Digital broadcasting receiving unit and digital broadcasting system

摘要

This invention provides a digital broadcasting receiving unit capable of achieving synchronization of time information between a base station and a receiving unit with reference clock without use of a crystal oscillator (VCXO) having a variable frequency. The crystal oscillator oscillates a clock of a predetermined fixed frequency. A variable digital dividing circuit divides a fixed frequency by a division ratio so as to change the division ratio. A system decoder detects reference time information from the base station. A reference counter generates time information of a receiving unit. A phase comparator detects a difference between reference time information and time information. A division ratio control circuit controls the change of the division ratio based on the difference. The reference counter generates time information based on a clock having a frequency obtained by dividing by the variable digital dividing circuit and feeds back time information to the phase comparator.