JP4502922B2 - Transmitter control system - Google Patents

Description

  The present invention relates to a broadcast relay station transmitter control system, and more particularly to a relay station transmitter control system for relaying a terrestrial digital television broadcast wave to a general household.

  As a method of starting and stopping the relay station transmitter that relays terrestrial analog TV broadcast waves to general households, etc., monitor the presence of video synchronization signal, start the transmitter with `` with synchronization signal '', `` A method is generally used in which the transmitter is stopped without a synchronization signal. However, since there is no video synchronization signal in terrestrial digital broadcasting, a method for starting and stopping the relay station transmitter in place of the above-described method is required.

  As a method for monitoring and controlling a device such as this type of relay station transmitter, a method using AC (Aux Channel) in a TS (Transport Stream) packet is known (see, for example, Patent Document 1). In this technique, in the transmission and multiplexing configuration control (TMCC) storage area in the TS packet, the AC1 area that can be used for transmission of control / monitoring information for simultaneously controlling and monitoring each relay stage, and any relay The CC1 area and CC2 area that can be used for transmission of control / monitoring information for individually controlling / monitoring stages are defined. The control information is assumed to be on / off control, system switching, delay time control, etc. for the broadcast transmitter of each relay station, and alarm information is assumed as the monitoring information.

Japanese Unexamined Patent Publication No. 2004-165753 (pages 6-9, FIG. 1)

  However, in the above-described prior art, the relay station performs multi-stage relay by transmission between a plurality of stations connected by an STL (Studio to Transmitter Link) / TTL (Transmitter to Transmitter Link) line. It is considered that there is no plan for a relay station that directly relays (broadcasts) terrestrial digital TV broadcast waves to ordinary homes. Because of such relaying, it is necessary to study the format structure between TS packets and STL / TTL transmission packets, and the specifications for simultaneous transmission of control and monitoring information in multistage relays are at issue.

  That is, in the relay station, the received STL / TTL transmission packet must be once converted into the broadcast TS packet format, and the control / monitoring information must be extracted once, and the control / monitoring information is sent to the relay station in the subsequent stage. Therefore, when converting a broadcast TS packet to an STL / TTL transmission packet, accumulation of delay time due to a process of superimposing control / monitor information again is regarded as a problem. The technique described in Patent Document 1 intends to solve this problem.

  Therefore, in terrestrial digital broadcasting, there are still specific methods for starting / stopping control of a plurality of relay station transmitters in place of the relay station starting / stopping method using the video synchronization signal in the above-mentioned terrestrial analog television broadcasting. Not established.

  In the technique described in Patent Document 1, there is no particular area for individually specifying relay stations to be controlled and monitored. Therefore, the CC1 area and CC2 area for individual control and monitoring are specified as specific relays. This is considered to be linked with the station, which is inconvenient for individually controlling and monitoring a large number of relay stations.

  Accordingly, an object of the present invention is to provide a transmitter control system capable of performing simultaneous or individual automatic start and stop control of a plurality of relay station transmitters without using a dedicated control line.

The transmitter control system of the present invention is a transmitter control system for a relay station that relays a terrestrial digital television broadcast wave to a general household. A broadcast station that transmits a terrestrial digital television broadcast wave can be classified into broadcast and non-broadcast. A broadcast / non-broadcast flag extraction unit (11 in FIG. 1) that extracts a broadcast / non-broadcast flag indicated by a binary signal from the header portion of the TS packet, and a broadcast / non-broadcast flag extracted by the broadcast / non-broadcast flag extraction unit And a logic circuit that performs a logical operation on a designated transmitter ON / OFF signal that indicates each relay station using a binary signal to indicate whether the transmitter is on or off, and a transmitter ON / OFF flag for each relay station that has been logically operated Are sequentially inserted into the reserved bits of the TMCC information together with the relay station identification ID (12 in FIG. 1), and a mixer (13 in FIG. 1) that incorporates the TMCC information in which the transmitter ON / OFF flag is incorporated into the TS packet. ) And T from the mixer A distributor (15 in FIG. 1) that distributes the S packet to each relay station, and each relay station that receives the terrestrial digital television broadcast wave extracts a TMCC information (FIG. 1) that extracts TMCC information of the received TS packet. 1) 22) and the transmitter ON / OFF flag is extracted from the reserved bits of the TMCC information extracted by the TMCC extraction unit, and when the relay station identification ID of the reserved bits matches the ID of the transmitter, A sign determination unit (23 in FIG. 1) that outputs a start command or a stop command according to an ON / OFF flag, and a transmitter (25 in FIG. 1) that starts or ends transmission of a TS packet received according to the start command or stop command The transmitter of the relay station can be turned on by a designated transmitter ON / OFF signal only when the broadcast / non-broadcast flag indicates broadcast .

  According to the present invention, the transmitter ON / OFF flag and the relay station identification ID for the transmitter of each relay station are inserted into the reserved bits of the TMCC information, and the TS packet is transmitted to each relay station. TMCC information is extracted from the TS packet, and when its own transmitter matches the relay station identification ID, the transmitter ON / OFF flag is used to control the start and stop of the transmitter. It is possible to obtain an effect that it is possible to perform start and stop control of transmitters of many relay stations that relay (broadcast) waves to ordinary homes and the like without using a dedicated control line.

  A TS packet transmitted to each relay station in terrestrial digital television broadcasting includes TMCC information for transmitting system identification, layer configuration, transmission parameters, and the like. The TMCC information composed of 204 bits includes 15 reserved bits for expansion. Using the 15 bits for extension, the relay station transmitter is controlled by transmitting a start signal and a stop signal of the relay station transmitter.

  The transmitter control system of the present invention assigns a control signal of a transmitter of a terrestrial digital broadcast relay station to TMCC information in a TS packet, thereby enabling activation of a plurality of relay station transmitters without using a dedicated control line. Perform stop control. In addition, by using broadcast / non-broadcasting flag (broadcasting flag) in the TS packet header, it is possible to start / stop relay station transmitters all at once, thereby enabling multiple relays using video synchronization signals in terrestrial analog broadcasting Provided is a transmitter control system for a terrestrial digital broadcast relay station that replaces the station activation and deactivation method. Embodiments of the present invention will be described below with reference to the drawings.

  In the TMCC information composed of 204 bits, as shown in FIG. 2, there are 15 reserved bits for expansion. In the present invention, the relay station transmitter is controlled by transmitting the start / stop control signal of the relay station transmitter and the relay station identification ID using the 15 bits for extension.

  Further, by extracting the broadcast / non-broadcasting flag of the system management descriptor existing in the PID (Personal Identity Number) part of the TS packet header and entwining it with the ON / OFF control signal of each relay station, the relay station Start / stop automatically.

  FIG. 1 is a block diagram showing an embodiment of a transmitter control system of the present invention. This transmitter control system includes a broadcast station 10 that includes a broadcast / non-broadcast flag extraction unit 11, an encoding device 12, a mixer 13, a QAM modulator 14, and a distributor 15, and transmits terrestrial digital television broadcast waves; A QAM demodulator 21, a TMCC extracting unit 22, a code discriminating unit 23, an OFDM modulator 24, and each receiving a terrestrial digital television broadcast wave from the broadcasting station 10 and directly relaying (broadcasting) it to a general home or the like. The transmitter 25 is composed of a large number of relay stations 20.

The broadcast / non-broadcast flag extraction unit 11 of the broadcast station 10 extracts the broadcast / non-broadcast flag from the PID portion of the TS packet header. The encoding device 12 sequentially inserts the transmitter ON / OFF flag of each relay station into the reserved bits of the TMCC information together with the relay station identification ID. The transmitter ON / OFF flag is a logical sum of the broadcast / non-broadcast flag extracted by the broadcast / non-broadcast flag extraction unit 11 and the transmitter ON / OFF signal designated for each relay station.

  The mixer 13 incorporates the TMCC information in which the relay station transmitter ON / OFF flag is incorporated into the TS packet. The QAM modulator 14 performs QAM (Quadrature Amplitude Modulation) modulation to transmit TS packets to each relay station 20. The distributor 15 distributes the TS signal modulated by the QAM modulator 14 to each relay station 20.

  The QAM demodulator 21 of each relay station 20 demodulates the TS signal modulated by the QAM modulator 14. The TMCC extraction unit 22 extracts TMCC information of the demodulated TS packet. The code discrimination unit 23 extracts the transmitter ON / OFF flag from the reserve bits of the TMCC information extracted by the TMCC extraction unit 22, and when the relay station identification ID of the reserve bits matches the ID of the transmitter 25, the transmitter ON A start command or a stop command is output to the transmitter 25 according to the / OFF flag.

  The OFDM modulator 24 performs OFDM (Orthogonal Frequncy Division Multiplexing) modulation on the demodulated TS packet, and the transmitter 25 starts or ends transmission (broadcasting) of the OFDM-modulated TS packet according to the start command or the stop command. .

  Next, the operation of the transmitter control system will be described using specific numerical values. As the bit allocation to the 15 reserved bits in the TMCC information, the first bit is used as the ON / OFF flag of the transmitter, and the remaining 14 bits are used as the relay station identification ID number. In this case, it is possible to control the relay station transmitter of 2 to the 14th power, that is, 16,384 stations at the maximum by the 14-bit relay station identification ID number. As the transmitter ON / OFF flag, 0 is assigned to ON and 1 is assigned to OFF. Each relay station is assigned in advance a unique relay station identification ID that does not overlap with other relay stations.

  In FIG. 2, the broadcast / non-broadcast flag extraction unit 11 extracts the broadcast / non-broadcast flag of the system management descriptor existing in the PID portion of the TS packet header. The broadcast / non-broadcast flag is 0 for broadcast and 1 for non-broadcast. The extracted broadcast / non-broadcast flag and the transmitter ON / OFF signal of each relay station are logically summed and sent to the encoding device 12.

  Here, if the transmitter ON / OFF signal of each relay station is defined as 0 when ON and 1 as OFF, the OR of the relay station transmitter is ON when the broadcast / non-broadcast flag is 0 (broadcast). All relay stations with the / OFF signal 0 (ON) can be activated. When the broadcast / non-broadcast flag is 1 (non-broadcast), all relay stations are turned on regardless of the relay ON / OFF signal of the relay station. Can be turned off.

  The encoding device 12 sequentially inserts the transmitter ON / OFF flag and the relay station identification ID of each relay station to be controlled into the reserved bits in the TMCC information. The inserted TMCC information is incorporated into the TS packet by the mixer 13. At this time, for example, when the ID1 relay station transmitter is started and the ID2 transmitter is stopped, first, 000000000000001 is inserted as a transmitter control signal into the reserve bit in the TMCC information and incorporated in the TS packet. Then, the data with 100000000000010 inserted is incorporated into the next TS packet and transmitted.

  The TS packet is QAM modulated by the QAM modulator 14 and transmitted to each relay station through the distributor 15. In each relay station, TMCC information is extracted by the TMCC extraction unit 22 from the TS packet demodulated by the QAM demodulator 21. The code discriminating unit 23 extracts a reserved bit from the TMCC information extracted by the TMCC extracting unit 22, and discriminates a relay station identification ID and a transmitter ON / OFF flag.

  Then, the relay station identification ID set in advance in the code discrimination unit 23 is compared with the relay station identification ID transmitted as TMCC information, and if they match, if the transmitter ON / OFF flag is 0, For example, a start command is output to the transmitter 25, and if it is 1, a stop command is output.

The block diagram which shows one Example of the transmitter control system of this invention The figure which shows the content of the reserve bit for expansion of the QAM modulator information employ | adopted by this invention

Explanation of symbols

10 Broadcasting station
11 Broadcast / non-broadcast flag extractor
12 Encoder
13 Mixer
14 QAM modulator
15 Distributor
20 Relay station
21 QAM demodulator
22 QAM extractor
23 Code discrimination part
24 OFDM modulator
25 Transmitter

Claims (2)

In the transmitter control system of a relay station that relays terrestrial digital TV broadcast waves to general households,
The broadcasting station that transmits the terrestrial digital television broadcast wave is:
A broadcast / non-broadcast flag extraction unit that extracts a broadcast / non-broadcast flag indicating whether broadcast or non-broadcast is indicated by a binary signal from the header portion of the TS packet;
Logically calculate the broadcast / non-broadcast flag extracted by the broadcast / non-broadcast flag extraction unit and the designated transmitter ON / OFF signal that indicates whether the transmitter is on or off with a binary signal for each relay station Logic circuit ;
An encoding device that sequentially inserts a transmitter ON / OFF flag of each relay station that has been logically calculated into a reserve bit of TMCC information together with a relay station identification ID;
A mixer for incorporating TMCC information in which the transmitter ON / OFF flag is incorporated into a TS packet;
A distributor for distributing TS packets from the mixer to each relay station;
Each relay station that receives the terrestrial digital television broadcast wave,
A TMCC extractor for extracting TMCC information of the received TS packet;
The transmitter ON / OFF flag is extracted from the reserved bits of the TMCC information extracted by the TMCC extraction unit, and when the relay station identification ID of the reserved bits matches the ID of the transmitter , the transmitter ON / OFF A sign determination unit that outputs a start command or a stop command according to an OFF flag ;
Comprising a transmitter to start or end the transmission of the received TS packets in accordance with the start instruction or a stop instruction,
A transmitter control system characterized in that a transmitter of a relay station can be turned on by the designated transmitter ON / OFF signal only when the broadcast / non-broadcast flag indicates broadcast .   2. The encoder according to claim 1, wherein the encoder inserts the transmitter ON / OFF flag in one of the reserved bits, and inserts the relay station identification ID in the remaining bits of the reserved bits. Transmitter control system.

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