| 摘要 |
<p>A method of tuning channels for television and CATV devices includes the step of receiving a radio frequency input (101) signal having at least one carrier signal at frequency fs associated with a selected broadcast channel. The RFI signal is upconverted (110) by m (140) to a first intermediate frequency wherein the carrier signal is located at fs+m. The first intermediate frequency is filtered (120). The filtered first intermediate frequency is down-converted (130) by n (150) to a second intermediate frequency wherein the second intermediate frequency includes the carrier signal at fs+m-n. Additional methods for improving the reception of the selected channel include the step of varying m and n in order to avoid frequency-dependent anomalies within the pass band of the filter.</p> |
