摘要:
A system for controlling amplifier power is provided. The system includes a voltage envelope detector receiving a voltage signal and generating an attenuated voltage envelope signal. A current envelope detector receives a current signal and generates an attenuated current envelope signal. A controller receives power level data and generates attenuation control data for the voltage envelope signal and the current envelope signal. A detector receives the voltage envelope signal and the current envelope signal and generates a control signal based on the greater of the voltage envelope signal and the current envelope signal. A power amplifier level controller receives the control signal and generates a power amplifier level control signal.
摘要:
A system for controlling the power output of a power amplifier includes a power amplifier through which a transmit signal having an amplitude-modulated (AM) component and a phase-modulated (PM) component is passed and amplified, the power amplifier comprising a forward path, a feedback signal comprising a portion of the output of the power amplifier, a first control loop configured to receive the feedback signal and configured to apply an amplitude modulated (AM) signal to the power amplifier and configured to control the gain of the power amplifier, a second control loop configured to receive the feedback signal and configured to correct for offsets in the forward path and to linearize the first control loop; and a third control loop configured to receive the feedback signal and configured to control the phase of the PM component of the transmit signal.
摘要:
A system for controlling amplifier power is provided. The system includes a voltage envelope detector receiving a voltage signal and generating an attenuated voltage envelope signal. A current envelope detector receives a current signal and generates an attenuated current envelope signal. A controller receives power level data and generates attenuation control data for the voltage envelope signal and the current envelope signal. A detector receives the voltage envelope signal and the current envelope signal and generates a control signal based on the greater of the voltage envelope signal and the current envelope signal. A power amplifier level controller receives the control signal and generates a power amplifier level control signal.
摘要:
A system for controlling the power output of a power amplifier includes a power amplifier through which a transmit signal having an amplitude-modulated (AM) component and a phase-modulated (PM) component is passed and amplified, the power amplifier comprising a forward path, a feedback signal comprising a portion of the output of the power amplifier, a first control loop configured to receive the feedback signal and configured to apply an amplitude modulated (AM) signal to the power amplifier and configured to control the gain of the power amplifier, a second control loop configured to receive the feedback signal and configured to correct for offsets in the forward path and to linearize the first control loop; and a third control loop configured to receive the feedback signal and configured to control the phase of the PM component of the transmit signal.
摘要:
A system for controlling amplifier power is provided. The system includes a voltage envelope detector receiving a voltage signal and generating an attenuated voltage envelope signal. A current envelope detector receives a current signal and generates an attenuated current envelope signal. A controller receives power level data and generates attenuation control data for the voltage envelope signal and the current envelope signal. A detector receives the voltage envelope signal and the current envelope signal and generates a control signal based on the greater of the voltage envelope signal and the current envelope signal. A power amplifier level controller receives the control signal and generates a power amplifier level control signal.
摘要:
A system for controlling amplifier power is provided. The system includes a voltage envelope detector receiving a voltage signal and generating an attenuated voltage envelope signal. A current envelope detector receives a current signal and generates an attenuated current envelope signal. A controller receives power level data and generates attenuation control data for the voltage envelope signal and the current envelope signal. A detector receives the voltage envelope signal and the current envelope signal and generates a control signal based on the greater of the voltage envelope signal and the current envelope signal. A power amplifier level controller receives the control signal and generates a power amplifier level control signal.
摘要:
A transmitter for a wireless handset having a modified translation loop architecture. The transmitter includes a VCO that generates a modulated transmit signal having a frequency fTx, and a modulated signal source that generates a modulated LO signal with a frequency fLO. A mixer mixes the transmit signal with the LO signal to produce an IF signal having a frequency fIF. A first divider divides the LO signal frequency fLO by an integer M to generate a first comparison signal having a frequency fCF. A second divider divides the IF signal frequency fIF, after it is multiplied by an integer K, by an integer N to generate a second comparison signal having a frequency fCF. The transmit and LO signal frequencies have the relationship f Tx = f LO KM ± N M . A phase detector coupled to the first and second comparison signals compares the phases of the signals and outputs a control voltage to the VCO proportional to any phase differences between the signals.
摘要翻译:一种用于具有修改的平移环结构的无线手机的发射机。 发射机包括产生具有频率f Tx的调制的发射信号的VCO和产生具有频率为LO LO的调制LO信号的调制信号源。 混合器将发送信号与LO信号混合以产生具有频率f IF IF的IF信号。 第一分频器将LO信号频率f LO LO分频整数M以产生具有频率f CF1的第一比较信号。 第二分频器将IF信号频率f IF IF在乘以整数K之后除以整数N,以产生具有频率f CF1的第二比较信号。 发送和LO信号频率具有关系
摘要:
A system is disclosed for transmitting and receiving signals. The system includes the use of a frequency plan table a system for creating the frequency plan table. The frequency plan table relates carrier frequency channels to the operation of a synthesizer and a plurality of programmable frequency dividers in a locked loop. In a transmitter, a first programmable frequency divider accepts a reference signal and produces a comparison signal. A mixer accepts the reference signal and a transmission signal and produces a loop signal. A second programmable frequency divider accepts the loop signal and produces a loop signal having a divided intermediate frequency signal. A phase detector compares the comparison signal and the loop signal having a divided intermediate frequency and produces an output that controls a variable controlled oscillator. The variable controlled oscillator produces a modulated transmission signal.
摘要:
A software defined transmit architecture includes a plurality of individually selectable components that can be selectively enabled to transmit a data signal that complies with any of a plurality of transmission standards. The software defined transmit architecture comprises components that can be enabled by associated logic to transmit, for example, communications signals that comply with the global system for mobile communications (GSM), enhanced data rates for GSM evolution (EDGE), which employs TDMA, and wide band code division multiple access (WCDMA) transmission standards. A single transmit architecture supports multiple transmission standards, thus minimizing the number of components in a multi-band, multi-mode portable transceiver, while reducing the number of active components.
摘要:
Systems for controlling the frequency of the output signal of a controllable oscillator in a frequency synthesizer are provided. One such system comprises a controllable oscillator and a frequency control circuit. The controllable oscillator is configured to generate an output signal that has a predefined frequency. The controllable oscillator is also configured with a plurality of operational states that are controlled by the frequency control circuit. Each operational state of the controllable oscillator defines a distinct frequency for the output signal of the controllable oscillator. The frequency control circuit receives the output signal of the controllable oscillator and determines the distinct frequency for the output signal that best approximates the predefined frequency. The frequency control circuit may also provide a control signal to the controllable oscillator that is configured to change the controllable oscillator to the operational state corresponding to the distinct frequency that best approximates the predefined frequency.