| 摘要 |
PROBLEM TO BE SOLVED: To provide a base band modulator, which can be easily adapted to various digital modulation systems, by providing first and second digital/analog converters(DAC) or the like for generating an in-phase (I) base band signal and a quadrature phase (Q) base band signal an output sample rate. SOLUTION: I state and Q state indexes are supplied to digital filters 104 and 106. Filtered I and Q symbol values, provided by the digital filters 104 and 106 are supplied to a resampler 108. The resampled symbol values, provided by the resampler 108 are supplied to digital analog converters(DACs) 110 and 112 and converted to an analog voltage at the output sample rate. Since the digital filters 104 and 106 can be easily constituted, the versatility of a digital base band modulator 100 is maximized. |
