Digital broadcasting signal receiver

摘要

A receiver for a digital broadcasting service have a compatibility between tuning to a desired channel at a short period of time and an improve ment of a bit error rate (BER) characteristics. In a case where a target wave is fluctuated, to prevent the receiver from having a significant declination of BER characteristics and to ensure the reproduction of high quality images, the receiver includes an automatic gain controller including a loop filter in which the frequency range of the loop filter can be switched according to an output of a synchronous state discriminator. The frequency band of the loop filter is selectively adjusted to one setting designed for minimizing the duration for tuning a desired channel before a synchronous state is established. After the synchronous state established, the frequency band of the loop filter is switched to another setting designed for enhancing BER characteristics.