JP5355258B2 - Digital broadcast receiving apparatus and digital broadcast receiving method - Google Patents

Description

  The present invention relates to a digital broadcast receiving apparatus and a digital broadcast receiving method, and more particularly to a digital broadcast receiving apparatus and a digital broadcast receiving method mounted on a mobile body such as a vehicle and a mobile terminal device.

  The digital broadcast signal is transmitted with a broadcast wave having a different frequency for each broadcast station, and a physical channel (hereinafter, simply referred to as “channel”) is different for each broadcast station. Also, parameters such as transport stream ID (abbreviation: Ts_ID) are different for each broadcasting station. Hereinafter, information such as physical channels and Ts_ID necessary for selecting a digital broadcast is collectively referred to as “channel information”, and a table for managing this channel information for all receivable channels is referred to as “terrestrial information”. Network table ".

  The area where a digital broadcast signal transmitted from a broadcast station can be received by the digital broadcast receiver is limited to the vicinity of the broadcast relay station that relays the broadcast wave of the digital broadcast signal transmitted from the broadcast station. The channel information of broadcast signals varies from region to region.

  Therefore, when a digital broadcast signal is received by a digital broadcast receiver mounted on a mobile body, the digital broadcast signal may not be received on a channel that has been received until then, as the mobile body moves. In order to be able to receive digital broadcast signals again, all physical channels are scanned and channel information of digital broadcast signals that can be received is acquired again, and a new terrestrial network table is created, or It is necessary to search in ascending order from the smallest physical channel to find a physical channel that can receive a digital broadcast signal.

  However, in the method of scanning all physical channels and the method of searching in ascending order from the physical channel with the smallest channel number, scanning or searching is also performed for physical channels that cannot receive digital broadcast signals in the current location of the digital broadcast receiver. Therefore, there is a problem that it takes a long time before the digital broadcast signal can be received again.

  As a technique for solving this problem, a list of channel information of digital broadcast signals that can be received for each region (hereinafter referred to as “channel information list for each region”) is stored, and a position that represents the current position of the digital broadcast receiver A technique for automatically acquiring channel information of a digital broadcast signal that can be received at the position based on the information has been proposed (see, for example, Patent Documents 1 and 2).

  The broadcast receiver disclosed in Patent Document 1 sets a channel based on channel information if the channel information of the region corresponding to the current position is stored in the channel list corresponding to the channel information list for each region. To do. If the channel information of the region corresponding to the current position is not saved in the channel list, all physical channels are scanned to obtain channel information that can be acquired at the current position, and the channel is set based on the information. , Save the information in the channel list.

  The receiving device disclosed in Patent Literature 2 stores a table corresponding to the regional channel information list, acquires a regional table corresponding to the current position, and channels of all channel information included in the acquired table If the channel can be received, the channel is set as it is. If the channel cannot be received, the channel information of the channel is replaced with the channel information of the adjacent region, and the channel of the channel information of the adjacent region is selected. To do.

JP 2008-124718 A JP 2008-206032 A

  In the broadcast receiver disclosed in Patent Document 1, the reception status of a digital broadcast signal changes between when a channel list is created and when channel information is acquired from the channel list based on the current position. There is a possibility that a channel that cannot be received is set or a channel that can be received is not set.

  Also, when the physical channel of a digital broadcast signal transmitted from a broadcast station changes or when a broadcast wave of a digital broadcast signal from a new broadcast station can be received, the channel of the digital broadcast signal is set There is a risk that it cannot be done.

  In the broadcast receiver disclosed in Patent Document 1, all physical channels are scanned at the current position, channel information that can be acquired at the current position is acquired, and stored in the channel list. Therefore, when the digital broadcast receiver moves to an area where it has never moved, there is no channel information corresponding to that area, so it is necessary to scan all physical channels, and to acquire the channel information. May take time.

  In the receiving apparatus disclosed in Patent Document 2, when reception is impossible in both the channel information channel acquired based on the current position and the channel information channel in the adjacent area, a reception disabled channel is set. There is a fear.

  Further, Patent Document 2 does not describe a case where there is no channel information in a region corresponding to the current position. Further, in the receiving device disclosed in Patent Document 2, since channel information for each region is not updated, when a physical channel of a digital broadcast signal transmitted from a broadcasting station changes or from a new broadcasting station When a broadcast wave of a digital broadcast signal can be received, there is a possibility that the channel of the digital broadcast signal cannot be set.

  An object of the present invention is to provide a digital broadcast receiving apparatus capable of setting a receivable broadcast service channel in as short a time as possible when a broadcast service of a digital broadcast signal cannot be received due to movement. It is to provide a digital broadcast receiving method.

The digital broadcast receiving apparatus of the present invention selects a physical channel, extracts a digital broadcast signal transmitted by the selected physical channel, and a digital broadcast signal acquired by the tuner unit. A signal extraction unit for extracting a signal of a broadcast service, a signal output unit for outputting a signal of the broadcast service extracted by the signal extraction unit, information indicating a specific area, a name of the broadcast service, and the physical channel Information, an area information storage unit that stores adjacent area information including information representing an area adjacent to the specific area, the specific area, and a physical channel through which a digital broadcast signal receivable in the area is transmitted a channel information storage unit for storing a table including the channel information that associates, before Symbol the broadcast service received by a mobile inter-regional When changing from potential state to the Not Ready state, in the destination area, searching by the search for the broadcast service of the same broadcasting service, from the time when the broadcast service is unreceivable state, the broadcast service identical to the obtains an elapsed time until the time the broadcast service can be received by the search, the elapsed time is judged to be less than the predetermined threshold value, before and the source region was located at the time of the reception state The destination area is registered in the adjacent area information as areas adjacent to each other , and among the tables stored in the channel information storage section, the area registered in the adjacent area information is registered with the tuner section. A channel selection control unit that selects a physical channel included in the table is provided .

The digital broadcast receiver of the present invention selects a physical channel, extracts a digital broadcast signal transmitted on the selected physical channel, and a digital broadcast signal acquired by the tuner unit. A signal extraction unit for extracting a signal of the broadcast service to be performed, a signal output unit for outputting the signal of the broadcast service extracted by the signal extraction unit, information representing a specific area, the name of the broadcast service, the physical channel of information, said the specific area information storage unit that stores the adjacent area information includes information indicating an area adjacent to the region, said a particular region, the physical channel that can be received digital broadcast signal is transmitted in the region a channel information storage unit for storing a table including the channel information that associates bets, the broadcast service by the movement between the prior SL Region When it changed to Not Ready state from Shin state, in the destination area, searching by the search for the broadcast service of the same broadcasting service, from the time when the broadcast service is unreceivable state, identical to the broadcast service obtains the moving distance up to the point where the broadcast service is receivable by the search, the moving distance is judged to be less than the predetermined threshold value, and the source region was located at the time of the reception state registered in the neighboring area information and area before Symbol destination as the adjacent regions to each other, to the tuner section, among the channel information storage unit in the stored table, which is registered in the adjacent area information region And a channel selection control unit for selecting a physical channel included in the table .

The digital broadcast receiving method of the present invention selects a physical channel, selects a physical channel, acquires a digital broadcast signal transmitted on the selected physical channel, and extracts from the digital broadcast signal acquired in the tuner step. A signal extraction step of extracting a signal of the broadcast service to be performed, a signal output step of outputting the signal of the broadcast service extracted in the signal extraction step, information representing a specific area, the name of the broadcast service, the physical channel of information, said the specific area information storage step of storing the adjacent area information includes information indicating an area adjacent to the region, said a particular region, the physical channel that can be received digital broadcast signal is transmitted in the region a channel information storage step of storing a table including the channel information correlating bets, When the broadcasting service by the movement between the serial area is changed from the receive state to the Ready state, in the destination area, the same broadcast service and the broadcast service is retrieved by the search, the broadcast service is unreceivable state When the elapsed time from the point in time until the point when the same broadcast service as the broadcast service becomes receivable by the search is determined and it is determined that the elapsed time is equal to or less than a predetermined threshold, and the adjacent region and the source region was located before Symbol destination region to one another to register before Symbol adjacent area information, to the tuner step, stored in the channel information storing step table Among these, the channel selection control step for selecting a physical channel included in the region table registered in the adjacent region information. Characterized in that it comprises and.

The digital broadcast receiving method of the present invention selects a physical channel, selects a physical channel, acquires a digital broadcast signal transmitted on the selected physical channel, and extracts from the digital broadcast signal acquired in the tuner step. A signal extraction step of extracting a signal of the broadcast service to be performed, a signal output step of outputting the signal of the broadcast service extracted in the signal extraction step, information representing a specific area, the name of the broadcast service, the physical channel of information, said the specific area information storage step of storing the adjacent area information includes information indicating an area adjacent to the region, said a particular region, the physical channel that can be received digital broadcast signal is transmitted in the region a channel information storage step you store a table including the channel information that associates bets, When the broadcasting service by the movement between the serial area is changed from the receive state to the Ready state, in the destination area, the same broadcast service and the broadcast service is retrieved by the search, the broadcast service is unreceivable state When the movement distance from the point in time until the point at which the same broadcast service as the broadcast service becomes receivable by the search is determined and it is determined that the movement distance is equal to or less than a predetermined threshold, and the adjacent region and the source region was located before Symbol destination region to one another to register before Symbol adjacent area information, to the tuner step, stored in the channel information storing step table Among these, the channel selection control step for selecting a physical channel included in the region table registered in the adjacent region information. Characterized in that it comprises and.

According to the digital broadcast receiving apparatus of the present invention, a physical channel is tuned by Chi Yuna section, the digital broadcast signal transmitted on the physical channels is obtained from the digital broadcast signal, the broadcast service signal extractor The signal is extracted and output by the signal output unit. The area information storage unit stores information indicating a specific region, the name of a broadcast service, information on a physical channel, and adjacent region information including information indicating a region adjacent to the specific region . A table including channel information in which a specific area is associated with a physical channel through which a digital broadcast signal receivable in that area is transmitted is stored. When the broadcast service changes from the receivable state to the unreceivable state due to movement between regions, the channel selection control unit searches for the same broadcast service as that broadcast service in the destination region .

Then, the elapsed time from the time when the broadcast service becomes unreceivable until the time when the same broadcast service as the broadcast service becomes receivable by search is obtained, and if the elapsed time is less than the threshold value, reception is possible. The source area and the destination area that were located in the state are registered in the adjacent area information as areas adjacent to each other.

  As a result, the channel selection control unit can preferentially search a physical channel that may be received based on channel information of an area registered as an area adjacent to the adjacent area information at the next search. it can. Therefore, a receivable broadcast service channel can be set in as short a time as possible.

According to the digital broadcast receiving apparatus of the present invention, a physical channel is tuned by Chi Yuna unit, broadcasting the digital broadcast signal transmitted on the physical channels is obtained from the digital broadcast signal, the signal extraction unit Service Are extracted and output by the signal output unit. The area information storage unit stores information indicating a specific region, the name of a broadcast service, information on a physical channel, and adjacent region information including information indicating a region adjacent to the specific region . A table including channel information in which a specific area is associated with a physical channel through which a digital broadcast signal receivable in that area is transmitted is stored. When the broadcast service changes from the receivable state to the unreceivable state due to movement between regions, the channel selection control unit searches for the same broadcast service as that broadcast service in the destination region .

Then, the travel distance from the time when the broadcast service becomes unreceivable until the time when the same broadcast service as the broadcast service can be received by search is obtained, and if the travel distance is less than the threshold, reception is possible. The source area and the destination area that were located in the state are registered in the adjacent area information as areas adjacent to each other.

  As a result, the channel selection control unit can preferentially search a physical channel that may be received based on channel information of an area registered as an area adjacent to the adjacent area information at the next search. it can. Therefore, a receivable broadcast service channel can be set in as short a time as possible.

According to the digital broadcast receiving method of the present invention, the physical channel is tuned by Chi Yunasuteppu, the digital broadcast signal transmitted on the physical channels is obtained from the digital broadcast signal, the broadcast service in signal extraction step A signal is extracted and output in a signal output step. In the area information storing step, adjacent area information including information indicating a specific area, broadcast service name, physical channel information, and information indicating an area adjacent to the specific area is stored. In the channel information storing step, a specific area is stored . A table including channel information in which a region and a physical channel through which a digital broadcast signal receivable in that region is transmitted is associated is stored. When the broadcast service changes from the receivable state to the unreceivable state due to movement between regions, the same broadcast service as that broadcast service is searched in the channel selection control step in the destination region .

Then, the elapsed time from the time when the broadcast service becomes unreceivable until the time when the same broadcast service as the broadcast service becomes receivable by search is obtained, and if the elapsed time is less than the threshold value, reception is possible. and the source region was located in the state and the destination area is registered in the neighbor region information in the adjacent area to one another.

  Thus, when the next search is performed in the channel selection control step, a physical channel that may be received can be preferentially searched based on channel information of an area registered as an area adjacent to the adjacent area information. it can. Therefore, a receivable broadcast service channel can be set in as short a time as possible.

According to the digital broadcast receiving method of the present invention, the physical channel is tuned by Chi Yunasuteppu, the digital broadcast signal transmitted on the physical channels is obtained from the digital broadcast signal, the broadcast service in signal extraction step A signal is extracted and output in a signal output step. In the area information storing step, adjacent area information including information indicating a specific area, broadcast service name, physical channel information, and information indicating an area adjacent to the specific area is stored. In the channel information storing step, a specific area is stored . Channel information that associates a region with a physical channel through which a digital broadcast signal that can be received in the region is transmitted is stored. When the broadcast service changes from the receivable state to the unreceivable state due to movement between regions, the same broadcast service as that broadcast service is searched in the channel selection control step in the destination region .

Then, the travel distance from the time when the broadcast service becomes unreceivable until the time when the same broadcast service as the broadcast service can be received by search is obtained, and if the travel distance is less than the threshold, reception is possible. and the source region was located in the state and the destination area is registered in the neighbor region information in the adjacent area to one another.

  Thus, when the next search is performed in the channel selection control step, a physical channel that may be received can be preferentially searched based on channel information of an area registered as an area adjacent to the adjacent area information. it can. Therefore, a receivable broadcast service channel can be set in as short a time as possible.

It is a block diagram which shows the structure of the digital broadcast receiver 1 which is the 1st Embodiment of this invention. A mobile unit equipped with the digital broadcast receiver 1 is a first region A to a second region B, a second region B to a third region C, a third region C to a fourth region D, and a fourth region D to a first region. It is a figure which shows a mode that it moves to A in order. 3 is a diagram illustrating an example of a terrestrial network table 30 in a first area A stored in a channel information storage unit 9. FIG. It is a figure which shows an example of the ground network table 31 in the 2nd area B memorize | stored in the channel information storage part. It is a graph which shows the relationship between the reception condition and elapsed time in each area of the same service in the 1st Embodiment of this invention. It is a figure which shows the adjacent area table 32 memorize | stored in the area information storage part 10 in the 1st Embodiment of this invention. It is a flowchart which shows the process sequence of the channel selection control part 8 regarding the search operation | movement of the same service of the digital broadcast receiver 1 in the 1st Embodiment of this invention. It is a flowchart which shows the process sequence of the channel selection control part 8 regarding the search operation | movement of the same service of the digital broadcast receiver 1 in the 1st Embodiment of this invention. It is a graph which shows the relationship between the reception condition in each area of the same service in the 2nd Embodiment of this invention, and the movement distance of the digital broadcast receiver. It is a figure which shows the adjacent area table 33 memorize | stored in the area information storage part 10 in the 2nd Embodiment of this invention. It is a flowchart which shows the process sequence of the channel selection control part 8 regarding the search operation | movement of the same service of the digital broadcast receiver 1 in the 2nd Embodiment of this invention. It is a flowchart which shows the process sequence of the channel selection control part 8 regarding the search operation | movement of the same service of the digital broadcast receiver 1 in the 2nd Embodiment of this invention.

<First Embodiment>
FIG. 1 is a block diagram showing a configuration of a digital broadcast receiving apparatus 1 according to the first embodiment of the present invention. The digital broadcast receiving apparatus 1 includes an antenna 2, a tuner unit 3, a demodulation unit 4, a demultiplexer 5, a decoder 6, a back end unit 7, an AV (Audio Visual) input / output interface 12, and a remote control light receiving unit. 13. The back end unit 7 includes a channel selection control unit 8, a channel information storage unit 9, an area information storage unit 10, and a meter information acquisition unit 11.

  The antenna 2 can receive a digital broadcast signal transmitted from a broadcast station. In the present embodiment, the digital broadcast receiving apparatus 1 includes two antennas 2 and performs a receiving operation using a diversity method. Specifically, the digital broadcast receiving apparatus 1 selects an antenna 2 having a good reception state from the two antennas 2 based on the intensity of the digital broadcast signal received by each antenna 2, and the selected antenna 2 uses the selected antenna 2. The received digital broadcast signal is given to the tuner unit 3.

  The tuner unit 3 extracts a signal having a specific frequency from the digital broadcast signal given from the antenna 2. Which frequency signal of the digital broadcast signal provided from the antenna 2 is extracted by the tuner unit 3 is controlled by the channel selection control unit 8 of the back-end unit 7 described later. In other words, the tuner unit 3 extracts the signal of the specific frequency based on the predetermined control signal given from the channel selection control unit 8. The specific frequency is a frequency of any one of a plurality of physical channels (hereinafter, simply referred to as “channel”) included in the digital broadcast signal, and the signal of the specific frequency is extracted. Means to select a channel. Selecting a channel by the tuner unit 3 and acquiring a digital broadcast signal transmitted through the selected channel corresponds to a tuner step.

  The tuner unit 3 gives the selected channel signal to the demodulation unit 4. The tuner unit 3 outputs reception level information indicating the reception strength of the signal of the selected channel. The reception level information output from the tuner unit 3 is given to the channel selection control unit 8 of the back end unit 7.

  The demodulation unit 4 performs demodulation and error correction of the signal given from the tuner unit 3 and outputs a transport stream (abbreviation: TS). The TS output from the demodulator 4 is given to the demultiplexer 5. Further, the demodulator 4 receives various signals such as reception C / N ratio (Carrier to Noise ratio) information, PLL (Phase Locked Loop) lock information, frame lock information, and error rate information of the signal provided from the tuner unit 3. At least one of them is output to the channel selection control unit 8 of the back end unit 7.

  The reception C / N ratio information is an index indicating how much noise is received with respect to the received carrier wave, that is, how much noise is present. The value of the reception C / N ratio is small if the noise is large. If the noise is small, it is large. Here, the carrier wave refers to video information and audio information of a program (hereinafter may be collectively referred to as “video / audio information”), and service information (Service Information; abbreviated as SI) which is program arrangement information described later. It is a radio wave signal that transmits information.

  The PLL is a frequency control circuit in which the local oscillation frequency is changed by the magnitude of the shift in order to correct the shift between the center frequency of the reception bandwidth and the frequency of the received radio wave in the carrier wave reception system. When the local oscillation frequency is changed by the magnitude of the shift by the PLL, that is, when locked, PLL lock information is output.

  A frame is one frame of an image. When there are video and audio streams in the received channel, these are locked and TS packets are given to the demultiplexer 5 and the decoder 6. When the frame is locked, frame lock information is output.

  The error rate refers to the data of the code error for all data when a code error occurs in the data due to the deterioration of the radio wave reception status or the error in demodulation in the TS stream consisting of continuous video and audio TS packets. It is a ratio. Information representing this ratio is error rate information. There are two types of errors: “random errors” in which errors occur sporadically and “burst errors” in which many errors are concentrated in a short interval. For video and audio information that appeals to human sense, even if there are some errors such as random errors, it does not matter, but since it is a problem for burst errors, the code order is changed and the section where burst errors are short A technique called interleaving is used so as not to concentrate on the.

  The demultiplexer 5 extracts program specific information (abbreviation: PSI) and SI from the TS given from the demodulator 4 and stores the extracted PSI and SI in a memory (not shown).

  The demultiplexer 5 uses at least one of the extracted PSI and SI, that is, PSI and / or SI (hereinafter also referred to as “PSI / SI”), and at least one of video TS packets and audio TS packets in the TS. One type of TS packet identifier (abbreviation: PID) value is detected, TS is filtered by each PID, and a signal of a broadcast service to be extracted (hereinafter simply referred to as “service”), specifically Specifically, the video TS packet and the audio TS packet are separated and extracted. The demultiplexer 5 corresponds to a signal extraction unit. Extracting a broadcast service signal to be extracted from the TS by the demultiplexer 5 corresponds to a signal extraction step.

  In the present embodiment, the video format included in the video TS packet and the audio format included in the audio TS packet are MPEG-2 (Moving Picture Experts Group phase 2). The format of the video included in the video TS packet is not limited to MPEG-2. In other embodiments of the present invention, MPEG (Moving Picture Experts Group) 2-video may be used, or MPEG4-AVC (Advanced Video Coding). ) Or other types of video. The audio format included in the audio TS packet is not limited to MPEG-2. In another embodiment of the present invention, MPEG2-BC (Backward Compatible) or MPEG2-AAC (Advanced Audio Coding) may be used. Alternatively, AC3 (Dolby AC3: Audio Code Number 3) may be used, or other types of audio may be used. A plurality of types of video TS packets and audio TS packets may be extracted simultaneously.

  The demultiplexer 5 provides the decoder 6 with at least one type of TS packet of the video TS packet and the audio TS packet. The demultiplexer 5 is a program association table (Program Association Table; abbreviated as PAT) disconnection information (hereinafter sometimes referred to as “PAT disruption information”), a program correspondence table (Program Map Table; abbreviated as PMT), which is a program integration table. Information (hereinafter also referred to as “PMT disruption information”), TS synchronization loss information (hereinafter also referred to as “TS synchronization lost information”), and TS packet loss information (hereinafter referred to as “TS packet lost information”) ) At least one of the various information.

  The broadcast wave is received by the tuner unit 3 and converted by the demodulation unit 4 into a stream composed of continuous TS packets. One TS packet includes a 4-byte TS header and a main body called a 184-byte payload. Even in a stream composed of continuous TS packets, TS packets are not necessarily continuous depending on the radio wave condition received by the tuner unit 3.

  TS sync lost information indicates that the TS sync byte (fixed with a value of 0x47) at the beginning of the TS header, which is the first 4 bytes of the TS packet, was not detected, that is, the TS packets were not taken continuously. Information indicating that the TS packet has been lost. The TS synchronization lost information is issued when no synchronization byte is detected every 188 bytes in the TS.

  The TS packet lost information is issued when it is detected that the continuous counter value existing in the TS header of the first 4 bytes of the TS packet is discontinuous. For example, if the continuous counter value of a certain TS packet is “169” and the continuous counter value of the next TS packet is “170”, these TS packets are continuous, but the continuous counter value of a certain TS packet is Is “169” and the continuous counter value of the next TS packet is “172”, these TS packets are not continuous.

  The PMT describes the PID of the TS packet that transmits each encoded signal constituting the program, and the PAT describes the PID of the TS packet that transmits this PMT. If at least one of PAT and PMT can be acquired, decoding of the video / audio signal is almost certain. The PAT disruption information is issued when the PAT cannot be received at a predetermined time interval, and the PMT disruption information is issued when the PMT cannot be received at a predetermined time interval.

  A TS may include a plurality of services. Which service of the services included in the TS is selected by the demultiplexer 5 is controlled by the channel selection control unit 8 described later. In other words, the demultiplexer 5 selects a service included in the TS based on a predetermined control signal given from the channel selection control unit 8.

  In this embodiment, the decoder 6 is realized by an MPEG-2 decoder. The decoder 6 is not limited to this, and is appropriately selected according to the video format included in the video TS packet and the audio format included in the audio TS packet.

  The decoder 6 decodes at least one type of TS packet out of the video TS packet and audio TS packet given from the demultiplexer 5. The decoder 6 outputs the decoded video signal of the video packet and the decoded audio signal of the audio packet to the video / audio output device 15 connected by the cable 14 via the AV input / output interface 12. The AV input / output interface 12 corresponds to a signal output unit. The video / audio output device 15 is realized by, for example, a television receiver. Decoding the broadcast service signal extracted and given by the demultiplexer 5 by the decoder 6 and outputting it by the AV input / output interface 12 corresponds to a signal output step.

  The decoder 6 outputs decoding error information when processing of at least one of the decoding of the video TS packet and the decoding of the audio TS packet becomes impossible. As the decoding error information, at least one of decoding error detection information indicating that a decoding error has been detected and decoding error rate information indicating a decoding error rate is output.

  The TS stream output from the demultiplexer 5 is encoded, that is, digital data subjected to code conversion according to a certain rule, and cannot be reproduced as it is. In order to reproduce it, the encoded data must be decoded. Here, the term “decoding” is a synonym of encoding and means decoding, and means that the encoded data is restored. At the time of decoding, the ratio of data decoded erroneously to the total data is the decoding error rate.

  The digital broadcast receiver 1 is configured to be capable of wireless communication with a remote controller (hereinafter referred to as “remote controller”) 16 by a remote control light receiving unit 13. When the remote control light receiving unit 13 receives the channel selection instruction transmitted by the user operating the remote control 16, the channel selection instruction is given to the back end unit 7, specifically, the channel selection control unit 8 of the back end unit 7. . The channel selection control unit 8 receives the channel selection instruction given from the remote control light receiving unit 13, acquires the channel information described in the terrestrial network table stored in the channel information storage unit 9 described later, and stores the channel information in the channel information. Based on the channel selection. Specifically, the channel selection control unit 8 instructs the tuner unit 3 on the physical channel to be selected based on the acquired channel information.

  When the digital broadcast receiving apparatus 1 is mounted on a mobile body such as a vehicle or carried by a user and used, the reception position of the digital broadcast receiving apparatus 1 moves as the mobile body or the user moves. As a result, the reception position may be outside the service area of the broadcasting station of the program being viewed, or may be affected by the blocking and attenuation of the carrier wave by the ground structure. In such a case, it becomes impossible to receive a digital broadcast signal from a broadcasting station that is broadcasting the program being viewed. In this way, the channel selection control unit 8 detects a state in which it is impossible to receive a digital broadcast signal from a broadcast station (hereinafter sometimes referred to as a “reception disabled state”).

  The channel selection control unit 8 detects that it is in a “reception impossible state” based on at least one of the various information output from the tuner unit 3, the demodulation unit 4, the demultiplexer 5, and the decoder 6. To do.

  For example, the channel selection control unit 8 detects that the reception is disabled based on the reception level information given from the tuner unit 3. Specifically, the channel selection control unit 8 determines that the reception is disabled when the reception level indicated by the reception level information is less than a predetermined threshold.

  Further, the channel selection control unit 8 detects that reception is not possible based on the reception C / N ratio information given from the demodulation unit 4, for example. Specifically, the channel selection control unit 8 determines that reception is not possible when the C / N ratio represented by the reception C / N ratio information is less than a predetermined threshold. For example, the channel selection control unit 8 determines that the reception is not possible when it is determined that the PLL lock has been released based on the PLL lock information provided from the demodulation unit 4. For example, the channel selection control unit 8 determines that the reception is disabled when it is determined that the frame lock has been released based on the frame lock information provided from the demodulation unit 4. Further, the channel selection control unit 8 detects that reception is not possible based on error rate information given from the demodulation unit 4, for example. Specifically, the channel selection control unit 8 determines that reception is disabled when the error rate exceeds a predetermined threshold.

  For example, the channel selection control unit 8 determines that the reception is disabled when it is determined that the PAT interruption is detected based on the PAT interruption information provided from the demultiplexer 5. For example, the channel selection control unit 8 determines that the reception is disabled when it is determined that the PMT interruption is detected based on the PMT interruption information given from the demultiplexer 5. For example, the channel selection control unit 8 determines that the reception is not possible when it is determined that the TS synchronization lost is detected based on the TS synchronization lost information provided from the demultiplexer 5. The channel selection control unit 8 determines that the reception is disabled when it is determined that the loss of the TS packet is detected based on the loss information of the TS packet given from the demultiplexer 5.

  For example, the channel selection control unit 8 determines that the reception is disabled when it is determined that a decoding error has been detected based on the decoding error detection information provided from the decoder 6. For example, the channel selection control unit 8 determines that the reception is not possible when it is determined that the decoding error rate is equal to or higher than a predetermined threshold based on the decoding error rate information given from the decoder 6.

  The channel selection control unit 8 determines which physical channel to select based on the channel selection request from the user and whether or not reception is possible, and controls and determines the tuner unit 3 and the demultiplexer 5. Select a physical channel. Specifically, the channel selection control unit 8 instructs the tuner unit 3 about a physical channel to be selected, and instructs the demultiplexer 5 about a broadcast service to be extracted. The channel selection control unit 8 instructs the tuner unit 3 about the physical channel to be selected, and also instructs the demultiplexer 5 about the broadcast service to be extracted, which corresponds to the channel selection control step. .

  The channel information storage unit 9 stores channel information in which a region where a digital broadcast signal can be received is associated with a physical channel through which the digital broadcast signal receivable in that region is transmitted. Storing channel information in the channel information storage unit 9 corresponds to a channel information storage step. Specifically, the channel information storage unit 9 stores a terrestrial network table that manages channel information representing physical channels of digital broadcast signals that can be received at the current position of the digital broadcast receiver 1 for all receivable channels. doing.

  The area information storage unit 10 stores adjacent area information in which an area where a digital broadcast signal can be received is associated with an area adjacent to the area (hereinafter also referred to as “adjacent area”). Storing adjacent area information in the area information storage unit 10 corresponds to an area information storage step. In this embodiment, the area information storage unit 10 is a network ID (abbreviation: nwID) determined for each region to identify the region, and the region management number and nwID area corresponding to the region ID for identifying the region. An adjacent area table which is a list of physical management channels of digital broadcasting signals that may be received in the area and area management numbers of areas determined to be adjacent areas of the nwID area is stored.

  In the adjacent area table, in addition to the nwID, the area management number of the area corresponding to the nwID, the physical channel, and the area management number of the adjacent area, a receivable broadcast such as the service name and Ts_ID of the area corresponding to the nwID Other data such as service information related to the service may be included. In the present embodiment, the adjacent area table includes an nwID, an area management number of the area corresponding to the nwID, a physical channel, a service name, Ts_ID, and an area management number of the adjacent area. A plurality of physical channels, Ts_IDs, and service names may be registered in a certain area management number in the adjacent area table. Furthermore, the same physical channel, Ts_ID, and service name may be registered in another area management number.

  When the service of the channel being viewed becomes unreceivable, the channel selection control unit 8 determines from the adjacent area table stored in the area information storage unit 10 based on the nwID of the channel that has been viewed so far. It is possible to acquire the area management number of the area that has been viewed until then and the adjacent area corresponding to the area management number. When searching for the same service as the service of the channel that has been viewed up to that point, a service having the same service name or Ts_ID is searched from services registered in the adjacent area, and the physical broadcasting the service is performed. Search from the channel.

  For example, when the digital broadcast receiving apparatus 1 is mounted on a moving body and used, the meter information acquisition unit 11 obtains information such as a speed and a moving distance when the moving body on which the digital broadcast receiving apparatus 1 is mounted moves. The information is acquired from a mobile object such as a speed meter and a distance meter of an automobile, and the acquired information is given to the channel selection control unit 8 as meter information.

  Next, a case will be described in which the digital broadcast receiving apparatus 1 cannot receive the service because it has moved to another area while receiving the specific service selected by the user, and searches for the same service. FIG. 2 shows that the mobile body equipped with the digital broadcast receiving device 1 is configured such that the first area A to the second area B, the second area B to the third area C, the third area C to the fourth area D, and the fourth area D. It is a figure which shows typically a mode that it moves to 1st area A in order from. In FIG. 2, the region boundary lines 20 of the first to fourth regions A to D are indicated by two-dot chain lines, and each region A to D of the present embodiment is a rectangle surrounded by the four region boundary lines 20. It is an area.

  In the present embodiment, the moving body moves from the first area A to the second area B, from the second area B to the third area C, from the third area C to the fourth area D, and from the fourth area D to the first area A. It is assumed that they move in order. The first area A is adjacent to the second area B and the fourth area D, and the third area C is adjacent to the fourth area D. Further, in the present embodiment, as shown in FIG. 2, between the second area B and the third area C, the radio wave condition at any point is extremely bad (hereinafter, sometimes referred to as “difficult reception area”). It is assumed that R exists. The nwID of the first area A is “0x0010”, the nwID of the second area B is “0x002C”, the nwID of the third area C is “0x00F4”, and the nwID of the fourth area D is “0x0107”. is there.

  FIG. 3 is a diagram illustrating an example of the terrestrial network table 30 in the first area A stored in the channel information storage unit 9. FIG. 4 is a diagram illustrating an example of the terrestrial network table 31 in the second region B stored in the channel information storage unit 9. When the moving body moves from the first area A shown in FIG. 2 to the second area B, the terrestrial network table to be referred to is the terrestrial network table in the first area A shown in FIG. The area network table in the second area B shown in FIG. 4 (hereinafter also referred to as “area network table for second area B”) 31 is changed from 30.

  In the first area A terrestrial network table 30, as shown in FIG. 3, as a service with Ts_ID “0xF1A0”, the physical channel (abbreviation: physical Ch) is “10”, the service name is “BBC News”, As a service with a frequency network (abbreviation: MFN) channel (abbreviation: MFN Ch) “20, 30” and a service with Ts_ID “0xF3C6”, the physical Ch is “13” and the service name is “BBC”. Service with “Weather”, MFN Ch “14, 31” and Ts_ID “0xFFA0”, Physical Ch “17”, Service Name “SBS Dorama”, MFN Ch “-(None)” As a service with Ts_ID “0xFFB0”, the physical Ch is “21”, the service name is “Quiz Frontier”, MFN Ch "38" is stored.

  In the second area B ground network table 31, as shown in FIG. 4, as the service with Ts_ID “0xE060”, the physical Ch is “12”, the service name is “CNN Sports”, and the MFN Ch is “25”. Service, Ts_ID “0xF1A0”, physical channel “31”, service name “BBC News”, MFN Ch “46”, and Ts_ID “0xF3C6”. “38”, service name “BBC Weather”, and MFN Ch “− (none)” are stored.

  From the terrestrial network tables 30 and 31 in the first area A and the second area B shown in FIG. 3 and FIG. 4, the physical channels broadcast in the first area A and the second area B are different, but “BBC News” S1 and It can be seen that “BBC Weather” S2 is broadcast with the same service name and the same Ts_ID.

  While the moving body is moving in the first area A, for example, the digital broadcast receiving apparatus 1 refers to the first area A terrestrial network table 30 shown in FIG. Service channel information. Not only the first area A terrestrial network table 30 but also the terrestrial network table of each area may be held in the channel information storage unit 9 after the channel scan once. However, when the area where the digital broadcast receiving apparatus 1 is located moves due to the movement of the mobile body and it is no longer necessary to refer to the terrestrial network table of the area before the movement, it may be deleted. When configured to delete the terrestrial network table before movement, the digital broadcast receiving apparatus 1 scans all channels every time the area moves, acquires channel information of each channel, and Create a new ground network table.

  FIG. 5 is a graph showing the relationship between the reception status and the elapsed time in each area of the same service in the first embodiment of the present invention. The example shown in FIG. 5 shows the relationship between the reception status of the service “BBC News” and the elapsed time. In FIG. 5, the horizontal axis represents the elapsed time [s] from the start of movement, and the vertical axis represents the region of the current position of the digital broadcast receiving apparatus 1 at each elapsed time. In FIG. 5, the viewable time of the service, that is, the receivable time is shown in black, and the time during which the search for the same service is executed is shown in white.

  First, it is assumed that the digital broadcast receiving apparatus 1 mounted on the mobile body receives the service “BBC News” in the first area A (nwID = 0x0010). While the service “BBC News” is being received, the mobile unit equipped with the digital broadcast receiving device 1 moves from the first area A to the second area B (nwID = 0x002C), and the time when the service cannot be received is denoted by t1. To do. When the reception is disabled, the digital broadcast receiving apparatus 1 executes a search for the same service in the second area B. The time when the service “BBC News” can be received in the second area B by the search and becomes viewable by the user is t2.

  Furthermore, a time when the mobile body moves from the second area B to the difficult reception area R while receiving the service “BBC News” and the service becomes unreceivable is set as t3. In the difficult reception area R, the search is continued because the same service cannot be received even if the search for the same service is executed. After that, the mobile body moves from the difficult reception area R to the third area C (nwID = 0x00F4), performs a search for the same service in the third area C, can receive the service “BBC News”, and is viewed by the user. The time when it becomes possible is assumed to be t4.

  Subsequently, a time when the mobile object moves from the third area C to the fourth area D (nwID = 0x0107) and the service cannot be received is t5. The search for the same service is executed in the fourth area D, and the time when the service “BBC News” can be received and the user can view is t6. Subsequently, when the mobile object moves from the fourth area D to the original first area A and the service becomes unreceivable, the same service is searched in the first area A, and the service “BBC News” Is t8, and the time when the user becomes able to view is t8.

  FIG. 6 is a diagram showing the adjacent area table 32 stored in the area information storage unit 10 according to the first embodiment of the present invention. As shown in FIG. 5, the digital broadcast receiving apparatus 1 moves to another area while receiving a specific service, and searches for the same service when the service cannot be received. If the service can be received as a result of the search, the adjacent area table 32 stored in the area information storage unit 10 of the digital broadcast receiving apparatus 1 is updated.

  In the present embodiment, as shown in FIG. 6, the adjacent region table 32 includes a region management number such as “A” and “B” representing a region, an nwID corresponding to the region represented by the region management number, The area is stored in association with the adjacent area represented by the area management number. The adjacent area is stored using area management numbers such as “A” and “B”. In the present embodiment, information such as service name, Ts_ID and physical channel is stored in the adjacent area table 32 as information for each area management number from the terrestrial network table stored in the channel information storage unit 9. Has been.

  As described above, the digital broadcast receiving device 1 performs a search for the same service in the destination area when the service becomes unreceivable due to movement in the area while receiving a certain service and the user becomes unable to view the service. To do. In the present embodiment, the digital broadcast receiving apparatus 1 obtains the time from the time when the service cannot be received to the time when the service can be received, and the obtained time is a predetermined threshold (hereinafter referred to as “threshold time”). If it is equal to or less than ΔT, the destination area is registered as an adjacent area of the source area, and if the calculated time exceeds the threshold time ΔT, the destination area is adjacent to the source area. Do not register as a region. The threshold time ΔT is appropriately defined in the software of the back end unit 7 and is determined by the specification. Specifically, the threshold time ΔT is determined according to specifications based on an actual running test and a broadcast area map.

  The threshold time ΔT is interposed between the second area B and the third area C, for example, so that the second area B and the third area C shown in FIG. 2 are not determined to be adjacent to each other. The time is set to be shorter than the time for moving in the difficult reception area R. In this case, since (t2−t1) ≦ ΔT, (t4−t3)> ΔT, (t6−t5) ≦ ΔT, and (t8−t7) ≦ ΔT in the graph shown in FIG. A and the second region B, the third region C and the fourth region D, and the fourth region D and the first region A are determined to be adjacent to each other, but the second region B and the third region C Are not adjacent to each other. Therefore, as shown in FIG. 6, in the adjacent area table 32, the second area B and the fourth area D are registered in the adjacent area of the first area A, and the first area is registered in the adjacent area of the fourth area D. A and the third area C are registered, but only the first area A is registered in the adjacent area of the second area B, and only the fourth area D is registered in the adjacent area of the third area C. .

  7 and 8 are flowcharts showing a processing procedure of the channel selection control unit 8 regarding the search operation of the same service of the digital broadcast receiving apparatus 1 according to the first embodiment of the present invention. In the present embodiment, a digital broadcast receiver 1 mounted on a mobile body receives a digital broadcast signal via an antenna 2, and decodes the decoded video signal and audio signal via an AV input / output interface 12. It is assumed that data is being output to the output device 15. In other words, it is assumed that the user of the digital broadcast receiving apparatus 1 is viewing the specific service decrypted by the digital broadcast receiving apparatus 1, for example, the service “BBC News” by the video / audio output apparatus 15. .

  When the mobile unit equipped with the digital broadcast receiving device 1 moves in each area, the service cannot be received and the user cannot view the channel. The operation according to the flowcharts shown in FIGS. 7 and 8 is performed. The processing of the flowcharts shown in FIGS. 7 and 8 is started when the digital broadcast receiving apparatus 1 is turned on, that is, turned on by the user, and power is supplied to the digital broadcast receiving apparatus 1, and the process proceeds to step a1.

  In step a1, the channel selection control unit 8 determines whether or not the service selected by the user is unreceivable. If it is determined that the service is unreceivable, the channel selection control unit 8 proceeds to step a2 and is not unreceivable. That is, if it is determined that reception is possible, it waits until it is determined that reception is not possible. For example, as shown in FIG. 2 described above, when moving from the first area A to the second area B, it is determined that the service being viewed by the user cannot be received, and the process proceeds to step a2.

  In step a2, the channel selection control unit 8 determines whether or not the adjacent region is registered in the adjacent region table 32 of the area information storage unit 10 with respect to the region before reception is disabled, that is, the region before movement. If it is determined that it is registered, the process proceeds to step a3. If it is determined that it is not registered, the process proceeds to step a7 in FIG.

  In step a3, the channel selection control unit 8 selects a region from the adjacent regions registered in the adjacent region column corresponding to the region before reception is disabled from the adjacent region table 32 stored in the area information storage unit 10. By selecting one and referring to the channel information described in the column corresponding to the selected adjacent area, the same service as the service selected by the user in this adjacent area (hereinafter sometimes referred to as “the same service”). The physical channel registered in the physical channel column is obtained as the physical channel that broadcasts), the obtained physical channel is searched, and the process proceeds to step a4.

  In the present embodiment, the channel selection control unit 8 matches the service name registered in the service name column corresponding to the selected adjacent area with the service name of the received service, or selects the selected adjacent area. If the Ts_ID registered in the corresponding Ts_ID column matches the Ts_ID of the received service, it is determined that the services are the same. Then, the channel selection control unit 8 obtains a physical channel registered in the physical channel column as a physical channel broadcasting the service determined to be the same service, and searches for the obtained physical channel.

  For example, when moving from the first area A to the second area B, the channel selection control unit 8 is registered from the adjacent area table 32 in the adjacent area column corresponding to the first area that is the area before reception is disabled. The adjacent areas, that is, the second area B and the fourth area D are obtained. The channel selection control unit 8 selects one area, for example, the second area B from these adjacent areas B and D, and determines that the services are the same from the service name or Ts_ID described in the second area B column. The physical channel in which the same service is registered is searched.

  In step a4, the channel selection control unit 8 determines whether or not the same service can be received. If it is determined that the same service can be received, the channel selection control unit 8 proceeds to step a5 and cannot receive the same service. That is, if it is determined that reception is impossible, the process proceeds to step a6.

  In step a5, the channel selection control unit 8 controls the tuner unit 3 to select a channel of the same service found. After the process of step a5 is complete | finished, it returns to step a1 and repeats the above-mentioned process.

  In step a6, the channel selection control unit 8 determines whether or not the search has been completed in all adjacent areas registered with respect to the area before reception is impossible, and the search has been completed in all adjacent areas. If it is determined that the search has been completed, the process proceeds to step a7 in FIG. 8, and if it is determined that the search has not been completed, the process returns to step a3 to start from the adjacent area registered in the adjacent area column of the adjacent area table 32. A region different from the selected region is selected, and the above-described processing is repeated. For example, when moving from the first area A to the second area B, if the second area B is selected in the previous step a3, the channel selection control unit 8 selects the fourth area D in step a3. The service having the same service name or Ts_ID described in the fourth region D column is determined as the same service, and the physical channel registered in the physical channel column corresponding to the service name column or the Ts_ID column is searched. To do.

  Subsequently, in step a7 of FIG. 8, the channel selection control unit 8 determines whether or not the terrestrial network table in the area of the current position of the digital broadcast receiving device 1 is stored in the channel information storage unit 9, and is stored. If it is determined that the data is stored, the process proceeds to step a10. If it is determined that the data is not stored, the process proceeds to step a8.

  In step a8, the channel selection control unit 8 performs a channel scan, creates a terrestrial network table in the current position area, and then proceeds to step a9. In step a9, the channel selection control unit 8 stores the created terrestrial network table in the channel information storage unit 9, and proceeds to step a10.

  In step a10, the channel selection control unit 8 acquires the terrestrial network table in the current position area stored in the channel information storage unit 9, and proceeds to step a11.

  In step a11, the channel selection control unit 8 searches for the same service from the terrestrial network table acquired in step a10. Specifically, the channel selection control unit 8 is the same as the specific service that can be received up to the physical channel registered in the terrestrial network table acquired in step a10, for example, the service “BBC News”. Search for services. In the present embodiment, the search is performed based on whether or not the service name or Ts_ID registered in the regional network table matches the service that has been receivable.

  In step a12, the channel selection control unit 8 determines whether or not the same service can be received. If it is determined that the same service can be received, the channel selection control unit 8 proceeds to step a13 and cannot receive the same service. That is, if it is determined that reception is impossible, the process proceeds to step a16. The channel selection control unit 8 determines whether or not the service name or Ts_ID registered in the regional network table acquired in step a10 matches the service that could be received up to now. Is not received, it is determined that the same service cannot be received, that is, cannot be received.

  In this way, the channel selection control unit 8 searches for the same service with reference to the regional network table in the region of the current position. For example, if it is determined that reception is not possible in step a1 after moving from the first area A to the second area B, the channel selection control unit 8 stores the second area B terrestrial network stored in the channel information storage unit 9 Refer to table 31. If the second area B terrestrial network table 31 is not stored in the channel information storage unit 9, the channel selection control unit 8 performs channel scanning in step a8 to obtain the second area B terrestrial network table 31. Need to create.

  In step a13, the channel selection control unit 8 determines whether or not the area at the current position is registered in the adjacent area table 32 as an adjacent area of the area before reception is disabled, and is registered as an adjacent area. If it is determined that the area is not registered as an adjacent area, the process proceeds to step a14.

  In step a14, the channel selection control unit 8 determines whether or not the elapsed time from the time when the received service becomes unreceivable until the time when the service can be received is equal to or less than a threshold time ΔT that is a predetermined threshold. Judging. For example, when the moving body moves from the first area A to the second area B, the channel selection control unit 8 starts the same service from the time t1 when the specific service received in the first area A becomes unreceivable. The elapsed time (t2-t1) until time t2 at which reception of the same service is enabled in the second area B by the search of (2) is obtained, and whether this elapsed time (t2-t1) is equal to or less than the threshold time ΔT. Judging. When the channel selection control unit 8 determines that the elapsed time is equal to or less than the threshold time ΔT, the channel selection control unit 8 proceeds to step a15. When the channel selection control unit 8 determines that the elapsed time exceeds the threshold time ΔT, the channel selection control unit 8 proceeds to step a5 in FIG. The above-described processing is performed.

  In step a15, the channel selection control unit 8 sets the area before the reception of the adjacent area table 32 in the area information storage unit 10 and the area where the same service can be received as the adjacent areas. Register in table 32. Specifically, the channel selection control unit 8 receives the area that can be received in the adjacent area column corresponding to the column of the first area A, for example, the second area, for example, the second area before the reception of the adjacent area table 32 becomes impossible. Region B is registered, and then the first region A is registered in the adjacent region column corresponding to the second region B column.

  After the process of step a15 is completed, the process proceeds to step a5 in FIG. 7, and reception of the same service is continued. If it is determined in step a14 that the elapsed time exceeds the threshold time ΔT, the channel selection control unit 8 proceeds to step a5 in FIG. 7 without passing through step a15, that is, adjacent to the adjacent area table 32. Without registering the region, the process proceeds to step a5 and continues to receive the same service.

  In step a16, the channel selection control unit 8 determines whether or not the search for all channels registered in the terrestrial network table acquired in step a10 has been completed. If the channel selection control unit 8 determines that all channels have been searched, the channel selection control unit 8 returns to step a1 in FIG. 7 and repeats the above-described processing without selecting a new channel. If the channel selection control unit 8 determines that the search of all channels has not been completed, the channel selection control unit 8 returns to step a11 and repeats the above-described processing for other channels, that is, performs a search for the same service again.

  As described above, according to the present embodiment, a physical channel is selected by the tuner unit 3 based on an instruction from the channel selection control unit 8, and a digital broadcast signal transmitted through the physical channel is acquired. A signal of a target broadcast service is extracted from the digital broadcast signal by the demultiplexer 5 and output by the AV input / output interface 12. The area information storage unit 10 stores an adjacent area table 32 as adjacent area information, and the channel information storage unit 9 stores a terrestrial network table as channel information of each area.

  As shown in FIG. 2, when a mobile body equipped with the digital broadcast receiving device 1 moves between regions and the broadcast service changes from the receivable state to the unreceivable state, according to the flowcharts shown in FIGS. 7 and 8. The channel selection control unit 8 searches for the same broadcast service as the received broadcast service.

  If the area at the current position is not registered as an adjacent area in the adjacent area table 32, the same service as that service is found by the search from the point when the received service is disabled in step a14 in FIG. The elapsed time until the point at which reception is possible is obtained. If it is determined that the elapsed time is equal to or less than the threshold time ΔT, in step a15, the area located in the reception enabled state and the area where the same service can be received by the search are adjacent to each other. Is registered in the adjacent area table 32 as an adjacent area.

  As a result, at the next search, the channel selection control unit 8 gives priority to a physical channel that may be received based on the channel information of the adjacent area registered in the adjacent area table 32 in step a3 of FIG. Can be searched. Specifically, the channel selection control unit 8 refers to the service name column or Ts_ID column corresponding to the region registered in the adjacent region column of the adjacent region table 32, and the service name or Ts_ID registered in the service name column. The Ts_ID registered in the column may be determined to be the same service, and the physical channel registered in the physical channel column corresponding to the service name column or the Ts_ID column may be searched.

  Therefore, for example, when searching all channels registered in the terrestrial network table in ascending or descending order based on the terrestrial network table in the current location, as in steps a7, a10 to a11 of FIG. 8, and FIG. As in steps a7 to a11, when the terrestrial network table of the current location is not stored, the search can be performed at a higher speed than when all channels are searched in ascending or descending order. As a result, a receivable broadcast service channel can be set in as short a time as possible.

  In the present embodiment, if it is determined in steps a2 to a4 in FIG. 7 that the same service is receivable as a result of the search based on the adjacent area table 32, the elapsed time from unreceivable to receivable Even if the elapsed time exceeds the threshold time ΔT without determining whether the time is equal to or less than the threshold time ΔT, the process proceeds to step a5 without deleting the adjacent area. Also, in step a13 in FIG. 8, when it is determined that the area where the same service can be received is registered as an adjacent area, the elapsed time from the reception impossible to the reception possible in step a14 is equal to or less than the threshold time ΔT. Even if the elapsed time exceeds the threshold time ΔT without determining whether or not there is, the process proceeds to step a5 as it is without deleting the adjacent area. If it is determined in step a13 of FIG. 8 that an area where the same service can be received is registered as an adjacent area, for example, it is registered in the adjacent area table 32 as a physical channel that can be received in the adjacent area. This is a case where the same service can be received on a physical channel that is not used.

  As described above, in this embodiment, when it is determined that the same service can be received in an area registered as an adjacent area, that is, the movement when the service changes from the receivable state to the unreceivable state, In the case of movement between regions registered as regions adjacent to each other in the region table 32, the adjacent region table 32 in both cases where the elapsed time is equal to or less than the threshold time ΔT and when the elapsed time exceeds the threshold time ΔT. Maintain registrations of regions registered as regions adjacent to each other.

  In other words, in the present embodiment, the neighboring area once registered is not deleted even if the elapsed time exceeds the threshold time ΔT, for example, regardless of the elapsed time from reception impossible to reception possible, and the elapsed time is the threshold time. Even if it is ΔT or less, the adjacent area is not updated and the registration is maintained.

  For example, in the adjacent area table 32, when the number of adjacent areas registered in the adjacent area field corresponding to a certain area management number field has increased considerably, it takes time to find an adjacent area that can receive the same service. Sometimes. In this case, even if the same service becomes receivable as a result of searching for the same service based on the adjacent area table 32 as described above, the process from reception impossible to reception possible depending on the value of the threshold time ΔT. The time may exceed the threshold time ΔT.

  If the registered adjacent area is deleted when the elapsed time exceeds the threshold time ΔT, the next time a search is performed based on the adjacent area table 32, there is a possibility of reception in the area registered as the adjacent area. A certain physical channel cannot be preferentially searched, and it takes a long time to find a physical channel that can receive the same service.

  In order to prevent the time until a physical channel that can receive the same service from becoming long in this way, in this embodiment, as described above, an area once registered as an adjacent area is passed. Even if the time exceeds the threshold time ΔT, it is not deleted from the adjacent area column when the adjacent area table 32 is updated. As a result, it is possible to preferentially search for a physical channel that can be received, so that it is possible to prevent an increase in time until a physical channel that can receive the same service is found.

  In addition, for an area that has already been registered as an adjacent area, performing the registration process as an adjacent area when the elapsed time is equal to or less than the threshold time ΔT, and updating the adjacent area is an unnecessary process, which complicates the process. It only invites. Therefore, in the present embodiment, for an area that has already been registered as an adjacent area, even if the elapsed time is equal to or less than the threshold time ΔT, the adjacent area is not updated and the process proceeds to step a5 and the same service is performed. Is receiving. Thereby, complication of processing can be prevented.

  Further, in the present embodiment, as shown in FIG. 6, the adjacent area table 32 includes service information related to a broadcast service that can be received in an area corresponding to nwID, for example, a service name, Ts_ID, and a physical channel. When the channel selection control unit 8 searches for the same service based on the adjacent area table 32, the service name field or the Ts_ID field corresponding to the area registered in the adjacent area field of the adjacent area table 32 is referred to. The service name registered in the service name or the service with the same Ts_ID registered in the Ts_ID field is determined to be the same service, and the physical channel registered in the physical channel field corresponding to the service name field or the Ts_ID field is searched. do it. As a result, the channel selection control unit 8 can preferentially search for physical channels that can receive the same service, so that the time required to find a physical channel that can receive the same service can be reduced. it can.

<Second Embodiment>
Next, a digital broadcast receiving apparatus according to the second embodiment of the present invention will be described. The digital broadcast receiving apparatus according to the present embodiment has the same configuration as that of the digital broadcast receiving apparatus 1 according to the first embodiment described above, and therefore the illustration and description common to the first embodiment will be omitted. Also in the present embodiment, as in the above-described first embodiment, as shown in FIG. 2 described above, the mobile body on which the digital broadcast receiving device 1 is mounted is changed from the first area A to the second area B, From the second area B to the third area C, from the third area C to the fourth area D, from the fourth area D to the first area A in order, between the second area B and the third area C, It is assumed that there is a difficult reception area R in which the radio wave condition in any area is extremely bad. The configuration of the terrestrial network tables such as the first area A and the second area B is the same as that of the first embodiment described above.

  In the present embodiment, the power of the digital broadcast receiving apparatus 1 is turned off in the third area C, and the power of the digital broadcast receiving apparatus 1 is turned on again in the fourth area D. Different from the first embodiment.

  FIG. 9 is a graph showing the relationship between the reception situation in each area of the same service and the moving distance of the digital broadcast receiving apparatus 1 in the second embodiment of the present invention. In FIG. 9, the horizontal axis represents the moving distance [m] of the digital broadcast receiving apparatus 1, and the vertical axis represents the area of the current position of the digital broadcast receiving apparatus 1 at each moving distance. In FIG. 9, a service viewable section, that is, a receivable section is shown in black, and a section in which a search for the same service is executed is shown in white.

  First, it is assumed that the digital broadcast receiving apparatus 1 mounted on the mobile body receives the service “BBC News” in the first area A (nwID = 0x0010). While receiving the service “BBC News”, the mobile unit equipped with the digital broadcast receiving device 1 moves from the first area A to the second area B (nwID = 0x002C), and the digital when the service becomes unreceivable. The moving distance of the broadcast receiving apparatus 1 (hereinafter sometimes simply referred to as “moving distance”) is L1. If reception is disabled, the digital broadcast receiving apparatus 1 executes a search for the same service in the second area B. The moving distance when the service “BBC News” can be received in the second area B by the search is L2. The movement distance is acquired based on a value given from the meter information acquisition unit 11. For example, the meter information acquisition unit 11 constantly monitors a distance meter of a vehicle, moves from one region to another region, acquires the travel distance of the vehicle detected when the service is not received, The acquired value is given to the tuning control unit 8. The channel selection control unit 8 obtains the moving distance of the moving body based on the value given from the meter information acquisition unit 11.

  Furthermore, the moving distance at the time when the moving object moves from the second area B to the difficult receiving area R while receiving the service “BBC News” and the service becomes unreceivable is L3. In the difficult reception area R, the search is continued because the same service cannot be received even if the search for the same service is executed. After that, the mobile body moves from the difficult reception area R to the third area C (nwID = 0x00F4), performs a search for the same service in the third area C, and when the service “BBC News” can be received. The moving distance is L4.

  Subsequently, the moving distance at the time when the user turns off the power of the digital broadcast receiving apparatus 1 in the third area C is set to L5. Thereafter, the moving body moves from the third area C to the fourth area D (nwID = 0x0107), and the moving distance when the digital broadcast receiving device 1 is turned on by the user in the fourth area D is expressed as L6. And Thereafter, a search for the same service is executed in the fourth area D, and the moving distance at the time when the service “BBC News” becomes receivable is set to L7.

  Subsequently, the moving object moves from the fourth area D to the original first area A, and the moving distance when the service becomes unreceivable is set to L8. The moving distance when “BBC News” can be received is L9.

  FIG. 10 is a diagram showing the adjacent area table 33 stored in the area information storage unit 10 according to the second embodiment of the present invention. As shown in FIG. 9, the digital broadcast receiving apparatus 1 moves to another area while receiving a specific service, and searches for the same service when the service cannot be received. If the service can be received as a result of the search, the adjacent area table 33 stored in the area information storage unit 10 of the digital broadcast receiving apparatus 1 is updated.

  As shown in FIG. 10, the adjacent area table 33 is similar to the first embodiment described above, and the areas represented by area management numbers such as “A” and “B” representing the areas and the area management numbers. And the adjacent area of the area represented by the area management number are stored in association with each other. The adjacent area is stored using area management numbers such as “A” and “B”. Also in the present embodiment, as in the first embodiment described above, information such as the service name, Ts_ID, and physical channel is obtained for each regional management number from the ground network table stored in the channel information storage unit 9. The information is stored in the adjacent area table 33 as information.

  As described above, if a service cannot be received due to movement of a region while receiving a certain service, the digital broadcast receiving apparatus 1 executes a search for the same service in the destination region. In the present embodiment, the digital broadcast receiving apparatus 1 obtains a moving distance from the time when the service becomes unreceivable to the time when the service becomes receivable, and the obtained moving distance is a predetermined threshold (hereinafter “threshold”). If it is equal to or less than ΔL, the destination area is registered as an adjacent area of the source area, and if the calculated movement distance exceeds the threshold distance ΔL, the destination area is set as the source area. Do not register as an adjacent area of. The threshold distance ΔL is appropriately defined in the software of the back end unit 7 and is determined by the specification. Specifically, the threshold distance ΔL is determined according to specifications based on an actual running test and a broadcast area map.

  For example, the threshold distance ΔL is interposed between the second area B and the third area C so that the second area B and the third area C shown in FIG. 2 are not determined to be adjacent to each other. The distance is set to be shorter than the distance traveled in the difficult reception area R. In this case, in the graph shown in FIG. 9, (L2−L1) ≦ ΔL, (L4−L3)> ΔL, and (L9−L8) ≦ ΔL, the first area A and the second area B, and The fourth area D and the first area A are determined to be adjacent to each other, but the second area B and the third area C are determined to be not adjacent to each other.

  The travel distance L5 corresponds to the travel distance when the service becomes unreceivable, and the travel distance L7 corresponds to the travel distance when the service becomes receivable, but the travel distance L5 is digital. The moving distance at the time when the power of the broadcast receiving apparatus 1 is turned off. The moving distance L7 executes a search for the same service after the digital broadcast receiving apparatus 1 is turned on at the moving distance L6. This is the distance traveled when the service “BBC News” can be received. Therefore, the digital broadcast receiving apparatus 1 does not obtain the difference in movement distance between the movement distance L5 and the movement distance L7, and does not recognize the third area C and the fourth area D as adjacent areas. That is, the digital broadcast receiving apparatus 1 is configured such that the areas before and after turning on and off the power are not recognized as adjacent areas without obtaining the difference in travel distance that accompanies turning on and off.

  Therefore, in the adjacent area table 33 of the present embodiment, as shown in FIG. 10, the adjacent area of the first area A is similar to the adjacent area table 32 in the first embodiment shown in FIG. The second area B and the fourth area D are registered, and the first area A is registered in the adjacent area of the second area B, but the fourth area D is registered in the adjacent area of the third area C. In addition, in the adjacent area of the fourth area D, only the first area A is registered, and the third area C is not registered.

  FIG. 11 and FIG. 12 are flowcharts showing the processing procedure of the channel selection control unit 8 regarding the search operation for the same service of the digital broadcast receiving apparatus 1 in the second embodiment of the present invention. Also in the present embodiment, as in the first embodiment, the digital broadcast receiver 1 mounted on the mobile body receives the digital broadcast signal via the antenna 2 and decodes the decoded video signal and audio. It is assumed that the signal is output to the video / audio output device 15 via the AV input / output interface 12.

  In the present embodiment, when a mobile body equipped with the digital broadcast receiving device 1 moves in each region, when the service becomes unreceivable and the user becomes unable to view, the same service is searched. The channel selection control unit 8 operates according to the flowcharts shown in FIGS. 11 and 12. The processing of the flowcharts shown in FIGS. 11 and 12 is started when the digital broadcast receiving apparatus 1 is turned on, that is, turned on by the user, and power is supplied to the digital broadcast receiving apparatus 1, and the process proceeds to step b1.

  Since each process of step b1-step b6 of the flowchart shown in FIG. 11 is the same as each process of step a1-step a6 of the flowchart shown in FIG. 7, description is abbreviate | omitted. In the present embodiment, when the channel selection control unit 8 determines in step b2 that no adjacent area is registered in the adjacent area table 33 of the area information storage unit 10, the process proceeds to step b7 in FIG.

  In step b5, after the channel selection control unit 8 selects a channel of the same service found, the channel selection control unit 8 returns to step b1 and repeats the processing from step b1. Further, when the channel selection control unit 8 determines in step b6 that the search has been completed in all adjacent areas registered for the area before reception is disabled, the process proceeds to step b7 in FIG. If it is determined that the search has not ended, the process returns to step b3 and the search is repeated.

  Each process of step b7 to step b13, step b16, and step b17 in the flowchart shown in FIG. 12 is the same as step a7 to step a13, step a15, and step a16 in the flowchart shown in FIG. In this embodiment, in step b13, if the channel selection control unit 8 determines that the area at the current position is registered as an adjacent area, the channel selection control unit 8 proceeds to step b5 in FIG. 11 and registers the area at the current position as an adjacent area. If it is determined that it is not, the process proceeds to step b14.

  In step b14, the channel selection control unit 8 determines whether or not the moving distance from the time when the received service becomes unreceivable to the time when the service can be received is equal to or less than a threshold distance ΔL that is a predetermined threshold. Judging. For example, when the moving body moves from the first area A to the second area B, the channel selection control unit 8 starts to receive the same service from the time when the specific service received in the first area A becomes unreceivable. A travel distance difference (L2−L1) until the same service can be received in the second area B by the search is determined, and it is determined whether or not the travel distance difference is equal to or less than a threshold distance ΔL. If the channel selection control unit 8 determines that the distance is equal to or less than the threshold distance ΔL, the channel selection control unit 8 proceeds to step b15. If the channel selection control unit 8 determines that the threshold distance ΔL is exceeded, the adjacent region is registered in the adjacent region table 33. Without proceeding to step b5 in FIG. 11, the service reception is continued.

  In step b15, the channel selection control unit 8 determines whether or not the search performed in step b11 is a search from the reception disabled state when the power is turned on, that is, the reception disabled state is turned on. Determine if it happened sometimes.

  When the channel selection control unit 8 determines in step b15 that the search is not from the reception disabled state when the power is turned on, that is, the reception disabled state is not caused when the power is turned on, the process proceeds to step b16. In the adjacent area table 33 in the area information storage unit 10, the area before the reception is disabled and the area where the same service can be received are registered as adjacent areas. For example, when the moving body moves from the first area A to the second area B, the channel selection control unit 8 receives the reception in the adjacent area column of the first area A, which is the area before the reception of the adjacent area table 33 becomes impossible. The second area B, which is an area that has become possible, is registered, and then the first area A is registered in the adjacent area column of the second area B. After the process of step b16 is complete | finished, it transfers to step b5 of FIG. 11, and continues reception of the same service.

  When the channel selection control unit 8 determines in step b14 that the movement distance exceeds the threshold distance ΔL, the channel selection control unit 8 proceeds to step b5 in FIG. 11 without passing through step b15 and step b16, that is, the adjacent area table 33. Without registering the adjacent area, the process proceeds to step b5 and continues to receive the same service. On the other hand, if the channel selection control unit 8 determines in step b15 that the search is from the reception disabled state when the power is turned on, the channel selection control unit 8 proceeds to step b5 in FIG. 11 without receiving step b16 and receives the same service. to continue.

  If the channel selection control unit 8 determines in step b17 that the search for all channels registered in the terrestrial network table acquired in step b10 has been completed, the process returns to step b1 in FIG. If it is determined that the search for the other channel has not been completed, the process returns to step b11 and the search for the same service is repeated for the other channels.

  As described above, according to the present embodiment, similarly to the first embodiment described above, a physical channel is selected by the tuner unit 3 based on an instruction from the tuning control unit 8, and the physical channel is selected. The digital broadcast signal transmitted in the above is acquired, and the signal of the target broadcast service is extracted from the digital broadcast signal by the demultiplexer 5 and output by the AV input / output interface 12. The area information storage unit 10 stores an adjacent area table 33 as adjacent area information, and the channel information storage unit 9 stores a terrestrial network table as channel information of each area.

  In the present embodiment, as shown in FIG. 2, when a mobile body equipped with the digital broadcast receiving apparatus 1 moves between regions, the broadcast service changes from the receivable state to the unreceivable state, as shown in FIGS. In accordance with the flowchart shown in FIG. 12, the channel selection control unit 8 searches for the same broadcast service as the received broadcast service.

  If the area at the current position is not registered as an adjacent area in the adjacent area table 33, the same service as that service is searched by the search from the time when the received service is disabled in step b14 in FIG. The moving distance up to the time when reception is possible is obtained. If it is determined that the moving distance is equal to or less than the threshold distance ΔL, the area located in the reception enabled state and the area where the same service can be received by the search in step b16 after step b15 Are registered in the adjacent area table 33 as adjacent areas adjacent to each other.

  As a result, at the next search, the channel selection control unit 8 gives priority to the physical channels that may be received based on the channel information of the adjacent area registered in the adjacent area table 33 in step b3 of FIG. Can be searched.

  Accordingly, for example, when searching all channels registered in the terrestrial network table in ascending order or descending order based on the terrestrial network table in the current position, as in steps b7, b10 to b11 in FIG. 12, and FIG. As in steps b7 to b11, when the terrestrial network table in the current position is not stored, the search can be performed at a higher speed than when all channels are searched in ascending or descending order. As a result, a receivable broadcast service channel can be set in as short a time as possible.

  Further, in this embodiment, even if it is determined in step b14 in FIG. 12 that the moving distance from the unreceivable to the receivable is equal to or less than the threshold distance ΔL, in step b15, the search from the unreceivable state when the power is turned on is performed. If it is not judged that it is not, it does not transfer to step b16. That is, in the present embodiment, it is determined in step b14 that the moving distance from the reception disabled state to the reception enabled state is equal to or less than the threshold distance ΔL, and in step b15 it is determined that the search is not from the reception disabled state when the power is turned on. Then, in step b16, the area located in the receivable state and the area where the same service can be received by the search are registered in the adjacent area table 33 as adjacent areas adjacent to each other. .

  This prevents areas that are not adjacent areas from being erroneously determined to be adjacent areas when the power is turned on / off, and prevents erroneous adjacent areas from being registered in the adjacent area table 33. . Therefore, when the channel selection control unit 8 performs a search based on the adjacent area registered in the adjacent area table 33, it is possible to prevent a physical channel that cannot be received from being erroneously searched, thereby reducing the time required for the search. can do.

  In the first embodiment described above, power on / off was not considered, but in the first embodiment as well, power on / off is considered as in the present embodiment. Is preferred. Specifically, between the steps a14 and a15 in FIG. 8 described above, whether the search performed in step a11 is the same step as step b15 in FIG. It is preferable to provide a step of determining whether or not. If it is determined in this step that the search is not from the reception disabled state when the power is turned on, the process proceeds to step a15. If it is determined that the search is from the reception disabled state when the power is turned on, the process proceeds to step a15. Without moving to step a5.

  Thus, as in the present embodiment, areas that are not adjacent areas are prevented from being erroneously determined to be adjacent areas when the power is turned on / off, and erroneous adjacent areas are registered in the adjacent area table 32. Can be prevented. Therefore, when the channel selection control unit 8 performs a search based on the adjacent area registered in the adjacent area table 32, it is possible to prevent a physical channel that cannot be received from being erroneously searched, thereby reducing the time required for the search. can do.

  In this embodiment, as in the first embodiment described above, when it is determined in steps b2 to b4 in FIG. 11 that the same service can be received as a result of the search based on the adjacent area table 33. Does not determine whether or not the travel distance from the unreceivable to the receivable is equal to or less than the threshold distance ΔL, and even if the travel distance exceeds the threshold distance ΔL, the adjacent area is not deleted and step b5 is performed as it is. Migrate to Also, in step b13 in FIG. 12, when it is determined that the area where the same service can be received is registered as an adjacent area, it is determined whether the moving distance in step b14 is equal to or less than the threshold distance ΔL. Even if the moving distance exceeds the threshold distance ΔL, the process proceeds to step b5 without deleting the adjacent area.

  As described above, in this embodiment, when it is determined that the same service can be received in an area registered as an adjacent area, that is, the movement when the service changes from the receivable state to the unreceivable state, In the case of movement between areas registered as areas adjacent to each other in the area table 33, the adjacent area table 33 in both cases where the movement distance is equal to or less than the threshold distance ΔL and where the movement distance exceeds the threshold distance ΔL. Maintain registrations of regions registered as regions adjacent to each other.

  In other words, in the present embodiment, the registered neighboring area is not deleted even if the moving distance exceeds the threshold distance ΔL, for example, regardless of the moving distance from the unreceivable to the receivable, and the moving distance is the threshold distance. Even if it is ΔL or less, the adjacent area is not updated and the registration is maintained.

  For example, in the adjacent area table 33, when the number of adjacent areas registered in the adjacent area field corresponding to a certain area management number field has increased considerably, it takes time to find an adjacent area that can receive the same service. Sometimes. In this case, even if the same service becomes receivable as a result of searching for the same service based on the adjacent area table 33 as described above, the movement from the unreceivable to the receivable depending on the value of the threshold distance ΔL. The distance may exceed the threshold distance ΔL.

  If the registered adjacent area is deleted when the moving distance exceeds the threshold distance ΔL, the next possibility of receiving in the area registered as the adjacent area when performing a search based on the adjacent area table 33 A certain physical channel cannot be preferentially searched, and it takes a long time to find a physical channel that can receive the same service.

  In this embodiment, in order to prevent the time until a physical channel that can receive the same service from becoming long as described above, in this embodiment, as described above, a region once registered as an adjacent region is moved. Even if the distance exceeds the threshold distance ΔL, it is not deleted from the adjacent area column when the adjacent area table 33 is updated. As a result, it is possible to preferentially search for a physical channel that can be received, so that it is possible to prevent an increase in time until a physical channel that can receive the same service is found.

  In addition, for an area that has already been registered as an adjacent area, performing the registration process as an adjacent area when the moving distance is equal to or less than the threshold distance ΔL, and updating the adjacent area is an unnecessary process, which complicates the process. It only invites. Therefore, in the present embodiment, for an area that has already been registered as an adjacent area, even if the movement distance is equal to or less than the threshold distance ΔL, the adjacent area is not updated and the process proceeds to step b5 as it is, Is receiving. Thereby, complication of processing can be prevented.

  In the present embodiment, as shown in FIG. 10, the adjacent area table 33 is similar to the first embodiment described above in that service information relating to broadcast services that can be received in the area corresponding to the nwID, for example, service names , Ts_ID and physical channel. When the channel selection control unit 8 searches for the same service based on the adjacent area table 33, the service name field or the Ts_ID field corresponding to the area registered in the adjacent area column of the adjacent area table 33 is referred to. A service whose service name or Ts_ID registered in the Ts_ID column matches is determined to be the same service, and a physical channel registered in the physical channel column corresponding to the service name column or Ts_ID column is searched. do it. As a result, the channel selection control unit 8 can preferentially search for physical channels that can receive the same service, so that the time required to find a physical channel that can receive the same service can be reduced. it can.

  Each above-mentioned embodiment is only illustration of this invention, and can change a structure within the scope of the present invention. For example, the configuration of the digital broadcast receiving apparatus 1 shown in FIG. 1 is merely an example, and may be configured to include other hardware blocks and software blocks as necessary.

  Further, the digital broadcast receiving apparatus 1 shown in FIG. 1 shows a configuration in which the video is reproduced by the video display device 15 after being decoded by the decoder 6, but this configuration is only an example, and the content of the digital broadcast wave is shown. The data format and the playback mechanism are not limited to those described above.

  In the schematic diagram of the region shown in FIG. 2, the region is a rectangular region surrounded by four region boundary lines 20, but the shape of each region defined by the region boundary line 20 is any shape such as a circle and a polygon. It may be a thing.

  In addition, a schematic diagram assuming an automobile is shown as a mobile body equipped with the digital broadcast receiving apparatus 1 shown in FIG. 2, but the present invention is preferably implemented even if the mobile body is another vehicle such as a train. can do. Furthermore, when the digital broadcast receiving apparatus 1 is incorporated in a mobile phone or the like, a user carrying the mobile phone is applied as a mobile object.

  As described above, the adjacent area tables 32 and 33 shown in FIGS. 7 and 11 hold information such as the nwID, the adjacent area, and the service name. However, the service ID and the affiliated station ID are stored as necessary. Other data may be held.

  DESCRIPTION OF SYMBOLS 1 Digital broadcast receiver, 2 Antenna, 3 Tuner part, 4 Demodulator part, 5 Demultiplexer, 6 Decoder, 7 Back end part, 8 Channel selection control part, 9 Channel information storage part, 10 Area information storage part, 11 Meter information Acquiring unit, 12 AV input / output interface, 13 Remote control light receiving unit, 15 Video display device, 16 Remote controller, 20 Regional boundary line, 30 Terrestrial network table for first area A, 31 Terrestrial network table for second area B, 32, 33 Adjacent area table.

Claims (9)

A tuner unit that selects a physical channel and acquires a digital broadcast signal transmitted on the selected physical channel;
A signal extraction unit that extracts a broadcast service signal to be extracted from the digital broadcast signal acquired by the tuner unit;
A signal output unit that outputs the signal of the broadcast service extracted by the signal extraction unit;
An area information storage unit that stores information indicating a specific area, the name of the broadcast service, information on the physical channel, and adjacent area information including information indicating an area adjacent to the specific area;
A channel information storage unit for storing a table including channel information in which the specific area is associated with a physical channel through which a digital broadcast signal receivable in the area is transmitted ;
When the broadcast service is changed from the receive state to the Ready state by the movement between the prior SL region,
In the destination area, search for the same broadcast service as the broadcast service by searching,
Obtain the elapsed time from the time when the broadcast service becomes unreceivable until the time when the same broadcast service as the broadcast service becomes receivable by the search,
The elapsed time is judged to be less than the predetermined threshold value, registered in the neighboring area information as area adjacent the transfer source region and the previous SL destination region was located at the time of the reception state And
The tuner unit is provided with a channel selection control unit that selects a physical channel included in the table of the region registered in the adjacent region information among the tables stored in the channel information storage unit. A digital broadcast receiver characterized by the above. The tuning control unit is
When the movement when the broadcast service changes from a receivable state to a non-receivable state is a movement between areas registered as adjacent areas in the adjacent area information, and the elapsed time is equal to or less than the threshold value 2. The digital broadcast reception according to claim 1, wherein, in both cases where the elapsed time exceeds the threshold value, the registration of the area registered as an adjacent area in the adjacent area information is maintained. apparatus. The tuning control unit is
If it is determined that the elapsed time is less than or equal to the threshold value, and the reception-impossible state is not caused when power is turned on, the area that was located when the reception was possible and the broadcast 3. The digital broadcast receiving apparatus according to claim 1, wherein an area where the same broadcast service as the service can be received by the search is registered in the adjacent area information as an adjacent area. A tuner unit that selects a physical channel and acquires a digital broadcast signal transmitted on the selected physical channel;
A signal extraction unit that extracts a broadcast service signal to be extracted from the digital broadcast signal acquired by the tuner unit;
A signal output unit that outputs the signal of the broadcast service extracted by the signal extraction unit;
An area information storage unit that stores information indicating a specific area, the name of the broadcast service, information on the physical channel, and adjacent area information including information indicating an area adjacent to the specific area;
A channel information storage unit for storing a table including channel information in which the specific area is associated with a physical channel through which a digital broadcast signal receivable in the area is transmitted ;
When the broadcast service is changed from the receive state to the Ready state by the movement between the prior SL region,
In the destination area, search for the same broadcast service as the broadcast service by searching,
Obtaining the moving distance from the time when the broadcast service is disabled to the time when the same broadcast service as the broadcast service can be received by the search,
The moving distance is judged to be less than the predetermined threshold value, registered in the neighboring area information as area adjacent the transfer source region and the previous SL destination region was located at the time of the reception state And
The tuner unit is provided with a channel selection control unit that selects a physical channel included in the table of the region registered in the adjacent region information among the tables stored in the channel information storage unit. A digital broadcast receiver characterized by the above. The tuning control unit is
When the movement when the broadcast service is changed from a receivable state to a non-receivable state is a movement between areas registered as adjacent areas in the adjacent area information, the moving distance is equal to or less than the threshold value. 5. The digital broadcast reception according to claim 4, wherein registration of the areas registered as areas adjacent to each other in the adjacent area information is maintained in both cases where the moving distance exceeds the threshold value. apparatus. The tuning control unit is
If it is determined that the movement distance is equal to or less than the threshold value, and it is determined that the unreceivable state does not occur when power is turned on, the area that was located when the receivable state was present, and the broadcast 6. The digital broadcast receiving apparatus according to claim 4, wherein an area where the same broadcast service as the service can be received by the search is registered in the adjacent area information as an adjacent area. The adjacent area information is
7. The digital broadcast receiving apparatus according to claim 1, further comprising service information related to a broadcast service that can be received in an area where the digital broadcast signal can be received. A tuner step for selecting a physical channel and acquiring a digital broadcast signal transmitted on the selected physical channel;
A signal extraction step of extracting a broadcast service signal to be extracted from the digital broadcast signal acquired in the tuner step;
A signal output step of outputting the broadcast service signal extracted in the signal extraction step;
An area information storage step for storing adjacent area information including information indicating a specific area, the name of the broadcast service, information on the physical channel, and information indicating an area adjacent to the specific area;
A channel information storing step for storing a table including channel information in which the specific area is associated with a physical channel through which a digital broadcast signal receivable in the area is transmitted ;
When the broadcast service is changed from the receive state to the Ready state by the movement between the prior SL region,
In the destination area, search for the same broadcast service as the broadcast service by searching,
Obtain the elapsed time from the time when the broadcast service becomes unreceivable until the time when the same broadcast service as the broadcast service becomes receivable by the search,
The elapsed time is judged to be less than the predetermined threshold value, the source region and the previous SL adjacent area information as the previous SL destination areas adjacent the areas from each other which is located at the time of the reception state Registered with
The tuner step includes a channel selection control step of selecting a physical channel included in a table of regions registered in the adjacent region information among the tables stored in the channel information storage step. Digital broadcast receiving method. A tuner step for selecting a physical channel and acquiring a digital broadcast signal transmitted on the selected physical channel;
A signal extraction step of extracting a broadcast service signal to be extracted from the digital broadcast signal acquired in the tuner step;
A signal output step of outputting the broadcast service signal extracted in the signal extraction step;
An area information storage step for storing adjacent area information including information indicating a specific area, the name of the broadcast service, information on the physical channel, and information indicating an area adjacent to the specific area;
A channel information storing step for storing a table including channel information in which the specific area is associated with a physical channel through which a digital broadcast signal receivable in the area is transmitted ;
When the broadcast service is changed from the receive state to the Ready state by the movement between the prior SL region,
In the destination area, search for the same broadcast service as the broadcast service by searching,
Obtaining the moving distance from the time when the broadcast service is disabled to the time when the same broadcast service as the broadcast service can be received by the search,
The moving distance is judged to be less than the predetermined threshold value, the source region and the previous SL adjacent area information as the previous SL destination areas adjacent the areas from each other which is located at the time of the reception state Registered with
The tuner step includes a channel selection control step of selecting a physical channel included in a table of regions registered in the adjacent region information among the tables stored in the channel information storage step. Digital broadcast receiving method.