| 摘要 |
<p>A receiver (10), such as a television receiver, includes a tuner (20) and a receiver integrated circuit (100). The receiver integrated circuit (100) includes a high-image rejection mixer (110) and an analog-to-digital converter (ADC) (130) to provide a digital representation of signals received by the tuner (20), which may be in one of several formats, such as an NTSC format or a PAL format. Digital signals from the ADC (130) are digitally down converted (140, 150) and filtered (144, 154, 192) and may be formatted as an intermediate frequency (IF) signal or be decoded into digital video signals for a display device (60) and digital audio signals for an audio reproduction device (70). As a result of the digital frequency conversion, efficient digital filtering is employed in place of conventional bulky and costly SAW filters, and digital words having a greater number of bits than the digital data produced by the ADC (130) are available for digital signal processing.</p> |
