Techniques are described for using valley detection for supply voltage modulation in power amplifier circuits. Embodiments operate in context of a power amplifier circuit configured to be driven by a supply voltage generated by a supply modulator and to receive an amplitude-modulated (AM) signal at its input. The output of the power amplifier circuit can be fed to a valley detector that can detect a valley level corresponding to the bottom of the envelope of the AM signal. The detected valley level can be fed back to the supply modulator and compared to a constant reference. In response to the comparison, the supply modulator can vary the supply voltage to the power amplifier circuit in a manner that effectively tracking the envelope of the power amplifier circuit's output signal, thereby effectively seeking a flat valley for the output signal's envelope.

Devices, methods, and programs for billing for electric power. A billing method may include generating billing information for an amount related to electric power transmitted by a power supply device, performing a billing process based on the billing information, and selectively transmitting electric power based on the result of the billing process. A power supply device may include a billing information generating unit, a billing processing unit, and a power control unit. Another billing method may include determining whether billing information has been received, performing a billing process after it is determined that the billing information has been received, transmitting a response signal to a power supply device, and providing notice regarding information related to the billing process. A power receiving device may include a billing processing unit, a power control unit, and a notice control unit.

Devices, methods, and programs for billing for electric power. A billing method may include generating billing information for an amount related to electric power transmitted by a power supply device, performing a billing process based on the billing information, and selectively transmitting electric power based on the result of the billing process. A power supply device may include a billing information generating unit, a billing processing unit, and a power control unit. Another billing method may include determining whether billing information has been received, performing a billing process after it is determined that the billing information has been received, transmitting a response signal to a power supply device, and providing notice regarding information related to the billing process. A power receiving device may include a billing processing unit, a power control unit, and a notice control unit.

There are included a carrier wave generating unit (4) that generates a carrier wave signal; a modulating unit (6) that generates a modulated wave signal obtained by amplitude-modulating the carrier wave signal generated by the carrier wave generating unit (4) using an audio signal; an absolute value converting unit (7) that converts the audio signal into an absolute value; an exponentially weighted moving average unit (8) that performs an exponentially weighted moving average process on the audio signal converted by the absolute value converting unit (7), using an audio signal obtained one sampling period ago, to estimate a sound pressure level of the audio signal; and a multiplying unit (10) that multiplies the carrier wave signal generated by the carrier wave generating unit (4) by the sound pressure level estimated by the exponentially weighted moving average unit (8).

Techniques are described for using valley detection for supply voltage modulation in power amplifier circuits. Embodiments operate in context of a power amplifier circuit configured to be driven by a supply voltage generated by a supply modulator and to receive an amplitude-modulated (AM) signal at its input. The output of the power amplifier circuit can be fed to a valley detector that can detect a valley level corresponding to the bottom of the envelope of the AM signal. The detected valley level can be fed back to the supply modulator and compared to a constant reference. In response to the comparison, the supply modulator can vary the supply voltage to the power amplifier circuit in a manner that effectively tracking the envelope of the power amplifier circuit's output signal, thereby effectively seeking a flat valley for the output signal's envelope.

An RF generator includes: a modulation circuit outputting a pulsed RF signal; a variable attenuation circuit adjusting the level of the pulsed RF signal; an output power detecting unit detecting an output power value of the power output from the device; a first comparative arithmetic circuit outputting a first level control signal for controlling the level of the adjusted pulsed RF signal on the basis of a first detected voltage value and a set voltage value set in advance; a second comparative arithmetic circuit outputting a second level control signal for controlling the level of the adjusted pulsed RF signal on the basis of a second detected voltage value and the set voltage value; and a switching circuit switching between the value of the first level control signal and the value of the second level control signal depending on a switching timing setting value.

A SWIPT (simultaneous wireless information and power transfer) device based on the modulation of power supply ripple of magnetron includes a magnetron power supply, a magnetron, an IF (intermediate frequency) signal generator and a first capacitor. The first and second cathode power lines are provided between two ends of the magnetron power supply and two ends of the cathode of the magnetron respectively. One end of the first capacitor is connected with the IF signal generator, and another end of the first capacitor is connected with the first cathode power line. A SWIPT method includes applying an IF signal which is equivalent to the ripple of anode voltage of the magnetron to the anode voltage of the magnetron; taking a resonance signal excited by the magnetron as a local oscillation signal; generating a new signal at an output end of the magnetron, and radiating the new signal through an antenna.

A waveform synthesis technique for radio frequency identification (RFID) transmitters and an RFID system making us of the technique are disclosed. The RFID transmitter in example embodiments synthesizes a continuous transmitter waveform from a symbol alphabet without Nyquist or interpolation filters. High spectral occupancy waveforms are achieved which include the ability to do both linear and nonlinear predistortion with no increase in computational load once the signal set has been adapted to compensate for linear and nonlinear distortion in the transmitter analog circuitry. A polarity generator can be used to impart the required polarity to each waveform. The RFID transmitter can be employed in RFID readers to reduce the computational requirements of the digital signal processor (DSP).

A waveform synthesis technique for radio frequency identification (RFID) transmitters and an RFID system making us of the technique are disclosed. The RFID transmitter in example embodiments synthesizes a continuous transmitter waveform from a symbol alphabet without Nyquist or interpolation filters. High spectral occupancy waveforms are achieved which include the ability to do both linear and nonlinear predistortion with no increase in computational load once the signal set has been adapted to compensate for linear and nonlinear distortion in the transmitter analog circuitry. A polarity generator can be used to impart the required polarity to each waveform. The RFID transmitter can be employed in RFID readers to reduce the computational requirements of the digital signal processor (DSP).

Methods and devices are disclosed driving one or more P-Intrinsic-N (PIN) diodes by receiving an input and generating a plurality of pulses based on the input, a first pulse of the plurality of pulses controls a rise time of an RF envelope generated by an RF interface and a second pulse of the plurality of pulses controls a fall time of the RF envelope generated by the RF interface. The methods and devices may further be disclosed combining the plurality of pulses to generate a drive signal, delivering the drive signal to the RF interface including one or more PIN diodes, and generating the RF envelope by driving the one or more PIN diodes with the drive signal, and the amplitude or a pulse width of the first pulse is independently adjustable from the amplitude or the pulse width of the second pulse.