Digital broadcast receiver
First Claim
1. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol and a second broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
- a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave;
a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal conforming to the first broadcast protocol;
a first demultiplexer for separating first data including tuning information from the first digital signal;
a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing a channel scan in the first broadcast protocol;
a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave;
a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal conforming to the second broadcast protocol;
a second demultiplexer for separating second data including tuning information from the second digital signal; and
a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing a channel scan in the second broadcast protocol;
whereinthe first controller and the second controller divide between them a plurality of channels included in the overlapping frequency band of the first broadcast protocol and the second broadcast protocol and execute channel scans in parallel as a first phase channel scan;
in the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present;
in the first phase channel scan, the second controller executes a channel scan in the second broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; and
after the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol on the channels indicated in the second scan use channel list, and the second controller executes a channel scan in the second broadcast protocol on the channels indicated in the first scan use channel list.
1 Assignment
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Accused Products
Abstract
The present invention provides a digital broadcast receiver which reduces the time needed for channel scans by performing efficient channel scanning when broadcasts in a plurality of broadcast protocols are received. As a first phase channel scan, a first controller and a second controller divide a plurality of channels included in an overlapping frequency band of a first broadcast protocol and a second broadcast protocol, and execute parallel channel scans. After the first phase channel scan, the first controller scans channels in which electrical signals generated from electromagnetic waves received by a second tuner in the first phase channel scan could not be demodulated by a second demodulator, and the second controller scans channels in which electrical signals generated from electromagnetic waves received by a first tuner could not be demodulated by a first demodulator.
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Citations
14 Claims
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1. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol and a second broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal conforming to the first broadcast protocol; a first demultiplexer for separating first data including tuning information from the first digital signal; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing a channel scan in the first broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal conforming to the second broadcast protocol; a second demultiplexer for separating second data including tuning information from the second digital signal; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing a channel scan in the second broadcast protocol;
whereinthe first controller and the second controller divide between them a plurality of channels included in the overlapping frequency band of the first broadcast protocol and the second broadcast protocol and execute channel scans in parallel as a first phase channel scan; in the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present; in the first phase channel scan, the second controller executes a channel scan in the second broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; and after the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol on the channels indicated in the second scan use channel list, and the second controller executes a channel scan in the second broadcast protocol on the channels indicated in the first scan use channel list. - View Dependent Claims (2, 3, 4)
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5. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol and a second broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal conforming to the first broadcast protocol; a first demultiplexer for separating first data including tuning information from the first digital signal generated by the first demodulator; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing a channel scan in the first broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal conforming to the second broadcast protocol; a second demultiplexer for separating second data including tuning information from the second digital signal generated by the second demodulator; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing a channel scan in the second broadcast protocol; a third tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a third demodulator for demodulating the electrical signal obtained from the third tuner and generating a first digital signal conforming to the first broadcast protocol; a third demultiplexer for separating first data including tuning information from the first digital signal generated by the third demodulator; and a third controller for controlling the third tuner, the third demodulator, and the third demultiplexer and executing a channel scan in the first broadcast protocol; a fourth tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a fourth demodulator for demodulating the electrical signal obtained from the fourth tuner and generating a second digital signal conforming to the second broadcast protocol; a fourth demultiplexer for separating second data including tuning information from the second digital signal generated by the fourth demodulator; and a fourth controller for controlling the fourth tuner, the fourth demodulator, and the fourth demultiplexer and executing a channel scan in the second broadcast protocol;
whereinthe first controller, the second controller, the third controller, and the fourth controller divide among them a plurality of channels included in the overlapping frequency band of the first broadcast protocol and the second broadcast protocol and execute channel scans in parallel as a first phase channel scan; in the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present; in the first phase channel scan, the second controller executes a channel scan in the second broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; in the first phase channel scan, the third controller executes a channel scan in the first broadcast protocol and generates a third scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, from information indicating reception status from the third tuner and the third demodulator; in the first phase channel scan, the fourth controller executes a channel scan in the second broadcast protocol and generates a fourth scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present, from information indicating reception status from the fourth tuner and the fourth demodulator; and after the first phase channel scan, the first controller and the third controller divide between them the channels indicated in the second scan use channel list and the fourth scan use channel list and execute a channel scan in the first broadcast protocol, and the second controller and the fourth controller divide between them the channels indicated in the first scan use channel list and the third scan use channel list and execute a channel scan in the second broadcast protocol.
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6. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol and a second broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal conforming to the first broadcast protocol; a first demultiplexer for separating first data including tuning information from the first digital signal generated by the first demodulator; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing a channel scan in the first broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal conforming to the second broadcast protocol; a second demultiplexer for separating second data including tuning information from the second digital signal generated by the second demodulator; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing a channel scan in the second broadcast protocol; a third tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a third demodulator for demodulating the electrical signal obtained from the third tuner and generating a first digital signal conforming to the first broadcast protocol; a third demultiplexer for separating first data including tuning information from the first digital signal generated by the third demodulator; and a third controller for controlling the third tuner, the third demodulator, and the third demultiplexer and executing a channel scan in the first broadcast protocol; a fourth tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a fourth demodulator for demodulating the electrical signal obtained from the fourth tuner and generating a second digital signal conforming to the second broadcast protocol; a fourth demultiplexer for separating second data including tuning information from the second digital signal generated by the fourth demodulator; and a fourth controller for controlling the fourth tuner, the fourth demodulator, and the fourth demultiplexer and executing a channel scan in the second broadcast protocol;
whereinwhen the second tuner, the second demodulator, and the second demultiplexer are being used to receive a service broadcast in the second broadcast protocol, the first controller, the third controller, and the fourth controller divide among them a plurality of channels included in the overlapping frequency band of the first broadcast protocol and the second broadcast protocol and execute parallel channel scans as a first phase channel scan, in the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, in the first phase channel scan, the third controller executes a channel scan in the first broadcast protocol and generates a third scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, from information indicating reception status from the third tuner and the third demodulator, in the first phase channel scan, the fourth controller executes a channel scan in the second broadcast protocol and generates a fourth scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present, from information indicating reception status from the fourth tuner and the fourth demodulator, and after the first phase channel scan, the first controller and the third controller divide between them the channels indicated in the fourth scan use channel list and execute a channel scan in the first broadcast protocol, and the fourth controller executes a channel scan in the second broadcast protocol the channels indicated in the first scan use channel list and the third scan use channel list; and when the first tuner, the first demodulator, and the first demultiplexer are being used to receive a service broadcast in the first broadcast protocol, the second controller, the third controller, and the fourth controller divide among them a plurality of channels included in the overlapping frequency band of the first broadcast protocol and the second broadcast protocol and execute parallel channel scans as a fourth phase channel scan, in the fourth phase channel scan, the second controller executes a channel scan in the second broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; in the fourth phase channel scan, the third controller executes a channel scan in the first broadcast protocol and generates a third scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, from information indicating reception status from the third tuner and the third demodulator, in the fourth phase channel scan, the fourth controller executes a channel scan in the second broadcast protocol and generates a fourth scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present, from information indicating reception status from the fourth tuner and the fourth demodulator, and after the fourth phase channel scan, the third controller executes a channel scan in the first broadcast protocol on the channels indicated in the second scan use channel list and the fourth scan use channel list, and the second controller and the fourth controller divide between them the channels indicated in the third scan use channel list and execute a channel scan in the second broadcast protocol.
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7. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol and a second broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal conforming to the first broadcast protocol; a first demultiplexer for separating first data including tuning information from the first digital signal; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing a channel scan in the first broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal conforming to the second broadcast protocol; a second demultiplexer for separating second data including tuning information from the second digital signal; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing a channel scan in the second broadcast protocol;
whereinthe first controller and the second controller divide between them a plurality of channels included in the overlapping frequency band of the first broadcast protocol and the second broadcast protocol and execute channel scans in parallel as a first phase channel scan; in the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present; in the first phase channel scan, the second controller executes a channel scan in the second broadcast protocol and generates a second scan use channel list indicating channels in which the electrical signal generated from the electromagnetic wave received by the second tuner could be demodulated and, from information indicating reception status from the second tuner and the second demodulator, channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; and after the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol on the channels indicated in the second scan use channel list, and the second controller executes a channel scan in the second broadcast protocol on the channels indicated in the first scan use channel list. - View Dependent Claims (8)
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9. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol, a second broadcast protocol, and a third broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal; a first demultiplexer for separating first data including tuning information from the first digital signal; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing channel scans in the first broadcast protocol and the third broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal; a second demultiplexer for separating second data including tuning information from the second digital signal; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing channel scans in the second broadcast protocol and the third broadcast protocol;
whereinthe first controller and the second controller divide between them a plurality of channels included in the overlapping frequency band of the first broadcast protocol and the second broadcast protocol and execute the channel scan in the first broadcast protocol and the channel scan in the second broadcast protocol in parallel as a first phase channel scan; in the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present; in the first phase channel scan, the second controller executes a channel scan in the second broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator a second scan use channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; and as channel scans after the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol on the channels indicated in the second scan use channel list, and generates, from information indicating reception status from the first tuner and the first demodulator, a third scan use first channel list indicating channels identified as channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, the second controller executes a channel scan in the second broadcast protocol on the channels indicated in the first scan use channel list, and generates, from information indicating reception status from the second tuner and the second demodulator, a third scan use second channel list indicating channels identified as channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present, and at least one of the first controller and the second controller executes a channel scan in the third broadcast protocol on the channels indicated in the third scan use first channel list and the third scan use second channel list. - View Dependent Claims (10)
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11. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol, a second broadcast protocol, and a third broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal; a first demultiplexer for separating first data including tuning information from the first digital signal; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing channel scans in the first broadcast protocol and the third broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal; a second demultiplexer for separating second data including tuning information from the second digital signal; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing channel scans in the second broadcast protocol and the third broadcast protocol;
whereinthe first controller and the second controller divide between them a plurality of channels included in one of the frequency bands of the first broadcast protocol, the second broadcast protocol, and the third broadcast protocol and execute channel scans in parallel in the third broadcast protocol as a first phase channel scan; in the first phase channel scan, the first controller executes a channel scan in the third broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use first channel list indicating channels in which a broadcast wave not belonging to the third broadcast protocol is likely to be present, and in the first phase channel scan, the second controller executes a channel scan in the third broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use first channel list indicating channels in which a broadcast wave not belonging to the third broadcast protocol is likely to be present; and as a second phase channel scan, the first controller executes a channel scan in the first broadcast protocol on the channels indicated in the first scan use first channel list, and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use second channel list indicating channels identified as channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, and the second controller executes a channel scan in the second broadcast protocol on the channels indicated in the second scan use first channel list, and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use second channel list indicating channels identified as channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; and as a third-phase channel scan, the first controller executes the channel scan in the first broadcast protocol on the channels indicated in the second scan use second channel list, and the second controller executes the channel scan in the second broadcast protocol on the channels indicated in the first scan use second channel list. - View Dependent Claims (12)
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13. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol, a second broadcast protocol, a third broadcast protocol, and a fourth broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal; a first demultiplexer for separating third data and first data including tuning information from the first digital signal; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing channel scans in the first broadcast protocol and the third broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal; a second demultiplexer for separating third data and second data including tuning information from the second digital signal; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing channel scans in the second broadcast protocol and the fourth broadcast protocol;
whereinthe first controller and the second controller divide between them a plurality of channels included in the overlapping frequency bands of the first broadcast protocol, the second broadcast protocol, the third broadcast protocol, and the fourth broadcast protocol and execute a channel scan in the first broadcast protocol and a channel scan in the second broadcast protocol in parallel as a first phase channel scan; in the first phase channel scan, the first controller executes the channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use first channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, and in the first phase channel scan, the second controller executes the channel scan in the second broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use first channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; as a second phase channel scan, the first controller executes a channel scan in the first broadcast protocol on the channels indicated in the second scan use first channel list, and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use second channel list indicating channels identified as channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, and the second controller executes a channel scan in the second broadcast protocol on the channels indicated in the first scan use first channel list, and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use second channel list indicating channels identified as channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; as a third-phase channel scan, the first controller executes a channel scan in the third broadcast protocol on the channels indicated in the second scan use second channel list, and generates, from information indicating reception status from the first tuner and the first demodulator, a third scan use channel list indicating channels identified as channels in which a broadcast wave not belonging to the third broadcast protocol is likely to be present, and the second controller executes a channel scan in the fourth broadcast protocol on the channels indicated in the first scan use second channel list, and generates, from information indicating reception status from the second tuner and the second demodulator, a fourth scan use channel list indicating channels identified as channels in which a broadcast wave not belonging to the fourth broadcast protocol is likely to be present; and as a fourth-phase channel scan, the first controller executes a channel scan in the third broadcast protocol on the channels indicated in the fourth scan use channel list, and the second controller executes a channel scan in the fourth broadcast protocol on the channels indicated in the third scan use channel list.
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14. A digital broadcast receiver for receiving broadcasts in a first broadcast protocol, a second broadcast protocol, a third broadcast protocol, and a fourth broadcast protocol that use a plurality of frequency bands in which at least one or more frequency bands are overlapping frequency bands, the digital broadcast receiver comprising:
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a first tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a first demodulator for demodulating the electrical signal obtained from the first tuner and generating a first digital signal; a first demultiplexer for separating third data and first data including tuning information from the first digital signal; a first controller for controlling the first tuner, the first demodulator, and the first demultiplexer and executing channel scans in the first broadcast protocol and the third broadcast protocol; a second tuner for receiving an electromagnetic wave and generating an electrical signal from the electromagnetic wave; a second demodulator for demodulating the electrical signal obtained from the second tuner and generating a second digital signal; a second demultiplexer for separating third data and second data including tuning information from the second digital signal; and a second controller for controlling the second tuner, the second demodulator, and the second demultiplexer and executing channel scans in the second broadcast protocol and the fourth broadcast protocol;
whereinthe first controller and the second controller divide between them a plurality of channels included in the overlapping frequency bands of the first broadcast protocol, the second broadcast protocol, the third broadcast protocol, and the fourth broadcast protocol and execute a channel scan in the first broadcast protocol and a channel scan in the second broadcast protocol in parallel as a first phase channel scan; in the first phase channel scan, the first controller executes a channel scan in the first broadcast protocol and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use first channel list indicating channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, and in the first phase channel scan, the second controller executes a channel scan in the second broadcast protocol and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use first channel list indicating channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; as a second phase channel scan, the first controller executes a channel scan in the first broadcast protocol on the channels indicated in the second scan use first channel list, and generates, from information indicating reception status from the first tuner and the first demodulator, a first scan use second channel list indicating channels identified as channels in which a broadcast wave not belonging to the first broadcast protocol is likely to be present, and the second controller executes a channel scan in the second broadcast protocol on the channels indicated in the first scan use first channel list, and generates, from information indicating reception status from the second tuner and the second demodulator, a second scan use second channel list indicating channels identified as channels in which a broadcast wave not belonging to the second broadcast protocol is likely to be present; as a third-phase channel scan, the first controller executes a channel scan in the third broadcast protocol on the channels indicated in the second scan use second channel list, and generates, from information indicating reception status from the first tuner and the first demodulator, a third scan use channel list indicating channels identified as channels in which a broadcast wave not belonging to the third broadcast protocol is likely to be present, and the second controller executes a channel scan in the third broadcast protocol on the channels indicated in the first scan use second channel list, and generates, from information indicating reception status from the second tuner and the second demodulator, a fourth scan use channel list indicating channels identified as channels in which a broadcast wave not belonging to the third broadcast protocol is likely to be present; and as a fourth-phase channel scan, the first controller executes a channel scan in the fourth broadcast protocol on the channels indicated in the fourth scan use channel list, and the second controller executes a channel scan in the fourth broadcast protocol on the channels indicated in the third scan use channel list.
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Specification