JP6425866B2 - Mobile receiver and broadcast system switching method for mobile receiver - Google Patents

Description

  The present invention relates to a mobile receiver which can be mounted on a mobile and can switch a broadcasting system.

  So-called simultaneous broadcasting is known, in which programs of the same content are simultaneously broadcast in parallel by different broadcasting methods. For example, in ISDB-T (Integrated Services Digital Broadcasting-Terrestrial), which is a standard for Japanese terrestrial digital television broadcasting, the frequency bandwidth per channel is divided into 13 segments, 12 segments for high-vision broadcasting, mobile One segment is assigned to the receiver, and simultaneous broadcasting is performed. A 12-segment broadcast can transmit high quality video and audio, but is not well suited for mobile reception. On the other hand, one-segment broadcasting is suitable for mobile reception, although it results in transmission of low quality video and audio. For this reason, some mobile receivers have a function of automatically switching between 12-segment broadcasting and 1-segment broadcasting depending on the situation.

  For example, Patent Document 1 describes a digital broadcast receiving apparatus that switches between 12-segment broadcasting and 1-segment broadcasting according to a program category being viewed.

JP, 2014-165687, A

  However, in the digital broadcast receiving apparatus of Patent Document 1, it is determined which one of the 12-segment broadcast and 1-segment broadcast reception modes should be used based on only the program category being viewed. Therefore, depending on the program genre, there is a problem that switching to 12-segment broadcasting is performed even if the reception state is bad, and conversely, switching to one-segment broadcasting is performed even if the reception state is good.

  The present invention has been made to solve the above-described problems, and has as its object to obtain a mobile receiver capable of switching to a broadcast system according to a program genre in consideration of a reception state.

  A mobile receiver according to the present invention switches between a first broadcasting method and a second broadcasting method higher in quality than the first broadcasting method for broadcasting a program having the same content as the first broadcasting method. A mobile receiver, which uses a parameter setting unit that sets a switching parameter corresponding to a program category being viewed as a switching parameter used for processing, and the reception status information, and the reception status conforms to the broadcast format being viewed And a match determination unit that determines whether the broadcast system being viewed matches the priority broadcast scheme indicated by the switching parameter set by the parameter setting unit, and the determination by the match determination unit If the result is nonconforming and the judgment result by the coincidence judgment unit is noncoincidence, it is judged that switching is necessary if the switching parameter set by the parameter setting unit indicates immediate switching, A switch determination unit that determines that switching is necessary if the parameter indicates suppression switching, and the reception status is continuously incompatible with the broadcast system currently being viewed by the plurality of reception status information obtained over time, and the switching determination unit Is characterized by including a switching instruction unit for outputting a signal instructing switching of the broadcast system when it is determined that the switching is necessary.

  According to the present invention, it is possible to switch to a broadcast system according to the program genre, also taking into consideration the reception state.

It is a figure which shows the structure of the mobile receiver which concerns on Embodiment 1 of this invention. It is the table which extracted the classification of the program genre. It is the table which extracted the classification of the program genre. It is the table which extracted the classification of the program genre. It is the table which extracted the classification of the program genre. It is the table which extracted the classification of the program genre. It is the table which extracted the classification of the program genre. It is the table which extracted the classification of the program genre. It is the table which extracted the classification of the program genre. It is a table showing a switching parameter table. FIGS. 4A and 4B are diagrams showing an example of a hardware configuration of a control unit of the mobile receiver according to the first embodiment of the present invention. It is a flowchart which shows the process of the mobile receiver which concerns on Embodiment 1 of this invention. It is a flowchart which shows the process of the mobile receiver which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the mobile receiver which concerns on Embodiment 2 of this invention. It is a table showing a switching parameter table. It is a table showing a switching parameter table. It is a flowchart which shows a process of the mobile receiver which concerns on Embodiment 2 of this invention. It is a flowchart which shows a process of the mobile receiver which concerns on Embodiment 2 of this invention.

Hereinafter, in order to explain the present invention in more detail, a mode for carrying out the present invention will be described according to the attached drawings.
Embodiment 1
FIG. 1 shows a configuration diagram of a mobile receiver 1 according to Embodiment 1 of the present invention. In the following, mobile receiver 1 includes 1 segment broadcast (hereinafter referred to as 1 segment) which is a first broadcast scheme and 12 segment broadcast (hereinafter referred to as 12 segments) which is a second broadcast scheme. The case where the receiver is capable of receiving terrestrial digital television broadcast according to ISDB-T standard will be described as an example.

Although the first broadcast system, 1 segment, transmits low quality video and audio, it is suitable for reception while moving, and is a low-grade broadcast system compared to 12 segments. The second broadcast system, 12-seg, can transmit high-quality video and audio, but is not suitable for moving reception, and is a high-quality broadcast system compared to 1-seg. . Terrestrial digital television broadcasting according to the ISDB-T standard broadcasts programs having the same contents in 12 segments and 1 segment.
The mobile receiver 1 is mounted on a mobile and moves along with the movement of the mobile. The mobile object is, for example, a vehicle, a ship, an aircraft, a train, or a person who carries the mobile object receiver 1 and moves. Below, the case where the mobile receiver 1 is mounted in a vehicle is demonstrated to an example.

  The mobile receiver 1 includes a tuner unit 2, an orthogonal frequency division multiplexing (OFDM) demodulation unit 3, a control unit 4, a decoding unit 5, a storage unit 6, and an operation reception unit 7. The mobile receiver 1 is connected to the antenna 110, the output device 120, and the user control device 130. The connection between the mobile receiver 1 and the output device 120 and the connection between the mobile receiver 1 and the user operation device 130 are not limited to wired connections but may be wireless connections.

The antenna 110 receives a broadcast wave and outputs a reception signal to the mobile receiver 1.
The tuner unit 2 extracts a signal corresponding to a broadcast station of a program selected by the user from the reception signal output from the antenna 110, converts the signal into a digital signal, and outputs the digital signal to the OFDM demodulation unit 3.
The OFDM demodulation unit 3 OFDM demodulates the digital signal output from the tuner unit 2 and outputs TS (Transport Stream) to the control unit 4.

The control unit 4 separates the TS output from the OFDM demodulation unit 3 into video data, audio data, and additional information. The control unit 4 outputs the video data and the audio data to the decoding unit 5. Further, the control unit 4 extracts necessary additional information from the separated additional information, and stores the additional information in the storage unit 6. The additional information includes weather forecast, traffic information, subtitle information, etc. For example, when the mobile receiver 1 is a non-subtitle compatible model, subtitle information is not extracted as necessary additional information.
Details of the control unit 4 such as other processes performed by the control unit 4 will be described later.

The decoding unit 5 decodes the video data and the audio data output from the control unit 4 and outputs the decoded data to the output device 120.
The output unit 120 includes a display and a speaker, and provides the user with television video and television audio using the decoded video data and audio data output from the decoding unit 5.

  Selection of a program by the user is performed via the user operation device 130. The user operation device 130 outputs to the mobile receiver 1 a user operation signal indicating a broadcast station of a program which is operated by the user and which the user has selected to view. The user operation device 130 is, for example, an operation button or a touch panel integrally provided with the output device 120, or a remote control.

The operation reception unit 7 outputs the user operation signal output from the user operation device 130 to the control unit 4.
Here, the details of the control unit 4 will be described. The control unit 4 includes a reception processing unit 41, a parameter setting unit 42, a matching determination unit 43, a matching determination unit 44, a switching determination unit 45, a switching instruction unit 46, and a parameter reception unit 47.

The reception processing unit 41 outputs a control signal to the tuner unit 2 so as to select a broadcast station indicated by the user operation signal output from the operation receiving unit 7. After channel selection by the tuner unit 2, the reception processing unit 41 separates the TS output from the OFDM demodulation unit 3 into video data, audio data, and additional information. Then, the reception processing unit 41 outputs the video data and the audio data to the decoding unit 5, and stores necessary additional information in the storage unit 6. Further, the reception processing unit 41 extracts EIT (Event Information Table) information from the additional information, and outputs the EIT (Event Information Table) information to the parameter setting unit 42.
The EIT information includes information on the program genre. FIGS. 2A to 2H are tables which extract the classification of program genres defined in the terrestrial digital television broadcast of the ISDB-T standard.

The parameter setting unit 42 uses the EIT information output by the reception processing unit 41 to acquire the program genre being viewed. In addition, the parameter setting unit 42 sets a switching parameter corresponding to the program category being viewed as a switching parameter used for processing, using the switching parameter table.
The switching parameter table is stored in advance in the storage unit 6. FIG. 3 is a table showing an example of the switching parameter table. The switching parameter table is composed of a table T1 in which program genres are associated with switching parameters, and a table T2 in which switching parameters are associated with priority broadcast methods and switching types.
In the table T1 shown in FIG. 3, the switching parameter is set for each major category of the program genre, but the switching parameter may be set for each middle category even for program genres belonging to the same major category.

The switching parameters indicate, for example, a priority broadcast system and a switching type, as shown in the table T2. The priority broadcast system indicates a broadcast system to be viewed preferentially, and is set to either 12 segments or 1 segment.
For example, for a program category that is preferably viewed as high quality video such as "documentary / education", the priority broadcast system is set to 12 segments. On the other hand, in the program genre such as “news / news report” where it is preferable to place emphasis on reception continuity over image quality, the priority broadcast system is set to 1 segment.

  The switching type is set to either suppression switching or immediate switching. The suppression switching is a mode in which a continuous change of the reception state is considered in the determination of the switching. Immediate switching is a mode in which instantaneous changes in the reception state are taken into account in the determination of switching. The details of the switching type will be described in the process shown in FIG. 6 described later.

  The adaptation determination unit 43 uses the reception state information to determine whether the reception state conforms to the broadcast system being viewed. The reception status information is, for example, a packet error rate or a bit error rate that can be detected by the OFDM demodulation unit 3 in the process. The adaptation determination unit 43 performs the determination by comparing the packet error rate or the bit error rate with a preset first threshold. The first threshold value is near the boundary between the value that the packet error rate or bit error rate can take in the reception state suitable for 12 segments and the value that the packet error rate or bit error rate can take in the reception state suitable for 1 segment. Set to The determination result by the matching determination unit 43 is output to the matching determination unit 44.

  The coincidence determination unit 44 determines whether the broadcast system being viewed is in agreement with the priority broadcast system indicated by the switching parameter set as the switching parameter used by the parameter setting unit 42 for processing. The determination result by the match determination unit 44 is output to the switching determination unit 45.

  The switching determination unit 45 determines whether the switching is necessary in consideration of whether the switching type indicated by the switching parameter set as the switching parameter used for processing by the parameter setting unit 42 is the suppression switching or the immediate switching. . The determination result by the switching determination unit 45 is output to the switching instruction unit 46.

  When the switching determination unit 45 determines that the switching is necessary, the switching instruction unit 46 outputs a signal instructing switching from one broadcasting scheme currently being viewed to the other broadcasting scheme not being viewed. The signal is output to each unit of the mobile receiver 1, for example, to the decoding unit 5. This is because the coding format is different between 12 segments and 1 segment, so it is necessary to switch the decoding process corresponding to each format. Thus, for example, if the broadcasting method being viewed is 1 segment, the viewing mode is switched to 12 segments.

  The parameter receiving unit 47 receives the input of the switching parameter corresponding to the program genre by the user. For example, when the user desires by operating the user operation device 130, an image of the switching parameter table in which the cell X in FIG. 3 is blank is displayed on the output device 120, and the user can Enter one of them into cell X. Which switching parameter the user has selected is input as a user operation signal to the parameter receiving unit 47 via the user operation device 130 and the operation receiving unit 7. The parameter receiving unit 47 rewrites the switching parameter table stored in the storage unit 6 based on the user operation signal.

An exemplary hardware configuration of the control unit 4 will be described with reference to FIGS. 4A and 4B.
Each function of the reception processing unit 41, the parameter setting unit 42, the matching determination unit 43, the matching determination unit 44, the switching determination unit 45, the switching instruction unit 46, and the parameter receiving unit 47 of the control unit 4 is realized by a processing circuit. The processing circuit may be dedicated hardware or a CPU (Central Processing Unit) that executes a program stored in the memory. The CPU is also called a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, a processor, and a DSP (Digital Signal Processor).

  FIG. 4A is a diagram showing an example of a hardware configuration in the case where the functions of the respective units of the control unit 4 are realized by the processing circuit 100 which is dedicated hardware. The processing circuit 100 may be, for example, a single circuit, a complex circuit, a programmed processor, a parallel programmed processor, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a combination thereof. . The functions of the reception processing unit 41, the parameter setting unit 42, the matching determination unit 43, the matching determination unit 44, the switching determination unit 45, the switching instruction unit 46, and the parameter receiving unit 47 are realized by combining separate processing circuits 100. Alternatively, the function of each unit may be realized by one processing circuit 100.

  FIG. 4B is a diagram showing an example of a hardware configuration when the functions of the respective units of the control unit 4 are realized by the CPU 102 that executes a program stored in the memory 101. In this case, the functions of the reception processing unit 41, the parameter setting unit 42, the matching determination unit 43, the matching determination unit 44, the switching determination unit 45, the switching instruction unit 46 and the parameter receiving unit 47 are software, firmware, or software. It is realized by the combination with the firmware. Software and firmware are described as a program and stored in the memory 101. The CPU 102 realizes the functions of the respective units of the control unit 4 by reading and executing the program stored in the memory 101. That is, the control unit 4 has a memory 101 for storing a program or the like that results in execution of steps ST1 to ST23 shown in the flowcharts of FIGS. 5, 6, 10 and 11 described later. In addition, it can be said that these programs cause a computer to execute the procedure or method of each part of the control unit 4. Here, the memory 101 is, for example, a nonvolatile or volatile semiconductor such as a random access memory (RAM), a read only memory (ROM), a flash memory, an erasable programmable ROM (EPROM), and an electrically erasable programmable ROM (EEPROM). A memory, a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD (Digital Versatile Disc), etc. correspond.

  The functions of the respective units of the control unit 4 may be partially realized by dedicated hardware and partially realized by software or firmware. For example, the function of the reception processing unit 41, the parameter setting unit 42, the switching instruction unit 46, and the parameter receiving unit 47 is realized by a processing circuit as dedicated hardware, and the matching determination unit 43, the matching determination unit 44, and the switching determination The function of the unit 45 can be realized by the processing circuit reading and executing a program stored in the memory.

Thus, the processing circuit can realize each function of the control unit 4 by hardware, software, firmware, or a combination thereof.
The tuner unit 2, the OFDM demodulation unit 3, the decoding unit 5, and the operation reception unit 7 can also be configured as shown in FIGS. 4A and 4B, as in the control unit 4. The storage unit 6 is configured by a RAM or the like as the memory 101 described above.

Next, an example of processing by the mobile receiver 1 configured as described above will be described using the flowcharts shown in FIGS. 5 and 6.
FIG. 5 shows a process from when the user selects a desired program to view, until when switching parameters are set.
First, the reception processing unit 41 acquires a user operation signal output from the user operation device 130 operated by the user via the operation reception unit 7. Then, the reception processing unit 41 outputs a control signal to the tuner unit 2 to select a broadcast station indicated by the user operation signal (step ST1). At this time, the user operation signal also includes information as to which of the 12-segment and 1-segment broadcast modes the user desires to view. Alternatively, it may be set to automatically start viewing by either broadcast method by default.

Subsequently, the parameter setting unit 42 acquires the program genre being viewed using the EIT information output from the reception processing unit 41 (step ST2).
Subsequently, the parameter setting unit 42 reads and acquires the switching parameter table from the storage unit 6 (step ST3).
Subsequently, the parameter setting unit 42 extracts the switching parameter corresponding to the currently viewed program genre acquired in step ST2 from the switching parameter table acquired in step ST3 (step ST4).
Subsequently, the parameter setting unit 42 sets the switching parameter extracted in step ST4 as a switching parameter for the program being viewed (step ST5).
By these steps ST2 to ST5, the parameter setting unit 42 sets the switching parameter corresponding to the program being viewed as the switching parameter used for the process.

FIG. 6 shows a process performed after the process shown in FIG.
First, the adaptation determination unit 43 acquires reception state information from the OFDM demodulation unit 3 (step ST10). This process is performed periodically, for example, about once a second.
Subsequently, the suitability determination unit 43 determines whether the reception state indicated by the acquired reception state information conforms to the broadcast system being viewed (step ST11).

When the reception state conforms to the broadcast system being viewed (step ST11; YES), the process is ended without switching the broadcast system.
On the other hand, when the reception state is not compatible with the broadcast system being viewed (step ST11; NO), the match determination unit 44 sets the broadcast system being viewed to the priority broadcast system indicated by the switching parameter set in step ST5. It is determined whether there is a match (step ST12).

If the broadcast system being viewed matches the priority broadcast system (step ST12; YES), the process ends without switching the broadcast system.
On the other hand, if the broadcast system being viewed does not match the priority broadcast system (step ST12; NO), the switching determination unit 45 determines whether the switching type indicated by the switching parameter set in step ST5 is immediate switching Is determined (step ST13).
If the switching type is immediate switching (step ST13; YES), the switching determination unit 45 determines that switching of the broadcast system is necessary (step ST14). If it is determined by the switching determination unit 45 that switching of the broadcasting system is necessary, the switching instruction unit 46 outputs a signal instructing switching of the broadcasting system, and the broadcasting system is switched.

  On the other hand, when the switching type is the suppression switching (step ST13; NO), the switching determination unit 45 acquires reception state information for the set time (step ST15). That is, after the switching determination unit 45 acquires the reception state information from the OFDM demodulation unit 3 for the set time through the adaptation determination unit 43, the process proceeds to the next step ST16. Alternatively, the adaptation determination unit 43 may be configured to store the reception state information acquired from the OFDM demodulation unit 3 in the storage unit 6, and the switching determination unit 45 may set the history of the reception state information stored in advance. You may make it acquire reception status information for time.

  Subsequently, the switching determination unit 45 uses the plurality of reception state information for the set time obtained temporally in step ST15 to determine whether or not the reception state is incompatible with the broadcast system currently being viewed. (Step ST16). The switching determination unit 45 determines, for example, whether the packet error rate for the set time or the average value of the bit error rates is continuously nonconforming by comparing the average value with the second threshold. The second threshold may be the same as or different from the first threshold. Alternatively, whether the packet error rate or the bit error rate exceeds the first threshold or falls below the first threshold within the set time may determine whether the packet is continuously incompatible. Alternatively, whether the number of packet error rates or bit error rates exceeds or falls below the first threshold within the set time may be used to determine whether the status is nonconforming.

If the reception state is not continuously compatible with the broadcast system being viewed (step ST16; YES), the switching determination unit 45 determines that the broadcast system needs to be switched (step ST14). If it is determined by the switching determination unit 45 that switching of the broadcasting system is necessary, the switching instruction unit 46 outputs a signal instructing switching of the broadcasting system, and the broadcasting system is switched.
On the other hand, if it can not be said that the reception state is not consistently incompatible with the broadcast system being viewed (step ST16; NO), the process ends without switching the broadcast system.
That is, in the suppression switching, the broadcast system is switched if the reception status is incompatible with the broadcast system currently being viewed, but the broadcast system is not switched if the situation is instantaneous. On the other hand, in the case of immediate switching, the broadcasting system is switched even if the situation is instantaneous.
The processing described above with reference to FIG. 6 is periodically performed.

The control unit 4 may use the switching parameter table stored in the storage unit 6 as it is at the time of product shipment without providing the parameter receiving unit 47. The same applies to a second embodiment described later.
Further, in the above, the terrestrial digital television broadcast of the ISDB-T standard is taken as an example, and the first broadcast system is 1 segment and the second broadcast system is 12 segments. However, the mobile receiver 1 may receive the first broadcast system as CMMB (China Multimedia Mobile Broadcasting) and the second broadcast system as DTMB (Digital Terrestrial Multimedia Broadcast). The point is that the mobile receiver 1 is to switch between the first broadcasting method and the second broadcasting method of higher quality than the first broadcasting method by broadcasting a program having the same contents as the first broadcasting method. As long as it can The same applies to a second embodiment described later.

  As described above, the mobile receiver 1 according to the first embodiment determines which of the 12 seg and 1 seg broadcasting schemes the user is allowed to view based on only the program category being viewed. Also, the decision is made in consideration of the reception status. As a result, the mobile receiver 1 is switched to the 12-segment broadcast even when the reception state is poor, and, conversely, it is reduced to the program category while it is switched to the 1-segment broadcast even when the reception state is good. Since viewing according to the corresponding broadcast system is possible, the convenience for the user is good.

  Further, the parameter receiving unit 47 is provided to receive the input of the switching parameter corresponding to the program category by the user. Thereby, the user can set the switching parameter according to his / her preference.

  In addition, the first broadcasting method is one-segment broadcasting, and the second broadcasting method is twelve-segment broadcasting. Thus, the mobile receiver 1 can be used, for example, as a receiver for digital terrestrial television broadcasting according to the ISDB-T standard.

  In addition, it is assumed that the mobile receiver 1 is mounted on a vehicle. Thus, the mobile receiver 1 can be mounted on a vehicle and used.

Second Embodiment
In the first embodiment, the switching parameter is set corresponding to the program genre. In the second embodiment, the case where the switching parameter set corresponding to the program category is changed to the switching parameter corresponding to the vehicle information will be described.
FIG. 7 shows a configuration diagram of a mobile receiver 1 according to Embodiment 2 of the present invention. In addition, about the structure which has a function the same as that of the structure already demonstrated in Embodiment 1, or equivalent, the same code | symbol is attached | subjected, and the description is abbreviate | omitted or simplified.

The mobile receiver 1 is connected to the vehicle sensor 140.
The vehicle sensor 140 is, for example, an ECU (Electronic Control Unit), and outputs information indicating the position of the shift lever and the vehicle speed to the control unit 4.
The parameter setting unit 42 changes the switching parameter set corresponding to the program category being viewed to the switching parameter corresponding to the vehicle information as needed, and resets the switching parameter used for the process.

The storage unit 6 of the second embodiment stores a switching parameter table as shown in FIG. In the table T1, unlike the one shown in the first embodiment, vehicle information validity indicating whether or not to permit the change to the switching parameter corresponding to the vehicle information is set. Vehicle information validity is set for each program genre.
When the vehicle information validity is set to ON, the change to the switching parameter corresponding to the vehicle information is permitted. On the other hand, when the vehicle information validity is set to OFF, the change to the switching parameter corresponding to the vehicle information is not performed.

FIG. 9 is an example of a table T3 indicating switching parameters corresponding to vehicle information. Switching parameters are set according to the combination of the vehicle state, the vehicle speed, and the reception state. The reception state is included in the vehicle information because it is greatly influenced by where the vehicle is. For example, when the vehicle status is stopped and the reception status is good, the switching parameter A for which the priority broadcasting scheme is 12 segments corresponds, but when the vehicle status is stopping but the reception status is bad, the priority broadcasting scheme is 1 segment The switching parameter D corresponding to
The switching parameter table of the second embodiment is composed of tables T1 and T2 shown in FIG. 8 and a table T3 shown in FIG.
As in the first embodiment, the switching parameter corresponding to the vehicle information validity and the vehicle information can be changed by the user via the parameter receiving unit 47.

  Next, an example of processing by the mobile receiver 1 of the second embodiment configured as described above will be described using the flowcharts shown in FIG. 10 and FIG. The process shown in FIG. 10 is a process periodically performed after the process shown in FIG. 5 already described. Steps in which the same or corresponding processing as the processing already described with reference to FIG. 6 is performed are denoted with the same reference numerals, and the description thereof is omitted or simplified.

If the reception state is not compatible with the broadcast system being viewed (step ST11; NO), the parameter setting unit 42 performs a process of changing the switching parameter (step ST20).
FIG. 11 is a flowchart showing the details of step ST20.
First, the parameter setting unit 42 reads the switching parameter table from the storage unit 6, and determines whether the vehicle information validity corresponding to the program category being viewed is ON (step ST21).
When the vehicle information validity is OFF (step ST21; NO), the parameter setting unit 42 finishes the process of step ST20 without changing the switching parameter, and proceeds to step ST12.

  On the other hand, if the vehicle information validity is ON (step ST21; YES), the parameter setting unit 42 acquires the vehicle information (step ST22). The vehicle state included in the vehicle information indicates either stopping or traveling, and is based on the position of the shift lever that the vehicle sensor 140 outputs. The vehicle speed included in the vehicle information indicates low speed or high speed, and the vehicle speed output from the vehicle sensor 140 is compared with the third threshold to obtain whether the speed is low or high. . Further, the reception state included in the vehicle information is based on the reception state information output by the OFDM demodulation unit 3. That is, the parameter setting unit 42 compares the packet error rate or the bit error rate with the fourth threshold to obtain the quality of the reception state. The fourth threshold may be the same as or different from the first threshold.

Subsequently, the parameter setting unit 42 extracts a switching parameter corresponding to the vehicle information acquired in step ST22 using the switching parameter table, and resets the switching parameter as a switching parameter used for processing (step ST23).
After step ST23, the parameter setting unit 42 finishes the process of step ST20, and proceeds to step ST12. In the second embodiment, the processing after step ST12 is performed using the switching parameter set in step ST23.

  As described above, the mobile receiver 1 according to the second embodiment changes to the switching parameter corresponding to the vehicle information when the vehicle information validity is ON in addition to the processing described in the first embodiment. Do the processing. As a result, in addition to the effects of the first embodiment, it is also possible to view in a broadcast system according to the vehicle state, so convenience for the user is good.

  In addition, the parameter receiving unit 47 that receives the input of the switching parameter corresponding to the vehicle information by the user is provided. Thereby, the user can set the switching parameter according to his / her preference.

  In the scope of the invention, the present invention allows free combination of each embodiment, modification of any component of each embodiment, or omission of any component in each embodiment. is there.

  As described above, since the mobile receiver according to the present invention can switch to a broadcasting system according to the program genre in consideration of the reception state, for example, a receiver for receiving a terrestrial digital television broadcast according to ISDB-T standard It is suitable for being mounted on a vehicle etc.

  Reference Signs List 1 mobile receiver, 2 tuner unit, 3 OFDM demodulation unit, 4 control unit, 5 decode unit, 6 storage unit, 7 operation reception unit, 41 reception processing unit, 42 parameter setting unit, 43 conformity determination unit, 44 coincidence determination Unit 45 switching determination unit 46 switching instruction unit 47 parameter reception unit 100 processing circuit 101 memory 102 CPU 110 antenna 120 output device 130 user operation device 140 vehicle sensor.

Claims (7)

A mobile receiver that switches between a first broadcast system and a second broadcast system higher in quality than the first broadcast system that broadcasts a program having the same content as the first broadcast system,
A parameter setting unit configured to set, as a switching parameter used for processing, a switching parameter corresponding to a program category being viewed;
An adaptation determination unit that determines whether the reception state conforms to the broadcast system being viewed using reception state information;
A match determination unit that determines whether the broadcast method being viewed matches the priority broadcast method indicated by the switching parameter set by the parameter setting unit;
When the determination result by the conformity determination unit is nonconforming and the determination result by the coincidence determination unit is noncoincidence, if the switching parameter set by the parameter setting unit indicates immediate switching, it is determined that switching is necessary, and the switching parameter And a switching determination unit that determines that switching is necessary if the reception status is continuously incompatible with the broadcast system being viewed by the plurality of reception status information obtained over time, indicating the suppression switching.
A mobile receiver comprising: a switching instruction unit which outputs a signal instructing switching of a broadcasting system when the switching determination unit determines that switching is necessary.   The mobile receiver according to claim 1, further comprising a parameter receiving unit for receiving an input of a switching parameter corresponding to a program category by a user.   The parameter setting unit resets the switching parameter used for the process to the switching parameter corresponding to the vehicle information when the switching parameter set corresponding to the program genre can be changed to one corresponding to the vehicle information The mobile receiver according to claim 1, characterized in that:   4. A mobile receiver according to claim 3, further comprising a parameter receiving unit for receiving an input of a switching parameter corresponding to vehicle information by a user.   The mobile receiver according to claim 1, wherein the first broadcast system is a one-segment broadcast, and the second broadcast system is a 12-segment broadcast.   The mobile receiver according to claim 1, wherein the mobile receiver is mounted on a vehicle. A broadcasting method switching method of a mobile receiver, which switches between a first broadcasting method and a second broadcasting method higher in quality than the first broadcasting method that broadcasts a program having the same content as the first broadcasting method There,
A parameter setting step of setting, as a switching parameter used for processing, a switching parameter corresponding to a program category being viewed by the parameter setting unit;
An adaptation determination step of determining whether the adaptation status conforms to the broadcast system being viewed using the reception status information;
A coincidence judgment step of judging whether the coincidence judgment unit is in agreement with the priority broadcast system indicated by the switching parameter set in the parameter setting step;
The switching determination unit determines that switching is necessary if the switching parameter set in the parameter setting step indicates immediate switching if the determination result in the matching determination step is nonconforming and the determination result in the matching determination step is non-coincidence And the switching determination step of determining that switching is necessary if the reception state is continuously incompatible with the broadcast system being viewed by the plurality of reception state information obtained over time, and the switching parameter indicates suppression switching. ,
A broadcasting method switching method of a mobile receiver, comprising: a switching instruction step of outputting a signal instructing switching of a broadcasting system when the switching instruction unit determines that switching is necessary in the switching determination step. .

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