JP7302713B2 - Broadcast retransmission device, broadcast retransmission system and broadcast retransmission method - Google Patents

Description

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

Conventionally, technology has been developed for transmitting content using MMTP (MPEG Media Transport Protocol) packets.

For example, the Association of Radio Industries and Businesses, "Media transport method by MMT in digital broadcasting ARIB STD-B60 Version 1.9", March 24, 2017 (Non-Patent Document 1), broadcasting using the MMT method A system is disclosed.

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

Association of Radio Industries and Businesses, “Media transport method by MMT in digital broadcasting ARIB STD-B60 Version 1.9”, March 24, 2017 International Telecommunication Union Radiocommunications Sector, ``Recommendation ITU-R BT. 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 broadband satellite digital broadcasting ARIB STD-B44 Version 2.1", March 25, 2016

General Incorporated Association of Radio Industries and Businesses, "Transmission method for advanced broadband satellite digital broadcasting ARIB STD-B44 Version 2.1", advanced broadband satellite digital according to the method disclosed on March 25, 2016 (non-patent document 3) There is a demand for a technology capable of constructing an excellent system for retransmitting broadcast waves, such as broadcast waves, to subscribers' homes via a network.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a broadcast retransmitting apparatus and a broadcast retransmitting apparatus capable of constructing an excellent system for retransmitting broadcast waves to subscribers' homes via a network. It is to provide a retransmission method.

(1) In order to solve the above problems, a broadcast retransmission device according to one aspect of the present invention is a broadcast retransmission device that receives broadcast waves including one or more streams that form a frame, a stream generation unit for generating the stream included in the broadcast wave and storing it in a buffer; reading the stream generated by the stream generation unit from the buffer; modulating the read stream to retransmit the broadcast wave; a broadcast wave generation unit that generates a clock included in the broadcast wave based on the timing detected by the detection unit that detects the timing of the frame included in the received broadcast wave; a clock reproducing unit that reproduces and corrects the frequency of the clock based on the accumulated amount of the buffer, wherein the clock reproduced by the clock reproducing unit is the broadcast wave generating unit including the readout of the stream. Used for processing.

(5) In order to solve the above problems, a broadcast retransmission device according to an aspect of the present invention receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, and a tuner for outputting demodulated data including part or all of the IP broadcast wave, which is a broadcast wave including IP packets, obtaining a stream included in the IP packets, and generating frames from the obtained stream an IP communication unit that outputs; a stream generation unit that can select the output of the stream; a broadcast wave generation unit that modulates the stream received from the stream generation unit to generate a retransmission broadcast wave; a clock reproducing unit that reproduces the included clock and can select a reproduction source, and the selected target of the output by the stream generating unit is the demodulated data generated by the stream generating unit and received from the tuner. There are an output of the stream including part or all of it and an output of the stream included in the frame received from the IP communication unit, and the clock reproduced by the clock reproduction unit is the broadcast wave generation unit. , and the reproduction source of the clock reproduction unit includes the demodulated data received from the tuner and the frame received from the IP communication unit.

(9) In order to solve the above problems, a broadcast retransmission system according to one aspect of the present invention includes a first broadcast retransmission device and a second broadcast retransmission device, wherein the first broadcast retransmission device A transmitting device receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, generates the stream partly or wholly contained in the demodulated data, and transmits the generated stream. and transmits the IP broadcast wave, which is the broadcast wave including the generated IP packet, to the IP network, and the second broadcast retransmitting device receives the satellite broadcast wave, which is the broadcast wave including the frame. to generate a stream including part or all of the demodulated data, and the second broadcast retransmitting device receives the IP broadcast wave via the IP network, and receives the IP broadcast wave from the received IP broadcast wave. Acquiring the stream, the second broadcast retransmitting device can select a retransmitting broadcast wave to be transmitted to a subscriber network, and the second broadcast retransmitting device selects the retransmitting broadcast wave is a retransmission broadcast wave obtained by modulating the stream generated from the satellite broadcast wave, and a retransmission broadcast wave obtained by modulating the stream obtained from the IP broadcast wave.

(10) In order to solve the above problems, a broadcast retransmission method according to an aspect of the present invention is a broadcast retransmission method in a broadcast retransmission device, comprising: a broadcast wave including one or more streams forming a frame; generating the stream included in the received broadcast wave and storing it in a buffer; detecting timing of the frame included in the received broadcast wave; correcting the frequency of the clock based on the amount of accumulation in the buffer; reading the generated stream from the buffer; and modulating the read stream. and generating a broadcast wave for retransmission by using the reproduced clock for processing including reading of the stream in the step of generating the broadcast wave for retransmission.

(11) In order to solve the above problems, a broadcast retransmission method according to an aspect of the present invention is a broadcast retransmission method in a broadcast retransmission device, comprising: a broadcast wave including one or more streams forming a frame; a step of receiving and demodulating a satellite broadcast wave and outputting demodulated data including part or all of the frame; and generating and outputting a frame from the obtained stream; selecting the output of the stream; selecting a reproduction source and reproducing the clock included in the broadcast wave; using a clock to modulate the output stream to generate a broadcast wave for retransmission, wherein the selection target in the step of selecting the output includes part or all of the output demodulated data. The output of the generated stream and the output of the stream included in the output frame are included in the stream, and the output source includes the output demodulated data and the output frame.

(12) In order to solve the above problems, a broadcast retransmission method according to one aspect of the present invention provides broadcast retransmission in a broadcast retransmission system including a first broadcast retransmission device and a second broadcast retransmission device. In the transmission method, the first broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, to generate the stream included in the demodulated data. generating IP packets containing the generated stream and transmitting IP broadcast waves, which are broadcast waves containing the generated IP packets, to an IP network; a step of receiving and demodulating a satellite broadcast wave, which is a wave, to generate a stream including part or all of the demodulated data; and obtaining a stream from the received IP broadcast wave; and the second broadcast retransmission device selecting a retransmission broadcast wave to be transmitted to the subscriber network, The retransmission broadcast waves selected by the broadcast retransmission device include retransmission broadcast waves obtained by modulating the stream generated from the satellite broadcast waves, and retransmission broadcast waves obtained by modulating the stream obtained from the IP broadcast waves. There is.

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

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

According to the present invention, an excellent system for retransmitting broadcast waves to subscribers' homes via a network can be constructed.

FIG. 1 is a diagram showing the configuration of a broadcast retransmission system according to the first embodiment of the invention. FIG. 2 is a diagram showing an example protocol stack of data transmitted by broadcast waves in the broadcast retransmission system according to the first embodiment of the present invention. FIG. 3 is a diagram showing an example of TLV packets transmitted by broadcast waves in the broadcast retransmission system according to the first embodiment of the present invention. FIG. 4 is a diagram showing the configuration of a broadcast retransmission device in the broadcast retransmission system according to the first 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 first embodiment of the present invention. FIG. 6 is a diagram showing changes in buffer accumulation amount in the broadcast retransmitting apparatus according to the first embodiment of the present invention. FIG. 7 is a flow chart defining an operation procedure when the broadcast retransmission apparatus according to the first embodiment of the present invention performs broadcast retransmission. FIG. 8 is a flow chart defining an operation procedure when the broadcast retransmitting apparatus according to the first embodiment of the present invention adjusts the clock frequency. FIG. 9 is a diagram showing the configuration of a broadcast retransmission system according to the second embodiment of the invention. FIG. 10 is a diagram showing the configuration of a broadcast retransmission device in a broadcast retransmission system according to the second embodiment of the present invention. FIG. 11 is a diagram showing an example of IP packet format in the broadcast retransmission system according to the second embodiment of the present invention. FIG. 12 is a flow chart defining an operation procedure when the broadcast retransmitting apparatus according to the second embodiment of the present invention performs broadcast retransmission.

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

(1) A broadcast retransmission device according to an embodiment of the present invention is a broadcast retransmission device that receives a broadcast wave including one or more streams that form a frame, and is included in the received broadcast wave A stream generation unit that generates the stream and stores it in a buffer, and a broadcast wave generation unit that reads the stream generated by the stream generation unit from the buffer and modulates the read stream to generate a retransmission broadcast wave. a detection unit for detecting the timing of the frame included in the received broadcast wave; a clock included in the broadcast wave based on the timing detected by the detection unit; A clock reproducing unit that corrects the frequency of the clock based on the accumulated amount, and the clock reproduced by the clock reproducing unit is used for processing of the broadcast wave generating unit including reading of the stream.

With such a configuration, in reproducing the clock of the broadcast wave, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the broadcast wave by simple processing based on the timing of the frame. Further, the clock frequency of the broadcast wave can be reproduced more accurately by the configuration in which the frequency of the clock is corrected by paying attention to the accumulated amount of the buffer. Then, by re-modulating the demodulated data output from the tuner, the carrier-to-noise ratio can be made larger than that of the original satellite broadcast wave. To stably reproduce a program included in a broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

(2) Preferably, the broadcast retransmitting device further receives and demodulates the satellite broadcast wave, which is the broadcast wave, and outputs demodulated data including part or all of the frame included in the satellite broadcast wave. A tuner is provided, the stream generation unit generates the stream partly or wholly included in the demodulated data received from the tuner, and the detection unit generates the stream based on the demodulated data received from the tuner Detect frame timing.

With such a configuration, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the satellite broadcast wave.

(3) Preferably, the broadcast retransmission device further reads the stream generated by the stream generation unit from the buffer, generates IP packets containing the read stream, and generates IP packets for retransmission containing the IP packets. It has an IP communication unit that transmits broadcast waves to an IP network.

With such a configuration, it is possible to transmit the broadcast wave for retransmission via the IP network, so that, for example, even in areas where it is difficult to receive satellite broadcast waves, it is possible to reproduce programs included in satellite broadcast waves.

(4) Preferably, the broadcast retransmitting device further receives IP broadcast waves, which are the broadcast waves containing IP packets, via an IP network, acquires the stream included in the received IP packets, and acquires an IP communication unit for generating and outputting a frame from the stream received from the IP communication unit, the stream generating unit storing the stream included in the frame received from the IP communication unit in a buffer; The timing of the frame is detected based on the frame received from the communication unit.

With such a configuration, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the IP broadcast wave by simple processing based on the frame timing of the IP broadcast wave.

(5) A broadcast retransmission apparatus according to an embodiment of the present invention receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, and includes part or all of the frame. a tuner that outputs demodulated data; an IP communication unit that receives an IP broadcast wave that is a broadcast wave including IP packets, acquires a stream included in the IP packets, generates and outputs frames from the acquired stream; a stream generation unit capable of selecting the output of the stream; a broadcast wave generation unit for modulating the stream received from the stream generation unit to generate a retransmission broadcast wave; reproducing a clock included in the broadcast wave; a clock reproducing unit capable of selecting a reproduction source, and the output selected by the stream generating unit includes part or all of the demodulated data generated by the stream generating unit and received from the tuner. There are the output of the stream and the output of the stream included in the frame received from the IP communication unit, and the clock reproduced by the clock reproduction unit is used in the broadcast wave generation unit to reproduce the clock. The reproduction source of the unit includes the demodulated data received from the tuner and the frame received from the IP communication unit.

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

(6) Preferably, the stream generator selects the output according to communication quality of the satellite broadcast wave and communication quality of the IP broadcast wave.

With such a configuration, it is possible to select and output broadcast waves with better communication quality, so that services such as program distribution can be provided more stably.

(7) Preferably, the broadcast retransmitting device further includes a tuner that receives and demodulates the satellite broadcast wave, which is the broadcast wave, and outputs demodulated data including part or all of the frame,
The stream generation unit generates the stream for part or all of the demodulated data received from the tuner, and the retransmission broadcast wave is the satellite broadcast received by the tuner in the broadcast retransmission device itself or in another broadcast retransmission device. The clock contained in the wave contains the recovered clock.

With such a configuration, by matching the clock frequency of the retransmission broadcast wave to the clock frequency of the broadcast wave received via the network from another broadcast retransmission device, the clock frequency of the retransmission broadcast wave can be set to It is possible to match the frequency of the transmission clock of the satellite broadcast wave received by another broadcast retransmission device. That is, it is possible to transmit the clock frequency of the satellite broadcast wave via the network and retransmit the satellite broadcast wave received by another broadcast retransmitting device to the subscriber's house.

(8) Preferably, the broadcast waves are broadcast waves of advanced wideband satellite digital broadcasting.

With such a configuration, the clock frequency of the broadcast wave for retransmission can be matched with the frequency of the transmission clock used in the broadcast wave of the advanced wideband satellite digital broadcasting.

(9) A broadcast retransmission system according to an embodiment of the present invention includes a first broadcast retransmission device and a second broadcast retransmission device, and the first broadcast retransmission device configures a frame. receive and demodulate a satellite broadcast wave, which is a broadcast wave containing one or more streams, generate the stream partly or wholly contained in the demodulated data, generate an IP packet containing the generated stream, The IP broadcast wave, which is a broadcast wave including the generated IP packet, is transmitted to the IP network, and the second broadcast retransmitting device receives and demodulates the satellite broadcast wave, which is a broadcast wave including the frame, and converts it into demodulated data. The second broadcast retransmission device receives the IP broadcast wave via the IP network, acquires the stream from the received IP broadcast wave, and The second broadcast retransmitting device is capable of selecting a retransmitting broadcast wave to be transmitted to a subscriber network. There are a retransmission broadcast wave obtained by modulating the generated stream and a retransmission broadcast wave obtained by modulating the stream obtained from the IP broadcast wave.

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

(10) A broadcast retransmission method according to an embodiment of the present invention is a broadcast retransmission method in a broadcast retransmission device, comprising: receiving a broadcast wave including one or more streams forming a frame; a step of generating the stream included in the received broadcast wave and storing it in a buffer; a step of detecting timing of the frame included in the received broadcast wave; regenerating the clock contained in the clock; correcting the frequency of the clock based on the accumulated amount of the buffer; reading out the generated stream from the buffer; wherein the regenerated clock is used for processing including reading of the stream in the step of generating the broadcast wave for retransmission.

With such a configuration, in reproducing the clock of the broadcast wave, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the broadcast wave by simple processing based on the timing of the frame. Further, the clock frequency of the broadcast wave can be reproduced more accurately by the configuration in which the frequency of the clock is corrected by paying attention to the accumulated amount of the buffer. Then, by re-modulating the demodulated data output from the tuner, the carrier-to-noise ratio can be made larger than that of the original satellite broadcast wave. To stably reproduce a program included in a broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

(11) A broadcast retransmission method according to an embodiment of the present invention is a broadcast retransmission method in a broadcast retransmission device, in which a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, is received. and outputting demodulated data including part or all of the frame; receiving an IP broadcast wave that is a broadcast wave including IP packets, obtaining a stream included in the IP packets, a step of selecting the output of the stream; a step of selecting a reproduction source and reproducing the clock contained in the broadcast wave; and modulating the stream to generate a broadcast wave for retransmission, wherein an object to be selected in the step of selecting the output is the stream partly or wholly included in the output demodulated data. There are the output of the stream and the output of the stream included in the output frame, and the playback source includes the output demodulated data and the output frame.

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

(12) A broadcast retransmission method according to an embodiment of the present invention is a broadcast retransmission method in a broadcast retransmission system including a first broadcast retransmission device and a second broadcast retransmission device, A first broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, generates the stream included in the demodulated data, and transmits the generated stream. a step of generating an IP packet containing the frame and transmitting the IP broadcast wave, which is a broadcast wave containing the generated IP packet, to an IP network; a step of receiving and demodulating to generate a stream including part or all of the demodulated data; obtaining a stream from an IP broadcast wave; and selecting a retransmission broadcast wave to be transmitted to a subscriber network by the second broadcast retransmission device, wherein the retransmission by the second broadcast retransmission device Retransmission broadcast waves obtained by modulating the stream generated from the satellite broadcast waves and retransmission broadcast waves obtained by modulating the stream obtained from the IP broadcast waves are selected as the trusted broadcast waves.

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave. Therefore, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated. Moreover, at least part of the embodiments described below may be combined arbitrarily.

<First Embodiment>
FIG. 1 is a diagram showing the configuration of a broadcast retransmission system according to the first embodiment of the invention.

Referring to FIG. 1 , broadcast retransmission system 301 includes broadcast retransmission device 101 , subscriber network 10 and a plurality of STBs (Set Top Boxes) 131 . STB 131 is connected to 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 configured to include one STB 131. FIG.

Broadcast retransmitting device 101 is installed, for example, in station building 151 of an operator that provides cable television broadcasting. STB 131 and TV monitor 133 are provided in subscriber's home 152 .

For example, an external antenna 81 is connected to the broadcast retransmitting device 101 . Broadcast retransmitting device 101 receives broadcast waves including streams, for example.

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

Audio information and video information are, for example, compressed and encrypted according to a predetermined method.

Broadcast retransmitting device 101 receives, via external antenna 81, satellite broadcast waves, which are broadcast waves transmitted from a broadcasting satellite for advanced wideband satellite digital broadcasting (not shown) for relaying streams from broadcasting stations, for example. .

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

Referring to FIG. 2, TLV packets are often used for transmission of 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 broadcast wave includes, for example, TMCC (Transmission & Multiplexing Configuration Control) information, AC information and TLV packets.

FIG. 3 is a diagram showing an example of TLV packets transmitted by broadcast waves in the broadcast retransmission system according to the first embodiment of the present invention. FIG. 3 shows an example of a packet having a header storing information indicating a data type, International Telecommunication Union Radiocommunications Sector, ``Recommendation ITU-R BT.1869'', March 2010, [online], [Heisei Retrieved 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).

A TLV packet includes a TLV header and a TLV payload. The TLV header includes a 'start code' field with a value of '01', a 'future reserved' 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, the numbers starting with "0x" mean 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 whose total data length is 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 an IPv6 packet whose total data length is the value stored in the "length" field in the TLV payload.

When "0x03" is stored in the "packet type" field, the TLV packet 63 includes an IP packet whose total data length is the value stored in the "length" field in the TLV payload. A compressed IP packet is, for example, an IP packet whose 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 containing null data in the 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, MMT packets, or data transmission methods are stored in UDP (User Datagram Protocol)/IP packets. be done. MMT packets contain video information, audio information, MMT-SI data, and other information.

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 broadcast waves, and transmits the broadcast waves including the acquired program information to each subscriber's home 152 via subscriber network 10. .

STB 131 receives, for example, broadcast waves transmitted from broadcast retransmitting device 101 via subscriber network 10 .

Upon receiving the broadcast wave from the broadcast retransmitting device 101, the STB 131 acquires program information from the received broadcast wave, decodes the audio information and video information based on the acquired program information, and outputs the decoded audio information. and video information to the TV monitor 133 .

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

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

[Broadcast retransmission device]
4, broadcast retransmitting apparatus 101 includes tuner 11, stream generator 15, broadcast wave generator 16, clock reproducer 17, VCO (Voltage-Controlled Oscillator) 18, and detector 19. and Stream generator 15 includes buffer 31 .

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 clock recovery section 17 within a predetermined frequency range including 33.7571 megahertz.

[Generate Stream]
For example, tuner 11 receives and demodulates satellite broadcast waves, and outputs demodulated data including part or all of the frames included in the satellite broadcast waves.

More specifically, the tuner 11 receives satellite broadcast waves including program information transmitted from a broadcasting satellite for advanced wideband satellite digital broadcasting via the external antenna 81, and transmits a stream included in the received satellite broadcast waves. get.

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

Specifically, the tuner 11 demodulates the received satellite broadcasting wave and converts it into a digital signal. Then, the tuner 11 generates demodulated data including part or all of the TLV program packet, time adjustment information, and TMCC information based on the digital signal, and sends the generated demodulated data to the stream generation unit 15 and the detection unit. 19.

Tuner 11 also outputs a clock corresponding to the demodulated data to stream generator 15, for example.

Note that the tuner 11 may store part or all of the acquired stream in the storage unit 21, for example.

Tuner 11 also measures, for example, the level and carrier to noise ratio (C/N) of the received satellite broadcast wave, and outputs the measurement results to stream generation section 15 and to storage section 21. save.

It is stipulated that a satellite broadcast wave includes one or more streams forming a frame. Multiple streams can be efficiently transmitted by using satellite broadcast waves to transmit streams while maintaining the frame structure.

A frame can contain multiple streams, each corresponding to a program from up to 16 stations. Each stream is distinguished, for example, by using the transport stream ID contained in the MMT packet in the TLV packet.

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

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

Referring to FIG. 5, a frame consists of 120 slots. For example, 40 slots are assigned to one stream. For example, slots 1 to 40 are assigned to the stream of stream number SN1, slots 41 to 80 are assigned to the stream of stream number SN2, and slots 81 to 120 are assigned to the stream of stream number SN3. assigned.

Streams are divided and stored in slots. Also, the time length of the frame is 33 milliseconds.

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

The demodulated data consists of fields of slot header, main signal, BCH code parity, stuff bit and LDPC (Low Density Parity Check) code parity in 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 more divided TLV packets or the like are stored in the main signal field.

If the demodulated data contains a TLV packet, the first 16 bits of the slot header indicate a leading TLV indication.

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 stuff bits is 6 bits. The data length of the LDPC code parity is variable.

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

The basic TMCC information field includes, in order from the top, a 120-bit fixed-length synchronization signal field and a 160-bit fixed-length field of constellation information.

TMCC information is divided and stored in a plurality of slots. More specifically, the synchronization signal is stored over 24 slots. Signal point arrangement information is stored over 24 to 120 slots according to the combination of modulation schemes.

In addition, 31680-bit information obtained by adding 192 bits of BCH code parity and 22066 bits of LDPC code parity to 9422-bit transmission TMCC information obtained by adding 9240 bits of 1320 bits x 7 slots and 182 bits of the 8th slot is 24 Stored across slots.

Referring to FIG. 4 again, stream generator 15 generates a stream included in the received broadcast wave and stores it in buffer 31 .

For example, the stream generation unit 15 generates a stream including part or all of the demodulated data received from the tuner 11 .

More specifically, for example, when stream generator 15 receives demodulated data including part of a frame from tuner 11, such as demodulated data not including TMCC information, stream generator 15 holds the demodulated data.

Then, the stream generation unit 15 reads, for example, part of the data of the stream saved by the tuner 11 from the storage unit 21 in the tuner 11, and combines the read part of the data with the held demodulated data to obtain , to generate a stream.

The stream generator 15 writes the generated stream to the buffer 31 . The buffer 31 is, for example, a FIFO (First In First Out).

The stream generation unit 15 uses, for example, the clock included in the broadcast wave, that is, the clock received from the tuner 11, to generate a symbol rate of 33.7561 Mbaud, that is, 1115520 symbols per 33 milliseconds according to the modulation scheme of the TMCC information included in the frame. Write to the buffer 31 at the corresponding bit rate.

Alternatively, for example, when the stream generation unit 15 receives demodulated data including all frames, that is, the entire stream from the tuner 11 , the stream is written to the buffer 31 .

[Clock adjustment]
The detector 19 detects the timing of frames included in the received broadcast wave. For example, the detector 19 detects the frame timing based on the demodulated data received from the tuner 11 .

More specifically, the detector 19 measures the length of time of the frame included in the demodulated data received from the tuner 11 . Specifically, the detector 19 detects the head timing of the frame in the demodulated data received from the tuner 11 .

The first TLV packet included in the frame contains NTP data. Upon detecting the NTP data, the detection unit 19 acquires the transmission stream ID of the TLV packet by referring to the MMT packet in the TLV packet containing the detected NTP data.

Then, the detection unit 19 uses an MH-SDT (MH-Service Description Table) that indicates the correspondence relationship between the transmission stream IDs included in the MMT packet and the numbers of a plurality of streams included in the frame. to check which stream number in the frame the acquired transmission stream ID corresponds to.

When the acquired transmission stream ID is the stream of stream number SN1 in the frame, the detection unit 19 determines that the slot header of the slot containing the NTP data in the TLV packet at the beginning of the stream is the beginning of the frame, Information TI 1 indicating the timing of the head of the frame is output to the clock reproducing unit 17 .

The clock reproducing unit 17 reproduces the clock contained in the broadcast wave based on the frame timing detected by the detecting unit 19 .

More specifically, the clock recovery unit 17 receives the information TI1 from the detection unit 19 and starts counting pulses of the clock received from the VCO 18 .

When receiving the next information TI1 from the detection unit 19, the clock recovery unit 17 stops counting and holds the current count value. Then, the clock recovery unit 17 resets the count value to zero and restarts counting.

The clock recovery 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 held count value.

More specifically, the clock recovery unit 17 counts 1,115,520 clock pulses output from the VCO 18 to determine whether the frame is longer than 33 milliseconds, 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 to adjust.

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

For example, when the acquired clock count value is smaller than 1115520, the clock recovery unit 17 determines the magnitude of the output voltage to the VCO 18 so that the oscillation frequency of the VCO 18 increases.

Note that the clock recovery unit 17 may count clock pulses until the information TI1 is received a plurality of times, and adjust the oscillation frequency of the VCO 18 based on the count value.

The VCO 18 outputs a clock with a frequency corresponding to the magnitude of the voltage received from the clock recovery section 17 .

The broadcast wave generator 16 uses the clock reproduced by the clock reproducer 17 to read the stream generated by the stream generator 15 from the buffer 31 .

More specifically, the broadcast wave generator 16 uses the clock received from the VCO 18 to read the stream accumulated in the buffer 31 .

At this time, the amount of data accumulated in the buffer 31 decreases when the frequency of the clock received from the VCO 18 is greater than the frequency of the clock used for writing the stream to the buffer 31, and increases when it is smaller than the frequency of the clock used for writing.

Therefore, the clock recovery unit 17 corrects the clock frequency based on the accumulated amount of the buffer 31 .

More specifically, the clock recovery unit 17 monitors the amount of data accumulated in the buffer 31 so that the buffer 31 does not overflow or underflow.

FIG. 6 is a diagram showing changes in buffer accumulation amount in the broadcast retransmitting apparatus according to the first embodiment of the present invention. In FIG. 6, the horizontal axis indicates time, and the vertical axis indicates the buffer accumulation amount.

Referring to FIG. 6, broadcast wave generation unit 16 starts reading out the stream at time t0 when the amount of data accumulated in buffer 31 exceeds reference value L0, specifically, the amount of stream accumulated for three frames. Start.

The clock recovery unit 17 acquires the amount of data accumulated in the buffer 31, for example, each time it receives the information TI1 from the detection unit 19 3000 times.

Next, at time t1 when the information TI1 is received 3000 times, for example, if the acquired accumulated amount is greater than a predetermined upper limit value L1, the clock recovery unit 17 outputs the output voltage to the VCO 18 so that the oscillation frequency of the VCO 18 increases. determine the size of

As a result, the frequency of the clock received from the VCO 18 becomes higher than the frequency of the clock used for writing the stream to the buffer 31, so the amount of data accumulated in the buffer 31 is reduced.

Next, at time t2 when the information TI1 is received 6000 times, if the acquired accumulation amount is smaller than the predetermined lower limit value L2, the clock recovery unit 17 increases the output voltage to the VCO 18 so that the oscillation frequency of the VCO 18 becomes small. determine the

As a result, the frequency of the clock received from the VCO 18 becomes lower than the frequency of the clock used for writing the stream to the buffer 31, so the amount of data accumulated in the buffer 31 increases.

The clock reproducing unit 17 reproduces the clock contained in the broadcast wave by adjusting the frequency of the clock as described above.

Note that the clock recovery unit 17 is not limited to the configuration in which the clock frequency is corrected by monitoring the accumulated amount of data based on the predetermined upper limit value L1 or the predetermined lower limit value L2. The clock frequency may be corrected by monitoring the accumulated amount of data based on an increase or decrease in the accumulated amount.

More specifically, for example, when the accumulated amount obtained at time t2 is greater than the accumulated amount obtained at time t1, clock recovery unit 17 increases the magnitude of the output voltage to VCO 18 so that the oscillation frequency of VCO 18 increases. to decide.

On the other hand, when the accumulated amount obtained at time t2 is smaller than the accumulated amount obtained at time t1, the clock recovery unit 17 determines the magnitude of the output voltage to the VCO 18 so that the oscillation frequency of the VCO 18 becomes small.

[Generation of broadcast waves for retransmission]
The broadcast wave generation unit 16 modulates the stream read from the buffer 31 to generate retransmission broadcast waves.

More specifically, the broadcast wave generation unit 16 uses the clock received from the VCO 18, that is, the clock reproduced by the clock reproduction unit 17, for example, according to the transmission TMCC information included in the stream read from the buffer 31, to reproduce the stream. modulation processing.

Then, the broadcast wave generation unit 16 converts the frequency of the modulated stream to, for example, a frequency corresponding to the subscriber network 10 and generates a retransmission broadcast wave.

Thereby, the broadcast wave generator 16 can generate a retransmission broadcast wave according to the timing of the clock having the same frequency as that of the clock included in the broadcast wave.

Then, the broadcast wave generator 16 transmits the generated retransmission broadcast wave to each subscriber's home 152 via the subscriber network 10, for example.

[Flow of operation]
Each device in the broadcast retransmission system 301 has a computer including a memory, and an arithmetic processing unit such as a CPU in the computer reads and executes a program including part or all of each step in the following flowchart from the memory. do. Programs for these multiple devices can each be installed from the outside. Programs for these devices are stored in recording media and distributed.

FIG. 7 is a flow chart defining an operation procedure when the broadcast retransmission apparatus according to the first embodiment of the present invention performs broadcast retransmission.

Referring to FIG. 7, first, broadcast retransmitting apparatus 101 receives and demodulates a broadcast wave including one or more streams forming a frame to generate demodulated data including part or all of the frame ( step S101).

Next, broadcast retransmitting apparatus 101 generates a stream partially or wholly included in the generated demodulated data (step S102).

Next, the broadcast retransmitting device 101 accumulates the generated stream in the buffer 31 (step S103).

Next, the broadcast retransmitting device 101 detects the timing of the frame included in the received broadcast wave (step S104).

Next, the broadcast retransmitting device 101 reproduces the clock contained in the broadcast wave based on the detected timing (step S105).

Further, the broadcast retransmitting device 101 corrects the clock frequency based on the accumulated amount of the buffer 31 (step S106).

Next, the broadcast retransmitting device 101 uses the reproduced clock to read the generated stream from the buffer 31 (step S107).

Next, the broadcast retransmitting device 101 modulates the read stream to generate retransmitting broadcast waves (step S108).

In addition, step S103 and step S104 are not limited to the above, and the order may be changed, or the steps may be performed in parallel.

FIG. 8 is a flow chart defining an operation procedure when the broadcast retransmitting apparatus according to the first embodiment of the present invention adjusts the clock frequency. FIG. 8 shows details of steps S108 and S115 in FIG.

Referring to FIG. 8, first, when clock reproducing unit 17 in broadcast retransmitting device 101 receives information TI1 indicating the timing of the beginning of a frame included in the satellite broadcast wave received by tuner 11 from detecting unit 19 ( YES at step S201), the length of the frame is measured by counting the pulses of the clock received from the VCO 18 (step S202).

Next, when the clock pulse for the predetermined number of frames has been counted (YES in step S203), the clock recovery unit 17 calculates the difference D1 between the count value and 1115520×the predetermined number of frames (step S204).

Next, the clock recovery unit 17 acquires the amount of data accumulated in the buffer 31 (step S205).

If the accumulated amount is less than the lower limit value L2 (YES in step S206), the clock recovery unit 17 calculates a correction amount M1 for reducing the oscillation frequency of the VCO 18 (step S207), and uses the calculated difference D1 and correction The magnitude of the output voltage to the VCO 18 is determined according to the quantity M1 (step S208).

On the other hand, if the accumulated amount is equal to or greater than the lower limit value L2 (NO at step S206) and equal to or less than the upper limit value L1 (YES at step S209), the clock recovery unit 17 outputs the amount to the VCO 18 according to the calculated difference D1. Determine the magnitude of the output voltage (step S210).

On the other hand, if the accumulated amount is greater than the upper limit value L1 (NO in step S209), the clock recovery unit 17 calculates a correction amount M2 for increasing the oscillation frequency of the VCO 18 (step S211), and calculates the calculated difference d1 and The magnitude of the output voltage to the VCO 18 is determined according to the correction amount M2 (step S212).

On the other hand, if the number of frames for which clock pulses are counted is less than the predetermined number (NO in step S203), the clock recovery unit 17 calculates the difference D1 as zero (step S213), and acquires the amount of data accumulated in the buffer 31. (step S205).

By the way, there is a demand for a technique capable of constructing an excellent system for retransmitting broadcast waves such as advanced broadband satellite digital broadcasting to subscribers' homes via a network.

Therefore, in the broadcast retransmitting apparatus according to the first embodiment of the present invention, stream generator 15 generates a stream included in broadcast waves received by tuner 11 and stores it in buffer 31 . The broadcast wave generator 16 reads the stream generated by the stream generator 15 from the buffer 31 and modulates the read stream to generate a retransmission broadcast wave. The detector 19 detects the timing of frames included in the broadcast waves received by the tuner 11 . The clock reproducing unit 17 reproduces the clock contained in the broadcast wave based on the timing detected by the detecting unit 19 and corrects the frequency of the clock based on the accumulated amount of the buffer 31 . The clock reproduced by the clock reproducing unit 17 is used for the processing of the broadcast wave generating unit 16 including reading of the stream.

With such a configuration, in reproducing the clock of the broadcast wave, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the broadcast wave by simple processing based on the timing of the frame. Further, by correcting the frequency of the clock by paying attention to the accumulated amount of the buffer 31, the clock of the broadcast wave can be reproduced more accurately. 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. It is possible to stably reproduce the program included in the broadcast wave.

Therefore, with the broadcast retransmitting apparatus according to the first embodiment of the present invention, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

Further, in the broadcast retransmitting apparatus according to the first embodiment of the present invention, the tuner receives and demodulates the satellite broadcast waves, which are broadcast waves, and includes part or all of the frames included in the satellite broadcast waves. Output demodulated data. The stream generator 15 generates a stream partly or wholly included in the demodulated data received from the tuner 11 . The detector 19 detects the frame timing based on the demodulated data received from the tuner 11 .

With such a configuration, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the satellite broadcast wave.

Further, in the broadcast retransmitting apparatus according to the first embodiment of the present invention, the broadcast waves are broadcast waves of advanced wideband satellite digital broadcasting.

With such a configuration, the clock frequency of the broadcast wave for retransmission can be matched with the frequency of the transmission clock used in the broadcast wave of the advanced wideband satellite digital broadcasting.

Also, in the broadcast retransmission method according to the first embodiment of the present invention, first, broadcast waves including one or more streams forming a frame are received. Next, a stream included in the received broadcast wave is generated and stored in the buffer 31 . Next, the timing of the frame included in the received broadcast wave is detected. Next, the clock included in the broadcast wave is reproduced based on the detected timing. Next, the clock frequency is corrected based on the accumulated amount of the buffer 31 . Next, the generated stream is read from the buffer 31, and the read stream is modulated to generate a retransmission broadcast wave. In generating broadcast waves for retransmission, the reproduced clock is used to perform processing including reading of the stream.

With such a configuration, in reproducing the clock of the broadcast wave, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the broadcast wave by simple processing based on the timing of the frame. Further, by correcting the frequency of the clock by paying attention to the accumulated amount of the buffer 31, the clock of the broadcast wave can be reproduced more accurately. 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. It is possible to stably reproduce the program included in the broadcast wave.

Therefore, with the broadcast retransmission method according to the first embodiment of the present invention, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

Next, another embodiment of the present invention will be described with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

<Second Embodiment>
Compared with the broadcast retransmission system according to the first embodiment, the present embodiment further relates to a broadcast retransmission system that performs communication via an IP network. The contents other than those described below are the same as those of the broadcast retransmission system according to the first embodiment.

FIG. 9 is a diagram showing the configuration of a broadcast retransmission system according to the second embodiment of the invention.

Referring to FIG. 9 , broadcast retransmission system 302 includes broadcast retransmission device 102A, broadcast retransmission device 102B, and multiple STBs 131 . STB 131 is connected to TV monitor 133 . Hereinafter, each of broadcast retransmitting device 102A and broadcast retransmitting device 102B is also referred to as broadcast retransmitting device 102. FIG.

Note that the broadcast retransmission system 302 is not limited to having a configuration including a plurality of STBs 131, and may have a configuration including one STB 131. FIG.

Broadcast retransmitting device 102A and broadcast retransmitting device 102B are provided, for example, in station building 151 of an operator who provides cable television broadcasting. STB 131 and TV monitor 133 are provided in subscriber's home 152 .

For example, an external antenna 81 is connected to the broadcast retransmitting device 102A and the broadcast retransmitting device 102B. Broadcast retransmitting device 102A, for example, receives satellite broadcast waves, which are broadcast waves including one or more streams forming a frame, via external antenna 81, demodulates them, and converts the stream partly or wholly included in the demodulated data. to generate

Then, broadcast retransmitting device 102A generates IP packets containing the generated stream, and transmits IP broadcast waves, which are broadcast waves containing the generated IP packets, to IP network 20 .

Broadcast retransmitting device 102B receives satellite broadcast waves, which are broadcast waves including frames, via antenna 81 and demodulates them to generate a stream partly or wholly included in the demodulated data.

Also, the broadcast retransmitting device 102B receives the IP broadcast waves transmitted from the broadcast retransmitting device 102A via the IP network 20, and acquires a stream from the received IP broadcast waves.

The broadcast retransmitting device 102B can select retransmitting broadcast waves to be transmitted to the subscriber network 10 . For example, retransmission broadcast waves selected by the broadcast retransmitting device 102B include retransmission broadcast waves obtained by modulating a stream generated from satellite broadcast waves and retransmission broadcast waves obtained by modulating a stream obtained from IP broadcast waves. be.

More specifically, the broadcast retransmitting device 102B modulates a stream generated from satellite broadcast waves according to the communication quality of the satellite broadcast waves and the communication quality of the IP broadcast waves, and transmits to the subscriber network 10 broadcast waves for retransmission. or to transmit to the subscriber network 10 the broadcast wave for retransmission obtained by modulating the stream obtained from the IP broadcast wave.

FIG. 10 is a diagram showing the configuration of a broadcast retransmission device in a broadcast retransmission system according to the second embodiment of the present invention.

Referring to FIG. 10, broadcast retransmitting apparatus 102 further includes IP communication section 12 compared to broadcast retransmitting apparatus 101 shown in FIG. Stream generator 15 further includes buffer 32 .

[Generation of IP broadcast waves]
For example, the IP communication unit 12 in the broadcast retransmitting device 102A reads the stream generated by the stream generation unit 15 from the buffer 31 and generates IP packets containing the read stream.

FIG. 11 is a diagram showing an example of IP packet format in the broadcast retransmission system according to the second embodiment of the present invention.

Referring to FIG. 11, an IP packet is composed of an IP (Internet Protocol) header, a UDP (User Datagram Protocol) header, an RTP (Real-time Transport Protocol) header and payload fields in this order from the top.

Also, IP communication section 12 in broadcast retransmitting device 102A obtains measurement results such as satellite broadcast wave level and C/N corresponding to the stream read from buffer 31 from storage section 21 in tuner 11, for example.

The IP communication unit 12, for example, divides the read stream, stores the divided stream (hereinafter also referred to as a divided stream) and the obtained measurement result in the payload, and adds an IP header, a UDP header and an RTP header. generate a plurality of IP packets with

The IP communication unit 12 then transmits to the IP network 20 a retransmission broadcast wave including each generated IP packet.

9 and 10 again, IP communication unit 12 in broadcast retransmitting device 102A generates a retransmission broadcast wave including each generated IP packet, and transmits the generated retransmission broadcast wave via IP network 20. to the broadcast retransmitting device 102B.

IP communication unit 12 in broadcast retransmitting device 102B receives, via IP network 20, for example, a retransmitting broadcast wave transmitted from broadcast retransmitting device 102A, that is, an IP broadcast wave including each IP packet.

Then, the IP communication unit 12 obtains a stream included in each received IP packet, generates a frame from the obtained stream, and outputs the frame.

More specifically, the IP communication unit 12 acquires segmented streams and corresponding measurement results from IP packets included in received IP broadcast waves, for example.

Then, IP communication section 12 generates a stream by, for example, combining the acquired plurality of divided streams, generates frames from the generated stream, and outputs the frames to stream generation section 15 and detection section 19 . Also, the IP communication unit 12 outputs the acquired corresponding measurement result to the stream generation unit 15 .

For example, detection unit 19 in broadcast retransmitting device 102B detects frame timing based on frames received from IP communication unit 12 .

More specifically, the detection unit 19 measures the time length of the stream, ie, the frame, received from the IP communication unit 12 as described above. Specifically, the detection unit 19 detects the timing of the beginning of the frame received from the IP communication unit 12 and outputs information TI2 indicating the detected timing of the beginning of the frame to the clock reproduction unit 17 .

Based on the information TI2 received from the detector 19, the clock reproducer 17 reproduces the clock contained in the IP broadcast wave.

For example, stream generating section 15 in broadcast retransmitting device 102B outputs the stream included in the frame received from IP communication section 12 to broadcast wave generating section 16 .

More specifically, the stream generation unit 15 receives frames from the IP communication unit 12 and writes streams included in the frames into the buffer 32, for example.

The stream generation unit 15 can select stream output. For example, selection targets for output by the stream generation unit 15 include the output of the stream generated by the stream generation unit 15 and part or all of which is included in the demodulated data received from the tuner 11, and the frame received from the IP communication unit 12. and the output of the stream contained in the .

That is, the stream generation unit 15 switches between generating and outputting a stream partially or wholly included in the demodulated data received from the tuner 11 and outputting the stream included in the frame received from the IP communication unit 12. .

For example, the stream generator 15 selects an output according to the communication quality of satellite broadcast waves and the communication quality of IP broadcast waves.

As an example, when the tuner 11 cannot receive satellite broadcast waves via the external antenna 81 , it outputs reception state information indicating that reception is impossible to the stream generator 15 .

The stream generation unit 15 receives the reception status information indicating that reception is not possible from the tuner 11, does not output the stream from the tuner 11 to the broadcast wave generation unit 16, and transmits the stream from the IP communication unit 12 to the broadcast wave generation unit 16. Output.

As another example, when IP communication unit 12 cannot communicate with another device via IP network 20, IP communication unit 12 outputs information indicating that communication is impossible to stream generation unit 15. FIG.

Stream generation unit 15 receives information indicating that communication is not possible from IP communication unit 12, does not output the stream from IP communication unit 12 to broadcast wave generation unit 16, and transmits the stream from tuner 11 to broadcast wave generation unit 16. Output.

Also, the stream generator 15 compares the measurement result received from the tuner 11 and the measurement result received from the IP communication unit 12, for example, and outputs a stream with better communication quality to the broadcast wave generator 16. do.

Specifically, for example, the stream generation unit 15 determines that the C/N included in the measurement result received from the tuner 11 is better than the C/N included in the measurement result received from the IP communication unit 12. If it is a value, the stream from the IP communication unit 12 is not output to the broadcast wave generation unit 16 and the stream from the tuner 11 is output to the broadcast wave generation unit 16 .

For example, when the level included in the measurement result received from IP communication unit 12 is better than the level included in the measurement result received from tuner 11, that is, when stream generation unit 15 has a larger value, stream generation unit 15 The stream from the IP communication unit 12 is output to the broadcast wave generation unit 16 without outputting the stream from the IP communication unit 12 to the broadcast wave generation unit 16 .

Stream generation unit 15 outputs selection information indicating whether the stream from tuner 11 or the stream from IP communication unit 12 is being output to broadcast wave generation unit 16 and clock reproduction unit 17 .

The clock recovery unit 17 can select a clock recovery source. For example, the clock recovery unit 17 can reproduce the demodulated data received from the tuner 11 and the frame received from the IP communication unit 12 .

Clock reproducing unit 17 reproduces the clock based on the demodulated data received from tuner 11 according to the selection of the output by stream generating unit 15, for example, according to the communication quality of satellite broadcast waves and the communication quality of IP broadcast waves. or reproduce the clock based on the frame received from the IP communication unit 12 .

More specifically, the clock recovery unit 17 recovers the clock based on the information TI1 received from the detection unit 19, or the information TI2 received from the detection unit 19, based on the selection information received from the stream generation unit 15. Toggle whether to play the clock based on

Specifically, for example, when receiving selection information indicating that the stream from tuner 11 is being output from stream generating unit 15, clock reproducing unit 17 reproduces the clock of the demodulated data, that is, the satellite broadcast, based on information TI1. Play wave clock.

For example, when the clock reproducing unit 17 receives selection information indicating that the stream from the IP communication unit 12 is output from the stream generating unit 15, the clock reproducing unit 17 reproduces the clock of the IP broadcast wave based on the information TI2.

Broadcast wave generator 16 in broadcast retransmitting device 102B modulates the stream received from stream generator 15 to generate broadcast waves for retransmission.

More specifically, the broadcast wave generation unit 16 reads the stream from either the buffer 31 or the buffer 32 based on the selection information received from the stream generation unit 15, and according to the transmission TMCC information included in the read stream, Modulation processing of the stream is performed.

The broadcast wave generation unit 16 converts the frequency of the modulated stream to, for example, a frequency corresponding to the subscriber network 10 and generates a retransmission broadcast wave.

The broadcast wave for retransmission in the broadcast retransmission system 302 includes a clock that is reproduced from the clock included in the satellite broadcast wave received by the tuner 11 of its own or another broadcast retransmission device.

More specifically, the broadcast wave generating unit 16 in the broadcast retransmitting device 102B uses the IP broadcast wave clock reproduced by the clock reproducing unit 17 when reading the stream from the buffer 32 .

The clock of the IP broadcast wave is a clock obtained by reproducing the clock of the stream received from the tuner 11 in the broadcast retransmitting device 102A.

That is, the broadcast wave generating unit 16 in the broadcast retransmitting device 102B uses the clock of the demodulated data output from the tuner 11 in the broadcast retransmitting device 102A, that is, the reproduced clock contained in the satellite broadcast wave, to buffer 32 reads the stream.

As a result, the broadcast wave for retransmission generated by the broadcast wave generator 16 in the broadcast retransmitting device 102B includes the clock included in the satellite broadcast wave received by the tuner 11 in the broadcast retransmitting device 102A.

Then, the broadcast wave generator 16 in the broadcast retransmitting device 102B transmits the generated retransmission broadcast wave to each subscriber's home 152 via the subscriber network 10, for example.

Stream generation unit 15 in broadcast retransmitting device 102B outputs either a stream partly or wholly included in the demodulated data received from tuner 11 or a stream included in the frame received from IP communication unit 12. The configuration is not limited to the configuration in which one of the streams is selected, and a configuration in which the output of another stream can be selected is also possible.

Specifically, broadcast retransmitting apparatus 102B includes an ASI input connector for externally inputting an ASI signal, which is an ASI (Asynchronous Serial Interface) signal, for example, and stream generating section 15 receives the ASI input connector. The configuration may be such that the output of the stream included in the ASI signal received via the network can be selected.

Then, the clock recovery unit 17 in the broadcast retransmission device 102B may select the ASI signal as the clock recovery source according to the selection of the output by the stream generation unit 15 .

Further, when the output of the stream included in the ASI signal is selected by the stream generating unit 15, the broadcast wave generating unit 16 in the broadcast retransmitting device 102B uses the clock reproduced from the clock of the ASI signal by the clock reproducing unit 17. Then, a retransmission broadcast wave may be generated from the stream included in the ASI signal selected by the stream generation unit 15 and transmitted to each subscriber's home 152 via the subscriber network 10 .

FIG. 12 is a flow chart defining an operation procedure when the broadcast retransmitting apparatus according to the second embodiment of the present invention performs broadcast retransmission.

Referring to FIG. 12, first, broadcast retransmitting apparatus 102 receives and demodulates satellite broadcast waves including one or more streams forming a frame to generate demodulated data including part or all of the frame. (Step S301).

Next, broadcast retransmitting apparatus 102 generates a stream partially or wholly included in the generated demodulated data (step S302).

Next, the broadcast retransmitting device 102 accumulates the generated stream in the buffer 31 (step S303).

Next, broadcast retransmitting device 102 detects the timing of the frame included in the received satellite broadcast wave (step S304).

Further, the broadcast retransmitting device 102 receives an IP broadcast wave, which is a broadcast wave including IP packets (step S305), acquires a stream from the IP packets included in the received IP broadcast wave, and extracts frames from the acquired stream. Generate (step S306).

Next, the broadcast retransmitting device 102 accumulates the stream included in the generated frame in the buffer 32 (step S307).

Next, the broadcast retransmitting device 102 detects the timing of the generated frame (step S308).

Next, the stream generator 15 in the broadcast retransmitting device 102 selects the stream output according to the communication quality. Targets to be selected for output by the stream generation unit 15 include output of a stream generated by the stream generation unit 15 and part or all of which is included in the demodulated data received from the tuner 11, and output of a stream included in the frame received from the IP communication unit 12. There is a stream output that can be That is, the stream generation unit 15 switches between generating and outputting a stream partially or wholly included in the demodulated data and outputting the stream included in the generated frame according to the communication quality (step S309). ).

Next, the broadcast retransmitting device 102 selects a clock reproduction source according to the stream output selection. That is, the broadcast retransmitting apparatus 102 switches between reproducing the clock based on the demodulated data and reproducing the clock based on the generated frame according to the switching of the output of the stream.

If the communication quality of the satellite broadcast wave is good (YES in step S309), broadcast retransmitting apparatus 102 selects the output demodulated data as a clock reproduction source. More specifically, the broadcast retransmitting device 102 reproduces the clock included in the satellite broadcast wave based on the detected timing of the frame included in the satellite broadcast wave (step S310).

Further, the broadcast retransmitting device 102 corrects the clock frequency based on the accumulated amount of the buffer 31 (step S311).

Next, the broadcast retransmitting device 102 uses the reproduced clock to read the generated stream from the buffer 31 (step S312).

Next, the broadcast retransmission device 102 modulates the read stream to generate retransmission broadcast waves (step S313).

On the other hand, when the communication quality of the IP broadcast wave is good (NO in step S209), broadcast retransmitting apparatus 102 selects the output frame as a clock reproduction source. More specifically, the broadcast retransmitting device 102 regenerates the clock contained in the IP broadcast wave based on the timing of the generated and output frame, that is, the frame timing of the IP broadcast wave (step S314).

Further, the broadcast retransmitting device 102 corrects the clock frequency based on the accumulated amount of the buffer 32 (step S315).

Next, the broadcast retransmitting device 102 uses the reproduced clock to read the acquired stream from the buffer 32 (step S316).

Next, the broadcast retransmission device 102 modulates the read stream to generate retransmission broadcast waves (step S317).

In addition, step S303 and step S304 are not limited to the above, and the order may be changed, or they may be performed in parallel.

Further, step S305 and step S308 are not limited to the above, and the order may be changed or may be performed in parallel.

Moreover, steps S301 to S304 and steps S305 to S308 are not limited to the above, and the order may be changed or they may be performed in parallel.

Also, in the broadcast retransmitting apparatus according to the second embodiment of the present invention, the tuner 11 is configured to receive satellite broadcast waves, but the present invention is not limited to this. Tuner 11 may be configured to receive broadcast waves other than satellite broadcast waves, such as terrestrial digital broadcast waves.

Further, in the broadcast retransmission device according to the second embodiment of the present invention, the stream generation unit 15 is configured to select an output according to the communication quality of the satellite broadcast wave and the communication quality of the IP broadcast wave. However, it is not limited to this. Broadcast retransmitting device 102 may be configured, for example, to select the output of broadcast waves according to the time of day, regardless of communication quality.

As described above, in the broadcast retransmission apparatus according to the second embodiment of the present invention, the IP communication unit 12 reads out the stream generated by the stream generation unit 15 from the buffer 31, and generates IP packets containing the read stream. and transmits to the IP network 20 a retransmission broadcast wave containing the generated IP packet.

With such a configuration, it is possible to transmit the broadcast wave for retransmission via the IP network 20, so that, for example, even in areas where it is difficult to receive satellite broadcast waves, it is possible to reproduce programs included in the satellite broadcast waves. .

Further, in the broadcast retransmitting apparatus according to the second embodiment of the present invention, the IP communication unit 12 receives IP broadcast waves, which are broadcast waves including IP packets, via the IP network 20, and converts the received IP packets to Get the contained stream and generate and output frames from the retrieved stream. The stream generation unit 15 accumulates streams included in the frames received from the IP communication unit 12 in the buffer 32 . Based on the frame received from the IP communication unit 12, the detection unit 19 detects the timing of the frame.

With such a configuration, the frequency of the clock of the broadcast wave for retransmission can be matched with the frequency of the transmission clock of the IP broadcast wave by simple processing based on the frame timing of the IP broadcast wave.

Further, in the broadcast retransmitting apparatus according to the second embodiment of the present invention, the tuner 11 receives and demodulates satellite broadcast waves, which are broadcast waves including one or more streams forming a frame, and Output demodulated data including part or all. The IP communication unit 12 receives an IP broadcast wave, which is a broadcast wave including IP packets, acquires a stream included in the IP packets, generates a frame from the acquired stream, and outputs the frame. The stream generation unit 15 can select stream output. The broadcast wave generator 16 modulates the stream received from the stream generator 15 to generate broadcast waves for retransmission. The clock reproducing unit 17 reproduces the clock contained in the broadcast wave, and can select the reproduction source of the clock. Targets to be selected for output by the stream generation unit 15 include output of a stream generated by the stream generation unit 15 and part or all of which is included in the demodulated data received from the tuner 11, and output of a stream included in the frame received from the IP communication unit 12. There is a stream output that can be The clock regenerated by the clock regenerator 17 is used in the broadcast wave generator 16 . The reproduction source of the clock reproduction unit 17 includes the demodulated data received from the tuner 11 and the frame received from the IP communication unit 12 .

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave.

Therefore, with the broadcast retransmitting apparatus according to the second embodiment of the present invention, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

Further, in the broadcast retransmitting apparatus according to the second embodiment of the present invention, the stream generator 15 selects an output according to the communication quality of satellite broadcast waves and the communication quality of IP broadcast waves.

With such a configuration, it is possible to select and output broadcast waves with better communication quality, so that services such as program distribution can be provided more stably.

In the broadcast retransmitting apparatus according to the second embodiment of the present invention, tuner 11 receives and demodulates satellite broadcast waves, which are broadcast waves, and outputs demodulated data including part or all of frames. The stream generator 15 generates a stream partly or wholly included in the demodulated data received from the tuner 11 . The broadcast wave for retransmission includes a clock that is reproduced from the clock included in the satellite broadcast wave received by the tuner 11 of the own or another broadcast retransmitting device 102 .

With such a configuration, by matching the clock frequency of the retransmission broadcast wave to the clock frequency of the broadcast wave received from the other broadcast retransmission device 102 via the network, the clock frequency of the retransmission broadcast wave can be changed. , the frequency of the transmission clock of the satellite broadcast wave received by another broadcast retransmitting device 102 . That is, the frequency of the clock of the satellite broadcast wave can be transmitted via the network, and the satellite broadcast wave received by another broadcast retransmitting device 102 can be retransmitted to the subscriber's house.

Further, in the broadcast retransmission system according to the second embodiment of the present invention, broadcast retransmission device 102A receives and demodulates satellite broadcast waves, which are broadcast waves including one or more streams forming a frame. , generate a stream partly or wholly included in the demodulated data, generate IP packets containing the generated stream, and transmit IP broadcast waves, which are broadcast waves containing the generated IP packets, to the IP network 20 . Broadcast retransmitting device 102B receives and demodulates satellite broadcast waves, which are broadcast waves including frames, and generates a stream including part or all of the demodulated data. Broadcast retransmitting device 102B receives IP broadcast waves via IP network 20 and acquires a stream from the received IP broadcast waves. The broadcast retransmitting device 102B can select retransmitting broadcast waves to be transmitted to the subscriber network 10 . Retransmission broadcast waves selected by the broadcast retransmitting device 102B include retransmission broadcast waves obtained by modulating a stream generated from a satellite broadcast wave and retransmission broadcast waves obtained by modulating a stream obtained from an IP broadcast wave.

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave.

Therefore, in the broadcast retransmission system according to the second embodiment of the present invention, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

Further, in the broadcast retransmission method according to the second embodiment of the present invention, first, a satellite broadcast wave, which is a broadcast wave including one or more streams constituting a frame, is received and demodulated, and a part of the frame or Output the demodulated data containing all. Next, an IP broadcast wave, which is a broadcast wave including IP packets, is received, a stream included in the IP packets is acquired, and frames are generated from the acquired stream and output. Then select the stream output. Next, a clock reproduction source is selected, and the clock contained in the broadcast wave is reproduced. Next, the reproduced clock is used to modulate the output stream to generate a broadcast wave for retransmission. When selecting the output of the stream, there are the output of the generated stream partly or wholly included in the output demodulated data and the output of the stream included in the output frame. The sources of clock reproduction include output demodulated data and output frames.

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave.

Therefore, with the broadcast retransmission method according to the second embodiment of the present invention, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

Further, in the broadcast retransmission method according to the second embodiment of the present invention, first, the broadcast retransmission device 102A receives a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame. It demodulates, generates a stream contained in the demodulated data, generates IP packets containing the generated stream, and transmits IP broadcast waves, which are broadcast waves containing the generated IP packets, to the IP network. Next, the broadcast retransmitting device 102B receives and demodulates satellite broadcast waves, which are broadcast waves including frames, and generates a stream partly or wholly included in the demodulated data. Next, the broadcast retransmitting device 102B receives IP broadcast waves via the IP network 20 and acquires a stream from the received IP broadcast waves. Next, the broadcast retransmitting device 102B selects a retransmitting broadcast wave to be transmitted to the subscriber network 10. FIG. Retransmission broadcast waves selected by the broadcast retransmitting device 102B include retransmission broadcast waves obtained by modulating a stream generated from a satellite broadcast wave and retransmission broadcast waves obtained by modulating a stream obtained from an IP broadcast wave.

In this manner, by selecting and retransmitting satellite broadcast waves or IP broadcast waves, services such as program distribution can be more stably provided to subscribers. In addition, with the configuration for selecting the target of clock reproduction, it is possible to reproduce the clock corresponding to the selected broadcast wave.

Therefore, with the broadcast retransmission method according to the second embodiment of the present invention, it is possible to construct an excellent system for retransmitting broadcast waves to subscribers' homes via a network.

Since other configurations and operations are similar to those of the broadcast retransmission system according to the first embodiment, detailed description will not be repeated here.

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

The above description includes the features appended below.
[Appendix 1]
A broadcast retransmission device that receives a broadcast wave containing one or more streams that form a frame,
a stream generator that generates the stream included in the received broadcast wave and stores it in a buffer;
a broadcast wave generation unit that reads the stream generated by the stream generation unit from the buffer and modulates the read stream to generate a retransmission broadcast wave;
a detection unit that detects the timing of the frame included in the received broadcast wave;
a clock reproduction unit that reproduces the clock contained in the broadcast wave based on the timing detected by the detection unit and corrects the frequency of the clock based on the accumulated amount of the buffer;
The clock reproduced by the clock reproduction unit is used for processing of the broadcast wave generation unit including reading of the stream,
The stream generation unit writes the stream to the buffer using a clock included in the broadcast wave;
A broadcast retransmission device, wherein the buffer is a FIFO.

[Appendix 2]
a tuner that receives and demodulates satellite broadcast waves, which are broadcast waves containing one or more streams that form a frame, and outputs demodulated data containing part or all of the frame;
an IP communication unit that receives an IP broadcast wave that is a broadcast wave including IP packets, acquires a stream included in the IP packets, generates and outputs a frame from the acquired stream;
a stream generator capable of selecting the output of the stream;
a broadcast wave generation unit that modulates the stream received from the stream generation unit to generate a retransmission broadcast wave;
a clock reproducing unit that reproduces the clock contained in the broadcast wave and can select a reproduction source,
The selection target of the output by the stream generation unit includes the output of the stream generated by the stream generation unit, part or all of which is included in the demodulated data received from the tuner, and the output of the stream received from the IP communication unit. an output of said stream contained in said frame;
The clock reproduced by the clock reproduction unit is used in the broadcast wave generation unit,
the reproduction source of the clock reproduction unit includes the demodulated data received from the tuner and the frame received from the IP communication unit;
The broadcast retransmission device further comprises a buffer for accumulating the stream,
The stream generation unit writes the stream to the buffer using a clock included in the broadcast wave;
A broadcast retransmission device, wherein the buffer is a FIFO.

[Appendix 3]
a first broadcast retransmission device;
a second broadcast retransmission device;
The first broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, and generates the stream partly or wholly included in the demodulated data. generating IP packets containing the generated stream, transmitting IP broadcast waves, which are broadcast waves containing the generated IP packets, to an IP network;
The second broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including frames, and generates a stream including part or all of the demodulated data,
The second broadcast retransmission device receives the IP broadcast wave via the IP network, acquires the stream from the received IP broadcast wave,
The second broadcast retransmission device is capable of selecting a retransmission broadcast wave to be transmitted to a subscriber network,
The retransmission broadcast waves selected by the second broadcast retransmission device include retransmission broadcast waves obtained by modulating the stream generated from the satellite broadcast waves, and modulated streams obtained from the IP broadcast waves. There is a broadcast wave for retransmission,
The first broadcast retransmission device and the second broadcast retransmission device each include a buffer for accumulating the stream,
The first broadcast retransmission device and the second broadcast retransmission device write the stream to the buffer using a clock included in the broadcast wave,
A broadcast retransmission system, wherein said buffer is a FIFO.

10 subscriber network 11 tuner 12 IP communication unit 15 stream generation unit 16 broadcast wave generation unit 17 clock reproduction unit 18 VCO
19 detection unit 20 IP network 21 storage unit 31, 32 buffer 81 external antenna 101 broadcast retransmission device 151 station building 152 subscriber's home 131 STB
133 TV monitor

Claims (7)

a tuner that receives and demodulates satellite broadcast waves, which are broadcast waves containing one or more streams that form a frame, and outputs demodulated data containing part or all of the frame;
an IP communication unit that receives an IP broadcast wave that is a broadcast wave including IP packets, acquires a stream included in the IP packets, generates and outputs a frame from the acquired stream;
a stream generator capable of selecting the output of the stream;
a broadcast wave generation unit that modulates the stream received from the stream generation unit to generate a retransmission broadcast wave;
a clock reproducing unit that reproduces the clock contained in the broadcast wave and can select a reproduction source,
The selection target of the output by the stream generation unit includes the output of the stream generated by the stream generation unit, part or all of which is included in the demodulated data received from the tuner, and the output of the stream received from the IP communication unit. an output of said stream contained in said frame;
The clock reproduced by the clock reproduction unit is used in the broadcast wave generation unit,
The broadcast retransmission device, wherein the reproduction source of the clock reproduction unit includes the demodulated data received from the tuner and the frame received from the IP communication unit. 2. The broadcast retransmitting device according to claim 1 , wherein said stream generator selects said output according to communication quality of said satellite broadcast wave and communication quality of said IP broadcast wave. The broadcast retransmission device further
a tuner that receives and demodulates the satellite broadcast wave, which is the broadcast wave, and outputs demodulated data including part or all of the frame;
The stream generation unit generates the stream partly or wholly included in the demodulated data received from the tuner,
3. The broadcast retransmission according to claim 1, wherein said broadcast wave for retransmission includes a clock obtained by reproducing a clock included in said satellite broadcast wave received by said tuner in said broadcast retransmitting apparatus or said other broadcast retransmitting device. Device. 4. The broadcast retransmitting apparatus according to any one of claims 1 to 3, wherein said broadcast wave is a broadcast wave of advanced wideband satellite digital broadcasting. a first broadcast retransmission device;
a second broadcast retransmission device;
The first broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, and generates the stream partly or wholly included in the demodulated data. generating IP packets containing the generated stream, transmitting IP broadcast waves, which are broadcast waves containing the generated IP packets, to an IP network;
The second broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including frames, and generates a stream including part or all of the demodulated data,
The second broadcast retransmission device receives the IP broadcast wave via the IP network, acquires the stream from the received IP broadcast wave,
The second broadcast retransmission device is capable of selecting a retransmission broadcast wave to be transmitted to a subscriber network,
The retransmission broadcast waves selected by the second broadcast retransmission device include retransmission broadcast waves obtained by modulating the stream generated from the satellite broadcast waves, and modulated streams obtained from the IP broadcast waves. A broadcast retransmission system comprising a retransmission broadcast wave. A broadcast retransmission method in a broadcast retransmission device,
a step of receiving and demodulating a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, and outputting demodulated data including part or all of the frame;
a step of receiving an IP broadcast wave, which is a broadcast wave including IP packets, obtaining a stream included in the IP packets, generating and outputting frames from the obtained stream;
selecting an output of said stream;
selecting a reproduction source and reproducing a clock included in the broadcast wave;
using the reproduced clock to modulate the output stream to generate a retransmission broadcast wave;
The selection targets in the step of selecting the output include the output of the generated stream that is partly or wholly included in the output demodulated data, and the output of the stream that is included in the output frame. there is
The broadcast retransmission method, wherein the reproduction source includes the output demodulated data and the output frame. A broadcast retransmission method in a broadcast retransmission system comprising a first broadcast retransmission device and a second broadcast retransmission device,
The first broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including one or more streams forming a frame, generates the stream included in the demodulated data, and generates the stream. a step of generating an IP packet containing and transmitting an IP broadcast wave, which is a broadcast wave containing the generated IP packet, to an IP network;
a step in which the second broadcast retransmission device receives and demodulates a satellite broadcast wave, which is a broadcast wave including frames, to generate a stream partly or wholly included in the demodulated data;
a step in which the second broadcast retransmission device receives the IP broadcast wave via the IP network and obtains a stream from the received IP broadcast wave;
selecting a retransmission broadcast wave to be transmitted to a subscriber network by the second broadcast retransmission device;
The retransmission broadcast waves selected by the second broadcast retransmission device include retransmission broadcast waves obtained by modulating the stream generated from the satellite broadcast waves, and modulated streams obtained from the IP broadcast waves. A broadcast retransmission method comprising a retransmission broadcast wave.

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