| 摘要 |
PURPOSE: An adaptive LO(Local Oscillator) supplying part for increasing the linear dynamic area of a switching power amplifier is provided to form a modulated transmission system with high accuracy by increasing the linear dynamic area of a switching power amplifier. CONSTITUTION: A CORDIC(Coordinate Rotation Digital Computer) processor(100) receives a baseband signal. The baseband signal is converted to size information and phase information through the CORDIC processor. The phase information with a fixed size is inputted to a power amplifier(120). An LDO(Low-Drop Out)(110) controls the power voltage of the power amplifier according to the size information of a low frequency. The LDO serves as the power source and voltage regulator of the power amplifier. The modulation of the output signal, in which a size is modulated through the power amplifier, is formed to be identical to the modulation of a baseband signal. The accuracy of a final outputted signal is determined according to the linear dynamic area of the switching power amplifier. |
