JP3290083B2 - Broadcast receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to, for example, DAB
(Digital Audio Broadcasti
ng: digital audio broadcasting).

[0002]

2. Description of the Related Art DAB has attracted attention as a radio broadcast format capable of coping with deterioration of sound quality due to interference due to multi-localization of FM broadcasting and difficulty in receiving good quality on a mobile body. DA
B is being developed by EUREKA (European Advanced Technology Development Plan) and has already been developed by the European Telecommunications Standard (European Telecom).
Standards are determined by the Standards of Standards, and a π / 4 shift D is used as a modulation method.
QPSK-OFDM (DifferentialQua
Drature Phase Shift Keyin
g-Orthogonal Frequency Di
(Vision Multiplex: Orthogonal Frequency Division Multiplexing), and is characterized by being less susceptible to fading and multipath.
Allocating one ensemble to the transmission bandwidth of 1 Hz
Each ensemble contains multiple service broadcasts,
Then, an audio program of a predetermined service broadcast of the selected ensemble is output as audio from a speaker or the like on the DAB radio.

In DAB, an interrupt service (Ann) such as an emergency broadcast (Alarm) or a traffic broadcast (Traffic) is provided.
If the predetermined type of interrupt service is input during the audio output of a service broadcast that permits interruption of the predetermined type of interrupt service, the audio program being output is interrupted and the interrupt service is interrupted. It is designed to output audio.

[0004]

During the audio output of the interrupt service, the user is provided with a service label (= service broadcast name) of the service broadcasting the interrupt service.
Can not know.

It is an object of the present invention to improve interrupt audio information.

[0006]

According to the present invention, there is provided a broadcast receiver (1).
In (0), a plurality of service broadcasts are included in one ensemble, an ensemble assigned to a predetermined band is received, and an audio program of one service broadcast is output as audio. The broadcast receiver (10) has the following (a) and (b). (A) Audio output switching means (40) for interrupting an audio program being output when interrupted audio information is present and outputting interrupted audio information as audio (b) (b) Displaying a service broadcast name of a service broadcast relating to interrupted audio information during interruption Service broadcast name display means (42)

[0007] Thus, when an interruption of the interruption audio information occurs, the user can know by which service broadcast the interruption audio information is performed.

According to another broadcast receiver (10) of the present invention,
The broadcast wave is a DAB broadcast wave.

According to another broadcast receiver (10) of the present invention,
The interrupt audio information is allocated to a predetermined sub-channel of the MSC and transmitted. The first FIG (FIG0 / 1
9), along with information indicating the transmission of interrupt audio information,
It has information on the sub-channel Id of the MSC sub-channel to which the interrupt audio information is assigned. Second F
The IG (FIG0 / 2), together with the service Id,
It has information on the sub-channel Id of the MSC sub-channel to which the audio data d is allocated. The audio output switching means (40) switches the audio output to the sub-channel Id based on the first FIG (FIG0 / 19). The service broadcast name display means (42) performs the service broadcast based on the service Id of the second FIG (FIG0 / 2) having the sub-channel Id information that matches the sub-channel Id information of the first FIG (FIG0 / 19). Find your name.

In this manner, the first FIG.
From the sub-channel Id information and the correspondence information between the service Id of the second FIG (FIG0 / 2) and the sub-channel Id, the service broadcast name of the service broadcast related to the interruption audio information broadcast can be smoothly determined. .

According to another broadcast receiver (10) of the present invention,
The interrupt audio information is an emergency broadcast or a traffic broadcast.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 2 is a system configuration diagram of the DAB radio 10 mounted on an automobile. The DAB radio 10 includes a main body 12, a DAB control microcomputer 26 separate from the main body 12, and the like. In the main body 12, the DAB system microcomputer 14
Has a memory 16 and a plurality of multiplex radio broadcast radio waves (hereinafter referred to as “ensemble”. The ensemble is a DQPS
A radio broadcast wave modulated by K-OFDM,
One ensemble has a bandwidth of about 1.5 MHz and usually includes six broadcast programs (each broadcast program is a sub-channel when the ensemble is a main channel). ) Is designated, and the designated information is sent to the RF block 18. RF block 18
Extracts the RF (Radio Frequency) of the ensemble specified by the DAB system microcomputer 14 and sends it to the demodulation block 20. In the demodulation block 20, R
The RF signal from the F block 18 is demodulated, and the channel decoding block 22 decodes the demodulated signal from the demodulation block 20. In this way, a digital signal of one ensemble designated by the DAB system microcomputer 14 to the RF block 18 is obtained in the channel decoding block 22. Of the digital signals decoded in the channel decoding block 22, audio data is sent from the channel decoding block 22 to the audio decoding block 24, and F
IG (Fast information Group)
p) The data is sent from the channel decoding block 22 to the DAB system microcomputer 14. Audio decoding block 24
Decodes the audio data of the sub-channel specified by the DAB system microcomputer 14 from among the audio data input from the channel decoding block 22, and sends the decoded audio data to left and right speakers (not shown). PAD (Program Associate)
d Data: data related to audio data)
To the DAB system microcomputer 14. The DAB control microcomputer 26 has a memory 28 and exchanges data with the DAB system microcomputer 14 of the main body 12. The DAB control microcomputer 26 receives instructions from the user via the key 30 and outputs predetermined data to the display 32 to display information to inform the user.

In FIGS. 3 to 8, communication protocols of various elements of the DAB such as a transmission frame are described as appropriate. For details, see the European Telecommunications Standards Association (European Telecommunications).
indications Standards Instiu
te) issued by the European Telecommunications Standard (European Telecommunications)
ionics Standard).

FIG. 3 shows the structure of a DAB transmission frame. Transmission frame (Trans mission fra
me) are the synchronization channels (Synchron
iZation Channel), FIC (Fast)
Information Channel) and MS
C (Main Service Channel). The FIC further includes a plurality of FIBs (Fast I
The MSC further includes a plurality of CIFs (Common Interleave).
saved frame). DAB mode 1
The specification is determined from mode to mode 3, and the mode (duration) of the transmission frame and the number of FIBs and CIFs in one transmission frame are different for each mode. For example, in mode 1, the time of one transmission frame is 96
ms, the number of FIB and CIF in one transmission frame is 12 and 4, respectively.

FIG. 4 is an exemplary diagram of a DAB service structure. Ensemble label is DAB Ensemble 1 (DA
B ENSEMBLE ONE) is an ensemble (Ensemble) whose service label is alpha1.
Radio (ALPHA1 RADIO), Beta Radio (BETA RADIO), Alpha 2 Radio (ALP)
HA2 RADIO) and other services (Servi
ce). The user hears the selected service from the DAB radio 10.

The alpha 1 radio has one main service component (Service components) and two sub service components. The main service component is audio, and the secondary service component is a traffic message channel: TMC (Traf).
fic Message Channel and service information: SI (Service Information)
It is. The audio component and the SI are transmitted on separate sub-channels (SubCh) in the MSC, and the TMC is transmitted in a FIDC (Fast Information Da) in the FIC.
ta Channel).

Beta radio has two service components.
Audio and secondary audio (secondary a
audio component), both of which are MS
On the C subchannel.

The alpha 2 radio has the same TMC and SI as the alpha 1 radio, and the audio may be the same as the alpha 1 radio depending on the switching.

FIG. 5 is a structural diagram of the FIB. FIB is a 30-byte FIB data area (FIB d
data field) and a 16-bit CRC (Cycle)
icRedundancy Check). F
The IB data area is a valid data area (us
eful data field), an end marker indicating the end of the valid data area (End marker),
And padding for making the number of bits of the FIB data area equal to the set value. The valid data area includes a plurality of FIGs (Fast info).
migrationGroup). Each FIG is a FIG header (FIG header) and a FIG data area (FIG data field) in order from the front. The FIG header has a 3-bit FIG type (FIG type) indicating the type of FIG in order from the front.
e) and a 5-bit length (L
length). . In addition, as shown in FIG type and length, 8 bits in each byte are hereinafter referred to as b7,
b6,... b0 are defined.

FIG. 6 is a structural diagram of the FIG. 0 FIG. The FIG data area includes an extension (Ex
tension or type 0 area (Type 0 fi)
eld).

FIG. 7 shows a FIG having a FIG type of 0 and an extension of 19 (hereinafter, the FIG type and the extension are represented by “FIG type / extension”. In the case of FIG of FIG. 7, the representation of FIG 0/19 is shown. FIG. 4 is a structural diagram of a type 0 area of FIG. The type 0 area includes a plurality of interrupt service switching: Asw (Ann
ounce switching). Each interrupt service switching includes, in order from the beginning, an Asw flag (Asw flags) indicating which interrupt service type is valid or invalid, and a cluster Id (Cluste) indicating a cluster Id of the interrupt service switching.
r Id), currently undefined Rfa, last byte of this interrupt service switching (the last byte is 2 bits Rfa and 6 bits RegionId Lower
part. ) Indicates whether or not there is data, and an audio service component (audio service) for transmitting an interrupt service related to the interrupt service switching.
component = interrupt audio information) is MS
Subchannel Id indicating which subchannel of C is in
(SubChId), the currently undefined Rfa, and the region Id lower part indicating the region of this interrupt service switching (RegionId Lower part). Each type of interrupt service is assigned to each of the b15 to b0 of the Asw flag. Currently, b0 is an emergency broadcast (Alarm), b1 is a traffic broadcast (Traffic), and when the flag is 1, the Asw is the Asw flag. This means that an interrupt service of the type is being transmitted on the sub-channel designated by the sub-channel Id.

FIG. 8 is a structural diagram of a type 0 area of FIG0 / 2. FIG. 0/2 indicates basic information of each service included in one ensemble. Each service area includes a service Id (SId) and a sub-channel Id for transmitting audio data of the service Id.
(SubChId).

FIG. 1 is a flowchart of the interrupt service routine. In step S10, it is determined whether or not FIG0 / 19 has been detected.
Proceed to 2 and if not detected, end the routine.
Emergency broadcasting (Alarm) and traffic broadcasting (Traffic)
If an interrupt service such as
There are nineteen . In step S12, it is determined whether or not there is a request for an interrupt service.
If not, the routine ends. FIG0 /
If the Asw flag 19 is 1 and the service that is currently outputting audio belongs to the cluster of the cluster Id of FIG0 / 19, it is determined that an interrupt service request has been issued. In step S14, the audio data of the interrupt service is extracted and decoded from the sub-channel of the MSC indicated by the sub-channel Id of FIG0 / 19, and is output to a speaker (headphone or the like in some cases).
In step S16, the subchannel I of FIG0 / 19
From d, the service Id relating to the sub-channel Id is detected. The DAB radio 10 receives the FIG. 0/2 service Id and its service I
The correspondence of the subchannel Id of the service d is stored in the memory 16. However, the number of storages of the correspondence relation between the service Id and the sub-channel Id is equal to or less than a predetermined value due to the restriction on the capacity of the memory 16. Therefore, the detection of the service Id in step S18 can be performed based on the memory contents stored based on FIG0 / 2. Step S
At 18, it is determined whether or not the service Id has been detected,
If detected, the process proceeds to step S20; otherwise, the routine ends. In step S20, a service label (= service broadcast name) as a service broadcast name corresponding to the service Id is detected. DAB
The radio 10 has a predetermined correspondence table between the service ID and the service label in the memory 16 in advance. Step S22
Then, it is determined whether or not the service label has been detected from the correspondence table. If the service label can be detected, the process proceeds to step S24, and if not, the routine ends. In step S24, the detected service label is displayed on the display 32.

The audio output switching means 40 switches the audio output to the interrupt service based on the interrupt service request, and corresponds to step S14. The service broadcast name display means 42 detects the service label of the service transmitting the interrupt service and displays the service label on the display 32, and corresponds to step S24.

[Brief description of the drawings]

FIG. 1 is a flowchart of an interrupt service routine.

FIG. 2 is a system configuration diagram of a DAB radio mounted on an automobile.

FIG. 3 is a diagram showing a structure of a DAB transmission frame.

FIG. 4 is an exemplary diagram of a DAB service structure;

FIG. 5 is a structural diagram of an FIB.

FIG. 6 is a structural diagram of an FIG having a FIG type of 0;

FIG. 7: FIG type 0 and extension 1
9 is a structural diagram of a type 0 region of FIG. 9; FIG.

FIG. 8 is a structural diagram of a type 0 region of FIG0 / 2.

[Explanation of symbols]

 Reference Signs List 10 DAB radio (broadcast receiver) 40 Audio output switching means 42 Service broadcast name display means

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Claims (4)

(57) [Claims] 1. A transmission frame of the broadcast radio wave including a plurality of service has a sub-channel audio data is decoded, the broadcast radio wave, information indicating the transmission of the interrupt audio information (hereinafter, "first Information "), information on the sub-channel Id of the sub-channel to which the interrupt audio information is allocated (hereinafter, referred to as" second information "), and correspondence information between the service Id and the sub-channel Id (hereinafter," second information "). , "Third information") in a broadcast receiver for receiving the broadcast radio wave, a memory for storing a correspondence table between a service Id and a service label as a service broadcast name; Audio output switching means for interrupting an audio program being output if present, and outputting interrupt audio information as audio, based on the second and third information Means for detecting a service Id corresponding to the sub-channel Id of the sub-channel from which audio data of the interrupt service is extracted; means for detecting a service label corresponding to the detected service Id from the correspondence table; and displaying the detected service label. A broadcast receiver, comprising: 2. The broadcast receiver according to claim 1, wherein the broadcast wave is a DAB broadcast wave. 3. The broadcast receiver according to claim 2, wherein said first, second and third information are included in FIG. 4. The broadcast receiver according to claim 2, wherein the interrupt audio information is an emergency broadcast or a traffic broadcast.