JP4883130B2 - Mobile digital broadcast receiver - Google Patents

Description

  The present invention relates to a mobile digital broadcast receiver and a channel search method in the mobile digital broadcast receiver, and more specifically, a mobile digital broadcast receiver and a mobile digital broadcast receiver capable of speeding up channel search. Relates to a channel search method.

In digital broadcasting, there are multiple service forms such as a service including high-definition video and audio (hereinafter referred to as full segment) and a service with a wide reception area (hereinafter referred to as one-segment) while being low-quality video and audio. .
In the broadcast receiving apparatus corresponding to the plurality of service forms, when the electric field strength of a physical channel in a certain service form is lower than a predetermined reception level threshold, the broadcast receiving apparatus that switches to reception of the same physical channel in another service is provided. Yes (see, for example, Patent Document 1).

JP 2001-111642 A

However, in the conventional broadcast receiving apparatus, there is a problem in that, when viewing a full segment, if a channel search is performed at a level at which one segment can be received and a viewable channel is determined, it becomes a state where it cannot be substantially viewed. there were.
That is, when channel search is performed for the relay station in the conventional broadcast receiving apparatus and the predetermined reception level threshold is set to a low reception level, channel selection is performed as a result of channel search during full segment viewing. There was a problem that it could be received but not actually received. In addition, when the above-described conventional broadcast receiving apparatus performs a channel search for a relay station and a predetermined reception level threshold is set to a high reception level, there is a problem in that the channel search is not completed during one-segment viewing. there were.
In addition, there is a problem that a flexible response according to the type of broadcasting station such as a relay station or affiliated station is not possible.
The present invention has been made to solve the above-described problems, and can search for a relay station preferentially in a plurality of reception service modes, and can realize channel search at high speed and accurately with an inexpensive configuration. It is an object of the present invention to provide a mobile digital broadcast receiving apparatus capable of performing the same and a channel search method in the mobile digital broadcast receiving apparatus.

  The mobile digital broadcast receiving apparatus of the present invention receives a channel selection request, selects a physical channel designated by the channel selection request, and a reception level for measuring the electric field strength of the selected physical channel. Based on the measurement unit, at least the storage unit for storing the current reception level threshold, the reception level threshold information and the channel search list, the threshold determination unit for determining the current reception level threshold, and the stored channel search list, A search processing unit that executes a channel search process, and the threshold determination unit extracts a corresponding reception level threshold from the reception level threshold information according to the current reception mode and switching mode, and the storage unit stores it The current reception level threshold is updated with the extracted reception level threshold, and the search processing unit updates the stored current reception level threshold and the measured electric field strength. Zui, a tuner determines receivability of the physical channel selected, it is characterized.

  The channel search method in the mobile digital broadcast receiver of the present invention includes a step of storing reception level threshold information, a step of receiving a channel selection request, and selecting a physical channel designated by the channel selection request; A receiving mode and a switching mode, a step of acquiring a corresponding receiving level threshold from receiving level threshold information based on the acquired current receiving mode and switching mode, and a corresponding receiving level threshold and channel selection. And determining whether the physical channel can be received according to the electric field strength of the physical channel.

As described above, according to the present invention, a plurality of reception level thresholds at the time of channel search execution are set according to the viewing mode and the switching mode, and the reception level threshold is set so that the relay station can preferentially select a channel. Therefore, it is possible to select a relay station preferentially over affiliated stations without performing channel search for all receivable physical channels, and channel search can be realized at high speed with an inexpensive configuration.

1 is a block diagram showing the configuration of a mobile digital broadcast receiver according to a first embodiment of the present invention. Flowchart showing channel search processing according to the embodiment The figure which shows the reception level threshold value information concerning the embodiment

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a mobile digital broadcast receiving apparatus according to Embodiment 1 of the present invention. The mobile digital broadcast receiving apparatus 100 is a digital broadcast receiving apparatus installed in a moving body such as a vehicle, for example, and includes a channel selection unit 101, a reception level measurement unit 102, a storage unit 103, a threshold determination unit 104, The search processing unit 105 is configured.

  The channel selection unit 101 tunes to the instructed physical channel in response to a channel selection request from the search processing unit 105.

  The reception level measurement unit 102 measures the radio field intensity of the physical channel selected by the channel selection unit 101 and outputs the measured radio field intensity information to the search processing unit 105 as radio field intensity information.

  The storage unit 103 stores reception level threshold information and a current reception level threshold. The channel search list, the current viewing mode, and the switching mode are stored. Here, the viewing mode is a state where a full segment or one segment is being viewed, and either one can be selected. The switching mode represents one of a state in which only full seg is received, a state in which only one seg is received, and a state in which full seg and one seg are automatically switched according to the reception state, and can be designated by the user. is there.

  In response to a threshold determination request from the search processing unit 105, the threshold determination unit 104 acquires the current viewing mode, switching mode, and reception level threshold information from the storage unit 103, and determines the current reception level threshold. Then, the determined current reception level threshold value is output to the storage unit 103. The reception level threshold setting process will be described in detail later with reference to FIG.

  The search processing unit 105 outputs a threshold determination request to the threshold determination unit 104, triggered by a channel search instruction from the user or detection of a decrease in radio wave intensity of the broadcast channel being viewed. Further, based on the current reception level threshold acquired from the storage unit 103 and the radio wave intensity information acquired from the reception level measurement unit 102, it is determined whether or not the selected physical channel can be received. If reception is possible, reception of the physical channel for which the channel selection instruction has been issued is continued. The search process will be described in detail later with reference to FIG.

  Next, channel search processing executed by the threshold determination unit 104 and the search processing unit 105 will be described with reference to FIGS. FIG. 2 is a flowchart showing channel search processing according to the first exemplary embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration of reception level threshold information. The channel search process includes a reception level threshold setting process (step S202 to step S205) executed by the threshold determination unit 104 and a search process (step S201, step S206, step S207) executed by the search processing unit 105.

  First, the search processing unit 105 uses the channel search instruction from the user or detection of a decrease in radio wave intensity of the broadcast channel being viewed as a trigger to request the channel selection unit 101 to select a channel based on the channel search list stored in the storage unit 103. Is output. Further, a threshold determination request is output to the threshold determination unit 104 (step S201).

  When receiving a threshold determination request from the search processing unit 105, the threshold determination unit 104 acquires the reception level threshold information, the current viewing mode, and the switching mode from the storage unit 103, and specifies the current viewing mode (step S202). ). If the current viewing mode is full segment (“YES” in step S202), a reception level threshold corresponding to the full segment switching mode is extracted from the reception level threshold information (step S203), and the extracted reception level threshold is stored in the storage unit. To 103.

  On the other hand, when the current viewing mode is one-segment (“NO” in step S202), a reception level threshold corresponding to the one-segment switching mode is extracted from the reception level threshold information (step S204), and the extracted reception level threshold is set. The data is output to the storage unit 103.

  The storage unit 103 updates the current reception level threshold with the reception level threshold acquired from the threshold determination unit 104 (step S205).

  After the above processing, the search processing unit 105 is a level at which the physical channel that has made the channel selection request can be received based on the current reception level threshold acquired from the storage unit 103 and the electric field strength information acquired from the reception level measurement unit 102. If it is determined that the level is receivable ("YES" in step S206), reception of the detected physical channel is continued (step S207).

  On the other hand, if the search processing unit 105 determines that the physical channel for which the channel selection request has been made is not at a receivable level (“NO” in step S206), the channel selection request for the next physical channel described in the channel search list is requested. Is output to the channel selection unit 101, and the processing from step S201 to step S206 is repeated until a receivable level physical channel is detected.

  Note that the channel search list may be a list in which all receivable physical channels are arranged in order from the lowest frequency, or a list in which the frequencies are arranged in order from the lowest frequency for each broadcast type. However, in order to preferentially select a relay station, a channel search using a relay station list transmitted as a digital broadcast signal is first performed as a broadcast type, and then a channel search for the remaining receivable physical channels is performed. It is desirable to do.

  In the embodiment of the present invention, as shown in FIG. 3, the reception level thresholds are set to “high”, “medium”, and “low” according to the current viewing mode and switching mode. Depending on the broadcast type search of the search / affiliated station search, the reception level threshold may be further subdivided even if the reception level threshold is the same. For example, the reception level threshold may be “high (30)”, “high (30)” for relay station search, and “high (40)” for affiliate station search.

  Further, in the embodiment of the present invention, when the threshold determination unit 104 receives a threshold determination request from the search processing unit 105, the threshold determination unit 104 acquires a reception level threshold corresponding to the current viewing mode from the reception level threshold information ( In step S202, step S203, step S204), the current reception level threshold is updated with the acquired reception level threshold (step S205), but when the threshold determination request is received, the current viewing mode is not determined. All the reception level threshold values may be acquired from the reception level threshold value information to update the current reception level threshold value.

  According to the present invention, the reception level threshold value is changed according to the current reception mode, broadcast type, and switching mode to determine whether or not reception is possible at the time of channel search. Search time can also be shortened.

  In addition, it is not necessary to add a new configuration (for example, providing a separate dedicated tuner) for speeding up the channel search process, and the channel search processing can be speeded up with the conventional one tuner configuration. Can do.

  According to the present invention, at the time of channel search execution, the reception level threshold is changed according to the reception situation to search for the relay station preferentially, and the channel search can be realized quickly and accurately with an inexpensive configuration. For example, it is useful for all mobile digital broadcast receivers such as a vehicle-mounted digital broadcast receiver and a portable digital broadcast receiver.

DESCRIPTION OF SYMBOLS 100 Mobile digital broadcast receiver 101 Channel selection part 102 Reception level measurement part 103 Storage part 104 Threshold judgment part 105 Search processing part

Claims (1)

A channel selection unit that selects a physical channel instructed by a channel selection request from a search processing unit described later;
A reception level measurement unit that measures the electric field strength of the physical channel selected by the channel selection unit;
When a threshold determination request is received from a search processing unit (to be described later), reception level threshold information having a plurality of reception level thresholds depending on the broadcast station type for distinguishing between a relay station and an affiliated station, the current reception is a high quality service and a low quality A storage unit which will be described later showing a current viewing mode indicating which of the services, and a switching mode indicating whether the high-quality service fixed, the low-quality service fixed, or the high-quality service low-quality service automatic switching specified by the user And a threshold value determination unit that extracts a reception level threshold value corresponding to the current viewing mode and switching mode from the reception level threshold value information;
Selects physical channels described in the channel search list including a list in which all physical channels that can be received for each broadcast station type and are stored in the storage unit described later are arranged in order from the lowest frequency, and are stored in the storage unit described later A search processing unit that determines whether or not the channel selected by the channel selection unit can be received based on the current reception level threshold value and the electric field strength measured by the reception level measurement unit;
The current reception level threshold value, the current viewing mode, the switching mode, the reception level threshold value information, and the channel search list are stored, and the current reception level threshold value is determined by the reception level threshold value extracted by the threshold value determination unit. A storage unit to be updated;
A mobile digital broadcast receiving apparatus.

Images