Abstract:
A signal amplification apparatus includes a first modulator configured to receive an envelope signal, use a predetermined reference level to separate the received envelope signal into a first period and a second period, digitally modulate a signal of the second period to output the digitally modulated signal to a first output terminal, and output a signal of the first period to a second output terminal. Further, the signal amplification apparatus includes a second modulator configured to mix the digital modulated signal input through the first output terminal with a phase modulated carrier signal; an envelope modulator configured to output the signal of the first period as a power supply signal; and a power amplifier configured to amplify the mixed signal output by the second modulator to output the amplified signal.
Abstract:
Provided is a method of correcting a time misalignment between envelope and phase components in a transmitting apparatus which separates envelope and phase components of a signal, processes them, and then recombines them to transmit the recombined signal. For this, in a method of correcting a time misalignment between envelope and phase components according to an embodiment of the present invention, a time misalignment is corrected by applying a time delay to at least one of envelope and phase components in digital and analog signal processing operations, or applying a time delay to an envelope or phase component by a pre-processing operation.
Abstract:
Provided is a delta-sigma modulator including a summer summing an input signal and an analog signal, a first integrator integrating an output signal from the summer and outputting a first integration signal, a second integrator integrating the first integration signal and outputting a second integration signal, a comparator comparing the second integration signal and a reference signal and outputting a digital signal according to the comparison result, and a digital-to-analog converter converting the digital signal into an analog signal in response to a clock signal and outputting the converted analog signal, wherein the second integrator operates based on an Nth order (where N is natural number of 1 or greater) transfer function.