摘要:
A system and method for modulating a phase component of an electromagnetic signal includes a phase/frequency detector having first and second inputs and an output. The first phase/frequency detector input may be configured to receive a reference signal. The system may include an oscillator having an input and an output. The oscillator may be configured to generate a desired oscillator output signal at its output. A divider may be configured to receive the oscillator output signal. The divider may have a divider count input and a divider carryout output that may be connected to the second phase/frequency detector input. A loop filter may be connected in series between the phase/frequency detector output and the oscillator input. The loop filter has a transfer function including at least two frequency response rate change points, where each of the frequency rate change points corresponds to a pole or a zero in the transfer function.
摘要:
Circuits, systems and methods that utilize two transducers, of which at least one is a piezoelectric transducer, adapted and coupled to receive and/or generate signals in the forms of sound waves, mechanical vibrations, and/or electromagnetic energy. In one version, two transducers each receive and/or generate separate vibrational energy signals that bear information. Two or more transducers coupled to a switching circuit may send or receive piezo-electrical circuit output signals that include a carrier wave having different frequencies that are within separate frequency ranges. Two or more transducers may generate output signals that are simultaneously processed by or multiplexed by a switching circuit.
摘要:
Circuits, systems and methods that utilize two transducers, of which at least one is a piezoelectric transducer, adapted and coupled to receive and/or generate signals in the forms of sound waves, mechanical vibrations, and/or electromagnetic energy. In one version, two transducers each receive and/or generate separate vibrational energy signals that bear information. Two or more transducers coupled to a switching circuit may send or receive piezo-electrical circuit output signals that include a carrier wave having different frequencies that are within separate frequency ranges. Two or more transducers may generate output signals that are simultaneously processed by or multiplexed by a switching circuit.
摘要:
A multi-carrier transmitter and methods thereof are provided. For example, a multi-carrier transmitter comprises a processor operable to receive a plurality of baseband signals. Each of the plurality of baseband signals correspond to a separate data communication. A modulator is in communication with the processor. A non-linear device is in communication with the modulator. The processor is further operable to combine the plurality of baseband signals to generate a composite baseband signal. The modulator is operable to modulate a carrier signal with the composite baseband signal to generate a multi-carrier signal. The multi-carrier signal is provided to an input of the non-linear device.
摘要:
A method and apparatus for a multi-mode and multi-rate telemetry transmitter includes a digital baseband lineup, a digital-to-analog converter (“DAC”), and an analog reconstruction filter. The digital baseband lineup may be programmed to any desired bit rate, enabling the transmitter to support multi-rate capabilities. Different coefficients and numerical values may be programmed in the digital baseband lineup to support any desired modulation scheme, enabling the transmitter to support multi-mode capabilities. The digital baseband lineup may be designed by implementing up-sampling stages, down-sampling stages, and digital filters in a variety of arrangements.
摘要:
A modulation path synchronization apparatus in a polar transmitter includes a modulation path to receive a training waveform, a detector coupled to the modulation path, and a processor coupled to the detector. The detector is to detect a modulated training waveform. The processor is to determine a delay between the training waveform and the modulated training waveform.
摘要:
A digital polar transmitter includes a baseband processor configured to receive an input signal and to convert the input signal into a baseband amplitude component and a baseband phase component. The transmitter also includes a phase modulator in communication with the baseband processor. The phase modulator is configured to modulate an RF carrier signal based on the phase component and to generate a phase-modulated RF carrier signal. A power amplifier is provided in communication with the baseband processor and the phase modulator. The power amplifier is configured to amplify the phase-modulated RF carrier signal based on the baseband amplitude component and to generate an amplified RF signal. The transmitter also includes a digital feedback loop in communication with the power amplifier and the baseband processor. The digital feedback loop is configured to detect the amplified RF signal and to provide a digital amplitude feedback signal and a detected phase feedback signal to the baseband processor.
摘要:
A system is provided for processing a communication signal including a baseband amplitude component and a baseband phase component. The system includes an amplitude predictor configured for closed-loop pre-distortion of a baseband amplitude component, an amplitude lookup table configured for open-loop pre-distortion of the baseband amplitude component, and an amplitude interpolator configured to build up the amplitude lookup table during a closed-loop calibration period. The system also includes a phase predictor configured for closed-loop pre-distortion of a baseband phase component, a phase lookup table configured for open-loop pre-distortion of the baseband phase component, and a phase interpolator configured to build up the phase lookup table during a closed-loop calibration period.
摘要:
Circuits, systems and methods that utilize two transducers, of which at least one is a piezoelectric transducer, adapted and coupled to receive and/or generate signals that include a power transmission component and an informational content in the forms of sound waves, mechanical vibrations, and/or electromagnetic energy. In one version, two transducers each receive and/or generate separate vibrational energy signals that bear information and transmit electrical power. Two or more transducers coupled to a switching circuit may send or receive piezo-electrical circuit output signals that include a carrier wave having different frequencies that are within separate frequency ranges. Two or more transducers may generate output signals that are simultaneously processed by or multiplexed by a switching circuit.
摘要:
Circuits, systems and methods that utilize two transducers, of which at least one is a piezoelectric transducer, adapted and coupled to receive and/or generate signals in the forms of sound waves, mechanical vibrations, and/or electromagnetic energy. In one version, two transducers each receive and/or generate separate vibrational energy signals that bear information. Two or more transducers coupled to a switching circuit may send or receive piezo-electrical circuit output signals that include a carrier wave having different frequencies that are within separate frequency ranges. Two or more transducers may generate output signals that are simultaneously processed by or multiplexed by a switching circuit.