Broadcast signal detecting method and broadcast signal detecting device

A broadcast signal detecting method for detecting a broadcast signal of a radio broadcast of an all-digital system, including:

• a receiving step for receiving a broadcast signal of a first frequency;
• a first evaluating step for evaluating whether or not reception quality of the broadcast signal of the first frequency, received through the receiving step, satisfies setting conditions;
• a changing step for changing the frequency to be received by the receiving step to a second frequency that is within a predetermined range from the first frequency if it is evaluated in the first evaluating step that the reception quality of the broadcast signal of the first frequency satisfies the setting conditions;
• a converting step for converting the broadcast signal of the second frequency received in the receiving step to a signal of an intermediate frequency;
• a second evaluating step for evaluating whether or not a frequency offset is within a predetermined range, the frequency offset is the amount of offset between a reference frequency and the frequency of the converted signal of the intermediate frequency;
• an acquiring step for performing a demodulating process on the broadcast signal of the first frequency and acquiring data included in the broadcast signal of the first frequency, if it is evaluated in the second evaluating step that the frequency offset is within the predetermined range;
• and
• a third evaluating step for evaluating whether or not the broadcast signal of the first frequency is a broadcast signal of a broadcasting station by evaluating whether or not predetermined data is included in the acquired data.