the signal path, the amplification branch comprising a power amplifier (3) for further amplifying the transmission power level, and at least one filter (27, 28) arranged after the power amplifier (3) on the signal path for filtering the frequency band to be transmitted. The transmitter further comprises an antenna (9) after the amplification branch (11) on the signal path for transmitting signals. The transmitted is characterized by a bypass branch (10) which operatively couples the output of the adjustable amplifier (1) and the antenna (9) and is used for bypassing the amplification branch (11) and connecting signals to be transmitted at low transmission power levels directly to the antenna (9).

Abstract: An RF power control system including a watchdog circuit for monitoring the power level of an RF signal about to be transmitted by an antenna and for monitoring the antenna beam scan angle and for adjusting and/or interrupting the RF signal in the event that the power level of the RF signal or the scan angle of the antenna beam exceed predetermined thresholds. The use of the watchdog circuit eliminates the need for stringent safety certification of a number of other subcomponents of the system and therefore significantly reduces the cost and time associated with obtaining regulatory certification of the system. In preferred forms, the watchdog circuit includes an enable input for allowing the watchdog circuit to be completely deactivated, and therefore transparent to the RF signal being generated.

Abstract: An integrated detector circuit (20) includes first and second gain stages (GS1, GS2). The first gain stage has an input (82) that monitors a high frequency signal (VRFDET) for routing a first detection current (IS1) to a node (60). The second gain stage includes a first current source (PF1) that supplies a bias current (IMAX1) indicative of a predefined amplitude of the high frequency signal. An input of the second gain stage monitors the high frequency signal to route a portion of the bias current to the node as a second detection current (IS2), which is limited to the bias current when the high frequency signal is greater than the predefined amplitude to compensate for a nonlinearity in a transconductance of the second gain stage.

Abstract: A reduction of the overall power loss in a resonance circuit is achieved by having excitation occur within excitation periods (Tex) of resonation periods (Tfre), during which the resonance circuit is in a free running resonance mode, the excitation periods being smaller than the resonation periods, to define an excitation duty cycle (Tex/Tcar) relative to the period of a carrier signal (Tcar) of less than 0.5. Preferably the resonance frequency (fres) of the resonance circuit is higher than the carrier frequency (fcar) of the modulated high frequency carrier signal over a resonance frequency detuning rate (dfres), defined by the frequency deviation of the resonance frequency from the carrier frequency relative to the carrier frequency (fres/fear-1), substantially at most corresponding to half the excitation duty cycle.

Abstract: A cellular telephone receives a first communication signal from a cell-site Station and transmits a second communication signal to the cell-site station. The cellular telephone includes an antenna, a duplexer, receiver, an encoder/decoder apparatus, an acoustic transducer, a transmitter and a controller. The receiver is connected to the antenna through the duplexer. The receiver converts the first communication signal into a voice signal code, and outputs a signal indicating an intensity of the first communication signal. The transmitter is connected to the encoder/decoder apparatus and to the antenna through the duplexer. The receiver converts the input voice code Signal from the encoder/decoder apparatus into the second communication signal. The controller is connected to the receiver and the transmitter. The controller controls amplitude of the transmitter corresponding to said intensity of the first communication signal.

Abstract: The invention provides a signal processing semiconductor integrated circuit of the direct conversion system, which includes a dummy amplifier having the same circuit configuration as a low noise amplifier being the first stage amplifier, in which the DC offset calibrations on the subsequent stage amplifiers are carried out during shifting into the reception mode in a state that the low noise amplifier is deactivated and the dummy amplifier is activated. Thereby, the invention achieves to suppress generation of the DC offsets resulting from the leakage noises of the local oscillator during shifting into the reception mode, and to enhance the reception sensitivity.

Abstract: A booster amplifier that can be coupled to virtually any cellular telephone handset is provided for use with virtually any cellular communications network. The power output of the booster amplifier is dynamically controlled based upon signals received from the handset to improve the quality and range of communications between the handset and the base stations of the cellular network without interfering with normal communications between the cellular network and other handsets.

Abstract: A bias circuit according to the present invention includes a monitoring circuit having a second FET and a resistance connected to a drain of the second FET for monitoring a drain current of a first FET to be supplied with a gate bias; a differential circuit including a third FET having a gate supplied with a reference voltage, a fourth FET having a gate connected to the drain of the second FET, sources of the third FET and the fourth FET being connected to a common point, and resistances connected to drains of the third FET and the fourth FET, respectively; and a fifth FET having a drain connected to the common source of the third FET and the fourth FET; wherein a drain voltage of the third FET is fed back to gates of the first FET and the second FET, and a drain voltage of the fourth FET is fed back to a gate of the fifth FET.

Abstract: A high frequency circuit capable of realizing a power amplifier with a wide dynamic range in which it is hard to degrade the power addition efficiency at low output is formed by using a high output amplifier cell block configured to amplify input signals at a time of high output power, in which a DC power source voltage is supplied in parallel to first amplifier cells that are connected in parallel AC-wise with respect to input/output signals, and a low output amplifier cell block configured to amplify input signals at a time of low output power, in which a DC power source voltage is supplied in series to second amplifier cells that are connected in parallel AC-wise with respect to input/output signals.

Abstract: A radio receiver has a low noise amplifier. The low noise amplifier is enabled. If a predicted level of interference is expected to produce an acceptable bit error rate or other signal error measurement, the low noise amplifier is set to a “low” linearity level. If the predicted level of interference is not expected to be acceptable, the low noise amplifier is adjusted to a “high” level of linearity. The level of linearity required is determined by checking one or more prediction criteria: the mobile station's current operating mode, the strength of a received signal, the strength of a signal transmitted by the mobile station, the current level of interference, an acceptable level of interference, and whether the low noise amplifier is enabled or bypassed. Each of the prediction criteria may not be weighted equally. The determination is repeated as the prediction criteria change.

Abstract: An amplifier comprises a first amplifier circuit which amplifies a first signal to output an amplified first signal, a circuit which outputs a second signal corresponding to a difference between the first signal and the amplified first signal, a second amplifier circuit which amplifies the second signal to output an amplified second signal, a combine circuit which outputs an amplified signal by combining the amplified second signal with the amplified first signal, and a controller which controls a supply of a power to the first amplifier circuit and the second amplifier circuit and has a first mode to supply the power to the second amplifier circuit without supplying the power to the first amplifier circuit.

Abstract: A method and arrangement for forming an address for use in signal predistortion. The arrangement is used to form a corrector table address employed in the signal predistortion to compensate for signal distortions. The signal distortions are compensated for using corrector coefficients that are placed in the corrector table and retrieved from the table on the basis of the address. The arrangement includes calculation means that, on the basis of the received signal, calculate a result corresponding to the squaring of a received signal. The arrangement further comprises summing means that, if required, sum up the results corresponding to the squaring, the sum forming a base address. The arrangement further comprises error correction means that correct the calculated base address by means of an address correction value.

Abstract: An error amplifier circuit reduces distortion in an amplified signal by reflecting a feedback signal into the amplified signal using an output transformer. A first amplifier generates a reference signal corresponding to the input signal from which the amplifier output signal is derived. This reference signal represents the desired waveform for the amplified signal. An error sense element generates an error signal based on the difference between the reference and amplified signals. The error sense element preferably imparts high common-mode rejection to the error signal. A second amplifier generates the feedback signal based on amplifying the error signal, and an output transformer generates a compensated amplified signal by coupling the feedback signal into the amplified signal. The output transformer increases the reflected load impedance seen by the error amplifier, thus relieving it from driving the feedback signal into the potentially low load impedance driven by the compensated amplified signal.

Abstract: In a power control circuit according to the present invention, a circuit for making a desired response at a specific level is stationarily fed with a signal at the specific level so that the resultant level deviation is automatically corrected at a stage subsequent to the circuit. Besides, a transmitter according to the present invention is configured with provided a modulator as the above-described circuit. In a system or equipment according to those inventions, without its configuration being changed drastically, the desired characteristics and performances are kept with high accuracy, the cost for the manufacture, maintenance, and running is reduced, and the overall reliability is improved.

Abstract: An amplifier provides two or more selectively enabled amplifier segments allowing a source signal to be amplified with a selectable output power. A bias circuit responsive to a bias control signal enables selectable combinations of one or more amplifier segments, thus allowing selection of a desired output power. Selecting a desired output signal power via the bias control signal corresponds to selecting an overall amplifier quiescent current that decreases with decreasing output signal power. Thus, the amplifier permits a controlling system, such as a mobile terminal (e.g., cellular telephone) to amplify a transmit signal with a selectable transmit signal output power and corresponding level of amplifier quiescent power consumption. Preferably, each segment comprises one or more transistor amplification stages which, when enabled by the bias circuit, are biased to permit maximum power linear amplification for the transmit signal.

Abstract: A radio communication apparatus including at the transmitter-side output stage a high-frequency power amplifier module that has incorporated therein a single-stage amplifier using one multi-finger type heterojunction bipolar transistor (HBT) or a multi-stage amplifier using a plurality of HBTs sequentially connected in cascade, and at the output end an antenna connected to the high-frequency power amplifier module, wherein first capacitors and first resistors are inserted in series between the input terminal of the high-frequency power amplifier module and the control fingers of the HBT, and second resistors are inserted between the control terminal of the high-frequency power amplifier module and the control fingers of the HBT and connected to the nodes of the first resistors and the first capacitors.

Abstract: Disclosed is a direct conversion type transmitter or transceiver circuit suitable for a mobile communication device which corresponds to broad signal output level variable width to be required by W-CDMA, which does not necessitate any high-performance low noise VCO and RF filter, capable of reducing a number of components and the cost. In the input portion of an orthogonal modulator composed of a divider, mixers, and a common load, there are provided variable attenuators. If an input signal level of the orthogonal modulator within the transmitter circuit lowers, this variable attenuator circuit is operated so as to lower the bias of the orthogonal modulator to reduce the amount of occurrence of carrier leak, and to prevent the signal during low output level and carrier leak ratio from being deteriorated.

Abstract: A power amplifying apparatus for a mobile phone is provided. In the power amplifying apparatus, a power amplifier uses a transistor as a power amplifying device, and a non-volatile memory pre-records the static characteristic measurement data of the transistor. A DC bias current of the transistor is controlled according to transmission power of the power amplifier referring to the static characteristic measurement data, by changing a gate voltage of the transistor, by changing a drain voltage of the transistor with the gate voltage fixed, or by changing both the gate voltage and the drain voltage.

Abstract: A portable mobile terminal or a transmission unit, applicable to multiplex radiocommunication systems including a CDMA, comprises a modulating section for modulating a transmission signal by using a spectrum spread system, an amplifying section for amplifying the modulated transmission signal to a needed transmission power, a plurality of variable gain units provided between the modulating section and the amplifying section to be connected in series to each other to provide an ability of changing a gain of the transmission signal modulated by the modulating section, and respectively having gain-to-phase characteristics set to cancel a phase variation of the transmission signal to the entire gain variation, and a control section for controlling a gain of each of the variable gain units. The portable mobile terminal and the transmission unit can control the transmission power in multistage throughout a wide range, and can minimize the phase variation of the transmission signal at that time.

Abstract: Methods, systems, and arrangements enable balanced base station transmitter output power levels with respect to a receiving mobile station in a macro-diversity communication by adjusting a base station transmitter output power level responsive to power control command(s) sent by the mobile station and the (current) transmitter output power level of the base station. In a fixed adjustment step embodiment, power level convergence is enabled by adjusting the transmitter output power level of a given base station by a greater amount (e.g., than the nominal amount) when a power control command orders a power adjustment of the transmitter output power level towards a reference level and by adjusting the transmitter output power level by a lesser amount when a power control command orders a power adjustment of the is transmitter output power level away from the reference level. A continuous adjustment step embodiment is also disclosed.

Abstract: Techniques to linearly (in dB) adjust the gains of variable gain elements (i.e., variable gain amplifiers or VGAs) in a receiver or transmitter. An input control signal is provided to a conditioning circuit that conditions the control signal to achieve various signal characteristics. The input control signal is limited to within a particular range of values, temperature compensated, scaled (or normalized) to the supply voltages, shifted with an offset, or manipulated in other fashions. The conditioned signal is then provided to an input stage of a linearizer that generates a set of exponentially related signals. This is achieved using, for example, a differential amplifier in which the conditioned control signal is applied to the inputs of the differential amplifier and the collector currents from the differential amplifier comprises the exponentially related signals. An output stage within the linearizer receives the exponentially related signals and, in response, generates a gain control signal.

Abstract: The present invention provides power amplification circuitry having multiple amplifier stages in series and adapted to facilitate polar modulation. As such, the amplifier circuitry receives a frequency signal representing the frequency and phase components of the signal to be transmitted, as well as an amplitude signal presenting the amplitude component of the signal to be transmitted. The frequency component is amplified by the amplification circuitry. The amplitude component controls the supply voltage provided to the amplifier stages in the amplification circuitry. To increase the dynamic range of the amplification circuitry, the final stage or stages of the amplification circuitry are selectively disabled when lower output powers are necessary, and enabled when higher output powers are required.

Abstract: A radio apparatus (1), in particular for mobile radio, of a first predetermined power stage is proposed, whose broadcasting power can be increased by connecting a HF amplifier circuit. The radio apparatus (1) has an antenna output (5), to which an input (10) of a HF amplifier circuit (15) can be connected, for operating the radio apparatus (1) at a higher, second power stage. As a function of the HF amplifier circuit (15) connected to the radio apparatus (1), a transmitter unit (20) of the radio apparatus (1) outputs signals for transmission to a radio network, which signals contain the information about operation at the applicable power stage.

Abstract: A system and method for dynamically adjusting the operating bias of an RF transmitter amplifier in response to a power control signal. The invention provides high-efficiency RF power amplification for applications where the available power source is limited. The invention uses a power control signal resident in wireless communication system architectures with a detector and voltage to current converter to arrive at a dynamic amplifier operating bias.

Abstract: A highly efficient radio frequency (RF) transmitter provides both wide bandwidth and an extended power control range. The RF transmitter includes stage switching, bias adjustment, and drain supply modulation. These components are used to provide fine and coarse power control and EER envelope fluctuations. The RF transmitter is useful in wireless communications to increase both handset talk time and battery life.

Abstract: A radio communication apparatus is provided with a first variable power amplifier 13 and a second variable power amplifier 14 in a radio transmission unit 22, and also a variable amplifier 16 is provided at a prestage of a modulation unit 15. A transmission power control bit is extracted from a reception signal sent from a communication counter station by a variable power amplifying-controlling unit 18. The variable power amplifying-controlling unit 18 updates a value of transmission power stored in an own station based upon the value of this extracted transmission power control bit, and also compares the updated transmission value with a predetermined threshold value. Based upon this comparison result, the first and second variable power amplifier 13 and 14, and the variable amplifier 16 are controlled in either a serial control manner or a parallel control manner so as to perform a variable power amplification, so that the own transmission power is adjusted.

Abstract: A control device has an input section which inputs a predetermined signal, an amplification section of a variable gain type which amplifies the predetermined signal, and a feedback loop which inputs a signal output from the amplification section and adjusts a gain of the amplification section to keep the output signal constant.

Abstract: As the gain control amplifiers for amplifying the reception signal, the step amplifiers are used. Two sets of these step amplifiers are provided and are then controlled to be used alternately. When switching of the gain occurs, after the gain is switched with the step amplifier not operated and offset is cancelled, the amplifier to which the reception signal is inputted is switched. Accordingly, the step amplifier can be used as the gain control amplifier for amplifying the reception signal to provide almost constant power consumption even when the gain is changed depending on the intensity of reception signal in the semiconductor integrated circuit device for communication to form a wireless communication system of dual-mode or more modes including the W-CDMA system. As a result, the operation life of battery, namely, the reception waiting period and communication period by single charging process can be expanded.

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.