JPH11331004A - Digital broadcast recording system and digital radio broadcast recording system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow an audio recording and reproducing device to properly select a radio broadcast program (= service component) in a same ensemble of a DAB independently of a DAB receiver in the DAB broadcast recording and reproducing system. SOLUTION: An RDI frame encoder 18 of a DAB receiver 11 generates an RDI frame from a DAB transmission frame, a digital interface transmitter 19 generates an IEC958 sub-frame from the RDI frame and outputs it to a digital interface cable 14. A digital interface receiver 24 of an audio recording and reproducing device 12 extracts the RDI frame from the IEC958 sub-frame received from the digital interface cable 14, and an RDI frame decoder 25 extracts an FIC and an MSC from the RDI frame. Thus, a sub-channel relating to an instructed radio broadcast program is extracted and decoded from the MSC and signal-processed for recording on a recording medium such as an MD and the processed signal is recorded thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to, for example, DAB
(Digital Audio Broadcasti
The present invention relates to a digital broadcast recording system and a digital radio broadcast recording system including a receiver for receiving digital broadcasts such as digital audio broadcasts (ng: digital audio broadcast). More specifically, a plurality of broadcast programs are allocated to a plurality of channels and carried by a common transmission frame. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital broadcast recording system and a digital radio broadcast recording system in which the recording of incoming digital broadcast programs is improved.

[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 has been developed by EUREKA (European Advanced Technology Development Plan), and its specifications have already been defined. As a modulation method, π / 4 shift DQPSK-OFDM is used.
(Differential Quadrature
Phase Shift Keying-Orthog
onal Frequency DivisionMu
ltiplex: orthogonal frequency division multiplexing), which is characterized by being less susceptible to fading and multipath.
Using the PEG layer II, a large number of stereo broadcasts and data broadcasts are enabled with a transmission bandwidth of 1.5 MHz. D
In the AB, a plurality of broadcast programs broadcast simultaneously are allocated to different channels in a common transmission frame and broadcast.

[0003] In a conventional DAB broadcast recording / playback system for recording a DAB radio broadcast program, a receiver includes:
Extracting a digital signal related to a predetermined radio broadcast program,
The digital signal is transmitted from the receiver to the recorder, and the recorder records the digital signal.

[0004]

In the conventional DAB broadcast processing system, the entire DAB broadcast processing system
The radio broadcast program to be recorded or listened to is determined by the selection in the receiver, and the recorder cannot appropriately select the audio data extraction unit for processing the recording and the like. In particular, when there are a plurality of system components such as recorders that process DAB radio broadcast programs, it is difficult to process different radio broadcast programs.

An object of the present invention is to provide a digital broadcast recording system which can overcome the above-mentioned problems.

[0006]

SUMMARY OF THE INVENTION A digital broadcast recording system (10) of the present invention comprises: (a) a plurality of broadcast programs broadcast simultaneously allocated to different channels in a common transmission frame and broadcast; It has a receiver (11) for receiving a digital broadcast signal, and (b) a processor (12, 13) for processing a broadcast program received by the receiver (11). In this digital broadcast recording system (10), the receiver (11)
Outputs a digital signal including a plurality of channels before extracting a predetermined channel to the digital interface cable (14). The processors (12, 13) select and extract a predetermined broadcast program from the digital signal input from the digital interface cable (14), and perform processing on the extracted broadcast program.

[0007] The "digital signal including a plurality of channels before extracting a predetermined channel" is the "digital signal including at least two channels out of all channels before extracting a predetermined channel". It means “digital signal including all channels before extracting a predetermined channel”.

[0008] Broadcast programs are not limited to radio broadcast programs, but also include television broadcast programs. The processors (12, 13) are usually recorders (12) for radio broadcast programs, and are recorders / recorders for television broadcast programs. But,
The processing machines (12, 13) are not limited to the recording machines (12, 13), and may be monitors, speakers, amplifiers, and the like. The number of processors (12, 13) connected to the receiver (11) via the digital interface cable (14) is not limited to one, but may be plural.

In the receiver (11), a digital signal including a plurality of channels is output from the receiver (11) to the digital interface cable (14). The processing machines (12, 13)
A channel related to a predetermined broadcast program is selected and extracted from a digital signal input via a digital interface cable (14), and processing such as recording is performed on the extracted broadcast program. In this way, for a digital broadcast signal in which a plurality of broadcast programs broadcast at the same time are allocated to different channels in a common transmission frame and broadcast, the selection of the broadcast program to be processed is not the receiver (11) but the receiver (11). Since the processing is performed in the processing device (12, 13) at the processing destination that performs the actual processing, it is convenient when the broadcast program processed by the processing device (12, 13) is appropriately changed. In particular, a plurality of processors (12, 13) are connected to the digital interface cable (14).
Connected to a common receiver (11) via
This is advantageous because each processor (12, 13) can select and process a different broadcast program.

A digital radio broadcast recording system (10) according to the present invention comprises: (a) a digital radio broadcast signal in which a plurality of simultaneously broadcast radio broadcast programs are allocated to different channels in a common transmission frame and broadcast; And (b) a recorder (12) for recording a radio broadcast program received by the receiver (11). In this digital radio broadcast recording system (10), the receiver (11) uses the audio program part and the management information in the transmission frame extracted from the received signal as the data part to perform RDI.
(Radio data interface) An RDI frame encoder (18) for generating a frame, and an IEC958 sub-frame generated by using the RDI frame generated by the RDI frame encoder (18) as data and the IE thereof
It has a digital interface transmitter (19) for outputting the C958 subframe to the digital interface cable (14). The recorder (12) receives an input signal via a digital interface cable (14).
A digital interface receiver (24) for extracting an RDI frame from the EC958 subframe, an audio data extraction unit (25) for extracting audio data of a channel of a selected radio broadcast program from the RDI frame extracted by the digital interface receiver (24), and audio Data extraction unit
(25) A head for recording an audio signal relating to the data extracted
(30).

[0011] When the digital radio broadcast signal is DAB, the audio program section and the management information are each MSC.
And FIC.

The RDI frame extracted by the recorder (12) from the IEC958 sub-frame input via the digital interface cable (14) includes an audio program part of the transmission frame received and extracted by the receiver (11). And the management information, the recording device (12) can appropriately extract a predetermined radio broadcast program from the audio program unit from the management information and record it.

According to the digital radio broadcast recording system (10) of the present invention, the processor (13) is connected to the receiver (11) via the digital interface cable (14),
A predetermined radio broadcast program is selected and extracted based on the input IEC958 sub-frame, and the processing in the processor (13) is performed.

The processor (13) includes not only a recorder (13) other than the recorder (12) but also a processor other than the recorder, such as a speaker and an amplifier.

A digital signal transmitted from the receiver (11) via the digital interface cable (14) and containing a plurality of radio broadcast programs is processed by a processor (13) other than one recorder (12). 3), a desired radio broadcast program can be appropriately selected, extracted, and processed, and the processing function of the radio broadcast program in the entire digital radio broadcast recording system (10) can be enhanced.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2, the communication protocol of various elements of DAB such as a transmission frame is described. For details, see the European Telecommunications Standards Association (European Telecommunications).
communications StandardsInstiu
te) issued by the European Telecommunications Standard (European Telecommunications)
ionics Standard).

FIG. 1 shows the structure of a DAB transmission frame. Transmission frame (Transmission fra
me) is the synchronization channel, FIC (Fast)
Information Channel) and M
It has SC (Main Service Channel). The FIC further includes a plurality of FIBs (Fast
Information Block), MS
C is composed of sub-channel IDs assigned to different IDs for each of a plurality of service components (including not only radio broadcast programs but also data services) included in the transmission frame. C
IF (Common Interleaved Fra)
me) transmission unit. The DAB has specifications from mode 1 to mode 3, and the transmission frame time (duration) 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 the transmission frame is 1
Two and four.

FIG. 2 is an exemplary diagram of a DAB service structure. The ensemble (Ensemble) whose ensemble label (ensemble name) is DAB ENSEMBLE ONE has a service label of Alpha 1 Radio (ALPHA1 RADIUS).
O), a plurality of services such as beta radio (BETA RADIO) and alpha 2 radio (ALPHA2 RADIO).

[0019] The alpha 1 radio is a primary (pri
service component (Service comp)
contents, one secondary and one secondary
It has two service components of y). The primary service component is audio, and the secondary service component is a traffic message channel: T
MC (Traffic Message Channel)
l) and service information: SI (Service Info)
rmation). The voice component and SI are transmitted on separate sub-channels (SubCh) in the MSC, and the TMC
Is the FIDC (Fast Information) within the FIC
on Data Channel).

A beta radio has two service components.
Audio and secondary audio (secondary audio c
both are carried on the MSC sub-channel.

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

FIG. 3 is a block diagram of a main part of the DAB broadcast recording / playback system 10. The DAB broadcast recording / playback system 10 includes a DAB receiver 11 and usually one,
This DAB broadcast recording / reproducing system 10 is equipped with two audio recording / reproducing devices 12 and 13, and the DAB receiver 11 and the audio recording / reproducing devices 12 and 13 are connected by a digital interface cable 14 composed of an optical cable. Have been. In the DAB receiver 11, the DAB radio wave
Captured at 17. An RDI (radio data interface) frame encoder 18 generates an RDI frame from a transmission frame relating to an ensemble of a reception frequency selected by the user from radio waves captured by the antenna 17. Digital interface transmitter 19
An IEC958 subframe is generated from the RDI frame generated by the RDI frame encoder 18 and the IEC9
The 58 sub-frames are output to the digital interface cable 14.

FIG. 4 is a diagram showing the structure of the RDI frame and the IEC958 subframe and the correspondence between the RDI frame and the IEC958 subframe. The structures themselves of the RDI frame and the IEC958 subframe are well known. In the RDI frame, digits are carried up from the earliest in time, data occupies the 0th to 19th bits, and the frame type occupies the 20th to 23rd bits. The transmission mode of the RDI frame includes a high-capacity mode and a low-capacity mode. Depending on the value of the frame type, whether the RDI frame is the beginning, the continuation, the end, or the like of the data can be identified. The data includes the FIB of the DAB transmission frame (FIG. 1).
C, MSC and TII (Transmitter I
dentification Information
n) is arranged.

In the IEC958 sub-frame, the digits are carried up from the earliest in time. Preamble is occupied from the 0th bit to the 3rd bit, and Aux. Data (auxiliary data)
Data occupies the 8th to 27th bits, and 2
Bits 8, 29, 30, and 31 are V, U, C,
P.

When generating the IEC958 subframe from the RDI frame, the digital interface transmitter 19 arranges the values of the 0th to 23rd bits of the RDI frame as the values of the 4th to 27th bits of the IEC958 subframe.

In FIG. 3, the sound recording / reproducing devices 12 and 13 have the same structure.
(Mini-disc) recording / playback machine. Explaining only the audio recording / reproducing device 12, a buffer (not shown) is provided at a stage preceding the digital interface receiver 24, and a digital interface cable is provided.
The IEC958 subframe from 14 is input to the digital interface receiver 24 via the buffer and is converted into an RDI frame. Audio recording / playback device 1
Audio recording / reproducing device 12 via digital interface cable 14 interconnecting 2 and 13
Further data transfer to the playback device 13
This is performed via a buffer (not shown) at a stage preceding the digital interface receiver 24 in the digital audio receiver 12, and the same IEC958 sub-frame is input to the digital interface receivers 24 in the audio recording / reproducing apparatuses 12 and 13. ing. The RDI frame decoder 25
Extract the FIC and MSC from the RDI frame, decode the FIC first, and send it to the CPU 26. CPU 26
The sub-channel of the MSC in which the service component (= radio broadcast program) selected by the user is located is detected based on the information of the FIC, and the RDI frame decoder 25 is instructed to decode the sub-channel. The RDI frame decoder 25 decodes the sub-channel of the MSC designated by the CPU 26 and sends it to the MPEG decoder 27.
The MPEG decoder 27 returns the MPEG-compressed input data to a digital audio signal before compression. The signal processing circuit unit 28 performs code conversion of the digital audio signal input from the MPEG decoder 27 for recording on a recording medium (MD in this example), further adds an error correction code for recording, and modulates. Send to circuit 29. The modulation circuit 29 modulates the input data from the signal processing circuit unit 28 for recording on a recording medium, sends the modulated data to the recording head 30, and records the data on the recording medium via the recording head 30.

[Brief description of the drawings]

FIG. 1 is a diagram showing the structure of a DAB transmission frame.

FIG. 2 is an exemplary diagram of a DAB service structure;

FIG. 3 is a block diagram of a main part of the DAB broadcast recording / playback system.

FIG. 4 is a diagram illustrating a structure of an RDI frame and an IEC958 subframe, and a correspondence relationship between the RDI frame and the IEC958 subframe.

[Explanation of symbols]

Reference Signs List 10 DAB broadcast recording / playback system (digital broadcast recording system, digital radio broadcast recording system) 11 DAB receiver (receiver) 12 sound recording / playback device (recorder, recorder, processor) 13 sound recording / playback device Recording machine, processing machine) 14 digital interface cable 18 RDI frame encoder 19 digital interface transmitter 24 digital interface receiver 25 RDI frame decoder (audio data extraction unit) 30 recording head (head)

Claims (3)

[Claims] 1. A receiver (11) for receiving a digital broadcast signal in which a plurality of broadcast programs broadcast simultaneously are allocated to different channels in a common transmission frame and broadcast, and (b) In a digital broadcast recording system (10) having a processor (12, 13) for processing a broadcast program received by the receiver (11), the receiver (11) extracts a predetermined channel. A digital signal including a plurality of previous channels is output to a digital interface cable (14), and the processor (12,
13) is the digital interface cable (14)
A digital broadcast recording system characterized in that a predetermined broadcast program is selected and extracted from a digital signal input from the PC, and the extracted broadcast program is processed. 2. A receiver (11) for receiving a digital radio broadcast signal in which a plurality of radio broadcast programs broadcast simultaneously are allocated to different channels in a common transmission frame and broadcast. b) In a digital radio broadcast recording system (10) having a recorder (12) for recording a radio broadcast program received by the receiver (11), the receiver (11) extracts from a received signal. An RDI frame encoder (1) that generates an RDI frame using the audio program section and the management information in the transmission frame as a data section.
8), and a digital interface transmitter (19) that generates an IEC958 subframe as data using the RDI frame generated by the RDI frame encoder (18) and outputs the IEC958 subframe to a digital interface cable (14), The recorder (12) selects a digital interface receiver (24) for extracting an RDI frame from an IEC958 sub-frame input via a digital interface cable (14), or a RDI frame extracted by the digital interface receiver (24). An audio data extraction unit (25) for extracting audio data of a channel of a radio broadcast program, and a head (30) for recording an audio signal related to the data extracted by the audio data extraction unit (25). Characteristic digital radio E Broadcast recording system. 3. A processor (13) is connected to the receiver (11) via the digital interface cable (14), and selects and extracts a predetermined radio broadcast program based on the input IEC958 subframe. 2. The digital radio broadcast recording system according to claim 1, wherein the processing in the processor (13) is performed.