Abstract: A transmitter includes an analog transmission circuit, a power amplifier, a voltage detector, a comparator, and a control circuit. The analog transmission circuit is configured to provide a first gain to a first analog signal, so as to generate a second analog signal. The power amplifier is configured to provide a second gain to the second analog signal, so as to generate an output signal to an antenna. The voltage detector is configured to detect a voltage level of the second analog signal. The comparator is configured to generate an indication signal according to the voltage level and a reference level. The control circuit is configured to adjust the first gain of the analog transmission circuit according to the indication signal.

Abstract: A transmitting circuit, which includes a power amplifier, a processing circuit, and a signal strength indicator circuit. The power amplifier is configured to amplify an input signal according to a power gain of the power amplifier to generate an output signal. The processing circuit is configured to adjust the power gain according to an indicating signal. The signal strength indicator circuit has a plurality of power detection ranges. The signal strength indicator circuit is configured to uses one of the plurality of power detection ranges to detect a power of the output signal to generate the indicating signal.

Abstract: The present invention discloses a power amplification apparatus having a digital pre-distortion mechanism that includes a digital pre-distortion circuit and a power amplifier. The digital pre-distortion circuit receives an original digital signal having an original real part and an original imaginary part. When a first one and a second one of the original real part and the original imaginary part are a low state voltage level and a high state voltage level, the digital pre-distortion circuit outputs a first and a second voltage levels equivalent to the low state voltage level as a first pre-distortion part and directly outputs the second one of the original real part and the original imaginary part as a second pre-distortion part to generate an input signal having an input real part and an input imaginary part each corresponding to one of the first pre-distortion part and the second pre-distortion part. The power amplifier receives the input signal to perform power amplification to generate an output signal.

Abstract: A signal strength indicator circuit, configured to detect a power of an output signal outputted by a power amplifier, includes a voltage gain circuit, a current gain circuit, a multiplier, and a buffer stage. The voltage gain circuit provides a first gain to the output signal to generate a first value of an indicating voltage when a voltage of the output signal is not greater than a threshold, and provides a second gain to generate a second value of the indicating voltage when the voltage of the output signal is greater than the threshold. The first gain is greater than the second gain. The current gain circuit generates an indicating current according to an input signal corresponding to the output signal. The multiplier multiplies the indicating voltage and the indicating current to generate an indicating power. The buffer stage converts the indicating power to the indicating signal.

Abstract: A power detector device includes a power detector circuit, a filter circuit, and a calibration circuitry. The power detector circuit is configured to detect a first signal to generate a second signal. The filter circuit is configured to filter the second signal to generate a third signal. The calibration circuitry is configured to determine first signal strength information in response to the third signal, adjust a gain of the power detector circuit to obtain second signal strength information, and combine the first signal strength information and the second signal strength information, in order to calibrate a detection power range of the power detector circuit to be linear.

Abstract: A signal strength indicator circuit, configured to detect a power of an output signal outputted by a power amplifier, includes a voltage gain circuit, a current gain circuit, a multiplier, and a buffer stage. The voltage gain circuit provides a first gain to the output signal to generate a first value of an indicating voltage when a voltage of the output signal is not greater than a threshold, and provides a second gain to generate a second value of the indicating voltage when the voltage of the output signal is greater than the threshold. The first gain is greater than the second gain. The current gain circuit generates an indicating current according to an input signal corresponding to the output signal. The multiplier multiplies the indicating voltage and the indicating current to generate an indicating power. The buffer stage converts the indicating power to the indicating signal.

Abstract: The present invention discloses a power amplification apparatus having a digital pre-distortion mechanism that includes a digital pre-distortion circuit and a power amplifier. The digital pre-distortion circuit receives an original digital signal having an original real part and an original imaginary part. When a first one and a second one of the original real part and the original imaginary part are a low state voltage level and a high state voltage level, the digital pre-distortion circuit outputs a first and a second voltage levels equivalent to the low state voltage level as a first pre-distortion part and directly outputs the second one of the original real part and the original imaginary part as a second pre-distortion part to generate an input signal having an input real part and an input imaginary part each corresponding to one of the first pre-distortion part and the second pre-distortion part. The power amplifier receives the input signal to perform power amplification to generate an output signal.

Abstract: The present invention discloses a power amplifier capable of adaptively operating in one of an energy efficient mode and a high output power mode. An embodiment of the power amplifier includes a first transistor, a second transistor, a first bias element, a second bias element, a third bias element and a plurality of switches. In the energy efficient mode, by the control over the on/off states of the switches, an inverter type power amplifier is realized with the first transistor, the second transistor, the second bias element and the third bias element. In the high output power mode, by the control over the on/off states of the switches, a common source amplifier or a common emitter amplifier is realized with the second transistor and the first bias element.

Abstract: The present invention discloses a power amplifier capable of adaptively operating in one of an energy efficient mode and a high output power mode. An embodiment of the power amplifier includes a first transistor, a second transistor, a first bias element, a second bias element, a third bias element and a plurality of switches. In the energy efficient mode, by the control over the on/off states of the switches, an inverter type power amplifier is realized with the first transistor, the second transistor, the second bias element and the third bias element. In the high output power mode, by the control over the on/off states of the switches, a common source amplifier or a common emitter amplifier is realized with the second transistor and the first bias element.