| 摘要 |
PROBLEM TO BE SOLVED: To provide a television broadcast receiving apparatus for effectively reducing SN ratio deterioration due to interference outside of a reception band such as adjacent channel interference. SOLUTION: The television broadcast receiving apparatus includes: a PLL unit for controlling a frequency of a local oscillation signal in a reception channel; a frequency conversion unit for generating an intermediate frequency signal by using the local oscillation signal; a filter unit to be tuned to a frequency band of the intermediate frequency signal; a demodulation unit for demodulating the intermediate frequency signal which has passed through the filter unit; an SN ratio measurement unit for measuring an SN ratio of the demodulated signal by the demodulation unit; an operation unit for controlling the PLL unit; and a filter control unit for controlling the tuning frequency of the filter unit. The operation unit determines the tuning frequency of the filter unit that renders the SN ratio favorable in a range equivalent to an occupied frequency bandwidth of the reception channel, changes the tuning frequency control signal of the filter unit that is outputted from the filter control unit based on a result of the determination, and changes reception characteristic to be set to optimum reception characteristics. COPYRIGHT: (C)2011,JPO&INPIT |
