JP2020010109A - Broadcasting re-transmission device and broadcasting re-transmission method - Google Patents

Abstract

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

Description

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

  2. Description of the Related Art Conventionally, a technology for transmitting content using an MMTP (MPEG Media Transport Protocol) packet has been developed.

  For example, the Radio Industry Association of Japan, “Media Transport System Using MMT in Digital Broadcasting ARIB STD-B60 1.9 Edition”, March 24, 2017 (Non-Patent Document 1), a broadcast using the MMT system. A system is disclosed.

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

The Association of Radio Industries and Businesses, "Media Transport Method with MMT for Digital Broadcasting ARIB STD-B60 1.9 Edition", March 24, 2017 International Telecommunications Union Radiocommunications Sector, "Recommendation ITU-R BT.1869", March 2010, [online], [Search August 29, 2017], Internet <URL: // 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 System for Advanced Broadband Satellite Digital Broadcasting ARIB STD-B44 2.1 Version", March 25, 2016

  For example, an advanced broadband according to the method disclosed in “Transmission system of advanced broadband satellite digital broadcasting ARIB STD-B44 2.1 version”, Radio Broadcasting Industry Association of Japan, March 25, 2016 (Non-Patent Document 3). There is a demand for 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 television network.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object 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 an object of the present invention to provide a broadcast retransmission device and a broadcast retransmission method capable of performing the above.

  (1) In order to solve the above problem, a broadcast retransmitting device according to an aspect of the present invention is a broadcast retransmitting device used for advanced broadband satellite digital broadcasting, and includes a satellite broadcast including program information and TMCC information. A tuner that demodulates the wave and outputs demodulated data including the information of the program, and the TMCC information not included in the demodulated data is partially read from a storage unit; A reading unit that reads first information that is a part of information; an information creating unit that creates second information that is included in the TMCC information and that is different from the first information; By combining the first information read by the reading unit and the second information created by the information creating unit, a part of the TMCC information or An information restoration unit for restoring the whole, a stream generation unit for generating a stream including the demodulated data received from the tuner, and the TMCC information restored by the information restoration unit, and a stream generation unit for generating a stream including the TMCC information. A broadcast wave generation unit that modulates the stream to generate a broadcast wave for retransmission.

  (3) In order to solve the above problem, a broadcast retransmission method according to an aspect of the present invention is used for advanced broadband satellite digital broadcasting, receives and demodulates a satellite broadcast wave including program information and TMCC information, A broadcast retransmission method in a broadcast retransmission device including a tuner that outputs demodulated data including information of the program, and the TMCC information not included in the demodulated data is partially read from a storage unit. Reading first information that is part of the TMCC information from the storage unit, and creating second information that is included in the TMCC information and that is different from the first information Restoring part or all of the TMCC information by combining the read first information and the created second information; The demodulated data received from the tuner, and generating a stream including restored the TMCC information, and generating a re-transmission broadcast wave by modulating the generated the stream.

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

  ADVANTAGE OF THE INVENTION According to this invention, the outstanding system which retransmits an advanced broadband satellite digital broadcast to a subscriber's house via networks, such as a cable television network, can be constructed.

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 illustrating an example of a protocol stack of data transmitted by a satellite broadcast wave 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 the 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 stream frame 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 illustrating an example of a 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 that defines an operation procedure when the broadcast retransmission device according to the embodiment of the present invention generates a retransmission broadcast wave.

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

  (1) A broadcast retransmitting device according to an embodiment of the present invention is a broadcast retransmitting device used for advanced broadband satellite digital broadcasting, and receives and demodulates a satellite broadcast wave including program information and TMCC information. A tuner that outputs demodulated data including the information of the program, and the TMCC information not included in the demodulated data is a tuner that can be partially read from a storage unit, and a tuner that is a part of the TMCC information from the storage unit of the tuner. A reading unit that reads out the first information, an information creating unit that creates second information that is information included in the TMCC information and that is different from the first information, and that is read out by the reading unit. An information restoring unit that restores a part or all of the TMCC information by combining the first information and the second information created by the information creating unit; A stream generation unit that generates a stream including the demodulated data received from the tuner and the TMCC information restored by the information restoration unit; and a broadcast wave for retransmission by modulating the stream generated by the stream generation unit. And a broadcast wave generation unit that generates

  As described above, by reading a part of the TMCC information from the tuner, and further creating the TMCC information excluding the read part by itself, the TMCC information included in the received satellite broadcast wave is restored, so that the A satellite broadcast wave can be retransmitted using a tuner that does not output at least a portion. Also, 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. Broadcast waves can be received, and a program included in the received broadcast waves can be stably reproduced. Therefore, it is possible to construct an excellent system for retransmitting the advanced broadband satellite digital broadcast 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 retransmitting device further detects a timing of the frame based on the demodulated data received from the tuner, and detects the detected timing. And an adjustment unit that adjusts the frequency of a clock used in the stream generation unit and the broadcast wave generation unit based on the

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

  (3) The broadcast retransmission method according to the embodiment of the present invention is used for advanced broadband satellite digital broadcasting, receives and demodulates a satellite broadcast wave containing program information and TMCC information, and demodulates the program including the program information. A broadcast retransmission method in a broadcast retransmission device including a tuner that outputs data and the TMCC information not included in the demodulated data is partially read from a storage unit, wherein the TMCC information is stored in the storage unit of the tuner. Reading the first information that is a part of the first information, creating the second information that is included in the TMCC information and that is different from the first information, And restoring a part or all of the TMCC information by combining the information and the created second information; and Including adjustment data, and generating a stream including restored the TMCC information, and generating a re-transmission broadcast wave by modulating the generated the stream.

  As described above, by reading a part of the TMCC information from the tuner, and further creating the TMCC information excluding the read part by itself, the TMCC information included in the received satellite broadcast wave is restored, so that the A satellite broadcast wave can be retransmitted using a tuner that does not output at least a portion. Also, 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. Broadcast waves can be received, and a program included in the received broadcast waves can be stably reproduced. Therefore, it is possible to construct an excellent system for retransmitting the advanced broadband satellite digital broadcast 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. In the drawings, the same or corresponding portions have the same reference characters allotted, and description thereof will not be repeated. Further, at least some 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.

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

  Note that the broadcast retransmission system 301 is not limited to a configuration including a plurality of STBs 131, and may be a configuration including one STB 131.

  Broadcast retransmitting apparatus 101 is provided, for example, in station 151 of a company that provides cable television broadcasting. STB 131 and TV monitor 133 are provided in subscriber house 152.

  An external antenna 81 is connected to the broadcast retransmission device 101, for example. Broadcast retransmitting apparatus 101 receives a satellite broadcast wave including a stream, for example.

  The stream includes 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 information and the video information are compressed and encrypted, for example, according to a predetermined method.

  Broadcast retransmitting apparatus 101 receives, via external antenna 81, a satellite broadcast wave transmitted from a broadcasting satellite (not shown) for advanced broadband satellite digital broadcasting, for example, for relaying a stream from a broadcasting station.

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

  Referring to FIG. 2, the TLV packet is often used for transmission of 4K UHDTV (Ultra High Definition Television) or 8K UHDTV or the like according to a standard such as 2160p or 4320p.

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

  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 in which information indicating the data type is stored. The International Telecommunication Union Radio Communications Sector, “Recommendation ITU-R BT. 1869”, March 2010, [online], [Heisei 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. pdf> (Non-Patent Document 2) shows the format of a TLV packet.

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

  A value such as “0x01”, “0x02”, “0x03”, or “0xFF” is stored in the “packet type” field. Here, a number starting with “0x” means that the numbers after “0x” are represented in hexadecimal.

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

  When “0x02” is stored in the “packet type” field, the TLV packet 62 includes, in the TLV payload, an IPv6 packet having the total data length of the value stored in the “length” field.

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

  When “0xFF” is stored in the “packet type” field, the TLV packet 64 includes null data that is the total data length of the value stored in the “length” field in the TLV payload. Hereinafter, a TLV packet including null data in a TLV payload is also referred to as a TLV null packet.

  Referring to FIG. 2 again, for example, NTP (Network Time Protocol) data for time synchronization, IP-SI data, time information, an MMT packet, or a data transmission method is stored in a UDP (User Datagram Protocol) / IP packet. Is 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.

  Referring to FIG. 1 again, broadcast retransmitting apparatus 101 acquires program information from satellite broadcast waves, and transmits a broadcast wave including the acquired program information to each subscriber home 152 via cable television network 10. I do.

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

  When receiving the broadcast wave from the broadcast retransmitting apparatus 101, the STB 131 acquires program information from the received broadcast wave, decodes audio information and video information based on the acquired program information, and decodes the decoded audio information. And the video information is transmitted to the TV monitor 133.

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

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

  Referring to FIG. 4, broadcast retransmitting apparatus 101 includes a tuner 11, a reading unit 12, an information creating unit 13, an information restoring unit 14, a stream generating unit 15, a broadcast wave generating unit 16, an adjusting unit 17 and a VCO (Voltage-Controlled Oscillator) 18. The tuner 11 includes a reception unit 21, a demodulation unit 22, and a storage unit 23. The stream generation unit 15 includes a FIFO 31.

  The VCO 18 generates a reference clock. More specifically, the VCO 18 can generate a clock having a frequency corresponding to the magnitude of the voltage received from the adjustment unit 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 including TMCC information.

  More specifically, the receiving unit 21 of the tuner 11 receives via the external antenna 81 a satellite broadcast wave including program information and TMCC information transmitted from a broadcast satellite for advanced broadband satellite digital broadcast, and receives the received satellite broadcast. The wave is output to the demodulation unit 22.

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

  The demodulation unit 22 acquires a stream included in a 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 a TLV program packet and time alignment information based on the digital signal, and stores the TMCC information in the generated stream in the storage unit 23.

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

  It is specified 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.

  A frame can include a plurality of streams respectively corresponding to programs of up to 16 broadcast stations. Each stream is distinguished by using a transmission stream ID included in an MMT packet in a TLV packet, for example.

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

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

  Referring to FIG. 5, a frame includes 120 slots. That is, for example, 40 slots are allocated to one stream. For example, the stream of stream number SN1 is assigned slots 1 to 40, 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.

  A stream is divided and stored in the slot. The length of the frame is 33 milliseconds.

  Each slot includes 44880-bit demodulated data and 1600-bit TMCC information in order from the beginning.

  Demodulated data is composed of a slot header, a main signal, a BCH code parity, a stuff bit, and an LDPC (Low Density Parity Check) code parity field in order from the top.

  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 main signal field.

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

  The head TLV indication 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 the 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 variable.

  The TMCC information includes a field of basic 280-bit fixed-length TMCC information and a field of 1320-bit fixed-length transmission TMCC information and the like in order from the top.

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

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

  31680-bit information obtained by adding 192 bits of BCH code parity and 22066 bits of LDPC code parity to 9422 bits of transmission TMCC information obtained by adding 9240 bits of 1320 bits × 7 slots and 182 bits of the eighth slot is 24 bits. Stored across slots.

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

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

  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 house and reproduce an advanced broadband satellite digital broadcast included in the received broadcast wave, it is necessary to use TMCC information. The transmission TMCC information is required. However, the transmission TMCC information is not output from the tuner 11 as a main signal.

  For this reason, in the broadcast retransmission system, transmission of a broadcast wave based on a satellite broadcast wave via a cable television network or the like requires, for example, creation of transmission TMCC information.

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

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

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

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

  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 a format of transmission TMCC information according to the standard of Non-Patent Document 3.

  Referring to FIG. 6, transmission TMCC information includes, in order from the beginning, a change instruction, transmission mode / slot information, stream type / relative stream information, packet format / relative stream information, pointer / slot information, relative stream / slot information, It is composed of relative stream / transmission stream ID correspondence table information, transmission / reception control information, and extension information fields.

  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 extension information is 3614 bits.

  The reading unit 12 stores, as the first information, 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. The information is read from the storage unit 23 and the read values are output to the information restoring unit 14.

  As described above, by reading out 1072 bits of the 9422-bit transmission TMCC information, the reading unit 12 can acquire necessary information during the frame time length of 33 milliseconds. .

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

  More specifically, since the pointer / slot information in the transmission TMCC information differs for each frame, it must be set 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 the frame time length of 33 milliseconds using the I2C bus whose communication rate is lower than the demodulated data rate.

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

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

  FIG. 7 is a diagram illustrating an example of a 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 a configuration of pointer / slot information according to the standard of Non-Patent Document 3.

  Referring 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-described 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 of the end of the last TLV packet among the plurality of TLV packets included in each slot by the number of bytes from the head of the field of the main signal.

  Specifically, referring to FIG. 7, information creating section 13 obtains the value of the first head TLV instruction in each slot of the demodulated data received from demodulation section 22, and stores the obtained value of the head TLV instruction in each slot. Set as the value of the top pointer in the slot.

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

  Then, the information creating unit 13 acquires the value of the “length” field in the TLV packet with reference to the TLV packet including the acquired leading TLV instruction.

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

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

  The information creating unit 13 outputs the value of the set pointer / slot information to the information restoring unit 14.

  The information restoring unit 14 restores 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 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 received from the reading unit 12, and The values of the transmission / reception control information are arranged in accordance with the format of the transmission TMCC information.

  The information restoring unit 14 stores the value of the pointer / slot information received from the information creating unit 13 in the pointer / slot information field of the transmission TMCC information.

  Then, the information restoring 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 extension information field of the transmission TMCC information. Thus, all the transmission TMCC information is restored, and the restored transmission TMCC information is output to the stream generation unit 15.

  The information restoring unit 14 stores a fixed value 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. Thus, the transmission TMCC information may be partially restored and the restored transmission TMCC information may be output 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 FIFO 31.

  Further, the stream generator 15 reads the stream stored in the FIFO 31 and outputs the stream to the broadcast wave generator 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 generating unit 15 based on the detected timing.

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

  Specifically, the first TLV packet included in the frame includes NTP data. When detecting the NTP data, the adjusting 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 an MH-SDT (MH-Service Description Table: MH service description table) indicating the correspondence between the transmission stream ID included in the MMT packet and the numbers of a plurality of streams included in the frame. Then, it is checked whether the acquired transmission stream ID corresponds to which stream number in the frame.

  When the acquired transmission stream ID is the stream of the stream number SN1 in the frame, the adjustment unit 17 determines that the slot header of the slot including the NTP data in the TLV packet at the head of the stream is the head of the frame. , VCO 18 from the slot header.

  Then, when detecting the head of the next frame, the adjusting unit 17 stops counting the clock and acquires the count value. Then, the adjusting unit 17 resets the count value of the clock 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 adjustment unit 17 determines whether or not the frame is longer than 33 milliseconds by counting the number of pulses of the clock output from the VCO 18 by 1115520, and adjusts the oscillation frequency of the VCO 18 based on the determination result. The magnitude of the output voltage to the VCO 18 is determined.

  Specifically, for example, when the acquired clock count value is greater than 1115520, adjustment unit 17 determines the magnitude of the output voltage to VCO 18 such that the oscillation frequency of VCO 18 decreases.

  For example, when the acquired clock count value is smaller than 1115520, the clock adjustment unit 43 determines the magnitude of the output voltage to the VCO 18 so that the oscillation frequency of the VCO 18 increases.

  The adjusting unit 17 adjusts the oscillation frequency of the VCO 18 based on the amount of data stored in the FIFO 31.

  More specifically, the stream generator 15 reads the stream stored in the FIFO 31 using the clock received from the VCO 18. The stream generation unit 15 monitors the amount of accumulated data 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 FIFO 31 decreases when the frequency of the clock received from the VCO 18 is higher than the frequency of the clock used to write the stream to the FIFO 31, and the frequency of the clock received from the VCO 18 becomes smaller than the frequency of the clock used to write the stream to the FIFO 31. Increases when the frequency is smaller than the frequency.

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

  The adjustment 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 receiving a monitoring result indicating that the amount of accumulated data in the FIFO 31 is decreasing from the stream generating unit 15, the adjusting unit 17 adjusts the output voltage to the VCO 18 so that the oscillation frequency in the VCO 18 decreases. Determine the size.

  In addition, when receiving a monitoring result indicating that the amount of stored data in the FIFO 31 is increasing from the stream generation unit 15, the adjustment unit 17 adjusts the magnitude of the output voltage to the VCO 18 so that the oscillation frequency of the VCO 18 increases. decide.

  As described above, the stream generation unit 15 and the adjustment unit 17 monitor the amount of data stored in the FIFO 31 and determine whether the frequency of the clock received from the VCO 18 and the frequency of the clock used for writing to the FIFO 31 are equal to the predetermined frequency division ratio or The frequency of the clock received from the VCO 18 is adjusted so as to have the same frequency. Accordingly, 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 adjustment unit 17.

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

  More specifically, the transmission mode / slot information in the transmission TMCC information indicates a stream modulation method and the like. Using the clock received from the VCO 18, the broadcast wave generator 16 performs a modulation process on the stream according to the transmission mode / slot information in the transmission TMCC information included in the stream received from the stream generator 15.

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

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

  The adjustment 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 by adjusting the clock frequency as described above.

  Thereby, the broadcast wave generation unit 16 can generate a retransmission broadcast wave according to the timing of the clock having the same frequency as the frequency of the transmission clock of the stream included in the satellite broadcast wave.

  Then, the broadcast wave generation unit 16 transmits the generated retransmission broadcast wave to each subscriber home 152 via, for example, the cable television network 10.

[Flow of operation]
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 out and executes a program including some or all of the steps in the flowchart below from the memory. I do. Each of the programs of the plurality of devices can be externally installed. The programs of the plurality of devices are distributed while being stored in a recording medium.

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

  Referring to FIG. 8, first, broadcast retransmitting apparatus 101 receives a satellite broadcast wave, generates a stream by demodulating the received satellite broadcast wave, and stores TMCC information in the generated stream in a storage unit. 23, and outputs demodulated data that does not include TMCC information in the generated stream (step S101).

  Next, the broadcast retransmitting 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, using the generated demodulated data, broadcast retransmitting apparatus 101 creates second information that is information included in the TMCC information and that is different from the first information (step S103).

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

  Next, the broadcast retransmitting apparatus 101 generates a stream including the restored transmission TMCC information by adding the restored transmission TMCC information to the generated demodulated data (step S105).

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

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

  The operations of step S102 and step 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, adjustment unit 17 is configured to adjust the frequency of the clock 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 frequency of the clock based on the timing of a slot or the like included in the frame.

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

  By the way, there is a demand for a technology capable of constructing 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.

  On the other hand, in the broadcast retransmitting apparatus according to the embodiment of the present invention, tuner 11 receives and demodulates a satellite broadcast wave including program information and TMCC information, and outputs demodulated data including program information. The 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 that is a part of the TMCC information from the storage unit 23 of the tuner 11. The information creating unit 13 creates second information that is information included in the TMCC information and that is different from the first information. The information restoring unit 14 restores 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 broadcast wave.

  As described above, by reading a part of the TMCC information from the tuner 11 and further creating the TMCC information excluding the read part by itself, the TMCC information included in the received satellite broadcast wave is restored, so that the TMCC information is restored. Can be retransmitted using a tuner that does not output at least a portion 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. The transmitted broadcast wave can be received, and the program included in the received broadcast wave can be stably reproduced.

  Therefore, the broadcast retransmitting apparatus according to the embodiment of the present invention can 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.

  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 generating unit 15 and the broadcast wave generating unit 16 based on the detected timing.

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

  In the broadcast retransmission method according to the embodiment of the present invention, first, the first information that is a part of the TMCC information is read from the storage unit 23 of the tuner 11. Next, second information that is included in the TMCC information and that 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 including 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 broadcast wave.

  As described above, by reading a part of the TMCC information from the tuner 11 and further creating the TMCC information excluding the read part by itself, the TMCC information included in the received satellite broadcast wave is restored, so that the TMCC information is restored. Can be retransmitted using a tuner that does not output at least a 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. The transmitted broadcast wave is received, and the program included in the received broadcast wave can be stably reproduced.

  Therefore, with the broadcast retransmission method according to the embodiment of 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.

  The above embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

The above description includes the features described below.
[Appendix 1]
A broadcast retransmitting device used for advanced broadband satellite digital broadcasting,
A tuner which receives and demodulates a satellite broadcast wave including program information and TMCC information, outputs demodulated data including the program information, and wherein the TMCC information not included in the demodulated data can be partially read from a storage unit. ,
A reading unit that reads first information that is a part of the TMCC information from the storage unit of the tuner;
An information creation unit that creates second information that is information included in the TMCC information and that is different from the first information;
An information restoration unit that restores 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 including the demodulated data received from the tuner, and the TMCC information restored by the information restoration unit;
A broadcast wave generation unit that modulates the stream generated by the stream generation unit to generate a broadcast wave for retransmission,
The broadcast wave generation unit generates the retransmission 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 lower rate than the demodulated data,
The broadcast retransmission device, wherein the adjustment unit adjusts a frequency of a clock used in the broadcast wave generation unit to a frequency of a transmission clock of a stream included in the satellite broadcast wave.

Reference Signs List 10 Cable TV network 11 Tuner 12 Readout unit 13 Information creation unit 14 Information restoration unit 15 Stream generation unit 16 Broadcast wave generation unit 17 Adjustment unit 18 VCO
DESCRIPTION OF SYMBOLS 21 Receiving part 22 Demodulation part 23 Storage part 31 FIFO
81 external antenna 101 broadcast retransmission device 131 STB
133 TV monitor 151 Station building 152 Subscriber house 301 Broadcast retransmission system

Claims (3)

A broadcast retransmitting device used for advanced broadband satellite digital broadcasting,
A tuner which receives and demodulates a satellite broadcast wave including program information and TMCC information, outputs demodulated data including the program information, and wherein the TMCC information not included in the demodulated data can be partially read from a storage unit. ,
A reading unit that reads first information that is a part of the TMCC information from the storage unit of the tuner;
An information creation unit that creates second information that is information included in the TMCC information and that is different from the first information;
An information restoration unit that restores 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 including the demodulated data received from the tuner, and the TMCC information restored by the information restoration unit;
A broadcast retransmission device, comprising: a broadcast wave generation unit that modulates the stream generated by the stream generation unit to generate a retransmission broadcast wave. The satellite broadcast wave includes a plurality of frames,
The broadcast retransmission device further includes:
An adjusting unit that detects a timing of the frame based on the demodulated data received from the tuner, and adjusts a frequency of a clock used in the stream generation unit and the broadcast wave generation unit based on the detected timing. The broadcast retransmitting device according to claim 1. Used for advanced broadband satellite digital broadcasting, receives and demodulates satellite broadcast waves including program information and TMCC information, outputs demodulated data including the program information, and stores the TMCC information not included in the demodulated data. A broadcast retransmission method in a broadcast retransmission device including a tuner that can be partially read from a unit,
Reading first information that is a part of the TMCC information from the storage unit of the tuner;
Creating second information that is information included in the TMCC information and that is different from the first information;
Restoring part or all of the TMCC information by combining the read first information and the created second information;
Generating a stream containing the demodulated data received from the tuner, and the reconstructed TMCC information;
Modulating the generated stream to generate a retransmission broadcast wave.

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