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A method for wireless communication that dynamically adjusts RF amplifier operating bias for the subscriber unit's transmitter 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.
A transmitter comprises a power amplifier (PA) with a power supply input (PI) and an output (PAO) to supply a transmission signal (Vo) with an output power (Po). A power supply (PS) has power supply outputs (PSO1, PSO2) to supply a first power supply voltage (PV1) with a first level and a second power supply voltage (PV2) with a second level, higher than the first level. A switching circuit (SC) is arranged between the power supply outputs (PSOI, PSQ2) and the power supply input (PI) to supply a...
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 discre...
A memory effect distortion component compensating unit compensates for a distortion component caused by a memory effect of an amplifier by using a time difference of results from raising an input signal to even power. For example, the amplifier may include a memory effect distortion component compensating unit having an even power raising unit for raising an input signal to even power, an even power raising result delaying unit for delaying a signal of a result of even power raising, an even pow...
A multi-band radio frequency (RF) receiving method in a mobile communication system having a reduced size and cost includes receiving RF wave signals for four or more non-overlapping bands, primarily filtering a first wide band including adjacent first and second bands and a second wide band including adjacent third and fourth bands from the received RF wave signals, low-noise amplifying the RF wave signals of the first and second wide bands, respectively, secondarily filtering a third wide band...
An automatic power control (APC) circuit for use with a radio telecommunication apparatus. The apparatus transmits radio frequency signals at a power level prescribed by a level control signal. In the automatic power control circuit, transmission power level is detected from the output of a duplexer. Accordingly, even if signal loss in a filter of the duplexer varies on the frequency of signals passing therethrough, transmission power level is accurately detected and the detected level is feedba...
A radio frequency ("RF") power amplifier circuit as described herein is configured to detect and measure an output load mismatch and to adjust the operating characteristics of the RF power amplifier to reduce output signal distortion. The circuit includes a directional RF signal coupler that obtains a coupled reflected RF signal that is indicative of the output load mismatch. The coupled reflected RF signal is processed to generate one or more bias control signals for the RF power amplifier. In ...
A frequency synthesizer modulates a signal by directly modulating a signal input to a voltage controlled oscillator (VCO) associated with the frequency synthesizer. The modulation signal has a bandwidth greater than a closed-loop bandwidth of the frequency synthesizer. The frequency synthesizer suppresses the modulation signal from a feedback path of the synthesizer.
A method and arrangement for controlling the power of a transmission amplifier reliably within as wide a power band as possible, for a desired transmission power level which is less than a predetermined limit value. In the present invention, a portion of the power emitted from the transmission amplifier is output through a switching device in addition to the power which is output through a directional coupler, and is used to control the transmission amplifier.
A transmission power control in a wireless communication, in that based upon transmission power designation information "A" functioning as a power control target derived from a transmission power designating unit 16, a transmission power error "E" is detected from a difference between a detection value "D" of an outputted transmission signal and a power control target value "C". This transmission power error "E" is multiplied by a loop gain "G" of a feedback loop set by a loop gain setting unit ...
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