JP2022033170A - Broadcasting re-transmission device and broadcasting re-transmission method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct an excellent system that re-transmits advanced wide band digital satellite broadcasting to a subscriber's house via a network such as a cable TV network.

SOLUTION: A broadcast re-transmission device used for advanced wide band digital satellite broadcasting comprises: a tuner that demodulates a received satellite broadcasting wave including information on a program and TMCC information, outputs demodulation data including the information on the program, and can read part of the TMCC information not included in the demodulation data from a storage unit; a reading unit for reading first information, part of the TMCC information, from the storage unit of the tuner; an information creation unit for creating second information, information included in the TMCC information and differing from the first information; an information recovery unit for integrating the first information with the second information to recover part or all of the TMCC information; and a stream generation unit for generating a stream including the demodulation data and the TMCC information.

SELECTED DRAWING: Figure 4

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a broadcast retransmission device and a broadcast retransmission method.

Conventionally, a technique for transmitting content using an MMTP (MPEG Media Transport Protocol) packet has been developed.

For example, the Association of Radio Industries and Businesses, "Media Transport Method by MMT in Digital Broadcasting ARIB STD-B60 1.9 Edition", March 24, 2017 (Non-Patent Document 1), broadcasting using the MMT method. The system is disclosed.

In this broadcasting system, an MMT packet containing program information such as audio information and video information is stored in the payload of the IP packet. The IP packet is stored in the payload of the TLV (Type Length Value) packet.

Association of Radio Industries and Businesses, "Media Transport Method by MMT in Digital Broadcasting ARIB STD-B60 1.9 Edition", March 24, 2017 International Telecommunication Union Radiocommunication Sector, "Recommunication ITU-R BT.1869", March 2010, [online], [Search on August 29, 2017], Internet <URL: http: // www. itu. int / dms_pubrec / itu-r / rec / bt / R-REC-BT. 1869-0-201003-I! !! PDF-E. pdf> Association of Radio Industries and Businesses, "Transmission method for advanced wideband satellite digital broadcasting ARIB STD-B44 2.1 version", March 25, 2016

For example, the Association of Radio Industries and Businesses, "Transmission Method for Advanced Broadband Satellite Digital Broadcasting ARIB STD-B44 2.1 Edition", Advanced Broadband According to the Method Disclosed on March 25, 2016 (Non-Patent Document 3). A technology capable of constructing an excellent system for retransmitting satellite digital broadcasting to a subscriber's home via a network such as a cable TV network is desired.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to construct an excellent system for retransmitting advanced broadband satellite digital broadcasting to a subscriber's home via a network such as a cable television network. It is to provide a broadcast retransmission device and a broadcast retransmission method capable of.

(1) In order to solve the above problems, the broadcast retransmission device according to a certain aspect of the present invention is a broadcast retransmission device used for advanced broadband satellite digital broadcasting, and is satellite broadcasting including program information and TMCC information. A tuner that receives a wave and demolishes it, outputs demodized data including the information of the program, and the TMCC information not included in the demodulated data can be partially read from the storage unit, and the TMCC from the storage unit of the tuner. A reading unit that reads out the first information that is a part of the information, an information creating unit that creates the second information that is included in the TMCC information and is different from the first information, and the above. From the information recovery unit that restores a part or all of the TMCC information by combining the first information read by the reading unit and the second information created by the information creation unit, and the tuner. A stream generation unit that generates a stream containing the received demodulation data and the TMCC information restored by the information restoration unit, and the stream generated by the stream generation unit are modulated to generate a retransmission credit broadcast wave. It is equipped with a broadcast wave generator.

(3) In order to solve the above problems, the broadcast retransmission method according to a certain aspect of the present invention is used for advanced broadband satellite digital broadcasting, receives and demolishes satellite broadcast waves including program information and TMCC information. A broadcast retransmission method in a broadcast retransmission device including a tuner that outputs demodulated data including the program information and that the TMCC information not included in the demodulated data can be partially read from the storage unit, and is a method of broadcasting retransmission of the tuner. A step of reading the first information that is a part of the TMCC information from the storage unit, and a step of creating a second information that is included in the TMCC information and is different from the first information. And the step of restoring a part or all of the TMCC information by combining the read first information and the created second information, the demodulation data received from the tuner, and the restored TMCC. It includes a step of generating a stream containing information and a step of modulating the generated stream to generate a retransmission credit broadcast wave.

The present invention can be realized not only as a broadcast retransmission device provided with such a characteristic processing unit, but also as a program for causing a computer to execute such a characteristic processing step. Further, the present invention can be realized as a semiconductor integrated circuit that realizes a part or all of the broadcast retransmission device, or can be realized as a system including the broadcast retransmission device.

According to the present invention, it is possible to construct an excellent system for retransmitting an advanced broadband satellite digital broadcast to a subscriber's home via a network such as a cable television network.

FIG. 1 is a diagram showing a configuration of a broadcast retransmission system according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a protocol stack of data transmitted by satellite broadcast waves in the broadcast retransmission system according to the embodiment of the present invention. FIG. 3 is a diagram showing an example of a TLV packet transmitted by a satellite broadcast wave in the broadcast retransmission system according to the embodiment of the present invention. FIG. 4 is a diagram showing a configuration of a broadcast retransmission device in the broadcast retransmission system according to the embodiment of the present invention. FIG. 5 is a diagram showing an example of a frame of a stream transmitted in the broadcast retransmission system according to the embodiment of the present invention. FIG. 6 is a diagram showing an example of a format of transmission TMCC information in the broadcast retransmission device according to the embodiment of the present invention. FIG. 7 is a diagram showing an example of the configuration of pointer / slot information of transmission TMCC information in the broadcast retransmission device according to the embodiment of the present invention. FIG. 8 is a flowchart defining an operation procedure when the broadcast retransmission device according to the embodiment of the present invention generates a retransmitted credit broadcast wave.

First, the contents of the embodiments of the present invention will be listed and described.

(1) The broadcast retransmission device according to the embodiment of the present invention is a broadcast retransmission device used for advanced broadband satellite digital broadcasting, and receives and demolishes satellite broadcast waves including program information and TMCC information. A tuner that outputs demographic data including the information of the program and partially reads the TMCC information not included in the demodulation data from the storage unit and a part of the TMCC information from the storage unit of the tuner. Read by the reading unit, the reading unit that reads the information of 1, the information creating unit that creates the second information that is included in the TMCC information and is different from the first information, and the reading unit. The information restoration unit that restores a part or all of the TMCC information by combining the first information and the second information created by the information creation unit, the demodulation data received from the tuner, and the demodulation data. It includes a stream generation unit that generates a stream containing the TMCC information restored by the information restoration unit, and a broadcast wave generation unit that modulates the stream generated by the stream generation unit to generate a retransmission credit broadcast wave. ..

In this way, by reading a part of the TMCC information from the tuner and creating the TMCC information excluding the read part by itself, the TMCC information included in the received satellite broadcast wave is restored. It is possible to retransmit satellite broadcast waves using a tuner that does not output at least part of it. Further, by remodulating the demodulated data output from the tuner, the carrier-to-noise ratio can be made larger than that of the original satellite broadcast wave, so that the data was transmitted via the broadcast retransmission device, for example, at the subscriber's house. It is possible to receive a broadcast wave and stably play back a program included in the received broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting advanced broadband satellite digital broadcasting to the subscriber's home via a network such as a cable television network.

(2) Preferably, the satellite broadcast wave includes a plurality of frames, and the broadcast retransmission device further detects the timing of the frame based on the demodulation data received from the tuner, and the detected timing. A unit for adjusting the frequency of the clock used in the stream generation unit and the broadcast wave generation unit is provided based on the above.

With such a configuration, the frequency of the clock of the retransmission credit broadcast wave can be adjusted to the frequency of the transmission clock of the satellite broadcast wave by a simple process.

(3) The broadcast retransmission method according to the embodiment of the present invention is used for advanced broadband satellite digital broadcasting, receives and demolishes satellite broadcast waves including program information and TMCC information, and demolishes including the program information. The TMCC information that outputs data and is not included in the demodulated data is a broadcast retransmission method in a broadcast retransmission device including a tuner that can be partially read from the storage unit, and the TMCC information is transmitted from the storage unit of the tuner. A step of reading out the first information which is a part of the above, a step of creating a second information which is information included in the TMCC information and different from the first information, and a step of reading out the first information. By combining the information of the above and the created second information, a stream including the step of restoring a part or all of the TMCC information, the demodulation data received from the tuner, and the restored TMCC information is generated. It includes a step and a step of modulating the generated stream to generate a retransmission credit broadcast wave.

In this way, by reading a part of the TMCC information from the tuner and creating the TMCC information excluding the read part by itself, the TMCC information included in the received satellite broadcast wave is restored. It is possible to retransmit satellite broadcast waves using a tuner that does not output at least part of it. Further, by remodulating the demodulated data output from the tuner, the carrier-to-noise ratio can be made larger than that of the original satellite broadcast wave, so that the data was transmitted via the broadcast retransmission device, for example, at the subscriber's house. It is possible to receive a broadcast wave and stably play back a program included in the received broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting advanced broadband satellite digital broadcasting to the subscriber's home via a network such as a cable television network.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals and the description thereof will not be repeated. In addition, at least a part of the embodiments described below may be arbitrarily combined.

FIG. 1 is a diagram showing a configuration of a broadcast retransmission system according to an embodiment of the present invention.

With reference to FIG. 1, the broadcast retransmission system 301 includes a broadcast retransmission device 101, a cable television network 10, and a plurality of STBs (Set Top Boxes) 131. The STB 131 is connected to the TV monitor 133.

The broadcast retransmission system 301 is not limited to the configuration including a plurality of STB131s, and may be configured to include one STB131.

The broadcast retransmission device 101 is provided, for example, in the station building 151 of a business operator that provides cable television broadcasting. The STB 131 and the TV monitor 133 are provided in the subscriber's house 152.

For example, an external antenna 81 is connected to the broadcast retransmission device 101. The broadcast retransmission device 101 receives, for example, a satellite broadcast wave including a stream.

The stream contains program information and the like. The program information includes, for example, audio information, video information, EPG (Electronic Program Guide) information, SI information (Service Information), subtitle information, and the like.

The audio and video information is, for example, compressed and encrypted according to a predetermined method.

The broadcast retransmission device 101 receives, for example, satellite broadcast waves transmitted from a broadcast satellite for advanced broadband satellite digital broadcasting (not shown) for relaying a stream from a broadcast station via an external antenna 81.

FIG. 2 is a diagram showing an example of a protocol stack of data transmitted by satellite broadcast waves in the broadcast retransmission system according to the embodiment of the present invention. FIG. 2 shows a protocol stack using TLV packets.

With reference to FIG. 2, TLV packets are often used for transmission such as 4K UHDTV (Ultra High Definition Television) or 8K UHDTV according to standards such as 2160p or 4320p.

In the example shown in FIG. 2, the satellite broadcast wave includes, for example, TMCC information, AC information and TLV packets.

FIG. 3 is a diagram showing an example of a TLV packet transmitted by a satellite broadcast wave in the broadcast retransmission system according to the embodiment of the present invention. FIG. 3 shows an example of a packet having a header containing information indicating a data type, such as Internet Telecommunications Union Radiocommunication Sector, “Recommunication ITU-R BT.1869”, March 2010, [online], [Heisei. Searched on October 12, 2017], Internet <URL: http: // www. itu. int / dms_pubrec / itu-r / rec / bt / R-REC-BT. 1869-0-201003-I! !! PDF-E. The format of the TLV packet according to the standard of pdf> (Non-Patent Document 2) is shown.

The TLV packet includes a TLV header and a TLV payload. The TLV header includes a "start code" field containing a value of "01", a "future reservation" field, a "packet type" field, and a "length" field, the length of these fields. Are 2 bits, 6 bits, 8 bits and 16 bits, respectively.

Values such as "0x01", "0x02", "0x03", and "0xFF" are stored in the "packet type" field. Here, the numbers starting with "0x" mean that the numbers after "0x" are represented by hexadecimal numbers.

When "0x01" is stored in the "packet type" field, the TLV packet 61 includes an IPv4 packet that is the total data length of the value stored in the "length" field in the TLV payload.

Further, when "0x02" is stored in the "packet type" field, the TLV packet 62 includes an IPv6 packet which is the total data length of the value stored in the "length" field in the TLV payload.

Further, when "0x03" is stored in the "packet type" field, the TLV packet 63 includes an IP packet having the total data length of the value stored in the "length" field in the TLV payload. The compressed IP packet is, for example, an IP packet in which the IP header is compressed.

Further, when "0xFF" is stored in the "packet type" field, the TLV packet 64 includes null data which is the total data length of the values stored in the "length" field in the TLV payload. Hereinafter, a TLV packet containing null data in the TLV payload is also referred to as a TLV null packet.

With reference to FIG. 2 again, for example, NTP (Network Time Protocol) data for time synchronization, IP-SI data, time information, MMT packet, or data transmission method is stored in UDP (User Datagram Protocol) / IP packet. Will be done. Video information, audio information, MMT-SI data, and other information are stored in the MMT packet.

The TLV packets 61 to 63 (hereinafter, also referred to as TLV information packets) store such UDP / IP packets.

With reference to FIG. 1 again, the broadcast retransmission device 101 acquires program information from the satellite broadcast wave, and transmits the broadcast wave including the acquired program information to each subscriber's home 152 via the cable television network 10. do.

The STB 131 receives, for example, a broadcast wave transmitted from the broadcast retransmission device 101 via the cable television network 10.

When the STB 131 receives a broadcast wave from the broadcast retransmission device 101, it acquires program information from the received broadcast wave, decodes audio information and video information based on the acquired program information, and decodes the audio information. And the video information is transmitted to the TV monitor 133.

The TV monitor 133 reproduces the program based on the audio information and the video information received from the STB 131.

FIG. 4 is a diagram showing a configuration of a broadcast retransmission device in the broadcast retransmission system according to the embodiment of the present invention.

With reference to FIG. 4, the broadcast retransmission device 101 includes a tuner 11, a read unit 12, an information creation unit 13, an information restoration unit 14, a stream generation unit 15, a broadcast wave generation unit 16, and an adjustment unit. 17 and a VCO (Voltage-Controlled Oscillator) 18. The tuner 11 includes a receiving unit 21, a demodulation unit 22, and a storage unit 23. The stream generation unit 15 includes a FIFA 31.

The VCO 18 generates a reference clock. More specifically, the VCO 18 is capable of generating a clock having a frequency corresponding to the magnitude of the voltage received from the regulator 17 in a predetermined frequency range including 33.7571 MHz.

The tuner 11 receives and demodulates a satellite broadcast wave including program information and TMCC information, and outputs demodulated data including program information and not containing TMCC information.

More specifically, the receiving unit 21 in the tuner 11 receives satellite broadcasting waves including program information and TMCC information transmitted from a broadcasting satellite for advanced broadband satellite digital broadcasting via an external antenna 81, and receives satellite broadcasting. The wave is output to the demodulator 22.

The satellite broadcast wave in the broadcast retransmission system 301 includes, for example, the above-mentioned TLV program packet which is a TLV packet including program information, time adjustment information for performing time adjustment between devices using Coordinated Universal Time, and the like. Includes and follows the MMT method. The NTP data is an example of time adjustment information.

The demodulation unit 22 acquires a stream included in the satellite broadcast wave. More specifically, the demodulation unit 22 demodulates the satellite broadcast wave received from the reception unit 21 and converts it into a digital signal. Then, the demodulation unit 22 generates a stream including the TLV program packet, the time adjustment information, and the like based on the digital signal, and stores the TMCC information in the generated stream in the storage unit 23.

Further, the demodulation unit 22 outputs information other than the TMCC information in the generated stream as demodulation data to the information creation unit 13, the stream generation unit 15, and the adjustment unit 17.

It is stipulated that a satellite broadcast wave includes a frame for efficiently transmitting a plurality of streams of an advanced broadband satellite digital broadcast. The transmission of the stream is performed while maintaining the structure of the frame.

The frame can contain a plurality of streams corresponding to programs of up to 16 broadcasting stations. Each stream is distinguished by using, for example, the transmission stream ID included in the MMT packet in the TLV packet.

FIG. 5 is a diagram showing an example of a frame of a stream transmitted in the broadcast retransmission system according to the embodiment of the present invention. FIG. 5 shows the structure of the frame according to the standard of Non-Patent Document 3.

FIG. 5 shows a case where one frame contains three streams corresponding to programs of three broadcasting stations.

With reference to FIG. 5, the frame is composed of 120 slots. That is, for example, 40 slots are assigned to one stream. For example, the stream of stream number SN1 is assigned slots 40 from slot 1, the stream of stream number SN2 is assigned slots 41 to 80, and the stream of stream number SN3 is assigned slots 81 to 120. Assigned.

The stream is divided and stored in the slot. Also, the time length of the frame is 33 milliseconds.

The slot contains 44880 bits of demodulated data and 1600 bits of TMCC information in order from the beginning.

The demodulated data is composed of a slot header, a main signal, a BCH code parity, a stuff bit, and an LDPC (Low Density Party Check) code parity field in this order from the beginning.

The data length of the slot header is 176 bits.

The data length of the main signal is variable. One or a plurality of divided TLV packets and the like are stored in the field of the main signal.

When the demodulated data includes a TLV packet, the first 16 bits of the slot header indicate the first TLV instruction.

The head TLV instruction indicates the position of the head header of the first TLV packet in the main signal of each slot by the number of bytes from the head of the field of the main signal.

The data length of BCH code parity is 192 bits. The data length of the stuff bit is 6 bits. The data length of the LDPC code parity is a variable length.

The TMCC information is composed of a field of 280-bit fixed-length basic TMCC information and a field of 1320-bit fixed-length transmission TMCC information and the like, in order from the beginning.

The field of the basic TMCC information includes a field of a 120-bit fixed-length synchronization signal and a field of 160-bit fixed-length signal point arrangement information in this order from the beginning.

The TMCC information is divided and stored in a plurality of slots. More specifically, the sync signal is stored over 24 slots. The signal point arrangement information is stored over 24 slots to 120 slots depending on the combination of modulation methods.

Further, the information of 31680 bits obtained by adding 192 bits of BCH code parity and 22066 bits of LDPC code to the transmission TMCC information of 9422 bits, which is the sum of 9240 bits of 1320 bits × 7 slots and 182 bits of the 8th slot, is 24. Stored across slots.

[Task]
The C / N (Carrier to Noise Ratio) in a satellite broadcast wave used for advanced broadband satellite digital broadcasting is, for example, 16 dB to 18 dB.

Generally, in order to reproduce an advanced broadband satellite digital broadcast, a C / N of 12 dB or more is required in the broadcast wave. For example, when the broadcast wave is attenuated during transmission and the C / N becomes smaller than 12 dB, it is received. It becomes difficult to reproduce the advanced wideband satellite digital broadcasting contained in the broadcast wave.

Further, for example, in order to receive a broadcast wave based on a satellite broadcast wave transmitted via a cable television network at a subscriber's home and reproduce an advanced wideband satellite digital broadcast included in the received broadcast wave, the TMCC information can be used. We need our transmission TMCC information. However, the transmission TMCC information is not output from the tuner 11 as a main signal.

Therefore, in order to transmit a broadcast wave based on a satellite broadcast wave via a cable television network or the like in a broadcast retransmission system, for example, it is necessary to create transmission TMCC information.

However, since the transmission TMCC information is prohibited from being changed, it is necessary to reproduce the transmission TMCC information in the received satellite broadcast wave in the broadcast retransmission system.

Therefore, in the broadcast retransmission system according to the embodiment of the present invention, the above problem is solved by the following configuration and operation.

The broadcast retransmission device 101 can partially read the TMCC information from the storage unit 23 of the tuner 11.

More specifically, the reading unit 12 in the broadcast retransmission device 101 uses, for example, an I2C (Inter-Integrated Circuit) bus to tuner the first information, which is a part of the TMCC information, at a rate lower than that of the demodulated data. Read from the storage unit 23 in 11.

FIG. 6 is a diagram showing an example of a format of transmission TMCC information in the broadcast retransmission device according to the embodiment of the present invention. FIG. 6 shows the format of transmission TMCC information according to the standard of Non-Patent Document 3.

With reference to FIG. 6, the transmission TMCC information includes change instructions, transmission mode / slot information, stream type / relative stream information, packet format / relative stream information, pointer / slot information, relative stream / slot information, in order from the beginning. It consists of fields for relative stream / transmission stream ID correspondence table information, transmission / reception control information, and extended information.

The data length of the change instruction is 8 bits. The data length of the transmission mode / slot information is 192 bits. The data length of the stream type / relative stream information is 128 bits. The data length of the packet format / relative stream information is 896 bits. The pointer / slot information data length is 3840 bits. The data length of the relative stream / slot information is 480 bits. The data length of the relative stream / transmission stream ID correspondence table information is 256 bits. The data length of the transmission / reception control information is 8 bits. The data length of the extended information is 3614 bits.

As the first information, the reading unit 12 sets the values of the change instruction, the transmission mode / slot information, the stream type / relative stream information, the relative stream / slot information, the relative stream / transmission stream ID correspondence table information, and the transmission / reception control information. It is read from the storage unit 23, and each read value is output to the information restoration unit 14.

In this way, the reading unit 12 can acquire the necessary information within 33 milliseconds, which is the length of the frame, by reading 1072 bits of the 9422-bit transmission TMCC information. ..

On the other hand, the information creation unit 13 creates a second piece of information that is included in the transmission TMCC information and is different from the first piece of information.

More specifically, since the pointer / slot information in the transmission TMCC information is different for each frame, it is necessary to set it for each frame.

However, the data length of the pointer / slot information is as large as 3840 bits. Therefore, it is difficult to read the pointer / slot information from the storage unit 23 in a time shorter than 33 milliseconds, which is the length of the frame, using the I2C bus whose communication rate is lower than the rate of the demodulated data.

Further, since it is difficult to read the pointer / slot information in association with the demodulation data, it is difficult to determine which demodulation data the read pointer / slot information corresponds to.

Therefore, the information creation unit 13 creates pointer / slot information in the transmission TMCC information as the second information based on the demodulation data received from the demodulation unit 22.

FIG. 7 is a diagram showing an example of the configuration of pointer / slot information of transmission TMCC information in the broadcast retransmission device according to the embodiment of the present invention. FIG. 7 shows the structure of pointer / slot information according to the standard of Non-Patent Document 3.

With reference to FIG. 7, in the pointer / slot information field of the transmission TMCC information, 16-bit values indicating the top pointer and the last pointer of each slot are sequentially stored.

More specifically, the value of the top pointer is the value of the above-mentioned first TLV instruction in the first TLV packet among the plurality of TLV packets included in each slot.

The value of the last pointer indicates the position at the end of the last TLV packet among the plurality of TLV packets included in each slot, in bytes from the beginning of the field of the main signal.

Specifically, with reference to FIG. 7, the information creation unit 13 acquires the value of the first head TLV instruction in each slot of the demodulation data received from the demodulation unit 22, and obtains the value of the acquired head TLV instruction. Set as the value of the top pointer in the slot.

Further, the information creation unit 13 acquires the value of the last leading TLV instruction included in the main signal field of each slot.

Then, the information creation unit 13 refers to the TLV packet including the acquired head TLV instruction, and acquires the value of the field of "length" in the TLV packet.

The information creation unit 13 calculates the value of the last pointer in each slot based on the acquired value of the head TLV instruction and the value of the “length” field.

The information creation unit 13 sets the value of the top pointer in each set slot and the value of the last pointer in each calculated slot in order as the value of the pointer / slot information field.

The information creation unit 13 outputs the set pointer / slot information value to the information restoration unit 14.

The information restoration unit 14 restores a part or all of the transmission TMCC information by combining the first information read by the reading unit 12 and the second information created by the information creating unit 13.

More specifically, the information restoration unit 14 receives a change instruction from the reading unit 12, transmission mode / slot information, stream type / relative stream information, relative stream / slot information, relative stream / transmission stream ID correspondence table information, and Each value of the transmission / reception control information is arranged according to the format of the transmission TMCC information.

Further, the information restoration unit 14 stores the value of the pointer / slot information received from the information creation unit 13 in the pointer / slot information field of the transmission TMCC information.

Then, the information restoration unit 14 stores the same fixed value as the transmission TMCC information included in the satellite broadcast wave received by the tuner 11 in the packet format / relative stream information field and the extended information field of the transmission TMCC information. All of the transmitted TMCC information is restored, and the restored transmission TMCC information is output to the stream generation unit 15.

The information restoration unit 14 stores fixed values different from the transmission TMCC information included in the satellite broadcast wave received by the tuner 11 in the packet format / relative stream information field and the extension information field of the transmission TMCC information. This may be configured to restore a part of the transmission TMCC information and output the restored transmission TMCC information to the stream generation unit 15.

The stream generation unit 15 generates a stream including the demodulated data received from the tuner 11 and the transmission TMCC information restored by the information restoration unit 14.

More specifically, the stream generation unit 15 generates a stream by adding the transmission TMCC information received from the information restoration unit 14 to the demodulated data received from the tuner 11, and writes the generated stream to the FIFA 31.

Further, the stream generation unit 15 reads out the stream stored in the FIFA 31 and outputs it to the broadcast wave generation unit 16.

Here, the adjusting unit 17 detects the timing of the frame based on the demodulated data received from the tuner 11, and adjusts the frequency of the clock used in the stream generation unit 15 based on the detected timing.

The adjusting unit 17 measures the length of time of the frame included in the demodulated data received from the demodulation unit 22. More specifically, the adjusting unit 17 detects the beginning of a frame in the demodulated data received from the demodulation unit 22.

Specifically, the first TLV packet contained in the frame contains NTP data. When the coordinating unit 17 detects the NTP data, the coordinating unit 17 acquires the transmission stream ID of the TLV packet by referring to the MMT packet in the TLV packet including the detected NTP data.

Then, the adjusting unit 17 uses the MH-SDT (MH-Service Description Table: MH service description table) showing the correspondence relationship between the transmission stream ID included in the MMT packet and the numbers of the plurality of streams included in the frame. Then, it is collated which stream number in the frame corresponds to the acquired transmission stream ID.

When the acquired transmission stream ID is the stream of stream number SN1 in the frame, the adjusting unit 17 determines that the slot header of the slot containing the NTP data in the TLV packet at the head of the stream is the head of the frame. , The number of clock pulses received from the VCO 18 is counted from the slot header.

Then, when the adjusting unit 17 detects the beginning of the next frame, the clock count is stopped and the count value is acquired. Then, the adjusting unit 17 resets the clock count value to zero and restarts the count.

The adjusting unit 17 determines the magnitude of the output voltage to the VCO 18 for adjusting the oscillation frequency of the VCO 18 based on the acquired clock count value.

More specifically, the adjusting unit 17 determines whether or not the frame is longer than 33 milliseconds by counting the clock pulse output by the VCO 18 in 1115520, and adjusts the oscillation frequency of the VCO 18 based on the determination result. Determine the magnitude of the output voltage to the VCO 18 for this purpose.

Specifically, for example, when the count value of the acquired clock is larger than 1115520, the adjusting unit 17 determines the magnitude of the output voltage to the VCO 18 so that the oscillation frequency in the VCO 18 becomes smaller.

Further, for example, when the count value of the acquired clock is smaller than 1115520, the clock adjusting unit 43 determines the magnitude of the output voltage to the VCO 18 so that the oscillation frequency in the VCO 18 becomes large.

Further, the adjusting unit 17 adjusts the oscillation frequency of the VCO 18 based on the amount of data accumulated in the FIFA 31.

More specifically, the stream generation unit 15 uses the clock received from the VCO 18 to read out the stream stored in the FIFA 31. The stream generation unit 15 monitors the amount of data accumulated so that the FIFO 31 does not overflow or underflow, and outputs the monitoring result to the adjustment unit 17.

The amount of data stored in the FIFA 31 is reduced when the frequency of the clock received from the VCO 18 is greater than the frequency of the clock used to write the stream to the FIFA 31, and the frequency of the clock received from the VCO 18 is the frequency of the clock used to write the stream to the FIFA 31. Increases when the frequency is smaller.

The stream generation unit 15 outputs to the adjustment unit 17 a monitoring result indicating that the amount of data accumulated in the FIFA 31 is decreasing, or a monitoring result indicating that the amount of data accumulated in the FIFA 31 is increasing.

The adjusting unit 17 determines the magnitude of the output voltage to the VCO 18 for adjusting the oscillation frequency of the VCO 18 based on the monitoring result received from the stream generation unit 15.

More specifically, when the adjusting unit 17 receives a monitoring result from the stream generation unit 15 indicating that the amount of data accumulated in the FIFA 31 is decreasing, the adjusting unit 17 determines the output voltage to the VCO 18 so that the oscillation frequency in the VCO 18 becomes smaller. Determine the size.

Further, when the adjusting unit 17 receives the monitoring result from the stream generation unit 15 that the amount of data accumulated in the FIFO 31 is increasing, the adjusting unit 17 determines the magnitude of the output voltage to the VCO 18 so that the oscillation frequency in the VCO 18 becomes large. decide.

In this way, the stream generation unit 15 and the adjustment unit 17 monitor the amount of data accumulated in the FIFA 31, and the frequency of the clock received from the VCO 18 and the frequency of the clock used for writing to the FIFO 31 have a predetermined division ratio or a predetermined division ratio. Adjust the frequency of the clock received from VCO18 so that it has the same frequency. As a result, the frequency of the transmission clock of the stream generated by the stream generation unit 15 can be adjusted to the frequency of the transmission clock of the stream included in the satellite broadcast wave.

The VCO 18 outputs a clock having an oscillation frequency according to the magnitude of the voltage received from the adjusting unit 17.

The broadcast wave generation unit 16 modulates the stream generated by the stream generation unit 15 to generate a retransmission credit broadcast wave.

More specifically, the transmission mode / slot information in the transmission TMCC information indicates a stream modulation method or the like. The broadcast wave generation unit 16 uses the clock received from the VCO 18 to perform modulation processing of the stream according to the transmission mode / slot information in the transmission TMCC information included in the stream received from the stream generation unit 15.

Then, the broadcast wave generation unit 16 converts the frequency of the modulated stream into a frequency corresponding to, for example, the cable television network 10 to generate a retransmission credit broadcast wave.

Further, for example, the broadcast wave generation unit 16 uses a clock having a frequency adjusted by the adjustment unit 17.

By adjusting the clock frequency as described above, the adjusting unit 17 adjusts the frequency of the clock used in the broadcast wave generation unit 16 to the frequency of the transmission clock of the stream included in the satellite broadcast wave.

As a result, the broadcast wave generation unit 16 can generate a retransmission credit broadcast wave that follows the timing of the clock having the same frequency as the transmission clock frequency of the stream included in the satellite broadcast wave.

Then, the broadcast wave generation unit 16 transmits the generated retransmitted credit broadcast wave to each subscriber's house 152 via, for example, the cable television network 10.

[Operation flow]
Each device in the broadcast retransmission system 301 includes a computer including a memory, and an arithmetic processing unit such as a CPU in the computer reads a program including a part or all of each step in the following flowchart from the memory and executes the program. do. The programs of these plurality of devices can be installed from the outside. The programs of these plurality of devices are distributed in a state of being stored in a recording medium.

FIG. 8 is a flowchart defining an operation procedure when the broadcast retransmission device according to the embodiment of the present invention generates a retransmitted credit broadcast wave.

With reference to FIG. 8, first, the broadcast retransmission device 101 receives a satellite broadcast wave, generates a stream by demodulating the received satellite broadcast wave, and stores TMCC information in the generated stream. It is stored in 23, and the demodulated data that does not include the TMCC information in the generated stream is output (step S101).

Next, the broadcast retransmission device 101 reads out the first information that is a part of the TMCC information from the storage unit 23 in the tuner 11 (step S102).

Next, the broadcast retransmission device 101 uses the generated demodulation data to create second information that is included in the TMCC information and is different from the first information (step S103).

Next, the broadcast retransmission device 101 restores a part or all of the transmission TMCC information by combining the above-mentioned fixed value, the read first information, and the created second information (step S104).

Next, the broadcast retransmission device 101 adds the restored transmission TMCC information to the generated demodulated data to generate a stream including the restored transmission TMCC information (step S105).

Next, the broadcast retransmission device 101 generates a retransmission credit broadcast wave by modulating the generated stream (step S106).

Next, the broadcast retransmission device 101 transmits the generated retransmission credit broadcast wave to each subscriber's home 152 via, for example, the cable television network 10 (step S107).

The operations of steps S102 and S103 are not limited to the above, and the order may be changed.

Further, in the broadcast retransmission system according to the embodiment of the present invention, the adjusting unit 17 is configured to adjust the clock frequency based on the timing of the frame, but the present invention is not limited to this. The adjusting unit 17 may be configured to adjust the clock frequency based on the timing of slots and the like included in the frame.

In the broadcast retransmission device according to the embodiment of the present invention, the tuner 11 is configured to output demodulated data that does not include TMCC information, but the present invention is not limited to this. The tuner 11 may be configured to output demodulation data including a part of TMCC information. In this case, the tuner 11 has a configuration in which a part of the TMCC information not included in the demodulated data among the TMCC information can be read from the storage unit 23 by the reading unit 12. Further, the tuner 11 may have a configuration in which a part of the TMCC information included in the demodulated data can be read out from the storage unit 23 by the reading unit 12.

By the way, a technology capable of constructing an excellent system for retransmitting advanced broadband satellite digital broadcasting to a subscriber's home via a network such as a cable television network is desired.

On the other hand, in the broadcast retransmission device according to the embodiment of the present invention, the tuner 11 receives and demodulates satellite broadcast waves including program information and TMCC information, and outputs demodulated data including program information. , TMCC information not included in the demodulated data can be partially read from the storage unit 23. The reading unit 12 reads the first information, which is a part of the TMCC information, from the storage unit 23 of the tuner 11. The information creation unit 13 creates a second piece of information that is included in the TMCC information and is different from the first piece of information. The information restoration unit 14 restores a part or all of the TMCC information by combining the first information read by the reading unit 12 and the second information created by the information creating unit 13. The stream generation unit 15 generates a stream including the demodulated data received from the tuner 11 and the TMCC information restored by the information restoration unit 14. The broadcast wave generation unit 16 modulates the stream generated by the stream generation unit 15 to generate a retransmission credit broadcast wave.

In this way, the TMCC information is restored by reading a part of the TMCC information from the tuner 11 and further creating the TMCC information excluding the read part by itself to restore the TMCC information included in the received satellite broadcast wave. It is possible to retransmit satellite broadcast waves using a tuner that does not output at least part of. Further, by remodulating the demodulated data output from the tuner 11, the carrier-to-noise ratio can be made larger than that of the original satellite broadcast wave. Therefore, for example, in the subscriber's house 152, via the broadcast retransmission device 101. It is possible to receive the transmitted broadcast wave and stably play back the program included in the received broadcast wave.

Therefore, in the broadcast retransmission device according to the embodiment of the present invention, it is possible to construct an excellent system for retransmitting an advanced wideband satellite digital broadcast to a subscriber's home via a network such as a cable television network.

Further, in the broadcast retransmission device according to the embodiment of the present invention, the satellite broadcast wave includes a plurality of frames. The adjusting unit 17 detects the timing of the frame based on the demodulated data received from the tuner 11, and adjusts the frequency of the clock used in the stream generation unit 15 and the broadcast wave generation unit 16 based on the detected timing.

With such a configuration, the frequency of the clock of the retransmitted credit broadcast wave can be adjusted to the frequency of the transmission clock of the satellite broadcast wave by a simple process.

Further, in the broadcast retransmission method according to the embodiment of the present invention, first, the first information which is a part of the TMCC information is read from the storage unit 23 of the tuner 11. Next, the second information, which is the information included in the TMCC information and is different from the first information, is created. Next, a part or all of the TMCC information is restored by combining the read first information and the created second information. Next, a stream containing the demodulated data received from the tuner 11 and the restored TMCC information is generated. Next, the generated stream is modulated to generate a retransmission credit broadcast wave.

In this way, the TMCC information is restored by reading a part of the TMCC information from the tuner 11 and further creating the TMCC information excluding the read part by itself to restore the TMCC information included in the received satellite broadcast wave. It is possible to retransmit satellite broadcast waves using a tuner that does not output at least part of. Further, by remodulating the demodulated data output from the tuner 11, the carrier-to-noise ratio can be made larger than that of the original satellite broadcast wave. Therefore, for example, in the subscriber's house 152, via the broadcast retransmission device 101. It is possible to receive the transmitted broadcast wave and stably play back the program included in the received broadcast wave.

Therefore, in the broadcast retransmission method according to the embodiment of the present invention, it is possible to construct an excellent system for retransmitting an advanced wideband satellite digital broadcast to a subscriber's home via a network such as a cable television network.

It should be considered that the above embodiments are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

The above description includes the features described below.
[Appendix 1]
A broadcast retransmission device used for advanced wideband satellite digital broadcasting.
With a tuner that receives and demodulates satellite broadcast waves including program information and TMCC information, outputs demodulated data including the program information, and can partially read the TMCC information not included in the demodulated data from the storage unit. ,
A reading unit that reads out first information that is a part of the TMCC information from the storage unit of the tuner.
An information creation unit that creates a second piece of information that is included in the TMCC information and is different from the first piece of information.
An information restoration unit that restores a part or all of the TMCC information by combining the first information read by the reading unit and the second information created by the information creation unit.
A stream generation unit that generates a stream containing the demodulated data received from the tuner and the TMCC information restored by the information restoration unit.
It is provided with a broadcast wave generation unit that modulates the stream generated by the stream generation unit to generate a retransmission credit broadcast wave.
The broadcast wave generation unit generates the retransmission credit broadcast wave based on the first information acquired by the acquisition unit.
The reading unit reads the first information from the storage unit of the tuner at a rate lower than that of the demodulated data.
The adjusting unit is a broadcast retransmission device that tunes the frequency of the clock used in the broadcast wave generation unit to the frequency of the transmission clock of the stream included in the satellite broadcast wave.

10 Cable TV network 11 Tuner 12 Read unit 13 Information creation unit 14 Information restoration unit 15 Stream generation unit 16 Broadcast wave generation unit 17 Adjustment unit 18 VCO
21 Receiver 22 Demodulation 23 Storage 31 FIFO
81 External antenna 101 Broadcast retransmission device 131 STB
133 TV monitor 151 Station building 152 Subscriber home 301 Broadcast retransmission system

Claims (3)

A broadcast retransmission device used for advanced wideband satellite digital broadcasting.
With a tuner that receives and demodulates satellite broadcast waves including program information and TMCC information, outputs demodulated data including the program information, and can partially read the TMCC information not included in the demodulated data from the storage unit. ,
A reading unit that reads out first information that is a part of the TMCC information from the storage unit of the tuner.
An information creation unit that creates a second piece of information that is included in the TMCC information and is different from the first piece of information.
An information restoration unit that restores a part or all of the TMCC information by combining the first information read by the reading unit and the second information created by the information creation unit.
A stream generation unit that generates a stream containing the demodulated data received from the tuner and the TMCC information restored by the information restoration unit.
A broadcast retransmission device including a broadcast wave generation unit that modulates the stream generated by the stream generation unit to generate a retransmission credit broadcast wave. The satellite broadcast wave includes a plurality of frames and contains a plurality of frames.
The broadcast retransmission device further
It includes an adjustment unit that detects the timing of the frame based on the demodulation data received from the tuner and adjusts the frequency of the clock used in the stream generation unit and the broadcast wave generation unit based on the detected timing. , The broadcast retransmission device according to claim 1. Used for advanced broadband satellite digital broadcasting, it receives and demolishes satellite broadcast waves including program information and TMCC information, outputs demographic data including the program information, and stores the TMCC information not included in the demographic data. It is a broadcast retransmission method in a broadcast retransmission device provided with a tuner that can be partially read from a unit.
A step of reading the first information which is a part of the TMCC information from the storage unit of the tuner, and
A step of creating a second piece of information that is included in the TMCC information and is different from the first piece of information.
A step of restoring a part or all of the TMCC information by combining the read-out first information and the created second information.
A step of generating a stream containing the demodulated data received from the tuner and the restored TMCC information.
A broadcast retransmission method comprising the step of modulating the generated stream to generate a retransmitted credit broadcast wave.

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