JP2003153113A - Broadcasting receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a broadcasting receiver by which the video of analog broadcasting in the same program can be displayed when it is difficult to receive digital broadcasting without any complicated operation. SOLUTION: In the broadcasting receiver 30, the tuning information of an analog broadcasting channel can be registered in a memory 12 beforehand corresponding to a digital broadcasting channel. When a C/N is lower than a threshold and a low-hierarchy program is not present during receiving of the digital broadcasting channel, in the broadcasting receiver 30, the information of the analog broadcasting channel corresponding to the relevant digital broadcasting channel is read out of the memory 12, an analog tuner 11 is controlled, and the display of video in the same program of analog broadcasting is tried.

Description

Detailed Description of the Invention

The present invention relates to a broadcast receiver capable of receiving both digital broadcast and analog broadcast.

[0002]

2. Description of the Related Art For example, in a digital broadcast receiving system using a satellite, a video / audio signal is compressed using a digital signal compression technique and a stream (trans) in which video / audio digital signals of a plurality of programs are time-division multiplexed. The port stream) is broadcast via a transponder (satellite repeater). On the other hand, a broadcast receiving apparatus for receiving such a digital broadcast selects one of a plurality of transponders of a digital broadcast received through an antenna with a tuner, and selects one of a plurality of channels included in this one transponder. Is selected by demultiplexing, and the digital signal of the selected channel is decoded to output a video / audio signal.

Further, in such a digital broadcasting receiving system, since transmission can be made by combining different modulation methods, hierarchic transmission can reduce the interruption time due to rain attenuation or transmission system failure. here,
The mechanism of hierarchical transmission will be briefly described. As shown in FIG. 3, when layered transmission is performed in digital television broadcasting using broadcasting satellites, the transmitting side is TC8PS.
High-layer transmission for transmitting high-quality information according to the K modulation method and low-layer transmission for transmitting low-quality information according to the BPSK modulation method are transmitted in parallel in a form in which each stream area is divided. In a normal reception state, the receiving device can receive services of both the higher layer and the lower layer, and normally reproduces the higher layer transmission service information. On the other hand, when the reception C / N level is lowered due to rain attenuation or the like, only the lower layer transmission service can be received, and the lower layer information is reproduced.

In the layered transmission service, these plural transmission methods are combined by the time division multiplexing method, and the video of the same information is transmitted simultaneously in parallel in the high layer transmission and the low layer transmission. When the received C / N level is high, high quality transmission can be selected, and when the received C / N level is low, low quality transmission can be selected to perform decoding. As a result, reception can be continued even if the received electric field strength decreases, and the reception time ratio can be improved.

In the digital broadcast receiving apparatus corresponding to the above-mentioned layered transmission, the demodulation section monitors the error status of the data when receiving the higher layer transmission. When the attenuation of received radio waves becomes large due to the influence of rainfall and the error rate exceeds a predetermined threshold, the broadcast reception is continuously maintained by automatically switching to a lower hierarchy information program.

FIG. 4 is a block diagram showing a schematic configuration of a conventional digital broadcast receiving apparatus. The digital broadcast wave received by the antenna 1 is frequency-converted by the tuner 2 and then demodulated by the demodulation unit 3, and the error correction unit 4
By this, error correction processing is performed and a transport stream is generated. The generated transport stream is separated and decoded by the TS separation decoding unit 5, the AV decoder 6 restores the video signal and the audio signal, and is output to the TV monitor 21. The control unit 9 is responsible for controlling the entire receiving device.

Further, the BER detection unit 7 constantly monitors the error rate (bit error rate), and the switching signal generation unit 8 hierarchizes the AV decoder 6 when the error rate exceeds a predetermined threshold value. Generate a switching signal. At this time, the AV decoder 6 switches the decoding target to the lower layer transmission information and executes the output processing. The predetermined threshold value is a preset threshold value that includes a margin in the limit value of the error rate when the transmitted signal cannot be restored.

[0008] Also, when receiving a lower layer transmission,
When the error rate monitored by the BER detection unit 7 is recovered to be equal to or lower than a predetermined threshold value, the switching signal generation unit 8 performs a process of returning to decoding of the higher layer transmission information.

[0009]

However, whether or not to carry out layered transmission is arbitrarily decided by the broadcaster,
Some programs may not be hierarchically transmitted, and in such a case, it may not be possible to watch the broadcast during rain.

On the other hand, analog broadcasting has the property that the reception state gradually deteriorates, not that it cannot be viewed suddenly. Therefore, there may be a case where viewing by analog broadcasting is possible even though viewing by digital broadcasting is not possible. Here, BS (Broadcasting)
In the "Via Satellite" broadcast, analog broadcast and digital broadcast are scheduled to broadcast the same program by simulcast. If broadcasting is performed by this simulcast and the receiving device is configured to be able to receive both digital broadcasting and analog broadcasting, when it becomes difficult to receive video / audio while watching digital broadcasting, the user himself / herself It is possible to continue to watch the same program by operating the remote control device to switch to reception of analog broadcast.

However, depending on the user, C /
It is often difficult to know what to do when the video / audio cannot be viewed at all due to the deterioration of N. Further, when the user switches to the analog broadcast reception, there is a possibility that the analog broadcast may be continuously watched even though the reception level of the digital broadcast is recovered.

In view of the above circumstances, an object of the present invention is to provide a broadcast receiving apparatus capable of receiving an analog broadcast of the same program when it is difficult to receive a digital broadcast without a troublesome operation.

[0013]

In order to solve the above-mentioned problems, a broadcast receiving apparatus of the present invention has an analog broadcast receiving section for receiving analog broadcast, a digital broadcast receiving section for receiving digital broadcast, and a digital broadcast. Reception quality detection means for detecting the reception quality of, the registration means capable of pre-registering the analog broadcast channel corresponding to the digital broadcast channel, and when the reception quality falls below a predetermined level during reception of the digital broadcast, If an analog broadcast channel corresponding to the digital broadcast channel is registered, the control means for executing the received video display of the analog broadcast channel is provided.

With the above configuration, when analog broadcasting and digital broadcasting are broadcasting the same program by simulcast, the simulcast analog broadcasting channel can be registered in advance in association with the digital broadcasting channel. it can. Then, when the reception level falls below the predetermined level while watching the digital broadcast,
Since the reception is automatically switched to the analog broadcasting, the user can continuously view the same program without any troublesome operation.

When the received video display of the analog broadcast channel corresponding to the digital broadcast channel is executed, the two-screen display process is performed by continuing the received video display of the digital broadcast channel to watch which broadcast channel. It may be configured so that the user can select whether or not. According to this, it is possible to select which channel to watch based on the intention of the user.

After switching to the video display of the corresponding analog broadcast channel, when the recovery of the digital broadcast reception level is detected, it is preferable that the video display of the original digital broadcast channel is restored. According to this, it is possible to prevent a problem that the analog broadcast is continuously watched regardless of the reception level of the digital broadcast being recovered.

It is preferable that the user can perform a process of pre-registering the analog broadcast channel corresponding to the digital broadcast channel. Here, although the above registration process can be performed on the manufacturer side, a channel for performing a new simulcast may appear after the broadcast receiving device is shipped. For such a new channel, registration by the user is required. It will be possible.

When the reception quality is lower than a predetermined level during reception of the digital broadcast and there is no low-level broadcast, the reception video display of the analog broadcast channel corresponding to the digital broadcast channel is executed. Good.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
2 and the description will be made based on FIG.
(Broadcasting via Satelli
te) illustrates the case of viewing a broadcast. Figure 1 BS
FIG. 2 is a block diagram showing a broadcast receiving device 30 of this embodiment capable of viewing both digital broadcast and BS analog broadcast, and FIG. 2 is a flowchart showing a broadcast reception switching process.

In FIG. 1, an antenna 1 is arranged outdoors in a predetermined direction and receives a digital broadcast wave transmitted from a satellite. If the digital BS is launched on the same orbit as the analog BS, one antenna 1 can be shared. The tuner 2 extracts a signal of a specific frequency from the received high frequency digital modulation signal. This signal is demodulated by the demodulation unit 3 and error-corrected by the error correction unit 4 to output a transport stream.

The TS separation / decoding unit 5 converts the transport stream into MPEG2 (Moving Picture).
e Experts Group 2) video stream, audio stream, and PSI / SI (Pr
ogram Specific Information
n / Service Information). The TS separation decoding unit 5 supplies the video stream and the audio stream to the AV decoder 6, and the PSI
The service information (program name, program details, program start time, program duration, etc.) included in / SI is supplied to the control unit (microcomputer) 9. As described above, a plurality of channels are multiplexed in the transport stream, and the process for selecting an arbitrary channel from this is performed by selecting any channel from PSI / SI in the transport stream. This can be done by extracting data such as which packet ID is used for multiplexing. Also, the selection of the transport stream is PSI.
/ SI can be performed based on the information.

The AV decoder 6 includes a video decoder for decoding a video stream and an audio decoder for decoding an audio stream. The video decoder decodes the input variable length code to obtain a quantized coefficient and a motion vector, and performs inverse DCT conversion and motion compensation control based on the motion vector. The audio decoder decodes the input coded signal to generate audio data. The generated video data and audio data are D /
A-converted into an analog AV signal, which is supplied to the TV monitor 21 via the video selection switch 14.

The video selection switch 14 receives the analog AV signal from the AV decoder 6 and the analog tuner 11.
From the output source switching signal generator 10 and outputs one of the analog AV signals based on the instruction signal from the output source switching signal generator 10. The analog tuner 11 performs a channel selection process for selecting a signal of a frequency corresponding to the channel selected by the user and a demodulation process for FM demodulating the signal of the selected frequency. Then, for video processing, de-emphasis processing is performed to generate a video signal, and for audio processing, PCM demodulation processing or D / D processing is performed.
A conversion processing is performed to generate an analog audio signal.

The BER detector 7 acquires information on the presence or absence of an error from the error corrector 4, calculates an error rate (bit error rate), and supplies this to the switching signal generator 8. The switching signal generation unit 8 determines whether or not the error rate exceeds a predetermined threshold value, and when the error rate exceeds the predetermined threshold value, gives the AV decoder 6 an instruction to decode a signal of a lower hierarchy. When the AV decoder 6 receives the instruction, it decodes the lower layer signal, but if there is no lower layer signal, it returns a signal to that effect to the switching signal generator 8. The threshold value for determining layer switching is not specified in particular, but is a matter of specifications of each receiving device.

Upon receiving the signal indicating that there is no lower hierarchy, the switching signal generator 8 gives a switching instruction to the output source switching signal generator 10. When the output source switching signal generator 10 receives the switching signal,
The switching operation is executed so as to output the analog AV signal from the analog tuner 11.

User I / F (interface) 13
Is, for example, a light receiving unit that receives infrared rays from a remote control transmitter (not shown), or switches provided in the main body of the device 30. Information obtained by the user operating the remote control transmitter or the like is given to the control unit 9 via the user I / F 13.

The control unit 9 controls the broadcast receiving apparatus 30 as a whole, and in particular, as a process according to the present invention, it performs a reception execution process relating to simulcast. That is, the control unit 9 reads out information (such as channel selection information of corresponding analog channels) regarding the simulcast of the program (channel) corresponding to the program (channel) received by the digital tuner 2 from the memory 12, and The analog tuner 11 is caused to perform a tuning operation based on the information. When the information regarding the simulcast does not exist in the memory 12, the output source switching signal generation unit 10 is given a maintenance command in order to continue the digital broadcast reception.

As described above, the memory 12 stores information about simulcast. However, this information can be stored in advance within a range known at the time of shipment of the broadcast receiving apparatus 30, or by the user. It can also be stored by the input operation of. In the latter case, the user knows the existence of an analog broadcast channel corresponding to a certain digital broadcast channel by a newspaper or the like, and, for example,
The simulcast setting screen can be called up from the menu screen, and an analog broadcast channel can be made to correspond to a certain digital broadcast channel, such as "digital (101) → analog (11)" on this screen.

FIG. 2 is a flow chart showing the simulcast reception execution processing in the broadcast receiving apparatus 30.
It should be noted that this flow chart shows an example of a processing mode that goes through a two-screen display state. In the high-level video display state of digital broadcasting (step S1), the reception quality (here, the C / N ratio is used. The C / N ratio and the error rate are correlated, and both indicate the reception quality (reception level). Is lower than the threshold value (step S2), and if lower than the threshold value, it is determined whether or not there is a low layer transmission program (step S3). If there is a low hierarchy program, it is switched to the low hierarchy program and video is displayed (step S10). Then, it is determined whether or not the reception quality has recovered to a threshold value or higher (step S12), and if recovered, the digital broadcast high-layer video display state is set (step S1).

If there is no lower hierarchy program in step S3, it is judged whether or not the corresponding analog channel exists in the simulcast based on the information stored in the memory 12 (step S4). If there is no corresponding analog channel, the high-level video display state of digital broadcasting is maintained (step S11). Here, it is assumed that the state in which the reception quality is below the threshold does not indicate the state in which error correction is difficult, but the state in which error correction is likely to become difficult. Therefore, it does not mean that high-level video display of digital broadcasting cannot be performed, and the high-level video display is being executed in a state in which there is a high possibility of being unviewable.

On the other hand, if there is a corresponding analog channel, the screen of the monitor 21 is switched to the two-screen display,
High-level video of digital broadcasting is displayed on one of the two screens and received video of an analog channel is displayed on the other of the two screens (step S5). Through this processing, the user (viewer) can select the one he / she likes by viewing both screens. If the user does not select analog broadcasting (NO in step S6), the high-level video display state of digital broadcasting is maintained (step S11). If the user selects analog broadcasting (YES in step S6),
The analog broadcast image is displayed (step S7), and it is judged whether the reception quality has recovered to a threshold value or more (step S12). If it does not recover, the analog broadcast image display is maintained, and if it recovers, the digital broadcast is received. (Step S9), the high-level video display state is set (step S9).
1).

As described above, when the analog broadcast and the digital broadcast are broadcasting the same program by simulcast, the information about this is stored in the memory 12 by the registration operation by the user (or by the maker). Therefore, when the reception level falls below a predetermined level during viewing of a digital broadcast and there is no low-level broadcast, the broadcast receiving device 30 automatically performs the analog broadcast based on the information stored in the memory 12. The process of switching to reception can be executed. This allows the user to continuously view the same program without any troublesome operation.
Further, the broadcast receiving apparatus 30 switches to reception of the simulcast analog broadcast, and then switches to reception of the simulcast digital broadcast when the recovery of the reception level is detected, so that the reception level of the digital broadcast is recovered. Regardless, (even though high-level video can be displayed), it is possible to prevent you from continuing to watch analog broadcasts.

It is to be noted that power is saved by not energizing the analog tuner 11 until it is determined in step S4 that there is a corresponding analog broadcast. Also, in the above example, it was decided to switch to simulcast analog broadcast reception before the digital broadcast reception became impossible, but the invention is not limited to this, and it is possible to switch to simulcast analog broadcast reception after the digital broadcast reception becomes impossible. Good.
Also, when switching to analog broadcast reception of simulcast, a message indicating that the analog broadcast reception has been switched may be displayed on the screen. Further, in the above-mentioned two-screen display, it may be displayed which is an analog broadcast and which is a digital broadcast. Further, the two-screen display may be a low-level video display or an analog broadcast video, and the user can select either of these.

[0034]

As described above, according to the present invention, the analog broadcast of the same program can be received when it is difficult to receive the digital broadcast without a troublesome operation. Further, there is an effect that it is possible to prevent the analog broadcast from being continuously watched regardless of the reception level of the digital broadcast being recovered.

[Brief description of drawings]

FIG. 1 is a block diagram showing a broadcast receiving apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an automatic reception switching process for simulcast according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram of a hierarchical transmission system.

FIG. 4 is a block diagram showing a conventional digital broadcast receiving apparatus.

[Explanation of symbols]

1 antenna 2 tuner 3 demodulator 4 Error correction section 5 TS separation and decoding unit 6 AV decoder 7 BER detector 8 Switching signal generator 9 control unit 10 Output source switching signal generator 11 analog tuner 12 memories 13 User I / F section 14 switch

Claims (5)

[Claims] 1. An analog broadcast receiving section for receiving analog broadcasts, a digital broadcast receiving section for receiving digital broadcasts, a reception quality detecting means for detecting reception quality of the digital broadcasts, and analog broadcasts corresponding to digital broadcast channels. A registration means capable of pre-registering a channel and, when the reception quality falls below a predetermined level during reception of a digital broadcast, if the analog broadcast channel corresponding to the digital broadcast channel is registered, the analog broadcast A broadcast receiving apparatus, comprising: a control means for displaying a received image of a channel. 2. The broadcast receiving apparatus according to claim 1, wherein when the received video display of the analog broadcast channel corresponding to the digital broadcast channel is executed, the received video display of the digital broadcast channel is also continued. A broadcast receiving device characterized by being configured so that a user can select which broadcast channel to view by performing screen display processing. 3. The broadcast receiving apparatus according to claim 1 or 2, when the recovery of the digital broadcast reception level is detected after switching to the video display of the corresponding analog broadcast channel, the video of the original digital broadcast channel is detected. A broadcast receiving device characterized by being configured to return to a display. 4. The broadcast receiving apparatus according to any one of claims 1 to 3, wherein the user can perform a process of pre-registering an analog broadcast channel corresponding to a digital broadcast channel. A broadcast receiving device characterized by. 5. The broadcast receiving apparatus according to any one of claims 1 to 4, wherein the reception quality is below a predetermined level during reception of the digital broadcast, and there is no low-layer broadcast, the digital broadcast channel. A broadcast receiving apparatus characterized by being configured to execute reception video display of an analog broadcast channel corresponding to.