| 摘要 |
PURPOSE:To dispense with adjustment in a phase shifter in which a high frequency is handled by correcting a baseband input signal used as input to a quadrature amplitude modulator at a linearly coupled circuit to correct the phase error of the phase shifter in the quadrature amplitude modulator. CONSTITUTION:Two baseband signals are linearly coupled appropriately at the linearly coupled circuit 101, and are inputted to the quadrature amplitude modulator 106, and are inputted to multipliers 102, 103 in the modulator. A carrier is changed to apair of orthogonal carriers with phase difference of almost 90 deg. by the phase shifter 104, and they are multiplied by the baseband signals at the multipliers 102, 103, and are synthesized at an adder 105, then, modulation output is issued. |
