| 摘要 |
PURPOSE: A bandpass modulator is provided to increase stability, the size of an output signal, and coding efficiency by reducing the signal accumulation of a resonator. CONSTITUTION: A bandpass delta-sigma modulator(200) comprises first to fourth calculation units(202,204,206,208), first and second resonant units(212,214), first and second quantization units(222,224), a shifter(232), and a delay unit(242). The first and the second resonant units are parallely connected. The first calculation unit, the first resonant unit, and a first quantization unit are included in a first stage. The second calculation unit, the second resonant unit, and the second quantization unit are included in a second stage. The first calculation unit is connected to the input of the first resonant unit. The first resonant unit passes through a signal having a specific frequency band from an output signal of the first calculation unit.
|
