Power amplifying device
An outphasing power amplifying device includes a switching signal generating circuit configured to generate a switching pulse signal for switching a class-D power amplifier from two types of sinusoidal wave generated based on amplitude and phase of a modulated wave to be transmitted. The switching signal generating circuit includes: a sin calculation unit and a cos calculation unit for converting phase information of the two types of sinusoidal wave into a quadrature format; a DA converter for converting the quadrature-format phase information; a first filter for removing an aliasing component from the analogue signal; an analogue quadrature modulator for generating a sinusoidal wave from the analogue signals by using a local signal; a second filter for allowing a radio frequency and a component in the vicinity thereof to pass therethrough; and a comparator for converting the sinusoidal wave into a switching pulse signal by comparison with a reference voltage.
1. An outphasing power amplifying device including a full-bridge class-D power amplifier, comprising:
a switching signal generating circuit configured to generate a switching pulse signal for switching the class-D power amplifier from two types of sinusoidal wave generated based on an amplitude and a phase of a modulated wave to be transmitted,
wherein the switching signal generating circuit includes:
a sin calculation unit and a cos calculation unit which are configured to convert phase information of the two types of sinusoidal wave into a quadrature format;
a DA converter configured to convert the quadrature-format phase information from each of the sin calculation unit and the cos calculation unit into an analogue signal;
a first filter configured to remove an aliasing component from the analogue signal inputted from the DA converter;
an analogue quadrature modulator configured to generate a sinusoidal wave from the analogue signals inputted from the first filter by using a local signal;
a second filter configured to allow a predetermined radio frequency and a component in the vicinity thereof in the sinusoidal wave inputted from the analogue quadrature modulator to pass therethrough; and
a comparator configured to convert the sinusoidal wave inputted from the second filter into a switching pulse signal by comparison with a reference voltage.
2. The power amplifying device of claim 1 , wherein the quadrature-format phase information is updated at a predetermined interval based on the modulated wave to be transmitted.
3. An outphasing power amplifying device including a full-bridge class-D power amplifier, comprising:
a switching signal generating circuit configured to generate a switching pulse signal for switching the class-D power amplifier from two types of sinusoidal wave generated based on an amplitude and a phase of a modulated wave to be transmitted,
wherein the switching signal generating circuit includes:
a DDS (Direct Digital Synthesizer) configured to update a phase accumulator at a predetermined frequency based on phase information of the two types of sinusoidal wave and output an amplitude value of a sinusoidal wave corresponding to the phase of the phase accumulator;
a DA converter configured to convert the amplitude value of the sinusoidal wave inputted from the DDS into an analogue signal;
a second filter configured to remove a clock component from the analogue signal inputted from the DA converter; and
a comparator configured to convert the analogue signal inputted from the second filter into a switching pulse signal by comparison with a reference voltage.
4. The power amplifying device of claim 3 , wherein a phase shift value added to an output of the phase accumulator is updated at a predetermined interval based on the modulated wave to be transmitted.