KR0147325B1 - Multiplexing in the satellite telecom - Google Patents

Abstract

The present invention relates to a multiplexing device for signaling data transmission in a DGS-200 satellite communication system. In particular, since the satellite communication is set to a voice mode and only when voice is detected by a voice activation detector during operation, the reception is performed at the receiving side. Background noise must be generated and inserted between the received bursts, in order to transmit the required BACK-GROUND NOISE LEVEL of the sender's voice channel through the traffic channel with the voice burst, or to provide data desired by the user. It is not provided in the conventional satellite communication system operated in a manner of allocating a single carrier to a single channel in a required allocation method of the carrier allocation of the satellite in order to transmit independently at low speed without disturbing the ongoing communication, Independently transmitted audio data or continuous digital data Of an implementation of a signaling multiplexer device (MUX) for transferring data.

Description

Multiplexing Device for Signaling Data Transmission in Satellite Communication System

1 is a structural diagram of a multiplexed frame of a multiplexing apparatus according to the present invention.

2 is an explanatory diagram showing the configuration of a flag produced in the voice mode by the flag generating circuit of the multiplexing apparatus according to the present invention;

3 is an explanatory diagram showing the configuration of a flag generated in the data mode by the flag generation circuit of the multiplexing apparatus according to the present invention;

4 is a configuration diagram of an embodiment of a multiplexing apparatus according to the present invention.

5 is an explanatory diagram showing sequential control timing provided in a voice mode by the event control circuit of the multiplexing apparatus according to the present invention.

FIG. 6 is an explanatory diagram showing sequential control timing provided when an audio mode, an FEC coding rate 1/2, and a preamble length 192 are operated by an event control circuit of a multiplexing apparatus according to the present invention. FIG.

* Explanation of symbols for main parts of the drawings

10: timing control circuit 20: event control circuit

30: flag generation circuit 40: start message generation circuit

50: traffic data buffer circuit 60: signaling data buffer circuit

70: output gate circuit

The present invention provides traffic data (voice or continuous digital data) and additional signaling data to transmit additional signaling data between terminal earth stations in a satellite communication system such as DGS-200 (DAMA-SCPC SATELLITE GROUND SYSTEM-200). The present invention relates to a multiplexing device for multiplexing.

There are two types of data multiplexed and transmitted by the multiplexing device of the DGS-200 satellite communication system.

First, the signaling data after the traffic channel establishment includes the called terminal station subscriber number, call release number, channel status confirmation message, and user binary data.

Second, there is background noise level data for transmitting the background noise level value of the transmitting voice channel when operating in the voice mode.

The DGS-200 satellite communication system consists of one central station and multiple terminal earth stations, and the traffic channel between the terminal earth stations is provided by a single channel carrier (DAMA) based on a Demand Assigned Multiple Access (DAMA) method through a service channel. The traffic channel is established by SCPC: Single Channel Per Carrier. After the traffic channel is established, the subscriber of the terminating terminal earth station transmits the subscriber's telephone number of the terminating terminal earth station to the terminating terminal earth station in order to call the subscriber of the terminating terminal earth station, or to confirm the connection maintenance state of the traffic channel. The channel status confirmation message and the call release signal after completing the call shall be exchanged between the terminal earth stations.

In addition, since DGS-200 satellite communication system is set to voice mode, voice data is transmitted only when voice is detected by voice activation detector during operation. It must be inserted.

Accordingly, the present invention provides a background noise level for the sender's voice channel or to independently transmit call connection-related messages and low-speed user binary data without interrupting in-service traffic communication. ), Which is not provided in a conventional satellite communication system in which a traffic channel is established and operated by a single channel carrier method for transmitting data through a traffic channel with a transmission voice data burst or by a request-allocated multiple access method among satellite communication systems. It is an object of the present invention to provide a multiplexing device that can independently transmit additional signaling data when transmitting voice data or continuous digital data.

In order to achieve the above object, the present invention, from the outside receiving the transmission voice data burst on / off signal, channel unit operation on / off signal, channel unit operation mode signal, traffic data word clock input initialization signal and traffic data buffer Timing control means for outputting a write clock and a traffic data buffer reset signal; It is driven according to the initialization signal of the timing control means, and receives the Forward Error Correction (FEC) code rate, preamble length data and the multiplexer output clock from the outside to sequentially control the operation of each component. Event control means for outputting a control signal and a multiplexed frame timing signal; Flag generation means for receiving a voice on / off signal, a noise level on / off signal, and a signaling data on / off signal from an external source, generating a flag according to a control signal of the event control means, and outputting the flag according to an output clock; A start message (SOM) generating means for generating a start message (SOM) in synchronization with a control signal of the event control means and outputting the start message (SOM) according to an output clock; During the time of external transmission synchronizer and channel encoder processing delay time and start message (SOM) and flag (FLAG) are inserted into a multiplexed frame, traffic data inputted from the outside is stored / delayed according to the control signal of the event control means. Traffic data buffering means for outputting according to the output clock; A signaling data buffering means for receiving and storing signaling data or background noise level data every frame from an external channel unit processor and outputting the signal according to an output clock according to a control signal of the event control means; And a start message (SOM), a flag, traffic data and signaling data or a background noise level data provided by the flag generating means, the start message (SOM) generating means, the traffic data buffering means and the signaling data buffering means, respectively. It characterized in that it comprises an output means for receiving the output to generate one multiplexed frame to the outside.

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

1 is a structural diagram of a multiplexed frame of a multiplexing apparatus according to the present invention, and shows a structure of a frame for multiplexing signaling data and traffic data used in the present invention.

The multiplexed frame includes an 8-bit Start of Message (SOM) for acquiring frame synchronization at the receiving end, a 2-bit flag (FLAG) for indicating the data structure of the frame, and a 1260-bit voice or Or traffic data, which is continuous digital data, and 10 bits of signaling data or background noise level data, and the total length of the multiplexed frame is 1280 bits.

The bit structure of the 8-bit start message (SOM) is 0000 1101, and the structure of the 2-bit flag (FLAG) is generated like the second degree when operating in the voice mode and the third degree when operating in the data mode and multiplexed. It is inserted into the frame.

4 is a diagram illustrating an embodiment of a multiplexing apparatus according to the present invention, in which 10 is a timing control circuit, 20 is an event control circuit, 30 is a flag (FLAG) generating circuit, and 40 is a start message (SOM). ), 50 denotes a traffic data buffer circuit, 60 denotes a signaling data buffer circuit, and 70 denotes an output gate circuit.

The multiplexing apparatus according to the present invention is executed in two modes of operation, voice mode and data mode, according to an external control signal.

First, the operation in the case of operating in the voice mode is as follows.

When the timing control circuit 10 receives the transmission voice data burst on signal provided from an external transmission synchronization device and outputs an initialization signal synchronized with the output clock of the multiplexing device, the event control circuit 20 is driven according to this initialization signal. At the same time, when the timing control circuit 10 outputs a traffic data buffer write clock at an input rate synchronized with an adaptive differential pulse code modulation (ADPCM) word block input from the outside, the traffic data buffer circuit 50 generates the traffic data. Starts storing the traffic data from the outside according to the buffer write clock.

The overall operations of the multiplexing device are sequentially controlled by the control signals of the event control circuit 20 which has started to drive. These control signals are generated by decoding the output of the counter that counts 1,280 in the event control circuit 20, and the flag generating circuit 30 and the start message (sequentially and repeatedly) until the transmission burst off signal is applied sequentially and repeatedly as shown in FIG. SOM) is provided to the generation circuit 40, the traffic data buffer circuit 50, and the signaling data buffer circuit 60 to form a multiplexed frame.

The event control circuit 20 outputs the multiplexed frame timing signals that vary depending on the Forward Error Correction (FEC) coding rate input from the outside and the length of the preamble provided by the external transmission synchronization device. For example, if the FEC code rate is 1/2 and the preamble length is 192, the preamble insertion 192 + unique word insertion 32-channel encoder processing delay 12 = 212 of the external transmission synchronization device, i.e. Traffic data is stored / delayed in the traffic data buffer circuit 50 during processing delay time due to external transmission synchronization device and channel encoder for a total of 212 clock periods, followed by 8 bits by the start message (SOM) generation circuit 40 in succession. 1,260 bits of traffic generated by generating a start message (SOM) of the SMM and inserted into the multiplexed frame, and then inserted into the multiplexed frame by the flag FLAG generating circuit 30, and then delayed for 212 clock periods. Data is read from the address stored first in the traffic data buffer circuit 50, inserted into the multiplexed frame, and then 10-bit signaling data stored in the signaling data buffer circuit 60. Completes the configuration of the multiplexed frame 1 by inserting the level of background noise in the data multiplex frame. This frame composition operation is repeatedly performed by the event control circuit 20 of the multiplexing device until the transmission burst off signal is applied.

As a result of the above operation, a flag, a start message, respectively provided by the flag generation circuit 30, the start message (SOM) generation circuit 40, the traffic data buffer circuit 50 and the signaling data buffer circuit 60, respectively, The traffic data and the signaling data or the background noise level data are made into one output stream by the output gate circuit 70, and the control timing of the control signal provided by the event control circuit 20 to construct the multiplexed frame is controlled. 6 is like help.

On the other hand, the operation in the data mode is as follows.

When the timing control circuit 10 receives the channel unit operation ON signal from the outside and outputs an initialization signal synchronized with the output clock of the multiplexing device, the event control circuit 20 is driven according to the initialization signal, and at the same time, the timing control circuit ( 10) outputs a traffic data buffer write clock at an input rate synchronized with a continuous digital data word clock input from the outside, the traffic data buffer circuit 50 stores the traffic data input from the outside according to the traffic data buffer write clock. To start.

The overall operation of the multiplexing device is sequentially controlled by the control signal of the event control circuit 20 which has started to be driven, and these control signals are produced by decoding the output of the counter which counts 1,280 in the event control circuit 20. The control signals are sequentially and repeatedly applied to the flag FLAG generating circuit 30, the start message SOM generating circuit 40, the traffic data buffer circuit 50, and the signal until the channel unit operation off signal is applied. The ring data buffer circuit 60 is provided to control the multiplexed frames.

The event control circuit 20 provides necessary timings by using a control circuit that provides control timings corresponding to the FEC coding rate 1/2 and the preamble length 192 of the voice mode shown in FIG. That is, when the channel unit operation ON signal is applied, traffic data is stored / delayed in the traffic data buffer circuit 50 for a total of 212 clocks, and then an 8-bit start message is generated by the start message (SOM) generation circuit 40. After generating and inserting the (SOM) into the multiplexed frame, the flag generation circuit 30 inserts a 2-bit flag into the multiplexed frame and stores the 1.260-bit traffic data delayed for 212 clock periods in the traffic data buffer. One multiplexed frame is obtained by first inserting the data of the address stored in the circuit 50 first into the multiplexed frame, and then inserting 10-bit signaling data stored in the signaling data buffer circuit 60 into the multiplexed frame. Complete the configuration.

As a result, the flags, start message, traffic data and the like provided from the flag generation circuit 30, the start message (SOM) generation circuit 40, the traffic data buffer circuit 50, and the signaling data buffer circuit 60, respectively. The signaling data is made into one output stream by the output gate circuit 70, and this frame configuration operation is repeated by the event control circuit 20 until the channel unit operation off signal is applied.

Signaling data or background noise level data is written to the signaling data buffer circuit 60 by 10 bits at every frame interval only when there is data to be transmitted by an external channel unit processor. Frame timing is provided by the event control circuit 20 at every frame interval in order to receive signaling data or background noise level data from an external channel unit processor.

When the terminal earth station is operated in the voice mode and the data mode, when the present invention is applied, 32 kbps voice data is operated in the voice mode, and 32 or 64 kbps continuous digital data is operated in the data mode. Is sent through.

As described above, the present invention implements a multiplexing apparatus that multiplexes traffic data, signaling data, or background noise level data according to an operation mode to transmit additional low-speed signaling data between terminal earth stations of the DGS-200 satellite communication system. It has the following distinctive effects.

First, a single multiplexing device may selectively execute one mode according to a channel unit operation mode selection signal among two modes of a voice mode and a data mode to provide a multiplexed frame.

Second, while transmitting digital voice data or continuous digital data at a rate of 32 kbps over a traffic channel, additional signaling data or background noise level data can be transmitted at speeds of up to 254 bps independently of the traffic data.

Third, additional signaling data can be transmitted at a maximum speed of 508 bps independently of the traffic data while simultaneously transmitting 64 kbps continuous digital data through the traffic channel.

Fourthly, when the multiplexing device is operated in the voice mode, the structure of the multiplexed frame composed of three types of data (voice data, signaling data, sender background noise level data) can be transmitted to the receiver using a 2-bit flag (FLAG). Can be.

Fifth, when the multiplexing device is operated in the data mode, the structure of the multiplexing frame composed of two types of data (continuous data and signaling data) can be transmitted to the receiver using a 2-bit flag FLAG.

Claims (2)

Timing to output initialization signal, traffic data buffer write clock, and traffic data buffer reset signal from external voice data burst on / off signal, channel unit operation on / off signal, channel unit operation mode signal, traffic data word clock Control means; It is driven according to the initialization signal of the timing control means, and receives the Forward Error Correction (FEC) code rate, preamble length data and the multiplexer output clock from the outside to sequentially control the operation of each component. Event control means for outputting a control signal and a multiplexed frame timing signal; Flag generation means for receiving a voice on / off signal, a noise level on / off signal, and a signaling data on / off signal from an external source, generating a flag according to a control signal of the event control means, and outputting the flag according to an output force; A start message (SOM) generating means for generating a start message (SOM) in synchronization with a control signal of the event control means and outputting the start message (SOM) according to an output clock; Store / transmit the traffic data input from the outside according to the control signal of the event control means during the time of external transmission synchronizer and channel encoder processing delay time and start message (SOM) and flag (FLAG) are inserted into the multiplexed frame. Traffic data buffering means for delaying and outputting the data according to the output clock; A signaling data buffering means for receiving and storing signaling data or background noise level data every frame from an external channel unit processor and outputting the signal according to an output clock according to a control signal of the event control means; And a start message (SOM), a flag, traffic data and signaling data or a background noise level data provided by the flag generating means, the start message (SOM) generating means, the traffic data buffering means and the signaling data buffering means, respectively. And an output unit for generating one multiplexed frame and outputting the multiplexed frame to the outside. 2. The apparatus of claim 1, wherein the multiplexed frame comprises: an 8-bit start message (SOM) for acquiring synchronization of the frame at the receiving side; A 2-bit flag FLAG for indicating the data structure of the frame; Traffic data which is voice / continuous digital data; And additional signaling data or background noise level data.