KR100606509B1 - Xtdm receiving module for audio signal routing network - Google Patents

Abstract

The present invention relates to an extended time division modulation (XTDM) receiving module for an audio signal transmission network, and more particularly, through time division modulation and coaxial cable of a plurality of channels of stereo audio signals. The present invention relates to an XTDM receiving module constituting a network that enables sharing of audio signals in multiple places separated from each other by transmission.

Audio routing system, extended time division modulation (XTDM), coaxial cable, digital audio interface

Description

XTDM RECEIVING MODULE FOR AUDIO SIGNAL ROUTING NETWORK}             

1 is a diagram showing the structure of a general audio routing system applied to a broadcasting station.

2 is a diagram illustrating a switching function processed by the router of FIG.

3 is a diagram illustrating an audio related network environment of a broadcasting station to which an audio routing system according to an exemplary embodiment of the present invention is applied.

4 is a diagram illustrating a configuration of an audio routing system applied to FIG. 3.

5A and 5B show detailed configurations and modifications of the router applied to FIG. 4, respectively.

FIG. 6 is a diagram illustrating a detailed configuration of a sound source input module illustrated in FIGS. 5A and 5B.

FIG. 7A is a diagram illustrating the AES / EBU signal transmission standard of each channel of the 64 channel sound source shown in FIG. 6, and FIG. 7B is a diagram illustrating the AES / EBU signal transmission standard shown in FIG. 7A on the assumption of a stereo environment. As shown.

FIG. 8A is a diagram showing the connection relationship and detailed configuration between the serial / parallel converter and dual port RAM shown in FIG. 6, and FIG. 8B is a diagram showing the waveform of each signal used in the circuit of FIG. 8A. 8C is a diagram for explaining a serial / parallel conversion process by the serial / parallel converter of FIG. 8A, and FIG. 8D is a diagram showing a structure of sound source data obtained by the serial / parallel conversion.

FIG. 9A illustrates a detailed configuration of the dual bank RAM illustrated in FIG. 6, and FIG. 9B illustrates a connection relationship between the multiplexer illustrated in FIG. 6 and the dual bank RAM connected to an input / output terminal thereof.

FIG. 10 is a diagram showing a detailed configuration of the XTDM transmission module shown in FIGS. 5A and 5B.

FIG. 11A is a diagram illustrating in detail a part of the audio data converter illustrated in FIG. 10, and FIG. 11B is a diagram conceptually illustrating a processing operation of the audio data extractor illustrated in FIG. 10, and FIG. A diagram showing a data format generated by the multiplexer shown in FIG.

FIG. 12 is a diagram showing a detailed configuration of the XTDM receiving module shown in FIGS. 5A and 5B.

FIG. 13A is a diagram for describing a process from an SDI deserializer to an audio data extraction unit among the XTDM receiving modules shown in FIG. 12, and FIG. 13B is a reference from the XTDM data received by the XTDM receiving module shown in FIG. 12. FIG. 13C illustrates an 8-bit / 10-bit conversion or a 10-bit / 8-bit conversion process used in the XTDM transmission and reception module. FIG.

FIG. 14 is a diagram showing a detailed configuration of the sound source output module shown in FIGS. 5A and 5B.

FIG. 15 illustrates the input / output relationship of the output channel select distributor shown in FIG. 14 in more detail.

FIG. 16 is a diagram showing a detailed configuration of the AES / EBU code generator shown in FIG. 14; FIG.

<Description of the symbols for the main parts of the drawings>

510, 520: Router 511: sound source input module

513, 523: multichannel TDM bus 515: XTDM transmission module

521: XTDM receiving module 525: sound source output module

The present invention relates to an extended time division modulation (XTDM) receiving module for an audio signal transmission network, and more particularly, through time division modulation and coaxial cable of a plurality of channels of stereo audio signals. The present invention relates to an XTDM transmission and reception module constituting a network capable of sharing audio signals in a plurality of places separated from each other through transmission, and a router and an audio routing system using the same. In particular, the present invention can be effectively used when configuring an audio signal transmission network such as a broadcasting station.

In broadcasting stations, multiple channels of audio signals recorded in a studio must be transmitted to other studios, main control rooms, or sub-control rooms. In order to share these audio sources in multiple places, each studio or control room is connected to each other. An audio signal transmission network, i.e. an audio routing system, should be provided.

According to the existing technology, in order to provide a multi-channel sound source recorded in a specific studio to each studio, the main control room where the sound source is collected is connected to each other by each studio or sub-control room and the sound source cable and the sound source selection control cable. For example, if a broadcaster has 10 studios or sub-control rooms, 20 cables are needed because the main control room that provides the sound source must provide 10 sound source cables and 10 sound source selection control cables to each studio. When a studio is opened, one source cable and one source selection control cable should be installed between the main control room and the added studio.

Hereinafter, a general audio routing system will be described with reference to FIGS. 1 and 2. FIG. 1 illustrates a structure of a general audio routing system applied to a broadcasting station, and FIG. 2 illustrates a switching function processed by the router of FIG.

As shown in FIG. 1, the audio routing system used as an audio signal transmission network of a broadcasting station is responsible for a function of receiving a plurality of sound sources and transmitting the sound sources where necessary for sharing in a plurality of studios. In FIG. 1, the arrow indicates a moving direction of the sound source, and a router located at the center plays a role of transmitting a plurality of sound sources to a plurality of studios.

The router is generally in a matrix structure, the conceptual configuration of which is shown in FIG. 2 is a configuration for explaining the operation principle of the router, the horizontal line of the matrix structure represents the sound source input, the vertical line represents the output, the point where the horizontal line and the vertical line intersect (cross point) ) Each intersection has a circular selection point, and outputs 1 through N are connected to each studio. 2 means that the sound source 1 is connected to output 1, the sound source 2 to output 2, the sound source 3 to output 3, and the sound source 4 to output 4 are respectively connected. For example, if you want to send sound source 4 to output 2, move the selection point to the intersection of sound source 4 and output 2. Studios that connect to the output port require a select point controller to select the sound source, usually with a separate data communication cable that uses serial communication.

When the conventional audio routing system described above is applied to an audio signal transmission network of a broadcasting station, a sound source providing cable and a sound source selecting cable must be separately connected to provide a sound source to each studio or control room. In particular, since the audio signal extracted from the sound source is multi-channel, the number of cables connected from the main control room to each studio or sub-control room increases rapidly with the number of channels. In addition, when an additional studio is opened, it is inconvenient to install a sound source cable and a sound source selection control cable between the main control room and the additionally opened studio. In addition, in the conventional technology, an expensive sound source cable and a sound source selection control cable are used, and equipment connected to these cables is complicated and expensive.

Meanwhile, an audio transmission network for sharing a sound source in a broadcasting station may be configured as an optical cable based system. Such optical cable-based audio transmission network has advantages in terms of transmission speed and data capacity that can be transmitted, but it is expensive equipment, and it is necessary to accurately diagnose and repair the trouble part when problems such as disconnection of optical cable line occur. The problem is that it takes a lot of money and time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described technical problems, and it is possible to share an audio signal in a plurality of places that are separated from each other through time division modulation and transmission through a coaxial cable of a multi-channel stereo audio signal using the XTDM scheme. An object of the present invention is to provide an XTDM receiving module for configuring an audio signal transmission network.

In addition, the present invention converts the multi-channel digital audio signal to the XTDM method, which is a kind of time division modulation method, converts the digital audio data according to the Serial Digital Interface (SDI) protocol, and transmits the same through a coaxial cable. It is an object of the present invention to increase the transmittable distance of an audio signal by using a coaxial cable as compared with the conventional method using a sound source cable.

In addition, the present invention simply adds a repeater and a coaxial cable to a router of an adjacent studio or control room where a sound source is already supplied, when a place requiring the sharing of a digital audio signal, that is, a sound source, is simply provided. It aims at improving the expandability in supply.

An XTDM receiving module according to an aspect of the present invention is an XTDM receiving module for converting digital audio data having an SDI signal standard transmitted through a coaxial cable into digital audio data of an AES / EBU standard and recording the same on a multichannel TDM bus.

An SDI deserializer for receiving a signal having an SDI transmission standard from the coaxial cable and separating 10-bit data and a clock signal;

A reference synchronization signal was generated using the clock signal separated by the SDI deserializer, the 10-bit data separated by the SDI deserializer was converted into 8-bit digital audio data, and the 8-bit digital audio data was stored for 64 channels. An audio data inverse converter for separating control data from a stored digital audio data format, and then reconstructing 64-channel 8-byte digital audio data by extracting only digital audio data; And

And a multi-channel TDM bus writer for time-division modulation of the 64-channel 8-byte digital audio data reconstructed by the inverse converter according to a predetermined clock frequency and recording the multi-channel TDM bus.

Hereinafter, an XTDM receiving module according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 illustrates an audio related network environment of a broadcasting station to which an audio routing system according to an exemplary embodiment of the present invention is applied.

As shown in FIG. 3, an audio-related network environment of a broadcasting station includes a plurality of sound sources for generating multi-channel digital audio data, a main control room 310, and a plurality of sub-control room 320.

Each of the main control room 310 and the plurality of sub-adjustment rooms 320 includes routers 311 and 321 for transmitting and receiving audio data, and the routers 311 and the plurality of sub-adjustment rooms of the main control room 310 are provided. Each router 321 of 320 is connected to each other by a coaxial cable following the XTDM transmission scheme. A sound source selection device 322 is connected to the router 321 of the sub-adjustment room 320, and an administrator operates the sound source selection device 322 to perform live broadcast or program editing on the digital audio data transmitted from the router 321. Can be used. In addition, the multi-channel level meter indicator 312 and the monitoring device 313 are connected to the router 311 of the main control room 310.

Each of the plurality of sound sources constitutes one audio channel and converts analog audio signals recorded in a specific studio into digital audio data. The number of channels of the entire sound source may be determined according to the capacity of the transmission network. In the present embodiment, it is assumed that 64 channel digital audio data conforming to the AES / EBU standard is used as the multi-channel sound source, but the technical scope of the present invention is not limited thereto. .

Here, the AES / EBU standard is one of the standard standards for the digital audio interface, and is based on AES / EBU3-1985, a two-channel digital interface standard proposed by the Audio Engineering Society (AES). It supports from 24 bits of resolution and sampling rate frequencies of 32 kHz, 44.1 kHz, and 48 kHz. In the embodiments of the present invention described below, it is assumed that digital audio data conforming to the AES / EBU standard has a 24-bit resolution and a sampling rate of 48 kHz, but the technical scope of the present invention is not limited thereto.

In the present invention, to transmit 64 channels of stereo digital audio data through a coaxial cable, a time division modulation (TDM: Time Division Modulation) of 64 channels of sound source, and the specification for transmitting a video signal through a coaxial cable by SMPTE The XTDM (eXtended Time Division Modulation) transmission method, which combines the technology of converting the SDI (Serial Digital Interface) standard that is suitable for audio signal transmission, is used.

The routers 311 and 321 of the main control room 310 and the sub-control room 320 convert a 64 channel AES / EBU sound source, i.e., 64 channel stereo digital audio data, into a SDI standard and convert it into an SDI standard. It also has the function of transmitting the signal from another router via coaxial cable, and converting the signal transmitted from other router to SDI standard to 64 channel digital audio data conforming to AES / EBU standard.

The multi-channel level meter indicator 312 and the monitoring device 313 may be connected to the router 311 in the main control room 310 via a coaxial cable, using the existing sound source transmission cable provided with the number of channels of the sound source. In the present embodiment, it is assumed that the connection is made through a coaxial cable.

The multi-channel level meter indicator 312 provided in the main control room 310 is a device for visually checking the level of the sound source of each channel input through the router 311. The XTDM-based coaxial cable Inverse conversion of the SDI standard is performed on the signal received from the router 311 through the conversion of the inversely converted signal into the AES / EBU standard to display the level status of the sound sources of each channel. As such, by adopting a transmission method using an XTDM-based coaxial cable, it is possible to solve the problem that as many cables as the number of channels were required to transmit a sound source of each channel. This principle and benefit is equally applicable to signal transmission between routers.

The monitoring device 313 is a device capable of monitoring the state of the 64 channel sound source input to the router 311 of the main control room 310 through the speaker, similar to the multi-channel level meter indicator 312, the Inverse conversion of the SDI standard is performed on the signal received from the router 311 through an XTDM-based coaxial cable, and the inversely converted signal is converted to the AES / EBU standard to output the sound source of each channel to the speaker.

FIG. 4 is a block diagram of the audio routing system applied to FIG. 3. As shown in FIG. 4, the audio routing system according to the embodiment of the present invention includes a plurality of XTDM routers 440, 450, and 460 installed one by one in the main coordination room or the sub coordination room. Here, the XTDM routers 440, 450, and 460 refer to routers that support the XTDM transmission scheme, which is substantially the same as the router illustrated in FIG. 3. In addition, the solid line in Figure 4 represents the connection by the coaxial cable, the dotted line represents the digital audio interface transmission of the AES / EBU standard.

Each of the XTDM routers 440, 450, and 460 basically performs time division multiplexing on 64 channels of input sources, converts them into SDI standards, and transmits them to other routers through a coaxial cable. It has the function of converting the signal into 64 channel sound source that complies with AES / EBU standard after performing inverse conversion of SDI standard. The XTDM router 450 is used in the main control room, and the sound source monitoring device 430 is connected. The XTDM repeater 460 is connected between the XTDM router 450 and the XTDM router 440, which is a kind of repeater that performs signal amplification. By using the XTDM repeater 460, when an auxiliary control room or studio is additionally opened, only the XTDM repeater can be connected to the XTDM router of the closest auxiliary control room with a coaxial cable to perform the expansion of the transmission network. In other words, in the existing audio routing system, the transmission network can be expanded more easily and inexpensively than to install a sound transmission cable between the main control room and the additional sub-control room or studio.

Next, the router used in the embodiment of the present invention will be described in more detail with reference to FIGS. 5A and 5B. 5A and 5B show detailed configurations and modifications of the router applied to FIG. 4, respectively.

5A and 5B, it can be seen that three types of routers are largely used in the embodiment of the present invention. The first type of router is a router 510 shown on the right side of FIG. 5A. The router 510 only time-division multiplexes an input source of 64 channels, converts it into an SDI standard, and transmits it to another router via a coaxial cable. It is included. The second type of router is the router 520 shown on the right side of FIG. 5A, which performs an inverse conversion of the SDI specification on a signal transmitted from another router through a coaxial cable and then conforms to the AES / EBU standard. It includes only the function of converting and outputting sound sources of 64 channels. The third type of router combines the functionality of the first and second types of routers and is shown in FIG. 5B. The router 530 illustrated in FIG. 5B has a function of time division multiplexing 64 channel input sources, converting them into an SDI standard, and transmitting them to another router through a coaxial cable, and a signal transmitted from another router through a coaxial cable. After the inverse conversion of the SDI standard, it converts the output to 64 channels of AES / EBU standard. The configuration and operation of these three types of routers will be described in more detail below.

In FIG. 5A, two routers 510 and 520 are connected to each other. The router 510 has a structure in which a sound source input module 511, a multichannel TDM bus 513, and an XTDM transmission module 515 are sequentially connected.

The sound source input module 511 receives a 64 channel sound source conforming to the AES / EBU standard, converts the sound source into an 8 byte audio data structure divided by 8 bits for each channel, and the clock frequency for processing the audio data is A clock base conversion function for adjusting a mismatch with a clock frequency of a multichannel TDM bus is performed, and the 64 channel audio data is time-division modulated by a clock of the multichannel TDM bus and transmitted to the multichannel TDM bus. The multichannel TDM bus 513 provides an interface for 64 channels of digital audio signals that are time division modulated according to the frequency of its clock. The XTDM transmission module 515 reads 64 channels of digital audio signals from the multichannel TDM bus 513, and reads the 64 signals according to the signal specifications required by the SDI transmission chip used for data transmission through a coaxial cable. The digital audio data of the channel is converted, and then the converted digital audio data is then transmitted over a coaxial cable as an XTDM audio signal according to the SDI transmission standard. As such, the XTDM audio signal transmitted through the coaxial cable reaches the counterpart router 520.

As shown in FIG. 5A, the router 520 has a structure in which the XTDM receiving module 521, the multichannel TDM bus 523, and the sound source output module 525 are sequentially connected.

The XTDM receiving module 521 receives an XTDM audio signal from another router through the coaxial cable, separates 64 channels of digital audio data included in the received XTDM audio signal, and then uses the multichannel TDM bus ( Time division modulation of the 64 channels of digital audio data according to the clock frequency of 523 is transmitted to the multi-channel TDM bus 523. As described above, the multichannel TDM bus 523 provides an interface for 64 channels of time-modulated digital audio data according to the frequency of its clock. The sound source output module 525 reads 64-channel digital audio data from the multichannel TDM bus 523 to separate digital audio data for each channel, and digital audio of each channel using a built-in AES / EBU code generator. Convert data to AES / EBU code.

The router 530 shown in FIG. 5B combines the XTDM transmission function and the XTDM reception function described above. That is, the router 530 is connected to the sound source input module 531 and the XTDM transmission module 534 to the multi-channel TDM bus 533 and the XTDM receiving module 535 to the multi-channel TDM bus 533. The sound source output module 532 has a connected structure. The function of each component of the router 530 is the same as described above with reference to FIG. 5A.

On the other hand, the router 530 shown in Figure 5b is connected to a repeater (540) to operate as a kind of signal repeater to the XTDM receiving module 535, the repeater 540 is the XTDM reception of the router 530 The module 535 receives the XTDM audio signal received, amplifies the signal level, and transmits the signal to another router. By using such a repeater 540, when a studio or sub-control room of a broadcasting station is additionally opened, router expansion can be easily performed by connecting the repeater and the router of an adjacent control room.

Hereinafter, each component of the router illustrated in FIGS. 5A and 5B will be described in detail with reference to the accompanying drawings.

6 illustrates a detailed configuration of the sound source input module illustrated in FIGS. 5A and 5B. FIG. 7A shows a signal transmission standard of each channel of the 64 channel sound source shown in FIG. 6, and FIG. 7B shows a diagram assuming a stereo environment for the signal transmission standard shown in FIG. 7A.

More specifically, in FIG. 6, eight sound source input modules 610, 620, 630, and 640 (only four are shown in the figure for convenience of description) for processing a 64 channel AES / EBU sound source are multichannel TDM buses 650. Although a configuration connected to the drawing is illustrated in the present invention, one sound source input module is designed to process 8 channels of AES / EBU sound sources, but the technical scope of the present invention is not limited thereto.

The eight-channel sound source input module 610 receives eight output signals from each receiver 611 and eight receivers 611 for receiving eight channels of AES / EBU sound sources, respectively, and converts a sampling rate. And a sample rate converter 612, an audio signal collector 613, a multichannel TDM bus selector 614, and a geomatrix addressing device 615. The internal configuration of the remaining sound source input modules 620, 630, and 640 is the same as that of the sound source input module 610.

The 64-channel AES / EBU sound sources input to the respective sound source input modules are A / D-converted digital audio data recorded in a studio or the like, and follow the AES / EBU standard, which is a digital audio transmission standard. FIG. 7A illustrates such an AES / EBU signal transmission standard, and FIG. 7B illustrates a diagram of the AES / EBU signal transmission standard assuming a stereo environment.

Referring to FIG. 7A, one subframe includes 32 bits, and more specifically, includes 4 bits of preamble, 4 bits of auxiliary data, and 20 bits of audio data. And a validity bit (V), user data bits (U), channel state data bits (C), and parity bits (P), each of which is one bit.

The subframe of FIG. 7A uses a mono sound source, and since a stereo broadcast is required in a general broadcasting environment, 64 bits are required. The 64 bits in which the 64 bits are grouped by 8 bits is shown in a table of FIG. 7B. In Fig. 7B, 4-bit auxiliary data, 8-bit audio data LSB, 8-bit audio data MSB, and 4-bit audio data MSB constitute 24-bit audio data. The 4-bit additional data is data required in the process of transmitting audio data of AES / EBU standard. In the XTDM transmission environment according to the present invention, the 64-bit AES / EBU standard audio data is converted into a data structure composed of 8 bytes. This will be explained in more detail later.

Referring to FIG. 6 again, eight AES / EBU receivers 6111 to 6118 allocated to each AES / EBU sound source of each channel receive digital audio data of AES / EBU standard and convert it into I2S format, a serial data transmission standard. To output the digital audio data.

Each of the AES / EBU receivers 6111 to 6118 outputs the digital audio data converted into the I2S format to a corresponding one of the eight sample rate converters 6121 to 6328, respectively. 6128 converts the sample rate of the digital audio data to 48 kHz set in the XTDM environment, and outputs the same to the audio signal collector 613.

The audio signal collecting unit 613 converts digital audio data of an I2S format into a data format for transmission to the multichannel TDM bus. That is, the audio signal collecting unit 613 converts serial digital audio data in I2S format into a parallel type, and generates left and right digital audio data for stereo by generating a data structure in which 8 bytes separated by 8 bits constitute one frame. Get In addition, the audio signal collector 613 may be one-chip into a field programmable gate array (FPGA), which is a kind of application-specific semiconductor, and thus, the size of the entire module may be reduced by one-chip, thereby making the router compact.

As described above, by using a data structure that constitutes one frame with eight bytes divided by eight bits, data is moved in units of eight bits, so that a logic circuit is easily configured. In addition, since commercially available logic circuit components are composed of basic 4 bits or 8 bits, they can be easily applied when additional components are needed outside of the audio signal collector 613 composed of FPGAs. Easily adapted to bit audio or 24-bit audio environments.

8A shows a connection relationship between the serial / parallel converter 6131 and the dual port RAM 6133 of the audio signal collector 613 and its detailed configuration. Each of the blocks 6131-1, 6131-3, and 6131-4 and the dual port RAM 6133 of the serial / parallel converter 6131 is synchronized with the clock signal SCK (3.072 MHz). It is operated by a single clock signal. The period of the input FSYNC signal is configured as 1 / (48 kHz), and the clock of the SCK signal is generated 64 times during one period of the FSYNC signal. The flip-flop 6131-1, into which the FSYNC signal is input, is a kind of latch and produces a signal FLAG having the same waveform as the FSYNC signal slower by one clock of the SCLK than the FSYNC signal. generates a FLAG signal at each kHz period. 8b shows the waveform of each signal used in the circuit of FIG. 8a. Referring to FIG. 8B, it can be seen that the same waveform as the FSYNC signal is delayed by one clock of the SCLK signal. The flip-flop 6131-2 generates a reset signal by using a comparator logic that determines the FLAG signal generated by the flip-flop 611-1-1 and the [FSYNC = 0, FLAG = 1] therein. The Reset signal controls the operation of the 6-bit counter 6131-3 performing incremental counting by the clock of the SCLK signal, and as shown in FIG. 8B, the 6-bit counter 6131-3 ultimately FSYNC. The signal is synchronized to output a constant 6-bit count value.

The upper 3 bits of the count value of the 6-bit counter 6131-3 are used as an address of the dual port RAM 6133. In addition, the 8-bit shift register 6131-4 sequentially receives the digital audio data of the serial type of the I2S standard from the corresponding sample rate converter 6121, shifts the data of the 8-bit capacity, and then converts the 8-bit capacity. Data is outputted to the dual port RAM 6133. Accordingly, the dual port RAM 6133 stores digital audio data output in 8-bit units of the 8-bit shift register 6131-4 using the count value from the 6-bit counter 6133-3 as an address. Can be. FIG. 8C conceptually illustrates a process of separating digital audio data of serial type in I2S format by 8-bit units by shift registers by 8 bits. As described above, the address is a value extracted from the upper 3 bits of the 6-bit counter 6131-3. In this way, one frame of audio data stored in the dual port RAM 6133 has a data structure as shown in FIG. 8D, and eight bytes divided by eight bits constitute one frame, and left and right audio for stereo implementation. It can be seen that the sound source data is provided.

Meanwhile, in the exemplary embodiment of the present invention, RAM is used to reduce the amount of flip-flop segments of the audio signal collector 613 implemented by the FPGA. The audio signal collector 613 requires many flip-flop segments to process stereo digital audio data, and when all of them are implemented as FPGAs as flip-flops, the FPGA becomes complicated and the unit cost of the FPGA increases greatly. In particular, in the embodiment of the present invention, dual port RAM capable of simultaneously reading and writing by a single clock is used.

In this dual port RAM, if the synchronization between the write clock and the read clock of the input and output sides is not correct, a write operation occurs during a read operation, which causes transmission of digital audio data. Some bits may be lost in the process. In order to reduce such bit loss, a dual bank method using two dual port RAMs is used. The dual bank method consists of two dual port RAMs, and a detailed configuration of the dual bank RAM used in the embodiment of the present invention is shown in FIG. 9A.

9A, dual bank RAM 6133 consists of two dual port RAM banks 1 and 2 (6133-5, 6133-6), and these dual port RAM banks 1 and 2 (6133-5, 6133-). A counter 6133-4 for providing an address to 6), flip-flops 6133-1 and 6133-2 for generating a reset signal to be provided to the counter 6133-4 using the FSYNC signal, and A flip-flop 6133-3 is further included to generate enable signals Q1 and Q2 to be provided to the dual bank RAM banks 1 and 2 633-6 and 6133-6 by using a FSYNC signal.

The FSYNC signal is a reference sample frequency of digital audio data, and the WCLK, which is a write clock, is determined according to the capacity of RAM to be implemented, and the data signal DATA is input at once in 8-bit units. Data. The flip-flop 6133-3 uses an FSYNC signal as a D-type to generate enable signals Q1 and Q2 for determining whether to enable or disable each dual port RAM bank, and the enable signals Q1 and Q2 are The clock signal is 24 kHz divided by 48 kHz, which is a basic sample rate of digital audio data. Since the enable signals Q1 and Q2 have different phases, the input digital audio data is input to two dual port RAM banks 6331. -5, 6133-6) alternately write.

The frequency of the write clock WCLK is determined by (number of channels x 8 bytes x 48 kHz). When the number of channels is 8 by the dual port RAM, the frequency of the WCLK signal is 3.072 MHz. That is, the WCLK signal determines the frequency corresponding to the number of channels of digital audio data to be stored in the dual port RAM bank, and the RCLK determines the frequency corresponding to the number of channels of digital audio data to be read from the dual port RAM bank. The digital audio data can be safely transported even in an environment using an operating clock. FIG. 9B illustrates a detail of the multiplexer 6135 of the audio signal collector 613 to which the dual bank RAM as described above is applied to the input / output side, respectively.

Referring to FIG. 9B, dual bank RAMs 6133 and 6134 respectively store four channels of digital audio data are connected to an input side of a multiplexer 6133 made of a data selector, and eight channels are connected to an output side of the multiplexer 6133. Dual bank RAM 6136 for storing digital audio data is connected. The dual bank RAMs 6133 and 6134 respectively store four channels, that is, 32 bytes of digital audio data, and the dual bank RAMs 6136 stores eight channels, that is, 64 bytes of digital audio data. In FIG. 9B, the main clock uses a clock frequency of 24.576 MHz (64 ch × 8 bytes × 48 kHz) to transfer 64 channels of digital audio data to the multichannel TDM bus 650. Main Clock / 8 uses a clock frequency of 3.072 MHz to process eight channels of digital audio data, and Main Clock / 16 uses a clock frequency of 1.536 MHz to process four channels of digital audio data.

Two dual bank RAMs 6133 and 6134 located on the input side of the multiplexer 6133 respectively store four channels of digital audio data in synchronization with the clock frequency of the CLK / 16, and the multiplexer 6133 stores the CLK / 8. The digital audio data stored in the dual bank RAMs 6133 and 6134 are read in synchronization with a clock frequency. Through this process, four channels of digital audio data are read twice during one period of the 48 kHz FSYNC signal. More specifically, the multiplexer 6133 reads data from the dual bank RAM 6133 located at the upper half of the clock frequency of the FSYNC signal of 48 kHz through the data selector therein, and the clock frequency of the FSYNC signal. During the next half cycle, data is read from the dual bank RAM 6132 located below, and the read data are synthesized and output to the dual bank RAM 6136. Accordingly, eight channels of digital audio data are stored in the dual bank RAM 6136 in synchronization with a clock frequency of CLK / 8.

As shown in FIG. 6, the dual bank RAM 6136 interfaces with the multi-channel TDM bus 650 through the multi-channel TDM bus selector 614, so that the 48 kHz FSYNC signal is synchronized with the frequency of the CLK signal. Repeats 8 times during 1 clock cycle of. The multichannel TDM bus selector 614 of FIG. 6 selects and transmits 8 channels of digital audio data according to the address information provided from the geomatrix addressing device 615 to the multichannel TDM bus 650.

Meanwhile, the eight eight-channel sound source input modules shown in FIG. 6 each have unique geomatrix addresses, and each module is sequentially selected by a geomatrix addressing device provided therein to provide eight-channel digital audio data. By being transmitted to the multichannel TDM bus 650, all 64 channels of sound sources may be transmitted to the multichannel TDM bus 650. As described above, the 64 channel digital audio data carried on the multichannel TDM bus 650 is transmitted to the coaxial cable by the XTDM transmission module, which will be described later, and thus can be transmitted to other routers connected to the coaxial cable. Hereinafter, an XTDM transmission module will be described in detail with reference to FIG. 10.

As shown in FIG. 10, the XTDM transmission module 710 includes a multi-channel TDM bus loader 711, an audio data converter 712, an SDI serializer 713, and an SDI distributor. 714, and further includes a PLL comparator 715 and a voltage controlled oscillator 716 to generate a clock required for the system by receiving an AES / EBU Sync reference from the outside.

In addition, the audio data converter 712 includes a 384 byte dual bank RAM 7122, a 100 byte dual port RAM 7123, an SDI interface character generator 7224, a blank character generator 7125, and a multiplexer 7926. A dual bank RAM 7227, an 8-bit / 10-bit converter 7282, and a system operating clock separator 7129. Here, the audio data converter 712 may be one-chip into a Field Programmable Gate Array (FPGA), which is a kind of an on-demand semiconductor, and thus, the size of the entire module may be reduced by one-chip, thereby making the router compact.

Basically, the XTDM transmission module 710 transmits 64 channel digital audio data loaded on the multichannel TDM bus 650 to the multichannel TDM bus loader 711 by the AES / EBU sound source input module shown in FIG. 6. After reading the data, the 64-channel digital audio data read by the audio data converter 712 is converted into the SDI signal transmission standard for coaxial cable transmission, and the SDI serializer 713 converts the SDI signal standard. 64 channel digital audio data is transferred to another router via coaxial cable.

FIG. 11A illustrates the audio data converter 712 of FIG. 10 in more detail. The multichannel TDM bus loader 711 of FIG. 10 reads 64 channel digital audio data loaded on the multichannel TDM bus 650 and transmits the 64 channel digital audio data to the audio data converter 712.

The audio data extracting unit 7121 of the audio data converting unit 712 performs a function of converting 8-byte digital audio data into 6-byte data. As described above, the basic unit of the digital audio data used in the XTDM environment of the present invention is composed of 64 bits by adding the left data (32 bits) and the right data (32 bits), but in broadcast equipment, 24 bits as digital audio data. In this case, unused intervals of 1 byte each occur in the left data and the right data. Accordingly, the audio data extracting unit 7121 extracts only 6 bytes constituting the actual audio data from one channel of audio data input in 8 bytes. By doing so, the space occupied by the remaining two bytes can be used for control data transmission in SDI transmission.

FIG. 11B illustrates a process of extracting only 6 bytes constituting actual audio data from audio data input by 8 bytes by the audio data extraction unit 7121. Referring to FIG. 11B, it can be seen that unused 1 bytes of left and right are removed from stereo 8 bytes of digital audio data. 64 channels of digital audio data composed of 6 bytes per channel extracted by the audio data extraction unit 7121 are 384 bytes (6 bytes x 64 channels), and are stored in the dual bank RAM 7122-4 of FIG. 11A.

Referring to FIG. 11A, the multiplexer 7226 receives data from the dual bank RAMs 7122 and 7123, the SDI interface character generator 7224, and the blank character generator 7125, and is synchronized with the FSYNC signal. The format of data to be transmitted through the SDI serializer 713 is configured by referring to the address value of the generated counter 7122-3. The data specification required for SDI transmission is shown in FIG. 11C.

In an embodiment of the present invention, a serializer dedicated to coaxial cable transmission is used to transmit digital audio data to a coaxial cable, and XTDM uses SDI (Serial Digital Video Interface) recommended by the SMPTE 259M standard. The SDI is a technology originally implemented to transmit digital video data. The SDI has a space capable of inserting 16 channels of digital audio data, but the 16 channels are considerably less than those used in a broadcasting environment in which an audio-oriented digital audio environment is established. Because of the amount, there are many wasteful factors in applying the SDI protocol specified by SMPTE 259M to the present invention. Accordingly, in the XTDM environment of the present invention, a new multichannel audio transmission protocol is introduced by applying the SDI protocol to insert 64 channels of digital audio data into the SDI standard. In addition, it is possible to improve the transmission environment of the audio routing system by setting a section remaining even after transmitting 64 channels of digital audio data as a section capable of transmitting additional control data.

Without using the protocol recommended by SMPTE 259M, SDI environments cannot guarantee the stability of signals transmitted over coaxial cables. However, when the SDI-only protocol is used, 64 channels of digital audio signals cannot be transmitted through a coaxial cable, so the XTDM of the present invention adopts the SDI protocol of 512 bytes as shown in FIG. 11C.

In FIG. 11C, SAV (Start of Active Video) and EAV (End of Active Video) are four-byte code files indicating the start and end points of the SDI transmission protocol described in SMPTE 259M, which defines the SDI interface specification. . The audio data is a 384 byte digital audio data section consisting of 64 channels of digital audio data. The control data is a section of 100 bytes into which control data can be put in addition to digital audio data in the XTDM transmission section. The blank is data that helps the SDI deserializer of the XTDM receiving module receiving the data through the coaxial cable to find the correct position of the SAV and the EAV. The blank has a value of 2A8h in a 20-byte period. The reason for such blank insertion is to reduce the energy loss in the coaxial cable caused by inserting consecutive 00h values due to the function of the NRZ-NRZI embedded in the SDI transmission chip used in the XTDM transmission process. will be. That is, even if the NRZ-NRZI function is performed by converting the 00h value to another value of 2A8h, the XTDM receiving module is provided by removing the continuous 00h value to maintain a constant power value on the coaxial cable transmission line in the XTDM environment. SDI deserializers help to reliably recognize SAVs and EAVs to identify a section of data.

As described above, the multiplexer 7226 receives data from the dual bank RAMs 7122 and 7123, the SDI interface character generator 7224, and the blank character generator 7125, and synthesizes each input data. The SDI serializer 713 can configure a format of 512 bytes of data for SDI transmission. The data synthesized by the multiplexer 7226 may be stored in the 512-byte dual bank RAM 7227 and input to the 8-bit / 10-bit converter 7282.

The number of bits of data required for the SDI transmission is 10 bits. In general, 8-bit data transmission is common, but the reason for applying 10-bit transmission is to maintain a constant power distribution in the signal line on the cable by uniformly distributing power distribution during the transmission process. It functions to keep the power consumption of transmission equipment constant and can be configured to minimize the instability of data reaching the receiving equipment to perform 10-bit data transmission. Although SMPTE 259M recommends using 8-bit / 10-bit conversion, loss occurs when the receiver restores the linear components of digital audio data converted from analog audio signals with frequency bands from 20 Hz to 20 kHz. This is difficult to apply. For this reason, the 8-bit / 10-bit converter 7282 according to the embodiment of the present invention converts 8-bit data into 10-bit data by an XOR (eXclusive OR) operation as shown in Table 1 below. When 00h value is converted, it is converted to 2A8h value.

Bit number Transformation Expression 9th (Bit 7 of Data) XOR 1b 8th (Bit 6 of Data) XOR 0b 7th (Bit 5 of Data) XOR 1b 6th (Bit 4 of Data) XOR 0b 5 times (Bit 3 of Data) XOR 1b 4 times (Bit 2 of Data) XOR 0b number 3 (Bit 1 of Data) XOR 1b No.2 (Bit 0 of Data) XOR 0b number 1 0b (fixed) 0 0b (fixed)

As described above, the 10-bit converted audio data is transmitted to the SDI serializer 713, and the SDI serializer 713 transmits the converted 10-bit audio data through a coaxial cable according to the SDI signal transmission standard. In this case, at least one coaxial cable (four coaxial cables in this embodiment) may include an SDI distributor 714 as shown in FIG. 10 capable of transmitting digital audio data of the SDI signal standard. That is, the SDI distributor 714 allows up to four XTDM receiving modules to be wired through a coaxial cable.

On the other hand, the XTDM transmission module 710 is provided with a phase locked loop (PLL) means for synchronizing the reference clock in the operation of the XTDM equipment at the same clock frequency as the external equipment. The AES / EBU Sync reference supplied external to the XTDM transmission module 710 is synchronized to a 48 kHz FSYNC signal at the system operating clock separator 7129 via a PLL comparator 715 and a voltage controlled oscillator 716. Various clock signals are generated as shown in the figure, and these clock signals are supplied to all modules inside the XTDM device.

Clock signal frequency Frame Sync x 1 48 kHz Frame Sync x 2 96 kHz Frame Sync x 4 192 kHz Frame Sync x 8 384 kHz Frame Sync x 16 768 kHz Frame Sync x 32 1536 kHz Frame Sync x 64 3072 kHz Frame Sync x 128 6144 kHz Frame Sync x 256 12288 kHz Frame Sync x 512 24576 kHz

Next, the digital audio data transmitted through the coaxial cable is transferred to another router and received by the XTDM receiving module of the router. 12 shows a detailed configuration of such an XTDM receiving module 720.

Referring to FIG. 12, the XTDM receiving module 720 includes an SDI equalizer 721, an SDI deserializer 722, an audio data inverse converter 723, a PLL comparator 724, and a voltage controlled oscillator. 725 and a multichannel TDM bus writer 726.

In addition, the audio data inverse converter 723 may include a 10-bit / 8-bit converter 7121, a reference signal detector 7222, a system operation clock separator 7103, a 512-byte dual bank RAM 7204, a demultiplexer 7235, A 100-byte dual port RAM bank 7236, an audio data extractor 7237, and a 512-byte dual bank RAM 7238 are included. 13A shows a more detailed configuration of the audio data inverse transform unit 723. In this case, the audio data inverse converter 723 may be one-chip into a field programmable gate array (FPGA), which is a kind of application-specific semiconductor. In this way, the size of the entire module may be reduced, thereby making the router compact.

The SDI equalizer 721 performs an equalizing function for amplifying a predetermined level of the signal transmitted from the coaxial cable and outputs the equalized function to the SDI deserializer 722. At this time, the output signal of the SDI equalizer 721 is a kind of repeater and outputs to a repeater provided on the outside of the XTDM module 723 so that the signal received through the coaxial cable is transmitted to another router.

The SDI deserializer 721 generates 10-bit data and a clock signal of 24.576 MHz from the input signal. The reference signal detector 7222, the PLL comparator 724, the voltage controlled oscillator 725, and the system operating clock separator 7233 perform a reference clock extraction function, more specifically, received by the SDI deserializer 721. Analyze 10-bit data and clock signal to extract FSYNC signal of 48 kHz, AES / EBU synchronization reference frequency, and provide to XTDM receiving module 720 and AES / EBU sound source output module to be described later to synchronize with external equipment. Can be used to match FIG. 13B is a diagram for explaining a process of extracting the FSYNC signal which is the reference synchronization signal.

As shown in FIG. 13B, the reference signal detector 7222 of the inverse audio data converter 723 finds the SAV value of 4 bytes, and if there is no abnormality until the last fourth SAV value, the FSYNC value is high to low. Move to (low), find 4 byte EAV value and move FSYNC value from low to high if there is no problem until last 4 EAV value. Repeatedly repeating this process yields a clock of 48 kHz, which is then processed by the PLL comparator 724 and subsequent circuits to provide an operating clock used within the XTDM receiving module and the AES / EBU sound source output module. Can be used as a reference sync signal. This process is different from general data communication in which an acknowledgment process is performed using an ACK or NAK signal indicating that a signal is normally received. Because of the streaming method, it is necessary to create a stable path environment from the transmission process to the reception process. Considering these problems, the 64-bit digital audio data is transmitted without loss by forcibly inserting the 20-byte blank signal into the 8-bit / 10-bit conversion function and the SDI signal specification described above.

FIG. 13C is a diagram illustrating an 8-bit / 10-bit conversion or a 10-bit / 8-bit conversion process. In other words, a process of converting 8-bit digital audio data into a 10-bit SDI signal standard or converting data of a 10-bit SDI signal standard into 8-bit digital audio data is illustrated, and an XOR operation with 1010101000b (2A8h) in both directions is shown. To do.

The SDI transmit / receive chip specified by SMPTE 259M is equipped with the NRZ-NRZI function to prevent the polarity of the signal from being changed in the coaxial cable which is an unbalanced cable. This feature also has the effect of keeping the transmission energy of the coaxial cable constant when transmitting digital video signals. However, when a continuous zero value of digital audio data converted from an analog audio signal having continuity to a digital signal is applied to the NRZ-NRZI, as shown in the digital video transmission process, a constant transmission energy is applied to a coaxial cable. I can't keep it. For this reason, 8-bit / 10-bit converters and 10-bit / 8-bit converters are inserted into the connection portions connected to the SDI serializer or SDI deserializer, respectively, so that the coaxial cable transmission energy density is kept constant during XTDM transmission. Audio data can be transmitted over long distances.

In FIG. 13A, the data converted into 8 bits by the 10-bit / 8-bit converter 7141 is stored in the dual bank RAM 7204 and then provided to the demultiplexer 7235. The demultiplexer 7235 includes a counter and a data separator therein, and separates data input from the dual bank RAM 7204 into digital audio data and control data based on an address provided from the counter. The separated digital audio data is provided to an audio data extraction unit 7237, and the control data is provided as external output data through the control data output unit 7235-1.

The control data provided as external output data through the data output unit 7235-1 is responsible for providing additional data to a receiving router device in a router device that collects and transmits a sound source. For example, additional information about the sound source collected by the transmitting side router equipment may be collected and provided to the receiving side router equipment using the control data section. Such control data information is that the sound data cable and the control cable are separately configured in the existing router equipment, so that the control data is inserted into the sound source cable, thereby providing an advantage of not having to add a separate control data cable.

On the other hand, the audio data extractor 7237 reconstructs 64 channel audio data into 8-byte digital audio data and stores it in a 512-byte dual bank RAM 7238, and the multi-channel TDM bus writer 726 stores the dual bank RAM. Digital audio data stored in 7238 is recorded on the multichannel TDM bus 650. The frame sync clock is responsible for grouping all devices having digital audio input / output operating as individual devices in a digital audio environment into a single clock. In the XTDM environment, the 48kHz frequency currently specified by broadcasters as the standard is used as the frame sync clock. The master clock is the basic operating clock for the router equipment responsible for XTDM input and output. It uses 24.576MHz clock, which is 512 times 48kHz.

As such, the data recorded on the multichannel TDM bus 650 may be provided to other modules connected to the bus, in particular AES / EBU sound source output modules, as digital audio data received via a coaxial cable.

Next, the AES / EBU sound source output module will be described with reference to FIGS. 14 to 16.

Referring to FIG. 14, 64 channels of digital audio data are time-division modulated by a clock frequency of 24.576 MHz, and eight eight-channel AES / EBU sound source output modules 810, 820, 830 and 840 (only four are shown for convenience of description) perform a function of converting 8-channel digital audio data from the multi-channel TDM bus 650 into 8-channel AES / EBU audio data, respectively. . Since each of the eight channel AES / EBU sound source output modules 810, 820, 830, and 840 has the same configuration and performs the same operation, only one of them will be described.

The eight-channel AES / EBU sound source output module 810 includes a multichannel TDM bus loader 811, a geomatrix addressing device 812, an audio signal converter 813, and eight AES / EBU drivers 814. It includes. In addition, the audio signal converter 813 includes a 64 byte dual bank RAM 8131, an AES / EBU channel state block generator 8132, an output channel select distributor 8133, an 8 byte dual bank RAM 8132, and eight AES / EBU code generator 8133 is included.

When the address of the eight-channel digital audio data stored on the multichannel TDM bus 650 is selected by the geomatrix addressing device 812, the digital audio data is stored in the multichannel TDM bus loader 811. It is read through and stored in the 64 byte dual bank RAM 8121 of the audio signal converter 813. The dual bank RAM 8121 is responsible for storing digital audio data of eight channels.

Next, the output channel select divider 8333 divides the eight channels of digital audio data stored in the dual bank RAM 8131 into eight single channels. Read audio data. A detailed configuration of the output channel select distributor 8133 is shown in FIG.

The eight single digital audio data reads are stored in dual bank RAMs (8134), each individually assigned, using a 3.072 MHz frequency clock, and an AES / EBU code generator using a 384 kHz frequency clock. (8135).

Referring to FIG. 15, the output channel selection divider 8133 illustrates a method of separating eight channels of digital audio data into eight single channels, and the frequency of each clock is as follows.

CLK clock = 24.576 MHz = 64 channels * 8 bytes * 48 kHz

CLK / 8 clock = 3.072 MHz = 8 channels * 8 bytes * 48 kHz

CLK / 16 clock = 384 kHz = 1 channel * 8 bytes * 48 kHz

The counter 8333-3 built in the output channel select divider 8133 provides an address value to the channel selector 8133-4 that separates 8 channels of digital audio data according to the period of the FSYNC 48 kHz reference synchronization clock. .

The AES / EBU code generator 8235 shown in detail in FIG. 16 is an AES / EBU transmission dedicated chip already commercialized. Since the AES / EBU transmission chip is already followed, the AES / EBU transmission chip provides a simple and fast development environment.However, many XTDM transceivers have a large number of output channels that must be individually applied to a single channel. Quantity demands, and this environment results in higher equipment prices. In addition, when the AES / EBU transmission chip is discontinued, if it is reviewed and applied to another company's transmission chip, the AES / EBU transmission chip interface environment must be changed, thus performing the same function but having different conditions. / EBU sound source output module, so double the burden.

In order to compensate for this disadvantage, the audio signal converter 813 includes an AES / EBU code generator 8235 to simplify the configuration of the AES / EBU sound source output module. For example, in order to output 64 channels of digital audio data, when using commercially available AES / EBU transfer chips, 64 transfer chips and 8 FPGA chips (FPGA chips implementing AES / EBU sound source output modules) are required. . However, including the AES / EBU code generator as above eliminates the need for 64 transport chips.

In Fig. 16, the basic inputs are a data port of dual bank RAM 8342-1 which accepts digital audio data, FSYNC, which is a 48 kHz synchronous frequency clock, and a CLK clock used as an operating clock. The AES / EBU transmission data code of the format as shown in FIG. 7A may be reproduced using the above FPGA program logic.

The FRAME0 port in FIG. 16 is responsible for determining the starting point for reproducing the AES / EBU code. The 192-bit special data structure specified by the AES / EBU association is reproduced by the step 192 of the steps reproduced by the frame counters 8235-3 and 8135-9, and the stcnt counter value generated by the counter 8235-10 is reproduced. By doing so, it is possible to determine a basic order of 192 subframes and a configuration order of 24-bit digital audio data. The multiplexer 8135-15 receives the stcnt value and reorders it in the order of preamble, audio data, and special data (V, U, C, P) in AES / EBU format.

The broadcast digital audio transmission line standard specified by the AES / EBU Association is defined in the balanced RS-485 unidirectional format. The AES / EBU driver 814 shown in FIG. 14 is a commercially available product, and serves as an interface for converting AES / EBU code data generated by the AES / EBU code generator into a balanced type and providing the same to the transmission line.

The XTDM receiving module according to the present invention enables the multi-channel digital audio signal to be shared in a plurality of places separated from each other by time-division modulation and transmission through a coaxial cable of the multi-channel stereo audio signal by the XTDM method. It converts audio signal to XTDM method which is a kind of time division modulation method, converts digital audio data according to Serial Digital Interface (SDI) protocol and transmits it by coaxial cable, and uses sound source cable by using coaxial cable as transmission medium. Compared to the conventional method, the transmittable distance of the audio signal can be increased, and when a digital audio signal, that is, a place requiring sharing of the sound source is added, the repeater and the router of the adjacent studio or control room where the sound source is already supplied are added. Simply by installing a coaxial cable By ball it can increase the scalability of the additional supply source.

What has been described above is only one embodiment for implementing the XTDM receiving module according to the present invention, and the present invention is not limited to the above-described embodiment, and the scope of the present invention as claimed in the following claims Without this, anyone skilled in the art to which the invention pertains will have the technical spirit of the present invention to the extent that various modifications can be made.

Claims (6)

XTDM receiving module converts digital audio data having SDI (Serial Digital Interface) signal standard transmitted through coaxial cable into AES / EBU standard digital audio data and writes it to multi-channel TDM (Time Division Modulation) bus. , An SDI deserializer for receiving a signal having an SDI transmission standard from the coaxial cable and separating 10-bit data and a clock signal; A reference synchronization signal was generated using the clock signal separated by the SDI deserializer, the 10-bit data separated by the SDI deserializer was converted into 8-bit digital audio data, and the 8-bit digital audio data was stored for 64 channels. An audio data inverse converter for separating control data from a stored digital audio data format, and then reconstructing 64-channel 8-byte digital audio data by extracting only digital audio data; And And a multi-channel TDM bus writer for time-division modulation of the 64-channel 8-byte digital audio data reconstructed by the inverse transform unit according to a predetermined clock frequency and writing the multi-channel TDM bus writer. The method of claim 1, wherein the inverse audio data conversion unit, A reference signal detector for searching a code file included in the separated data in the SDI deserializer to check an abnormality between adjacent code files and changing a signal level according to the result to generate a synchronous reference clock signal for processing digital audio data ; A 10-bit / 8-bit converter for converting the 10-bit data separated by the SDI deserializer into 8-bit data by performing an exclusive OR operation on a bit-by-bit basis; A first dual bank RAM for storing the data converted into the 8-bit data by 64 channels; A demultiplexer for separating and outputting control data from 64-channel digital audio data stored in the first dual bank RAM; An audio data extraction unit for reconstructing 8-byte digital audio data from 64-channel digital audio data from which control data is separated in the demultiplexer; And And a second dual bank RAM configured to store 64-channel 8-byte digital audio data reconstructed by the audio data extractor. The XTDM receiving module of claim 2, wherein the audio data inverse transform unit is one-chip into a field programmable gate array (FPGA). The XTDM receiving module according to claim 2, wherein the synchronization reference clock signal is a frame synchronization signal (FSYNC) of 48 kHz. 2. The XTDM receiving module of claim 1, further comprising an SDI equalizer that amplifies the signal level transmitted between the coaxial cable and the SDI deserializer to compensate for losses during transmission over the coaxial cable. The XTDM receiving module of claim 5, wherein the signal output from the SDI equalizer is provided to the SDI deserializer and transmitted to another router through a repeater located outside the XTDM.

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