JP5834501B2 - Audio digital STL device and AES signal transmission method - Google Patents

Description

  The present invention relates to an audio digital STL (Studio to Transmitter Link) device, and in particular, a single carrier type audio digital STL device and an AES signal for multiplexing and transmitting information for character multiplex broadcasting to an AES (Audio Engineering Society) signal. The transmission method.

Conventionally, in an analog audio STL device, an analog audio signal is FM-modulated and transmitted. On the other hand, in the case of an audio digital STL device, after the digital audio signal is transmitted from the performance side to the transmission side, the digital audio signal is FM modulated. At this time, the digital audio signal is delivered to the FM modulator, thereby enabling delivery without damaging the main line sound source, which is an advantage of the digitized information.
In addition, in the method using the conventional audio analog STL device, the information for the transmission of the analog audio signal and the information for the text multiplex broadcasting used for the visible radio, etc., use an empty channel different from the main channel. Or using the high frequency part of the subcarrier used for stereo broadcasting. On the other hand, the audio digital STL device can transmit a digital audio signal formatted into an AES signal. Therefore, when using an audio digital STL device, it is preferable that the digitized information for teletext broadcasting can be multiplexed and transmitted on the AES signal transmitted using the main line.
For example, Patent Literature 1 discloses a technique for transmitting data (TS packet data) used for data broadcasting or the like using a transmission path for transferring video and audio. In this technique, data of TS packets is converted into data bursts, and the data bursts are mapped to audio data areas of a plurality of audio frames in an AES / EBU (European Broadcasting Union) format in a non-audio mode. This eliminates the need to separately prepare a transmission path for transmitting TS packet data.

  The AES signal uses a data format defined by a 32-bit digital audio interface format. As a technique for effectively utilizing the format of this AES audio signal, for example, the technique of Patent Document 2 is disclosed. In Patent Document 2, time information can be extracted from an AES audio signal in a unit of 32 bits or more, for example.

JP 2006-238006 A JP 2008-257059 A

However, Patent Document 1 intends to effectively use an unused area by mapping a TS packet to an unused AES / EBU area. Therefore, a process for detecting an unused area is required. Further, Patent Document 2 changes the format of an AES audio signal, and processing for converting the format is required on the transmission side. In the techniques of Patent Documents 1 and 2, a load is applied to the audio digital STL device in order to perform such processing.
SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus and a method that enable multiplexing information for text multiplex broadcasting to an AES signal by a simple means in an audio digital STL apparatus of a single carrier system.

  One aspect of the audio digital STL device according to the present invention includes an information multiplexing processing unit and a transmission processing unit. The information multiplexing processing unit receives an AES (Audio Engineering Society) signal defined in the digital audio interface format and information for character multiplex broadcasting, and multiplexes the information for character multiplex broadcasting in a spare area of the AES signal. Turn into. The transmission processing unit transmits the multiplexed AES signal.

  An aspect of the AES signal transmission method according to the present invention is an AES signal transmission method defined by a digital audio interface format in an audio digital STL device, wherein the AES signal and information for text multiplex broadcasting are transmitted. Received, multiplexes the information for text multiplex broadcasting in the spare area of the AES signal, and transmits the multiplexed AES signal.

  According to the present invention, in a single carrier type audio digital STL device, it is possible to multiplex information for text multiplex broadcasting to an AES signal by a simple means.

It is a block diagram which shows the structural example of the audio | voice digital STL apparatus which concerns on this invention. It is a block diagram which shows the detail of an information multiplexing process part. It is a figure which shows the 32-bit digital audio interface format applied to an AES signal.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. For clarity of explanation, the following description and drawings are omitted and simplified as appropriate. In the drawings, components having the same configuration or function and corresponding parts are denoted by the same reference numerals and description thereof is omitted.

  The present invention proposes a method of transmitting an AES signal and multiplexing and transmitting information for character multiplex broadcasting in the AES signal in a radio transmission system of an audio digital STL device using a single carrier digital modulation method. Hereinafter, embodiments will be described with reference to the drawings.

Embodiment 1. FIG.
FIG. 1 is a block diagram showing a configuration example of an audio digital STL device according to the present invention. As shown in FIG. 1, the audio digital STL device 1 according to the present invention includes a transmission unit 100 and a reception unit 200. The transmission unit 100 includes an AES signal processing unit 11, an information multiplexing unit 12, an error correction unit 13, a framing 14, a modulation unit 15, and a transmission conversion unit 16. The reception unit 200 includes a reception conversion unit 21, a demodulation unit 22, a deframing unit 23, an error correction unit 24, and an AES signal output unit 25. In the transmission unit 100, the AES signal processing unit 11 and the information multiplexing unit 12 may be referred to as an information multiplexing processing unit 101 that performs a process of multiplexing information for character multiplex broadcasting into an AES signal. In addition, the error correction unit 13, the framing 14, the modulation unit 15, and the transmission conversion unit 16 may be referred to as a transmission processing unit 102 that processes and transmits a multiplexed AES signal.

In the transmission unit 100, the information multiplexing processing unit 101 (the AES signal processing unit 11 and the information multiplexing unit 12) multiplexes information for character multiplex broadcasting on the AES signal.
FIG. 2 is a block diagram showing details of the information multiplexing processing unit 101. As shown in FIG. 2, the detailed configuration of the information multiplexing processing unit 101 includes an AES signal processing unit 11, a PLL (Phase-locked loop) circuit 17, and an information multiplexing unit 12.
Since the AES signal input to the audio digital STL device 1 is generated by an external device, it is input asynchronously. Therefore, the AES signal processing unit 11 regenerates an external clock from the AES signal. Then, the PLL circuit 17 generates an internal clock based on the regenerated external clock. Each component of the information multiplexing unit 12 and the transmission processing unit 102 performs processing based on the generated internal clock.
The AES signal processing unit 11 outputs the AES signal as AES data that can be processed by the information multiplexing unit 12.
The information multiplexing unit 12 outputs the AES data obtained by multiplexing the information for character multiplex broadcasting to the AES data to the error correction unit 13.

  FIG. 3 is a diagram showing a 32-bit digital audio interface format applied to the AES signal. As shown in FIG. 3, the AES signal is defined in a 32-bit digital audio interface format. Of these, information for character multiplex broadcasting is multiplexed using a part of the voice data area (the voice data area has a maximum of 20 bits) and a spare area (up to 4 bits). For example, as shown in FIG. 3, when audio data is 16 bits, information for text multiplex broadcasting can be transmitted at a maximum of 8 bits. Specifically, for example, when a 16-bit area is used as audio data, 4 bits are an empty area. Therefore, it is possible to use an 8-bit area by using the spare area 4 bits (area A1) and the empty area 4 bits (area A2).

When multiplexing information for character multiplex broadcasting into an AES signal, the information multiplexing unit 12 multiplexes the information for character multiplex broadcasting into an empty area of AES data without performing processing such as compression. If the size of the information for text multiplex broadcasting exceeds the free area of one frame, the information multiplexing unit 12 divides the information for text multiplex broadcast and multiplexes it into the free area of the next frame. .
In addition, the information multiplexing unit 12 may use the first bit of the spare area as a flag indicating whether or not information for text multiplex broadcasting is inserted in the AES signal. Or you may make it hold | maintain the flag which shows whether the information for character multiplex broadcasting is added to the header information added to a some flame | frame (unit transmitted).

By setting the flag as described above, the receiving side can grasp whether or not information for text multiplex broadcasting is multiplexed on the AES signal. For example, when the AES signal output unit 25 of the receiving unit 200 indicates that the information for character multiplex broadcasting is multiplexed, the information for character multiplex broadcasting is extracted from the AES signal and transmitted. It is possible to send the AES signal by setting the bit of the area where the information for character multiplexing is multiplexed on the AES signal to clear (default value).
Note that, among the components shown in FIG. 1, the components that are not particularly described perform the same functions as the well-known technique, and thus the description thereof is omitted.

According to this embodiment, the following advantageous effects can be achieved.
In the audio analog STL device, transmission of analog audio signals is performed. Information for teletext broadcasting used for visible radio or the like is transmitted using an empty channel different from the main channel or used for stereo broadcasting. It was transmitted using the high frequency part of the subcarrier. On the other hand, the audio digital STL device of the present embodiment transmits digital audio that is formatted into an AES signal and uses the degree of freedom of the data portion (preliminary area and audio data area) of the AES signal format. Thus, it is possible to multiplex and transmit information for text multiplex broadcasting to the data portion. As a result, the information for teletext broadcasting can be transmitted using the main line for transmitting the AES signal, so that it is not necessary to prepare a line different from the main line.

In addition, since the digital modulation system is used as non-compressed digital modulation information for the text multiplex broadcast, the audio digital STL device on the performance side does not process the received AES signal and the information for the text multiplex broadcast, The original state can be passed to the next FM modulator. Specifically, the information for character multiplex broadcasting can be transferred to the subsequent processing as it is without requiring processing such as analog / digital conversion and compression for the information for character multiplex broadcasting. As a result, it can be delivered without damaging the sound source, which is an advantage of the digitized information.
In order to achieve the advantageous effects as described above, in the audio digital STL device and the AES signal transmission method of the present embodiment, the digital audio signal is transmitted uncompressed, and for character multiplex broadcasting used for visible radio, etc. Can be provided to the receiving apparatus without using a part other than the main line or another line.

Other embodiments.
In the first embodiment, it has been described that the information for text multiplex broadcasting is multiplexed in the spare area of the AES signal and the partial area of the voice data. However, either the spare area of the AES signal or the partial area of the voice data is used. It may be a case where information for text multiplex broadcasting is multiplexed on only one of them. Also, the audio digital STL device of the present invention is not limited to using the above-described data area, but is an unused (free) area, and compresses information for text multiplex broadcasting. Other areas may be used as long as they can be multiplexed without any problem.

  In addition, this invention is not limited to embodiment shown above. Within the scope of the present invention, it is possible to change, add, or convert each element of the above-described embodiment to a content that can be easily considered by those skilled in the art.

DESCRIPTION OF SYMBOLS 1 Audio | voice digital STL apparatus 11 AES signal processing part 12 Information multiplexing part 13 Error correction part 14 Framing 15 Modulation part 16 Transmission conversion part 17 PPL circuit 21 Reception conversion part 22 Demodulation part 23 Deframing 24 Error correction part 25 AES signal output part 100 Transmission unit 101 Information multiplexing processing unit 102 Transmission processing unit 200 Reception unit

Claims (6)

Receives an AES (Audio Engineering Society) signal defined in the digital audio interface format and information for text multiplex broadcasting, and multiplexes the information for text multiplex broadcasting in the spare area of the AES signal without processing . Information multiplexing processing means,
An audio digital STL (Studio to Transmitter Link) device comprising transmission processing means for transmitting the multiplexed AES signal.   2. The audio digital STL device according to claim 1, wherein the information multiplexing processing means multiplexes the information for text multiplex broadcasting in a part of the audio data area in addition to the spare area.   The information multiplexing processing means divides the information for character multiplex broadcasting when the information for character multiplex broadcasting exceeds the free space of the frame of the AES signal, and multiplexes the information for free space of the next frame. The audio digital STL device according to claim 1 or 2.   The audio digital STL according to claim 1 or 2, wherein the information multiplexing processing means uses the head of the spare area as a flag indicating whether or not the information for text multiplex broadcasting is inserted in the AES signal. apparatus.   The information multiplexing processing means adds a flag indicating whether or not the information for character multiplex broadcasting is inserted into the AES signal to header information added to the frame of the AES signal. 2. The audio digital STL device according to 2. An AES signal transmission method defined by a digital audio interface format of an audio digital STL device,
Receiving the AES signal and information for text multiplex broadcasting;
The information for teletext broadcasting is multiplexed in the spare area of the AES signal without processing ,
An AES signal transmission method for transmitting a multiplexed AES signal.

Images