Transmitting device and receiving device

Abstract

To provide a transmitter and a receiver for performing bulk transmission by dividing data considering reordering in TLV packet form using a plurality of broadcasting transmission channels including two kinds of frequency bandwidth, providing high compatibility with an IP-based transmission channel.SOLUTION: A transmitter 11 of the present invention: converts bulk data inputted from a signal source device 10 into a format for TLV packet form signal; configures a division frame by adding a basic division slot for routing through an IP network 19 as required to a basic division slot using common error correction codes for two kinds of frequency bandwidth of a broadcasting transmission channel; adds identification information for uniquely indicating order of signals at the beginning of the basic division frame for each transmission channel; and transmits the data to a receiver 17 in a division manner. The receiver 17 of the present invention reconfigures the division frame based on the identification information when receiving the data in bulk transmission by the transmitter 11, reconstructs data by concatenating valid data from the reconfigured frame, and outputs the reconstructed data to external.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the technical fields of satellite broadcasting, terrestrial broadcasting, fixed communication, and mobile communication, and in particular to a transmitting device and a receiving device for time division multiplexing transmission of digital data. [Background technology]

[0002] In digital transmission systems, multi-level modulation methods are often used so that more information can be transmitted within the frequency bandwidth available for each service. Increasing the number of bits allocated per symbol of the modulated signal (modulation order) is an effective way to increase frequency utilization efficiency, but the relationship between the upper limit of the information speed that can be transmitted per 1 Hz frequency and the signal-to-noise ratio is restricted by the Shannon limit. One example of information transmission using a satellite transmission path is satellite digital broadcasting.

[0003] In currently used digital satellite broadcasting, information correction is performed in the receiving device using error correction codes. By adding a redundant signal called a parity bit to the information to be transmitted, it is possible to control the signal redundancy (coding rate) and increase resistance to noise. Error correction codes and modulation methods are closely related, and the theoretical upper limit of frequency utilization efficiency relative to the signal-to-noise ratio is called the Shannon limit. In 1962, Gallagher proposed the LDPC (Low Density Parity Check) code as one of the powerful error correction codes with performance approaching the Shannon limit (see, for example, Non-Patent Document 1).

[0004] The LDPC code is a linear code defined by a very sparse check matrix H (the elements of the check matrix are made up of 0 and 1, and the number of 1s is very small).

[0005] LDPC codes are powerful error correcting codes that can achieve transmission characteristics approaching the Shannon limit by increasing the code length and using an appropriate check matrix, and LDPC codes are also adopted in ARIB STD-B44 (hereinafter referred to as the Advanced Satellite Broadcasting System (ISDB-S3) (see Non-Patent Document 2 for example), which specifies the transmission system for 4K / 8K Super Hi-Vision satellite broadcasting, which is the current and next-generation broadcasting service.) By combining multi-level modulation with powerful error correcting codes such as LDPC codes, it has become possible to achieve transmission with higher frequency utilization efficiency.

[0006] Taking the advanced satellite broadcasting system (ISDB-S3) as an example, the code length of the LDPC code in this system is 44,880 bits, configured with a forward error correction (FEC) frame, and has been shown to have a performance within approximately 1 dB from the BPSK limit (theoretical upper limit of frequency utilization efficiency for signal-to-noise ratio when the signal point arrangement is BPSK) (see, for example, Non-Patent Document 3).

[0007] In addition, in the advanced satellite broadcasting system (ISDB-S3), 11 types of LDPC coding rates are defined: 41 / 120 (≒1 / 3), 49 / 120 (≒2 / 5), 61 / 120 (≒1 / 2), 73 / 120 (≒3 / 5), 81 / 120 (≒2 / 3), 89 / 120 (≒3 / 4), 93 / 120 (≒7 / 9), 97 / 120 (≒4 / 5), 101 / 120 (≒5 / 6), 105 / 120 (≒7 / 8), and 109 / 120 (≒9 / 10).

[0008] In addition to the current 2K services provided by satellite and terrestrial broadcasting, and 4K and 8K Super Hi-Vision services provided by satellite broadcasting, there are high expectations for the provision of 4K and 8K Super Hi-Vision services by terrestrial broadcasting. However, when we look at the 12 GHz band used for satellite broadcasting, available frequencies are tight, and it is difficult to secure sufficient frequency bandwidth for the transmission of next-generation content beyond 4K and 8K services.

[0009] In addition, while the 12 GHz band is allocated to ISDB-S3, another band that can be used for satellite broadcasting is the 21 GHz band, which has been allocated a bandwidth of 600 MHz for satellite broadcasting, making it a promising transmission band for realizing large-capacity transmission.

[0010] However, since the 21 GHz band is more affected by rain attenuation than the 12 GHz band, in order to ensure a sufficient C / N margin, technical solutions are required for the transmission method, such as the application of powerful error correction codes, such as the above-mentioned LDPC code, and reducing the number of modulation levels. In addition, the 21 GHz band wideband transmission method is one transmission method that has a track record of transmission using a 21 GHz band broadcasting satellite and uses the same error correction code as ISDB-S3 (see, for example, Non-Patent Documents 4 and 5).

[0011] In the situation where sufficient bandwidth cannot be secured, there is a technique called bulk transmission, which divides large-capacity transmission into bands and transmits them (see, for example, Patent Document 1). In the field of communications, a technique for dividing and transmitting data is also known, and is realized as carrier agreement (see, for example, Non-Patent Document 6). [Prior art documents] [Patent documents]

[0012] [Patent Document 1] JP 2009-260408 A [Non-patent literature]

[0013] [Non-Patent Document 1] R. G Gallager, “Low Density Parity Check Codes,” in Research Monograph series Cambridge, MIT Press, 1963 [Non-Patent Document 2] “Advanced Wideband Digital Satellite Broadcasting Transmission Method (ISDB-S3) Standard ARIB STD-B44 Version 2.1”, [online], revised March 25, 2016, ARIB, [Retrieved December 5, 2020], Internet〈URL:https: / / www.arib.or.jp / kikaku / kikaku_hoso / std-b44.html〉 [Non-Patent Document 3] Suzuki et al., "Design of LDPC Codes for Advanced BS Digital Broadcasting", Journal of the Institute of Image Information and Television Engineers, Institute of Image Information and Television Engineers, vol.62, No.12, December 1, 2008, pp.1997-2004 [Non-Patent Document 4] Y.Suzuki et al., BCH and LDPC Coded Wide-band Modem for 21-GHz Band Satellite Broadcasting System, IEEE Radio & Wireless Week 2015(IEEE RWW 2015), MO1D-2, pp.4-6 [Non-Patent Document 5] Suzuki et al., “21 GHz Band Broadband Satellite Transmission Experiment Using B-SAT4a Satellite”, Technical Report of the Institute of Electronics, Information and Communication Engineers, The Institute of Electronics, Information and Communication Engineers, IEICE Technical Report SAT2018-76 (February 2019), pp.109-114 [Non-Patent Document 6] “No. 659: What is Carrier Aggregation?”, [online], [Retrieved December 5, 2020], Internet〈URL:https: / / k-tai.watch.impress.co.jp / docs / column / keyword / 645492.html〉 Summary of the Invention [Problem to be solved by the invention]

[0014] As described above, in a situation where a sufficient bandwidth cannot be secured, a technique called bulk transmission is known in which a large-capacity transmission is divided into bands and transmitted.

[0015] In addition, with the recent convergence of broadcasting and communications, the diversification of transmission formats beyond the boundaries of radio waves is progressing, and in particular, the construction of transmission systems that transmit data using communication transmission paths and broadcast transmission paths in communication transmission methods based on IP (Internet Protocol) is progressing. The fusion with broadcast transmission paths (especially satellite transmission paths) is also effective for next-generation communication networks such as the 5th generation mobile communication system (5G), and it is expected that in the future, the demand for standardization of broadcast transmission methods with IP-based communication transmission methods will further accelerate.

[0016] For example, in a situation where satellite broadcasting frequencies in the 12 GHz band are tight, the bulk transmission broadcasting technology that enables large-capacity transmission can expand the transmission capacity by using both the 12 GHz and 21 GHz bands, but to achieve this, a more efficient transmission system is required. Also, a system with high compatibility with IP-based communication transmission methods is required. That is, in the future, in a situation where sufficient bandwidth cannot be secured for data transmission, a technique is desired that can divide large-capacity data by band (frequency allocation) using multiple broadcast transmission paths and transmit it in bulk, and that can be integrated into the communication transmission path of the IP-based communication transmission method and easily convert or combine the transmitted data. Therefore, at least in the advanced satellite broadcasting system (ISDB-S3) used for 4K / 8K satellite broadcasting, a transmitter and a receiver are required that can be simultaneously used with the 21 GHz band, which can further expand the transmission capacity, and that have high compatibility with IP-based communication transmission paths, and that can control the bulk transmission of large-capacity data by dividing it by band (frequency allocation) using multiple broadcast transmission paths.

[0017] Another technical issue with control in implementing bulk transmission is that when transmitting various divided signals, reordering occurs, in which signals are swapped back and forth during the signal transmission process. In particular, reordering occurs frequently in IP networks, because the order of signal transmission is not guaranteed.

[0018] Therefore, in consideration of the above-mentioned problems, the object of the present invention is to provide a transmitting device and a receiving device which enable an expansion of transmission capacity by utilizing both bands of multiple broadcast transmission paths including two types of frequency bands (in the embodiment example, satellite broadcast transmission paths of 12 GHz band and 21 GHz band), while having high affinity with IP-based communication transmission paths, and which divides and bulk transmits predetermined data in TLV (Type Length Value) packet format using multiple broadcast transmission paths, thereby enabling the receiving side to appropriately restore the signal order to the original order even when a change in the signal order occurs due to reordering, etc. [Means for solving the problem]

[0019] The transmitting device of the present invention is a transmitting device which transmits predetermined data in bulk in a TLV (Type Length Value) packet format by using a plurality of broadcast transmission paths, and includes: a TLV signal generating means which inputs predetermined data to be the subject of bulk transmission from a signal source device and converts the data into a signal in a TLV packet format; a TLV signal generating means which determines divided frames of a frame length conforming to an independent transmission method which applies a common error correction code to a plurality of broadcast transmission paths including two types of frequency bands used for the bulk transmission; and configures the divided frames with a basic divided slot based on a maximum transmission rate of a broadcast transmission path of a first frequency band among information bit rates required for transmitting the predetermined data; when the information bit rate required for transmitting the predetermined data exceeds a maximum transmission rate transmittable on the broadcast transmission path of the first frequency band among the plurality of broadcast transmission paths, the divided frames are further configured with a basic divided slot based on a ratio between a maximum transmission rate of a broadcast transmission path of a second frequency band among the plurality of broadcast transmission paths and a maximum transmission rate of the broadcast transmission path of the first frequency band; and when the information bit rate exceeds the maximum transmission rate transmittable on the broadcast transmission paths of the first frequency band and the second frequency band, the divided frames are further configured with a basic divided slot based on an IP (Internet and a segmented frame generating means for controlling each transmitter in the plurality of broadcast transmission paths and a connection to the communication transmission paths so as to configure the segmented frame by adding a predetermined number of basic segmented slots for transmission via a communication transmission path of a Broadcast Protocol (Broadcasting Protocol) network, and to divide and transmit predetermined data converted into the TLV packet format signal based on the segmented frame, wherein the segmented frame generating means comprises: a means for adding identification information for uniquely indicating a signal order of the segmented frame to the beginning of a basic segmented slot for each transmission path that configures the segmented frame to be assigned to the broadcast transmission path of the first frequency band, the broadcast transmission path of the second frequency band, and the communication transmission path; and a means for using an LDPC code as a common error correcting code and adjusting the number of TLV packets that can be accommodated in each basic segmented slot, the number of segments of the basic segmented slot, and a NULL length according to a coding rate of the LDPC code in order to input the TLV packet format signal to both the broadcast transmission path of the first frequency band and the broadcast transmission path of the second frequency band without excess or deficiency.

[0020] In addition, in the transmitting device of the present invention, the divided frame generating means determines in a TLV header a setting for distinguishing a first TLV packet indicating a first TLV packet from other TLV packets in each basic divided slot for each basic divided slot that constitutes the divided frame and that is assigned to each transmission path of the broadcast transmission path of the first frequency band, the broadcast transmission path of the second frequency band, and the communication transmission path, and configures the divided frame so that the receiving side can identify which TLV packet indicates the head of which basic divided slot in which divided frame and via which transmission path it is.

[0021] In addition, in the transmitting device of the present invention, the divided frame generating means is characterized in having a means for incrementing the numerical value of the packet type field in the first TLV packet indicating the first TLV packet of each basic divided slot from a predetermined initial value, repeating the increment within a predetermined range to form the identification information, and assigning it to each basic divided slot.

[0022] In addition, in the transmitting device of the present invention, the broadcast transmission path of the first frequency band is a 12 GHz band satellite transmission path, and the broadcast transmission path of the second frequency band is a 21 GHz band satellite transmission path, and the divided frame generating means, when constructing the divided frame, calculates the corresponding information bit rate based on the coding and modulation method of each of the multiple broadcast transmission paths, inserts nulls after the data assigned according to each information bit rate so that the frame length of the divided frame constituting each basic divided slot is a constant value, forms basic divided slots for the multiple broadcast transmission paths, assigns data for the broadcast transmission path of the first frequency band to the first basic divided slot in the divided frame, assigns data for the broadcast transmission path of the second frequency band from the second basic divided slot onwards, and assigns the remaining data that exceeds the maximum rate that can be transmitted on the broadcast transmission paths of the first frequency band and the second frequency band to a predetermined number of basic divided slots for transmission via the communication transmission path of the IP network.

[0023] In addition, in the transmitting device of the present invention, the divided frame generating means is characterized in that, when dividing the specified data in TLV packet format and transmitting it in bulk, it is possible to change the number of slot divisions of the basic divided slots that constitute the divided frame, and it has a means for notifying the receiving side of information on the number of slot divisions of the basic divided slots that constitute the divided frame and the unique number of each basic divided slot.

[0024] In addition, the transmitting device of the present invention is characterized in that, when the divided frame constructed by the divided frame generating means includes a predetermined number of basic divided slots for transmission via a communication transmission path of an IP network, the transmitting device further comprises IP encapsulation means for dividing the predetermined number of basic divided slots into IP-based packets that are consistent with the IP network, and for assigning an IP sequence number to each divided IP-based packet to uniquely indicate the signal order of the packets, and transmitting the divided IP-based packets to a receiving device.

[0025] Furthermore, the receiving device of the present invention is a receiving device that receives the predetermined data bulk-transmitted by the transmitting device of the present invention, and includes a divided frame reconstructing means for receiving signals in TLV packet format bulk-transmitted via the plurality of broadcast transmission paths and the communication transmission path and reconstructing corresponding basic divided slots, and for IP-based packets transmitted via the communication transmission path of an IP network, performing IP decapsulation, arranging the signal order based on an IP sequence number for uniquely indicating the signal order given in the packet, extracting TLV signals and reconstructing the predetermined number of basic divided slots, and rearranging the divided frames generated by the transmitting device based on the identification information, and a divided frame reconstructing means for reconstructing each basic divided slot based on the reconstructed divided frames. and an output signal generating means for concatenating valid data of the divided slots, restoring predetermined data of the same signal format as that sent from the signal source device, and outputting the restored data externally. The divided frame reconstructing means, when receiving the signal in the TLV packet format via both the broadcast transmission path of the first frequency band and the broadcast transmission path of the second frequency band, reconstructs a divided frame consisting of the predetermined number of basic divided slots by adjusting the number of TLV packets that can be accommodated in each basic divided slot, the number of divisions of the basic divided slots, and the NULL length in accordance with the coding rate of the LDPC code, based on the number of basic divided slots calculated by the ratio of the information bit rate that can be transmitted through the broadcast transmission path of the second frequency band to the maximum bit rate of the broadcast transmission path of the first frequency band.

[0026] In addition, in the receiving device of the present invention, the divided frame reconstruction means determines the first TLV packet based on the setting information in the TLV header of the TLV packet format signals received via the multiple broadcast transmission paths and the communication transmission path, identifies which TLV packet indicates the beginning of which basic divided slot in which divided frame, determines the TLV header between the basic divided frames, and rearranges the divided frames to reconstruct the divided frames generated by the transmitting device.

[0027] In addition, in the receiving device of the present invention, the identification information is formed by incrementing the value of the packet type field in the head TLV packet indicating the head TLV packet of each basic division slot from a predetermined initial value and repeating the increment within a predetermined range, and is added to each basic division slot, and the divided frame reconstruction means is characterized in that it rearranges the divided frames to reconstruct them based on the value of the packet type field in the head TLV packet added as the identification information among the signals in TLV packet format received via the multiple broadcast transmission paths and the communication transmission path.

[0028] In addition, in the receiving device of the present invention, the divided frame reconstructing means, when reconstructing the divided frames, calculates the corresponding information bit rates based on the coding and modulation method of each of the multiple broadcast transmission paths, and inserts nulls after the data assigned according to each information bit rate so that the frame length of the divided frames constituting each basic divided slot becomes a constant value, thereby forming basic divided slots for the multiple broadcast transmission paths, and basic divided slots for the communication transmission path in accordance with the multiple broadcast transmission paths.

[0029] In addition, in the receiving device of the present invention, the divided frame reconstruction means is characterized by having a means for identifying the structure of the divided frame to be reconstructed based on information on the number of slot divisions of the basic divided slots that constitute the divided frame and the unique number of each basic divided slot, which information is notified in advance by the transmitting device. Effect of the Invention

[0030] According to the present invention, even in an environment where the frequency of the broadcast transmission path is constrained, by using multiple broadcast transmission paths including two types of frequency bands (satellite broadcast transmission paths of 12 GHz band and 21 GHz band in the embodiment example), it is possible to increase the overall transmission capacity related to data transmission and realize a transmission system with high affinity with IP. In particular, it is possible to easily and stabilize the data transmission synchronization between the transmitting device and the receiving device, improve the ease of connection (ease of synchronization of connection timing) to the broadcast transmission path and the communication transmission path to be used, and even when the signal order is changed due to reordering or the like, the receiving device can appropriately return the signal order to the original order. [Brief description of the drawings]

[0031] [Figure 1] 1 is a block diagram showing a schematic configuration of a transmission system including a transmitting device and a receiving device according to an embodiment of the present invention; [Diagram 2] 1 is a block diagram showing a schematic configuration of a transmitting device according to an embodiment of the present invention; [Diagram 3] 1 is a diagram showing the structure of a TLV packet used in a transmitting device according to an embodiment of the present invention. [Figure 4] 2 is a diagram showing the configuration of a divided frame used in a transmitting device according to an embodiment of the present invention. FIG. [Diagram 5] 1 is a diagram showing the configuration of a first TLV packet relating to a divided frame used in a transmitting device according to an embodiment of the present invention. [Figure 6] This figure shows an example in which the numerical value of the packet type field in the first TLV packet is incremented within a predetermined range as identification information for uniquely indicating the signal order of the divided frame in each basic divided slot that constitutes the divided frame in a transmitting device according to one embodiment of the present invention. [Figure 7] 1 is a diagram illustrating the relationship between the ISDB-S3 modulation scheme, LDPC coding rate, payload size of a basic division slot, and the length of a null (NULL (ISDB-S3)) to be inserted in one embodiment of the present invention. FIG. [Figure 8]1 is a diagram showing an example of a transmission symbol frame configuration in a 21 GHz band wideband transmitter according to the present invention. [Figure 9] 1 is a diagram illustrating an example of an error correction code for a 21 GHz wideband transmitter according to the present invention. [Figure 10] FIG. 1 is a diagram illustrating a relationship between an LDPC coding rate and a TLV packet payload length (k) according to the present invention. [Figure 11] FIG. 11 illustrates an example of the relationship between the information bit rate (I21GHz) for each coding rate when the modulation method is QPSK, the symbol rate is 250Mbaud, and the phase reference burst signal length is 4, the number of slots (n-2) of the basic division slots, and the number of error correction code packets (number of LDPC packets P21GHz) in the 21GHz wideband transmitter according to the present invention. [Figure 12] FIG. 2 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 1 / 2, which are input to a 21 GHz wideband transmitter according to the present invention. [Figure 13] FIG. 11 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 3 / 5, which are input to a 21 GHz wideband transmitter according to the present invention. [Figure 14] FIG. 11 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 2 / 3, which are input to a 21 GHz band wideband transmitter according to the present invention. [Figure 15] FIG. 11 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 3 / 4, which are input to a 21 GHz band wideband transmitter according to the present invention. [Figure 16] 1 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 4 / 5 input to a 21 GHz band wideband transmitter according to the present invention. FIG. [Figure 17] FIG. 11 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 5 / 6, which are input to a 21 GHz band wideband transmitter according to the present invention. [Figure 18] FIG. 1 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 7 / 8, which are input to a 21 GHz wideband transmitter according to the present invention. [Figure 19] FIG. 11 is a diagram showing an example of a packet allocation configuration of basic divided slots with an LDPC coding rate of 9 / 10, which are input to a 21 GHz wideband transmitter according to the present invention. [Figure 20] FIG. 11 is a diagram showing an example of the configuration of basic division slots when the coding and modulation scheme supported by the ISDB-S3 transmitter of the present invention is set to 16APSK (LDPC coding rate: 7 / 9) and the coding and modulation scheme supported by the 21 GHz wideband transmitter 12-2 is QPSK (LDPC coding rate: 2 / 3). [Figure 21] A diagram showing a packet structure including an IP sequence number that is assigned for split transmission of an IP-based packet when a split frame includes a basic split slot that utilizes transmission via an IP network in a transmitting device of one embodiment of the present invention. [Figure 22] 1 is a block diagram showing a schematic configuration of a receiving device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, a transmission system 1 including a transmitting device 11 and a receiving device 17 according to an embodiment of the present invention will be described in detail with reference to the drawings.

[0033] (Transmission System) Fig. 1 is a block diagram showing a schematic configuration of a transmission system 1 including a transmitter 11 and a receiver 17 according to an embodiment of the present invention. In the example of the transmission system 1 shown in Fig. 1, a signal source device 10, a transmitter 11, an ISDB-S3 transmitter 12-1 for signal transmission via a 12 GHz band broadcast satellite 14-1, a wideband transmission transmitter 12-2 for signal transmission via a 21 GHz band broadcast satellite 14-2, an ISDB-S3 transmitting antenna 13-1, a 21 GHz band wideband transmission transmitting antenna 13-2, a 12 GHz band broadcast satellite 14-1, a 21 GHz band broadcast satellite 14-2, a 12 GHz band receiving antenna 15-1, a 21 GHz band receiving antenna 15-2, an ISDB-S3 receiver 16-1, a 21 GHz band wideband transmission receiver 16-2, a receiver 17, a display device 18, and an IP network 19.

[0034] The ISDB-S3 transmitter 12-1 and the corresponding ISDB-S3 receiver 16-1 in the transmission system 1 according to the present embodiment are devices conforming to the advanced satellite broadcasting system (ISDB-S3), and are capable of transmitting data using the coding and modulation system (LDPC code and the maximum multi-level modulation 32APSK under the current standard) supported by ISDB-S3. The ISDB-S3 transmitting antenna 13-1, the 12 GHz band broadcasting satellite 14-1, and the 12 GHz band receiving antenna 15-1 used in the ISDB-S3 transmission system are all configured as transmitting and receiving systems assuming the use of the 12 GHz band. In other words, the ISDB-S3 transmitter 12-1 performs LDPC coding processing according to a predetermined LDPC coding rate on the data to be transmitted based on the ISDB-S3 system under the use of the 12 GHz band (BCH code may be added), generates a modulated signal that has been subjected to mapping according to a predetermined modulation system, and uplinks it to the 12 GHz band broadcasting satellite 14-1. The 12 GHz band broadcasting satellite 14-1 downlinks the modulated signal to the 12 GHz band receiving antenna 15-1. The ISDB-S3 receiver 16-1 receives the modulated signal via the 12 GHz band receiving antenna 15-1 and performs demodulation and decoding processing corresponding to the coding and modulation method of the ISDB-S3 transmitter 12-1 to restore the data transmitted from the ISDB-S3 transmitter 12-1. Note that a single receiver may be configured to have the functions of multiple ISDB-S3 receivers 16-1.

[0035] Similarly, the 21 GHz wideband transmitter 12-2 and the corresponding 21 GHz wideband receiver 16-2 in the transmission system 1 according to the present embodiment are devices conforming to a wideband transmission method different from ISDB-S3 (for example, see Non-Patent Documents 4 and 5). In this wideband transmission method, a 600 MHz band in the 21 GHz band is assumed to be allocated, and, as an example, the band is divided into two channels with a symbol rate of 250 Mbaud per channel, so that a signal is transmitted with a simple transmission symbol frame configuration, while the LDPC code and BCH code, which are error correction codes, are common to ISDB-S3, in order to operate at a higher symbol rate (see FIG. 8 described later). In the example shown in FIG. 8, the maximum selectable multi-level modulation is 8PSK as a countermeasure against rain attenuation in the 21 GHz band, and further, as a countermeasure against synchronization reinforcement, the length of the phase reference burst signal can be set to a maximum of 16 symbols per 187 symbols of the main signal. In addition, the 21 GHz band transmitting antenna 13-2, the 21 GHz band broadcasting satellite 14-2, and the 21 GHz band receiving antenna 15-2 used in the transmission system of the 21 GHz band wideband transmission are all configured as transmitting and receiving systems assuming the use of the 21 GHz band. In other words, the 21 GHz band wideband transmitter 12-2 performs LDPC coding processing according to a predetermined LDPC coding rate on the data to be transmitted based on the 21 GHz band wideband transmission method under the use of the 21 GHz band (BCH code may be added), generates a modulated signal that has been subjected to mapping according to a predetermined modulation method, and uplinks it to the 21 GHz band broadcasting satellite 14-2. The 21 GHz band broadcasting satellite 14-2 downlinks the modulated signal to the 21 GHz band receiving antenna 15-2. The 21 GHz band wideband receiver 16-2 receives the modulated signal via the 21 GHz band receiving antenna 15-2, performs demodulation and decoding processing corresponding to the coding and modulation method of the 21 GHz band wideband transmitter 12-2, and restores the data transmitted from the 21 GHz band wideband transmitter 12-2. Note that a single receiver may be configured to have the functions of multiple 21 GHz band wideband receivers 16-2.

[0036] That is, for example, M (M is an integer of 1 or more) ISDB-S3 transmitters 12-1, M ISDB-S3 transmitting antennas 13-1, 12 GHz broadcasting satellite 14-1, M 12 GHz receiving antennas 15-1, M ISDB-S3 receivers 16-1, N (N is an integer of 1 or more) 21 GHz wideband transmitters 12-2, N 21 GHz transmitting antennas 13-2, 21 GHz broadcasting satellite 14-2, N 21 GHz receiving antennas 15-2, and N 21 GHz wideband receivers 16-2 constitute a plurality (M+N) of broadcast transmission paths, similar to a so-called Multi-Input Multi-Output (MIMO) or Multi-Input Single-Output (MISO) broadcast transmission system. The IP network 19 constitutes a communication transmission path in an IP-based communication transmission method. For example, the IP network 19 can be a general communication transmission path constituted by an Internet protocol such as IPv4 or IPv6. In this embodiment, a plurality of satellite transmission paths are used as the broadcast transmission paths, but the present invention is not limited to this, and a plurality of next-generation terrestrial transmission paths may be used.

[0037] The transmitting device 11 then controls M ISDB-S3 transmitters 12-1 and N 21 GHz band transmitting devices 12-2 to bulk transmit large amounts of data obtained from the signal source device 10 to the receiving device 17 using multiple broadcast transmission paths (in this example, 12 GHz band and 21 GHz band satellite transmission paths) and, if necessary, a communication transmission path via an IP network 19.

[0038] 1 is a device that transmits data to be transmitted in this transmission system 1 to a transmitter 11, and the transmitter 11 can also use a communication transmission path by an IP network 19. That is, the signal source device 10 is capable of transmitting data to the transmitter 11 at a transmission rate higher than the maximum transmission rate (information bit rate of 146.6735 Mbps in 32APSK (9 / 10)) that can be transmitted by an ISDB-S3 transmitter 12-1 defined by ISDB-S3, and even at a transmission rate higher than the maximum transmission rate (symbol rate 250 Mbaud, information bit rate of 633.2 bps in 8PSK (9 / 10)) that can be transmitted by a 21 GHz wideband transmitter 12-2 in a 21 GHz wideband transmission method. In this specification, the term "modulation method (LDPC coding rate)" may be used for explanation. For example, 32APSK(9 / 10) means that the modulation method is 32APSK and the LDPC coding rate is 9 / 10. In addition, in this specification, when the term "coding rate" is used simply, it means the "LDPC coding rate."

[0039] Hereinafter, a representative description will be given of a transmission system using one system each for an ISDB-S3 transmitter 12-1 assuming use of the 12 GHz band and a 21 GHz wideband transmitter 12-2 assuming use of the 21 GHz band. However, it should be noted that it is possible to further expand the transmission capacity by constructing multiple transmission systems for each of the 12 GHz band and the 21 GHz band. In the example described below, the transmitting device 11 receives an I that exceeds the maximum transmission rate that can be transmitted from the signal source device 10 by each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2. all The transmitter 11 receives data with an information bit rate of I and distributes the data to the ISDB-S3 transmitter 12-1, the 21 GHz band transmitter 12-2, and the IP network 19 based on divided frames, which will be described later with reference to FIG. ISDB-S3 For the 21 GHz transmitter 12-2, the information bit rate is I 21GHzThe remaining data that exceeds the maximum transmission rate that can be transmitted by both the ISDB-S3 transmitter 12-1 and the 21 GHz band transmitter 12-2 is distributed to the IP network 19 at the information bit rate I IP Then, the large volume of data acquired from the signal source device 10 is distributed and output.

[0040] The information bit rate of the large amount of data acquired from the signal source device 10 is I all In that case, all and the information bit rate I after distribution by the transmitting device 11 ISDB-S3 ,I 21GHz ,I IP If the measurement range of the information bit rate is limited to the actual data (payload excluding the header) of video, audio, etc. to be transmitted, the following formula (1) is established between

[0041]

number

[0042] Here, when transmitting large-capacity data acquired from the signal source device 10, the transmitting device 11 predetermines the ISDB-S3 transmitter 12-1 to be used as the 12 GHz-band satellite transmission path and the 21 GHz-band wideband transmitter 12-2 to be used as the 21 GHz-band satellite transmission path. Since the maximum transmittable value is determined by the modulation method, LDPC coding rate, and symbol rate set in each of the ISDB-3 transmitter 12-1 and the 21 GHz-band wideband transmitter 12-2, respectively, the transmitting device 11 receives TMCC (Transmission and Multiplexing Configuration Control) information (TMCC ISDB-S3 ,TMCC 21GHz ) to obtain the information bit rate I ISDB-S3 ,I 21GHzIn addition, when the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 are determined in advance to use a fixed coding modulation method and symbol rate, the information bit rate I can be set without acquiring TMCC information. ISDB-S3 ,I 21GHz can be determined.

[0043] The transmitting device 11 receives large-capacity data from the signal source device 10 at an information bit rate I all When the large amount of data can be transmitted only by the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 without using the IP network 19, the large amount of data is distributed within that range.

[0044] The ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2 transmit the information bit rate I ISDB-S3 ,I 21GHz A modulated signal based on the respective coding and modulation method is generated for each data, and the signal is uplinked to the 12 GHz band broadcasting satellite 14-1 via the 12 GHz band transmitting antenna 13-1 and to the 21 GHz band broadcasting satellite 14-2 via the 21 GHz band transmitting antenna 13-2.

[0045] The modulated signals from the ISDB-S3 transmitter 12-1 uplinked to the 12 GHz band broadcasting satellite 14-1 are simultaneously downlinked to the 12 GHz band receiving antenna 15 in the service area covered by the broadcasting satellite 14-1. Similarly, the modulated signals from the 21 GHz band transmitter 12-2 uplinked to the 21 GHz band broadcasting satellite 14-2 are simultaneously downlinked to the 21 GHz band receiving antenna 15-2 in the service area covered by the broadcasting satellite 14-2.

[0046] The ISDB-S3 receiver 16-1 receives the corresponding modulated signal from the ISDB-S3 transmitter 12-1 via the 12 GHz band receiving antenna 15-1, performs demodulation and decoding processing corresponding to the coding and modulation method in the ISDB-S3 transmitter 12-1, restores each data transmitted from the ISDB-S3 transmitter 12-1, and transmits TMCC information (TMCC ISDB-S3 ) to the receiving device 17. Similarly, the 21 GHz band wideband receiver 16-2 receives the corresponding modulated signal from the 21 GHz band wideband transmitter 12-2 via the 21 GHz band receiving antenna 15-2, performs demodulation and decoding processing corresponding to the coding modulation method and symbol rate in the 21 GHz band wideband transmitter 12-2, restores each data transmitted from the 21 GHz band wideband transmitter 12-2, and outputs the TMCC information (TMCC 21GHz ) to the receiving device 17.

[0047] In this example, the receiving device 17 receives TMCC information (TMCC ISDB-S3 ) and TMCC information obtained from the 21 GHz wideband receiver 16-2 (TMCC 21GHz ) based on the information bit rate I ISDB-S3 ,I 21GHz The receiving device 17 reconstructs divided frames, which will be described later with reference to FIG. 4, for each piece of data. The receiving device 17 also reconstructs a part of the distributed data (information bit rate I IP If there is data of the second frame, the second frame receiving unit 10 also receives the data and reconstructs the divided frames, which will be described later with reference to FIG.

[0048] The receiving device 17 receives the divided data (information bit rate I ISDB-S3 ,I 21GHz ,I IPThe signal source device 10 receives all of the data (information bit rate I all The digital signal processing unit 14 restores the digital signal (data equivalent to that transmitted via the digital signal processing unit 13) and generates an output signal suitable for the display device 18, which is then output to the display device 18.

[0049] The display device 18 reproduces the large amount of data sent from the signal source device 10 via the receiving device 17. Instead of the display device 18, a recording device for recording the large amount of data on a recording medium may be used.

[0050] The connections between the transmitting device 11 and the signal source device 10, and between the transmitting device 11 and the ISDB-S3 transmitter 12-1 and the 21 GHz band transmitter 12-2 may be direct communication by a dedicated line or may be connection via an IP-based local area network. Similarly, the connections between the receiving device 11 and the display device 18, and between the receiving device 11 and the ISDB-S3 receiver 16-1 and the 21 GHz band receiver 16-2 may be direct communication by a dedicated line or may be connection via an IP-based local area network.

[0051] The transmitting device 11 according to an embodiment of the present invention will be described in more detail below.

[0052] (Transmitting device) 2 is a block diagram showing a schematic configuration of a transmission device 11 according to an embodiment of the present invention. The transmission device 11 includes a TLV signal generation unit 111, a frame segment generation unit 112, and an IP encapsulation unit 113.

[0053] The TLV signal generator 111 receives the information bit rate I all The data input unit 112 receives large amounts of data (including video and audio), converts (stores) the data into a signal in TLV packet format (see, for example, ARIB STD-B32, Volume 3, p. 20, 3.5, TLV packet), and outputs the data to the segment frame generation unit 112.

[0054] For example, the signal source device 10 may have an information bit rate I all An example will be described in which the large volume of data is sent to the TLV signal generating unit 111 as an IP-based variable length signal (hereinafter, referred to as an "IP signal"). Such an IP signal may be, for example, an IP packet stored in an Ethernet (registered trademark) frame.

[0055] When input in the form of an IP signal, the TLV signal generator 111 determines the packet length of the variable-length IP packet obtained from the signal source device 10, generates a 4-byte TLV header conforming to the signal in the TLV packet format as shown in Fig. 3, and assigns it to the TLV packet payload. Normally, the TLV header is composed of a packet type field (one byte indicating "0x7F" and one byte indicating the type) and two bytes indicating the packet length field (length).

[0056] Here, FIG. 3 shows an example of converting the IP packet to be stored in the TLV packet payload, but the TLV signal generator 111 converts the information bit rate I all The large-capacity data may be stored in an Ethernet (registered trademark) frame, in an IP packet format, or raw data such as pure video and audio. The TLV signal generating unit 111 converts the large-capacity data acquired from the signal source device 10 in any signal format (if the data has a header, it is stored as is as shown in FIG. 3) into a TLV signal with a TLV header, thereby making it possible to limit the input signal of the divided frame generating unit 112 described later to a signal in the TLV packet format.

[0057] For example, the information bit rate I allAs shown in Fig. 3, the large-capacity data is configured as an IP packet, and in addition to the IP header and IP packet payload, other header information (e.g., UDP (User Datagram Protocol) header, etc.) may be added to the IP packet, and further, the IP packet payload may be configured with an MMT signal that constitutes an MMTP packet consisting of an MMTP header and an MMTP packet payload. In this way, the information bit rate I all If the large volume of data has a header, it is stored directly in the TLV packet payload as shown in Fig. 3. This allows for high compatibility without adversely affecting IP-based signal transmission even after passing through this transmission system 1.

[0058] Incidentally, as described below, the transmitting device 11 according to the present invention is equipped with a segmented frame generating unit 112, which not only makes it highly compatible with IP-based signal transmission, but also makes it compatible with the frame structures of the ISDB-S3 format and the 21 GHz band broadband transmission system.

[0059] The divided frame generating unit 112 determines divided frames of frame lengths conforming to independent transmission methods that apply a common error correction code (LDPC code) to a plurality of broadcast transmission paths including two types of frequency bands (ISDB-S3 12 GHz band satellite transmission path and 21 GHz band satellite transmission path) used for the bulk transmission. The divided frame generating unit 112 configures the divided frames with basic divided slots based on the maximum transmission rate of the 12 GHz band satellite transmission path among information bit rates required for transmission of predetermined data to be transmitted, and when the information bit rate required for transmission of the predetermined data exceeds the maximum transmission rate transmittable on the 12 GHz band satellite transmission path, further configures the divided frames with basic divided slots based on the ratio between the maximum transmission rate of the 21 GHz band satellite transmission path and the maximum transmission rate of the 12 GHz band satellite transmission path, and when the information bit rate exceeds the maximum transmission rate transmittable on the 12 GHz band and 21 GHz band satellite transmission paths, further configures the divided frames by adding a predetermined number of basic divided slots for transmission via the communication transmission path of the IP network 19.

[0060] Then, the fragmented frame generation unit 112 controls the connection to the ISDB-S3 transmitter 12-1 and the 21 GHz broadband transmitter 12-2, as well as the communication transmission path of the IP network 19, so as to fragment and transmit the specified data converted into a TLV packet format signal based on the constructed fragmented frame.

[0061] In this example, the two types of frequency bands are a 12 GHz band satellite transmission path for the first frequency band and a 21 GHz band satellite transmission path for the second frequency band. When constructing the divided frame, the divided frame generation unit 112 calculates the corresponding information bit rates based on the coding and modulation method of each of the multiple broadcast transmission paths, and forms basic divided slots for the multiple broadcast transmission paths by inserting nulls after the data assigned according to each information bit rate so that the frame length of the divided frame constituting each basic divided slot is a constant value. The first basic divided slot in the divided frame is assigned data for the 12 GHz band satellite transmission path, and the second basic divided slot and subsequent basic divided slots are assigned data for the 21 GHz band satellite transmission path. The remaining data exceeding the maximum rate that can be transmitted on the 12 GHz band and 21 GHz band satellite transmission paths is assigned to a predetermined number of basic divided slots for transmission via the communication transmission paths of the IP network 19.

[0062] As a specific example, the divided frame generation unit 112 configures a divided frame (see FIG. 4) for adjusting the information bit rate related to distribution to the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2, and divides the TLV signal input from the TLV signal generation unit 111 based on this divided frame to the succeeding ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2, and adjusts the information bit rate I of the TLV signal to be transmitted at a rate exceeding the maximum transmission rate that can be transmitted by the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2. all In this case, the traffic is also divided and distributed to the IP network 19.

[0063] The transmitting device 11 determines in advance which ISDB-S3 transmitter 12-1 and 21 GHz band wideband transmitter 12-2 are to be used as satellite transmission paths when transmitting large amounts of data obtained from the signal source device 10. Since the maximum transmittable value is determined by the modulation method and LDPC coding rate set in each of the ISDB-S3 transmitter 12-1 and 21 GHz band wideband transmitter 12-2, the transmitting device 11 receives TMCC information (TMCC ISDB-S3 ,TMCC 21GHz ) to obtain the information bit rate I ISDB-S3 ,I 21GHz In addition, when the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2 are determined in advance to use a fixed coding and modulation method, the information bit rate I ISDB-S3 ,I 21GHz For the remaining data exceeding the maximum transmission rate that can be transmitted by the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2, the information bit rate I IP Then, the large volume of data acquired from the signal source device 10 is distributed.

[0064] As shown in Fig. 4, the divided frame generated by the divided frame generating unit 112 has a horizontal width corresponding to the frame length and a vertical width corresponding to the number of divided slots, and this divided frame is composed of a plurality of basic divided slots. The frame length of each basic divided slot corresponds to the transmission frame length of ISDB-S3 (120 slots of ISDB-S3), and is set to be easily synchronized with the ISDB-S3 transmitter 12-1 (synchronized with the transmission frame 120 slots of ISDB-S3), and to be able to accommodate the coding and modulation method at the maximum transmission rate supported by ISDB-S3 (32APSK (LDPC coding rate: 9 / 10) in the example of ISDB-S3). That is, based on the specifications of ISDB-S3, the transmission frame length of each basic divided slot is set to 120 x 40392 bits = 4847040 bits (605880 bytes).

[0065] As shown in Fig. 4, the first basic division slot #1 is preferentially assigned to the ISDB-3 transmitter 12-1, and the second basic division slot #2 and onwards are assigned to the 21 GHz band wideband transmission device 12-2. For the remaining data that exceeds the maximum rate that can be transmitted by the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmission device 12-2, the last basic division slot #n is assigned to the IP network. Therefore, the area of ​​the basic division slot #1 that can be input to the ISDB-S3 transmitter 12-1, excluding NULL (ISDB-S3) included in the basic division slot #1, is assigned to the IP network. ISDB-S3 Next, the area that can be input to the 21 GHz wideband transmitter 12-2, excluding NULL (21 GHz) included in the basic division slot #n-1, among the basic division slots #2 to #n-1, is assigned as I 21GHz The number of basic division slots (n-2) that can be accommodated by the 21 GHz wideband transmitter 12-2 is uniquely determined by the modulation method, coding rate, and symbol rate set in the 21 GHz wideband transmitter 12-2. Also, NULL (ISDB-S3) and NULL (21 GHz) are stuff bits that serve as adjustment bits that are uniquely determined by the modulation method, coding rate, and symbol rate determined by the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2, respectively. Next, when the final basic division slot #n is applied, the area excluding NULL (IP) included in the basic division slot #n is assigned as I IP NULL (IP) is a stuff bit that serves as an adjustment bit to facilitate synchronous synthesis between basic divided slots.

[0066] The TLV signal input to the segment frame generating unit 112 is accommodated in the basic segment slot #1 through #n in ascending order, with a 4-byte TLV header and a variable-length TLV packet payload. Here, the TLV signal in the basic segment slot #1 is for the ISDB-S3 transmitter 12-1, the TLV signals in the basic segment slots #2 through #n-1 are for the 21 GHz wideband transmitter 12-2, and the TLV signal in the basic segment slot #n is for transmission via the IP network 19. However, in order to insert NULL (ISDB-S3) and NULL (21 GHz) after the basic segment slots #1 and #n-1, respectively, the head TLV header is always inserted at the head positions of the basic segment slots #2 and #n. This facilitates synchronous synthesis of segment slots in a frame during segment transmission among a plurality of transmission paths, such as 12 GHz band transmission, 21 GHz band transmission, and IP transmission.

[0067] For the above reasons, among the basic division slots, for basic division slot #1 input to the ISDB-S3 transmitter 12-1, basic division slot #2 corresponding to the first slot of the basic division slot input to the 21 GHz wideband transmitter 12-2, and basic division slot #n input to the IP network, the first byte "0x7F" of the TLV header in each TLV packet constituting the TLV signal is used as a pattern to determine the start position of the TLV packet in the broadcast transmission path.

[0068] Therefore, the TLV packets (first TLV packets) arranged at the beginning of the basic division slots #1, #2, and #n clearly indicate the beginning position of the TLV signal in the basic division slot, as shown in Fig. 5. Fig. 5 is a configuration diagram of the first TLV packet related to the divided frame used in the transmitting device 11 of one embodiment according to the present invention. As the packet type field at the beginning position of the basic division slots #1, #2, and #n, an identification pattern indicating the beginning TLV packet of each basic division slot in each divided frame is set from "0x04-0xFD", which is an undefined area in the existing TLV signal format. Therefore, the first TLV packets shown in Figs. 4 and 5 are set to a packet type field value different from other TLV packets set by default, so that the receiving device 17 can identify which divided frame the TLV packet indicates the beginning of the basic division slots #1, #2, and #n.

[0069] In particular, the divided frame generation unit 112 in the transmitting device 11 of this embodiment has a means for adding identification information to the beginning of the basic divided slots for each transmission path that constitutes the divided frames to be assigned to the first frequency band broadcast transmission path (12 GHz band satellite transmission path as ISDB-S3), the second frequency band broadcast transmission path (21 GHz band satellite transmission path), and the communication transmission path (IP network 19) to uniquely indicate the signal order of the divided frames, and a means for using an LDPC code as a common error correcting code and adjusting the number of TLV packets that can be accommodated in each basic divided slot, the number of divisions of the basic divided slot, and the NULL length according to the coding rate of the LDPC code in order to input signals in TLV packet format to both the 12 GHz band satellite transmission path and the 21 GHz band satellite transmission path without excess or deficiency.

[0070] Fig. 6 is a diagram showing an example in which the numerical value of the packet type field in the head TLV packet is incremented within a predetermined range as identification information for uniquely indicating the signal order of the segmented frame in basic segmented slots #1, #2, and #n among the basic segmented slots constituting the segmented frame in the transmitting device 11 according to an embodiment of the present invention. As shown in Fig. 6, the segmented frame generating unit 112 increments and assigns the numerical value of the packet type field in the head TLV packet of basic segmented slots #1, #2, and #n from "0x04" (initial value), and assigns the identification information to each basic segmented slot by repeating the increment within the range of "0x04"-"0xFD".

[0071] More specifically, in the leftmost divided frame shown in FIG. 6, when "0x04" is added to the packet type field in the head TLV packet of the basic divided slots #1, #2, and #n, "0x05" is added to the corresponding position of the next divided frame, and "0x06" is added to the corresponding position of the next divided frame. That is, a value incremented by 1 is added to the packet type field in the head TLV packet of the basic divided slots #1, #2, and #n for each divided frame, and "0x04" is added to the next divided frame of the divided frame to which "0xFD" is added, and this is repeated. This makes it possible to identify the relationship between the basic divided frames even if the reception order of the divided frames in the receiving device 17 is switched with the transmission order on the transmitting device 11 side. Also, the receiving device 17 can rearrange the divided frames into the correct order, and can link the divided frames to the basic divided slots.

[0072] As described above, as shown in FIG. 4, the basic division slot #1 is configured to receive the TMCC information (TMCC ISDB-S3), a null (NULL (ISDB-S3)) is inserted from the rear of basic division slot #1 to fill the remaining area where the information bit rate has been adjusted. This null may be a variable-length null TLV packet (a variable-length packet with "0xFF" as the basic unit) to clarify the unit of each TLV packet in the division frame, but it is not actually transmitted on the broadcast transmission path.

[0073] There are 55 types of combinations of modulation method and LDPC coding rate supported by ISDB-S3, and although this is not limited to this, for example, if it is determined that data transmission is performed by a single modulation method and coding modulation method using LDPC code in the ISDB-S3 transmitter 12-1, there are also 55 types of null (NULL(ISDB-S3)) lengths as shown in Fig. 7. Fig. 7 is a diagram illustrating the relationship between the ISDB-S3 modulation method, LDPC coding rate, payload size of the basic division slot, and the length of the null TLV packet to be inserted (NULL(ISDB-S3)).

[0074] Next, as shown in FIG. 4, when basic division slots #2 to #n-1 are allocated, the TMCC information (TMCC 21GHz ) based on the information bit rate (I 21GHz) and determines the number of basic divided slots (n-2) to be assigned to the 21 GHz wideband transmitter 12-2. Here, the transmission symbol frame configuration in the 21 GHz wideband transmitter 12-2 is shown in Fig. 8. As shown in Fig. 8, after the header of the first 26 symbols, a phase reference burst signal of X symbols is repeated every 187 symbols of the main signal. The main signal symbol length is 22,440 symbols in the case of QPSK and 14,960 symbols in the case of 8PSK, which is a symbol length that is consistent with modulating the 44,880-bit error correction code. The error correction code of the 21 GHz wideband transmitter 12-2 is the same as that of ISDB-S3, and the error correction code length is 44,880 bits as shown in Fig. 9. The ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 have different transmission frame configurations, but the error correction code length is the same, so packet matching can be achieved without excess or deficiency in many combinations of modulation methods and coding rates with the basic division slots based on the ISDB-S3 transmission frame. Therefore, from the transmission symbol frame configuration shown in Figure 8, the information bit rate I 21GHz is calculated by equation (2) for QPSK and equation (3) for 8PSK. In equations (2) and (3), Rs corresponds to the symbol rate, X corresponds to the phase reference burst signal length, and k / 44,880 corresponds to the coding rate (see Figure 10 for the TLV packet payload length k).

[0075]

number

[0076]

number

[0077] According to equations (2) and (3), the information bit rate I 21GHz is uniquely determined by the modulation method, coding rate, symbol rate, and phase reference burst signal length specified by the 21 GHz wideband transmitter 12-2.

[0078] Next, the basic division slot number (n-2) is calculated based on the formula (4). ISDB-S3 ) corresponds to the maximum transmission bit rate of ISDB-S3 (146.6735 Mbps). Also, ceil() is a function that rounds up the value in () to the nearest whole number.

[0079]

number

[0080] As an example of the transmission symbol frame configuration shown in Fig. 8, when the modulation method is 8PSK, the symbol rate is 275Mbaud, the coding rate is 9 / 10, and the phase reference burst signal length X=12, 21GHz = 696.5 Mbps, in this case, n-2 = 5 slots. The basic division slot #1 allocated to the ISDB-S3 transmitter 12-1 is based on 32APSK (9 / 10) 120 slots. In other words, the constituent unit of this divided frame, 605880 bytes = 4847040 bits, has a relationship of 4847040 = 120 × 40392 in relation to k = 40392 bits at a coding rate of 9 / 10, so it corresponds to 120 packets when the LDPC code in FIG. 9 is considered as one packet. Based on the above, the number of error correcting code packets (number of LDPC packets) P ​​that can be accommodated in the basic division slot allocated to the 21 GHz wideband transmitter 12-2 is 21GHz is calculated using formula (5), where round() is a function that rounds the value in parentheses to the nearest integer.

[0081]

number

[0082] As an example of the transmission symbol frame configuration shown in FIG. 8, the I 21GHz , n-2 and P 21GHz is shown in FIG. 11. In this example, for all coding rates, P21GHz = 360, but as the coding rate increases, I 21GHz 8 is applied, that is, the transmission symbol time of the 21 GHz band transmitter 12-2 when transmitting 360 LDPC packets at a symbol rate of 250 Mbaud is approximately 33 msec, which coincides with the transmission symbol time of the basic division slot #1 connected to the ISDS-B3 transmitter 12-1. Therefore, when this transmission symbol frame configuration is applied, it is possible to make the transmission times between the 12 GHz band and the 21 GHz band transmitting / receiving devices the same.

[0083] The packet allocation configurations of the basic division slots for each LDPC coding rate (1 / 2 to 9 / 10) input to the 21 GHz wideband transmitter 12-2 based on Fig. 11 are shown in Fig. 12 to Fig. 19. Note that, in the coding rates of 3 / 4, 5 / 6 and 7 / 8 shown in Fig. 15, Fig. 17 and Fig. 18, respectively, k (TLV packet payload length) is not an integer multiple of 605880 bytes (basic division slot length), so NULL (21 GHz) is inserted after each basic division slot. At this time, it is possible to allocate less NULL (21 GHz) in each basic division slot by adjusting the TLV packets in each basic division slot to be packed or divided, but such adjustment not only complicates the process, but also has the risk of error propagation that cannot be corrected to other adjusted TLV packets when an error that cannot be corrected occurs in any TLV packet in each adjusted basic division slot. Therefore, it is desirable to insert NULL (21 GHz) in each basic division slot at coding rates of 3 / 4, 5 / 6, and 7 / 8 shown in Figures 15, 17, and 18, respectively. And, basically, in the final basic division slot (#n-2) connected to the 21 GHz wideband transmitter 12-2, a NULL (NULL (21 GHz)) is inserted from the rear to fill the remaining area where the information bit rate is adjusted. However, when k (TLV packet payload length) is an integral multiple of 605880 bytes (basic divided slot length), such as the examples of coding rates 3 / 5 and 9 / 10 shown in Figures 13 and 19, respectively, it is not necessary to insert NULL (21 GHz). This NULL may be a variable-length NULL TLV packet (variable-length packet with "0xFF" as the basic unit) to clarify the unit of each TLV packet in the divided frame, but it is not actually transmitted on the broadcast transmission path.

[0084] As can be seen from Fig. 4, when data is divided and transmitted via a communication transmission path (IP network 19), a basic division slot having a head TLV packet is configured in one divided frame, as in the case of dividing and transmitting data via a broadcast transmission path. Therefore, without providing a separate frame header for one divided frame, the receiving device 17 can reconstruct each divided frame using each head TLV packet, and this is a form that is highly compatible with both broadcast transmission paths and communication transmission paths, and also has high transmission efficiency. Similarly, in the basic division slot #n in the communication transmission path, nulls (NULL(IP)) are inserted from the rear to fill the remaining area after the information bit rate is adjusted. This null may be a variable-length null TLV packet (a variable-length packet with "0xFF" as the basic unit) to clarify the unit of each TLV packet in the divided frame, but it is not actually transmitted on the communication transmission path.

[0085] In this manner, in the example shown in FIG. 2, the divided frame generating unit 112 constructs a divided frame (see FIG. 4) for adjusting the information bit rate related to distribution to the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2 at appropriate times based on the TMCC information, divides the TLV signal input from the TLV signal generating unit 111 based on this divided frame to the succeeding ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2, and adjusts the information bit rate I , which is the information bit rate I , that exceeds the maximum transmission rate that can be transmitted by the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2. all In this case, the traffic is also divided and distributed to the IP network 19.

[0086] The divided frame generation unit 112 operates to distribute large volumes of data in divided frame units to the ISDB-S3 transmitter 12-1, the 21 GHz wideband transmitter 12-2, and the IP network 19, so that the distribution operation is stabilized when performed in clock synchronization, and since the payload size that can be accommodated in the transmission frames (ISDB-S3 and 21 GHz wideband transmission symbol frames (see Figure 8)) in each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 matches the payload size of the basic divided slot, connection to the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 is easy.

[0087] In addition, even if the coding and modulation methods in the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 are different and variable, the divided frame generation unit 112 can set the payload size of each corresponding basic divided slot based on the TMCC information acquired from each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2, so that the information bit rate for each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 can be controlled to be constant. In other words, the information bit rate of the basic divided slot is determined based on the TMCC information of each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2.

[0088] As an example, Fig. 20 shows a configuration example of a basic division slot in which the coding and modulation method supported by the ISDB-S3 transmitter 12-1 is set to 16APSK (LDPC coding rate: 7 / 9) and the coding and modulation method supported by the 21 GHz wideband transmitter 12-2 is set to QPSK (LDPC coding rate: 2 / 3). In the example shown in Fig. 20, it is possible to transmit 99.9552 Mbps in #1 and 325.9 Mbps in #2 to #4 per basic division slot. Note that the null (or null TLV packet) in the basic division slot is a padding-like function for facilitating connection between the transmitting device 11 and the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 and for facilitating clock synchronization management, and is therefore not actually transmitted from the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 on the broadcast transmission path.

[0089] As shown in FIG. 2, when the number of data distributions to the ISDB-S3 transmitter 12-1, the 21 GHz wideband transmitter 12-2, and the IP network 19 is made variable in accordance with the TMCC information (i.e., when the total number of basic divided slots constituting one divided frame is made variable), the divided frame generation unit 112 notifies each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 of the number of slot divisions (n ​​in this example) and the unique numbers (1, 2 to n-1, n in this example) indicating the basic divided slots corresponding to each transmitter, and generates the TMCC information (TMCC ISDB-S3 ,TMCC 21GHz ) from the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2 to the receiving device 17. This allows the receiving device 17, which will be described later in detail, to easily reconstruct one divided frame.

[0090] The information on the number of slot divisions notified to all of the ISDB-S3 transmitters 12-1 and 21 GHz wideband transmitters 12-2 to be used corresponds to the information on the total number (n) of basic divided slots in the divided frame shown in Fig. 4. The unique numbers (1, 2 to n-1, n in this example) indicating the basic divided slots notified to each of the ISDB-S3 transmitters 12-1 and 21 GHz wideband transmitters 12-2 correspond to the unique numbers identifying each basic divided slot shown in Fig. 4.

[0091] In the example shown in FIG. 2, the divided frame generating unit 112 embeds information on the number of slot divisions (n ​​in this example) and unique numbers (1, 2 to n-1, n in this example) indicating the basic divided slots corresponding to each transmitter 12 in the extension area of ​​the TMCC information acquired from each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2, and notifies them by returning the information. ISDB-S3 allows 3614 bits to be used as the extension area of ​​the TMCC information, and has a sufficient free area for independently transmitting information on the number of slot divisions and unique numbers of the basic divided slots. Also, in the 21 GHz wideband transmitter 12-2, as shown in FIG. 8, it is possible to multiplex TMCC information on the phase reference burst signal. However, the information on the number of slot divisions and unique numbers of the basic divided slots may be notified from the divided frame generating unit 112 to each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 via a local area network, or may be embedded in each basic divided slot.

[0092] For example, when it is determined that data is to be transmitted in the MMT signal format in the TLV packet payload as shown in FIG. 3, information on the number of slot divisions and the unique number of the basic division slot may be embedded in the MMTP header. In the case of MMT, an extension area is secured in the MMTP header, and it is also possible to notify information on the number of slot divisions and the unique number of the basic division slot by using the extension area. In this way, when it is determined that a signal format having unique header information such as MMT is to be stored, the information is notified by using the free area of ​​the header information. In addition, since it is difficult to imagine that the number of slot divisions will be changed frequently, information on the number of slot divisions and the unique number of the basic division slot scheduled at the transmission time for unique information such as the frequency allocation of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 can be determined and known in advance between the transmitter and receiver (the transmitter 11 and the receiver 17), or it is also possible to notify the receiver 17 in advance before the transmission of the large volume of data.

[0093] The IP encapsulation unit 113 shown in FIG. IP When distributing and transmitting large amounts of data obtained from the signal source device 10, header information conforming to an Internet protocol such as IPv4 or IPv6 is added to the TLV signal in the basic division slot #n shown in Figure 4, and IP encapsulation is performed to form an IP-based signal (IP packet, Ethernet (registered trademark) frame, etc.), which is output to the IP network 19 and transmitted to the receiving device 17 via the IP network 19.

[0094] In particular, when the fragmented frame constructed by the fragmented frame generation unit 112 includes a predetermined number of basic fragmented slots for transmission via the communication transmission path of the IP network 19, the IP encapsulation unit 113 has means for dividing this predetermined number of basic fragmented slots into IP-based packets that are consistent with the IP network 19, and for assigning an IP sequence number to each of the divided IP-based packets to uniquely indicate the signal order of the packets, and transmitting the divided IP-based packets to the receiving device 17.

[0095] Fig. 21 is a diagram showing a packet structure including an IP sequence number that is assigned for division and transmission of an IP-based packet when a basic division slot using transmission via an IP network is included in a divided frame in the transmitting device 11 of an embodiment according to the present invention. As shown in Fig. 21, since reordering of IP-based packets occurs on the IP network, the IP encapsulating unit 113 assigns a 16-bit IP sequence number (IPSN) to the IP payload area and transmits the packets to the receiving device 17. By using this IP sequence number on the receiving device 17 side, the receiving device 17 can rearrange the reordered IP-based packets into an appropriate order.

[0096] The receiving device 17 rearranges the received IP-based signals based on the header information, and then extracts the TLV signal in the basic division slot #n shown in Fig. 4. However, as described above, the transmitting device 11 does not receive the information bit rate I, which exceeds the maximum transmission rate that can be transmitted from the signal source device 10 by the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2. all The transmission to the IP network 19 is used only when transmitting the data to the receiving device 17. The basic divided slot #n shown in Fig. 4 may be not limited to one slot but may be multiple slots, but in this embodiment, the basic divided slot #n is set to one slot because the configuration mainly uses a broadcast transmission path with high stability of transmission time. In addition, when dividing and transmitting large capacity data from the transmitting device 11 to the receiving device 17 using the broadcast transmission path and the communication transmission path, the basic divided slot is set to the same size as the size of the basic divided slot for transmission by the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 from the viewpoint of easiness of reconstructing the divided slot (connecting the TLV packets in each basic divided slot) on the receiving device 17 side.

[0097] As described above, the transmission device 11 of the embodiment shown in FIG. 2 notifies each of the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 of the slot division number and the unique number (1, 2 to n-1, n in this example) indicating the basic divided slot corresponding to each transmitter 12 by the divided frame generation unit 112, and transmits the TMCC information (TMCC ISDB-S3 ,TMCC 21GHz ) to transmit from the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 to the receiving device 17. For this reason, the receiving device 17 according to an embodiment of the present invention corresponding to the transmitting device 11 shown in FIG. 2 will be described in detail below.

[0098] (Receiving device) 22 is a block diagram showing a schematic configuration of a receiving device 17 according to an embodiment of the present invention. The receiving device 17 includes a frame segment reconstructing section 171, an IP decapsulating section 172, and an output signal generating section 173.

[0099] The divided frame reconstructing unit 171 converts the TMCC information (TMCC ISDB-S3 ,TMCC 21GHz ) based on the information in the TLV header, the head TLV packet constituting each basic divided slot is identified and rearranged, and the information bit rate I ISDB-S3 ,I 21GHz ,I IPFor each data, null (or a null TLV packet) is inserted at the end of each basic divided slot to reconstruct the divided frame described above with reference to Fig. 4. Note that in this example, the number of slot divisions for reconstructing the divided frame shown in Fig. 4 and information on the unique number indicating the basic divided slot corresponding to each transmitter 12 are stored in the TMCC information (TMCC ISDB-S3 ,TMCC 21GHz However, when the coding and modulation methods used in a plurality of broadcast transmission paths are known in advance, and when the number of data distributions to the ISDB-S3 transmitter 12-1, the 21 GHz band wideband transmitter 12-2, and the IP network 19 is fixed and not variable, or when the information is scheduled or notified in advance so that it is known in advance between the transmitter and the receiver, the divided frame reconstructing unit 171 uses the TMCC information (TMCC ISDB-S3 ,TMCC 21GHz ), it is possible to reconstruct the divided frames having a fixed frame length in advance without needing to refer to the frame length.

[0100] In addition, when the divided frame reconstructing unit 171 receives a signal in the TLV packet format transmitted from the ISDB-S3 transmitter 12-1 and the 21 GHz band wideband transmitter 12-2 via both the 12 GHz band satellite transmission path and the 21 GHz band satellite transmission path, the divided frame reconstructing unit 171 adjusts the number of TLV packets that can be accommodated in each basic divided slot, the number of divisions of the basic divided slots and the NULL length in accordance with the coding rate of the LDPC code based on the number of basic divided slots calculated by the ratio of the information bit rate that can be transmitted on the 21 GHz band satellite transmission path to the maximum bit rate of the 12 GHz band satellite transmission path, and reconstructs a divided frame consisting of the predetermined number of basic divided slots.

[0101] That is, the frame segment reconstructing unit 171 can distinguish the head TLV packet shown in FIG. 5 from the setting in the TLV header and can determine the identification information for uniquely indicating the signal order of the frame segment (in the above embodiment, the numerical value of the packet type field in the head TLV packet) to distinguish it from other TLV headers and grasp the head position of each basic segment slot and the appropriate signal order between the frame segment. The frame segment reconstructing unit 171 then determines the TLV packet arrangement at the information bit rate corresponding to each basic segment slot from the slot division number for reconstructing the frame segment shown in FIG. 4 and the information of the unique number indicating the basic segment slot corresponding to each transmitter 12, and reconstructs the frame segment shown in FIG. 4 by inserting a predetermined amount of nulls (or null TLV packets) after each basic segment slot. As a result, the frame segment is accurately restored using nulls (or null TLV packets) that are not actually transmitted on the broadcast transmission path and the communication transmission path, so that the processing speed between each basic segment slot in each frame segment can be kept constant and the processing can be stabilized, and the transmission delay on the broadcast transmission path and the communication transmission path can be compensated for. In addition, since the head TLV packet can be used to grasp the head position of each basic divided slot, the receiving device 17 can reconstruct each divided frame using each head TLV packet without providing a separate frame header, resulting in high transmission efficiency and compatibility with both broadcast transmission paths and communication transmission paths.

[0102] The IP decapsulation unit 172 decapsulates a part of the distributed data (information bit rate I IP 4. If there is data (data (a) above), the data is also received in an IP-based packet and IP decapsulated, and the signal order is aligned based on the IP sequence number for uniquely indicating the signal order assigned to the packet. Then, the TLV signal in the basic segmentation slot #n shown in FIG. 4 is extracted, the basic segmentation slot #n is reconstructed, and the result is output to the segmented frame reconstruction unit 171.

[0103] As a result, the divided frame reconstructing unit 171 reconstructs the divided part of the data (information bit rate I IP If there is data, that data is also received and rearranged to reconstruct the segment frame described above with reference to FIG. 4 based on the above-mentioned identification information (in the above embodiment, based on the numerical value of the packet type field in the first TLV packet).

[0104] The output signal generation unit 173 concatenates (i.e., concatenates valid data) the data from basic division slot #1 to basic division slot #n in the segment frame reconstructed by the segment frame reconstruction unit 171 in ascending order of each basic division slot after deleting TLV headers (including the first TLV header) and nulls, and generates large-capacity data (information bit rate I all The digital signal processing unit 12 restores the digital data (data equivalent to that transmitted via the digital signal processing unit 12) and generates an output signal suitable for the display device 18, which is then output to the display device 18. Note that instead of the display device 18, a recording device for recording large amounts of data on a recording medium may be used.

[0105] As described above, the transmission system 1 including the transmitting device 11 and the receiving device 17 according to the present invention is configured to divide large-capacity data in the TLV packet format and transmit the data in bulk. The transmitting device 11 then determines divided frames having a frame length conforming to a common transmission method for a plurality of broadcast transmission paths used for the bulk transmission. In particular, when the information bit rate required for transmitting the large-capacity data falls within the maximum transmission rate of the plurality of broadcast transmission paths, the transmitting device 11 configures the divided frames with a number of basic divided slots corresponding to the plurality of broadcast transmission paths, and when the information bit rate required for transmitting the large-capacity data exceeds the maximum transmission rate that can be transmitted through the plurality of broadcast transmission paths, the transmitting device 11 further configures the divided frames by adding a predetermined number of basic divided slots for transmission via the communication transmission path of the IP network 19. The transmitting device 11 then controls the ISDB-S3 transmitter 12-1 and the 21 GHz wideband transmitter 12-2 in the plurality of broadcast transmission paths, and the connection to the communication transmission path (IP network 19) so as to divide and transmit the large-capacity data converted into the TLV packet format signal based on the divided frames. In addition, the transmitting device 11 assigns identification information (in the above embodiment, based on the numerical value of the packet type field in the first TLV packet) for uniquely indicating the signal order of the divided frames to each basic divided slot constituting the divided frames. This stabilizes the information bit rate related to the transmission of the large amount of data, facilitates and stabilizes the data transmission synchronization between the transmitting device 11 and the receiving device 17, improves the ease of connection (ease of synchronization of connection timing) to the broadcast transmission path and the communication transmission path to be used, and enables the receiving device 17 to appropriately return the signal order to the original order even when the signal order is changed due to reordering or the like. In particular, since the transmission method of the 12 GHz band broadcast transmission path is the ISDB-S3 method, the basic divided slot constituting the divided frames has a frame length corresponding to 120 slots of ISDB-S3.

[0106] Furthermore, the transmitting device 11 according to the present invention determines in the TLV header the head TLV packet indicating the head TLV packet in each basic division head slot input to the ISDB-S3 transmitter 12-1, the 21 GHz wideband transmitter 12-2, and the communication transmission path that constitute the divided frame, so as to distinguish it from other TLV packets in each basic division slot, and configures the divided frame so that the receiving device 17 can identify which TLV packet indicates the head of which basic division slot in which divided frame. The receiving device 17 according to the present invention then identifies the head TLV packet based on the setting information in the TLV header of the TLV packet format signal received via the multiple broadcast transmission paths and the communication transmission path, identifies which TLV packet indicates the head of which basic division slot in which divided frame, and reconstructs the divided frame. As a result, the receiving device 17 can reconstruct each divided frame using each head TLV packet without providing a separate frame header, and the transmission efficiency is high in a manner that is highly compatible with both the broadcast transmission path and the communication transmission path.

[0107] Furthermore, when constructing or reconstructing the divided frames, the transmitting device 11 and the receiving device 17 according to the present invention calculate the corresponding information bit rate based on the coding and modulation method of each of the multiple broadcast transmission paths, and insert nulls after the data assigned according to the information bit rate of each broadcast transmission path so that the frame length of the divided frames constituting each basic divided slot is a constant value, thereby forming basic divided slots for the multiple broadcast transmission paths and basic divided slots for the communication transmission path in accordance with the multiple broadcast transmission paths. The coding and modulation method of each of the multiple broadcast transmission paths can be grasped from TMCC information used for transmission control of each of the multiple broadcast transmission paths. As a result, the transmission method used for the 12 GHz band broadcast transmission path is ISDB-S3, and the transmission format for the 21 GHz band broadcast transmission is also a format conforming to this ISDB-S3, so there are 55 types of coding and modulation methods.In the conventional technique, however, it was necessary to perform independent clock synchronization control according to the 55 types of coding and modulation methods when dividing data.However, with the transmitting device 11 and receiving device 17 of the present invention, such independent clock synchronization control is no longer necessary, and it is possible to stabilize the processing by keeping the processing speed between each basic division slot in each division frame constant, and it is possible to compensate for the transmission delay in the broadcast transmission path and the communication transmission path.

[0108] Furthermore, the transmitting device 11 according to the present invention has a means for changing the number of slot divisions of the basic divided slots constituting the divided frame when dividing and bulk transmitting large-capacity data in the TLV packet format, and for notifying the receiving device 17 of the slot division number of the basic divided slots constituting the divided frame and the unique number of each basic divided slot. Since it is difficult to imagine that the number of slot divisions will be changed frequently, it is possible to predetermine and make known between the transmitting device 11 and the receiving device 17 the information of the slot division number and the unique number of the basic divided slot scheduled at the transmission time for unique information such as the frequency allocation of each transmitter 12, but it is effective to configure the transmitting device 11 to notify the receiving device 17 in advance before transmitting the large-capacity data.

[0109] In addition, it is preferable that the transmitting device 11 according to the present invention embeds information on the number of slot divisions of the basic divided slots constituting the divided frame and the unique number of each basic divided slot in TMCC information used for transmission control of each of the multiple broadcast transmission paths, and notifies the receiving device 17. That is, although it is possible to embed the information in each basic divided slot, or in header information of a predetermined signal format (MMT, etc.) stored in a TLV packet in each basic divided slot, a configuration in which the information is embedded in the TMCC information and notified to the receiving device 17 is more convenient.

[0110] Furthermore, when constructing the divided frame, if the divided frame includes a predetermined number of basic divided slots for transmission via a communication transmission path of an IP network, the transmitting device 11 according to the present invention divides the predetermined number of basic divided slots into IP-based packets that are consistent with the IP network 19, assigns IP sequence numbers for uniquely indicating the signal order of the divided packets, and transmits the packets to the receiving device 17. When the receiving device 17 according to the present invention receives each divided IP-based packet for the predetermined number of basic divided slots transmitted via a communication transmission path of an IP network, the receiving device 17 decapsulates the packets, arranges the signal order based on the IP sequence numbers for uniquely indicating the signal order assigned to the packets, and then extracts the TLV signal to reconstruct the predetermined number of basic divided slots. This allows the receiving device 17 to properly restore the signal order to the original order even when the signal order of each IP-based packet is changed due to reordering or the like.

[0111] With regard to the above-mentioned embodiment, a computer that functions as the transmitting device 11 or the receiving device 17 can be configured, and a program for making each means of the transmitting device 11 or the receiving device 17 function can be suitably used. Specifically, a control unit for controlling each means can be configured with a central processing unit (CPU) in a computer, and a storage unit for appropriately storing a program required for operating each means can be configured with at least one memory. That is, the function of each of the above-mentioned means can be realized by having the CPU execute the program in such a computer. Furthermore, a program for making each of the means function can be stored in a predetermined area of ​​the above-mentioned storage unit (memory). Such a storage unit can be configured with a RAM or ROM inside the device, or can be configured with an external storage device (for example, a hard disk). Moreover, such a program can be configured as a part of software (stored in a ROM or an external storage device) on an OS used by the computer. Furthermore, a program for making such a computer function as each means can be recorded on a computer-readable recording medium. Moreover, each of the above-mentioned means can be configured as a part of hardware or software, and can be realized by combining each of them.

[0112] The above-mentioned embodiment has been described as a representative example, but it is clear to those skilled in the art that many modifications and substitutions can be made within the spirit and scope of the present invention. For example, in the above-mentioned embodiment, a satellite transmission path of the ISDB-S3 transmission method is used as a broadcast transmission path, but it is also possible to use a terrestrial transmission path of the next generation 4K / 8K, etc., which is expected to have a transmission frame structure similar to that of the ISDB-S3 method, as a broadcast transmission path. In addition, in the above-mentioned embodiment, a form in which the transmitting device 11, the ISDB-S3 transmitter 12-1, and the 21 GHz band wideband transmitter 12-2 are separately provided is described, but the transmitting device 11 may be provided so as to include a plurality of ISDB-S3 transmitters 12-1 and 21 GHz band wideband transmitters 12-2. Therefore, the present invention should not be interpreted as being limited by the above-mentioned embodiment, but is limited only by the scope of the claims.

[0113] Although the present invention has been described above by taking specific embodiments, the present invention is not limited to the above-mentioned embodiments and can be modified in various ways without departing from the technical concept of the present invention. For example, in the above-mentioned embodiments, a satellite transmission path is mainly used as the broadcast transmission path, but a terrestrial transmission path may be used as the broadcast transmission path. [Industrial Applicability]

[0114] According to the present invention, even in an environment where the frequency of the broadcast transmission path is constrained, it is possible to increase the overall transmission capacity related to data transmission and realize a transmission system that is highly compatible with IP. Therefore, the present invention is useful for a transmission system that divides large volumes of data using multiple types of digital modulation methods and time-division multiplexes them. [Explanation of symbols]

[0115] 1. Transmission System 10 Signal source device 11 Transmitting device 12-1 ISDB-S3 transmitter 12-2 21GHz wideband transmitter 13-1 ISDB-S3 Transmitting Antenna 13-2 21GHz band transmitting antenna 14-1 12GHz band broadcasting satellite 14-2 21GHz band broadcasting satellite 15-1 12GHz band receiving antenna 15-2 21GHz band receiving antenna 16-1 ISDB-S3 Receiver 16-2 21GHz wideband receiver 17 Receiving device 18 Display device 19 IP Networks 111 TLV signal generation section 112 Split frame generator 113 IP Encapsulation Section 171 Split frame reconstruction unit 172 IP Decapsulation Unit 173 Output signal generator

Claims

1. A transmitting device that transmits predetermined data in bulk in a TLV (Type Length Value) packet format using a plurality of broadcast transmission paths, a TLV signal generating means for inputting predetermined data to be the subject of bulk transmission from a signal source device and converting the data into a signal in a TLV packet format; a divided frame generating means for controlling each transmitter in the plurality of broadcast transmission paths and a connection to the communication transmission paths to divide and transmit the predetermined data converted into the TLV packet format signal based on the divided frames, the divided frames being configured with a basic divided slot based on a maximum transmission rate of the broadcast transmission path of a first frequency band among information bit rates required for transmitting the predetermined data, and when the information bit rate required for transmitting the predetermined data exceeds a maximum transmission rate transmittable on the broadcast transmission path of the first frequency band among the plurality of broadcast transmission paths, the divided frames being configured with a basic divided slot based on a ratio between a maximum transmission rate of the broadcast transmission path of a second frequency band among the plurality of broadcast transmission paths and a maximum transmission rate of the broadcast transmission path of the first frequency band, and when the information bit rate exceeds a maximum transmission rate transmittable on the broadcast transmission paths of the first frequency band and the second frequency band, the divided frames being configured with a basic divided slot based on a ratio between a maximum transmission rate of the broadcast transmission path of a second frequency band among the plurality of broadcast transmission paths and a maximum transmission rate of the broadcast transmission path of the first frequency band, and when the information bit rate exceeds a maximum transmission rate transmittable on the broadcast transmission paths of the first frequency band and the second frequency band, the divided frames being configured with a predetermined number of basic divided slots for transmission via a communication transmission path of an IP (Internet Protocol) network, The divided frame generating means is characterized in that it has: a means for adding identification information to the beginning of a basic divided slot for each transmission path that constitutes the divided frame assigned to the broadcast transmission path of the first frequency band, the broadcast transmission path of the second frequency band, and a communication transmission path, for uniquely indicating the signal order of the divided frame; and a means for using an LDPC code as a common error correcting code to input the TLV packet format signal to both the broadcast transmission path of the first frequency band and the broadcast transmission path of the second frequency band without excess or deficiency, and adjusting the number of TLV packets that can be accommodated in each basic divided slot, the number of divisions of the basic divided slot, and the NULL length according to the coding rate of the LDPC code.

2. The transmitting device described in claim 1, characterized in that the divided frame generating means determines in a TLV header a setting such that a first TLV packet indicating a first TLV packet of each basic divided first slot constituting the divided frame assigned to each transmission path of the first frequency band, the second frequency band, and the communication transmission path constituting the divided frame is distinguished from other TLV packets in each basic divided slot, and constructs the divided frame so that a receiving side can identify which TLV packet indicates the start of which basic divided slot in which divided frame and via which transmission path it is.

3. The transmitting device described in claim 1 or 2, characterized in that the divided frame generation means has a means for incrementing the numerical value of the packet type field in the first TLV packet indicating the first TLV packet of each basic divided slot from a predetermined initial value, and forming the identification information by repeating the increment within a predetermined range, and assigning it to each basic divided slot.

4. The broadcast transmission path of the first frequency band is a 12 GHz band satellite transmission path, and the broadcast transmission path of the second frequency band is a 21 GHz band satellite transmission path, 4. The transmitting device according to claim 1, wherein the divided frame generating means, when constructing the divided frames, calculates corresponding information bit rates based on the coding and modulation scheme of each of the multiple broadcast transmission paths, inserts nulls after the data assigned according to each information bit rate so that the frame length of the divided frames constituting each basic divided slot is a constant value, forms basic divided slots for the multiple broadcast transmission paths, assigns data for the broadcast transmission path of the first frequency band to the first basic divided slot, assigns data for the broadcast transmission path of the second frequency band from the second basic divided slot onwards, and assigns remaining data exceeding a maximum rate that can be transmitted on the broadcast transmission paths of the first frequency band and the second frequency band to a predetermined number of basic divided slots for transmission via the communication transmission paths of the IP network.

5. The transmitting device according to any one of claims 1 to 4, characterized in that the divided frame generating means, when dividing the specified data in TLV packet format and transmitting it in bulk, is capable of changing the number of slot divisions of the basic divided slots that constitute the divided frame, and has a means for notifying the receiving side of information on the number of slot divisions of the basic divided slots that constitute the divided frame and the unique number of each basic divided slot.

6. The transmitting device according to any one of claims 1 to 5, further comprising an IP encapsulation means for, when the divided frame constructed by the divided frame generation means includes a predetermined number of basic divided slots for transmission via a communication transmission path of an IP network, dividing the predetermined number of basic divided slots into IP-based packets consistent with the IP network, and assigning an IP sequence number to each divided IP-based packet to uniquely indicate the signal order of the packets, and transmitting the divided IP-based packets to a receiving device.

7. A receiving device that receives the predetermined data bulk-transmitted by the transmitting device according to any one of claims 1 to 6, a segment frame reconstruction means for receiving signals in a TLV packet format transmitted in bulk via the plurality of broadcast transmission paths and the communication transmission paths and reconstructing corresponding basic segment slots, and for IP-based packets transmitted via the communication transmission paths of an IP network, performing IP decapsulation, arranging the signal order based on an IP sequence number for uniquely indicating the signal order given in the packet, extracting the TLV signals and reconstructing the predetermined number of basic segment slots, and rearranging the segments to reconstruct the segment frames generated by the transmitting device based on the identification information; an output signal generating means for connecting the valid data of each basic divided slot based on the reconstructed divided frame, restoring predetermined data of the same signal format as that sent from the signal source device, and outputting the restored data to the outside; The receiving device is characterized in that, when receiving the signal in TLV packet format via both the broadcast transmission path of the first frequency band and the broadcast transmission path of the second frequency band, the divided frame reconstructing means adjusts the number of TLV packets that can be accommodated in each basic division slot, the number of divisions of the basic division slots and the NULL length in accordance with the coding rate of the LDPC code based on the number of basic division slots calculated by the ratio of the information bit rate that can be transmitted on the broadcast transmission path of the second frequency band to the maximum bit rate of the broadcast transmission path of the first frequency band, and reconstructs a divided frame consisting of the predetermined number of basic division slots.

8. The receiving device described in claim 7, characterized in that the divided frame reconstruction means determines the first TLV packet based on setting information in the TLV header of the TLV packet format signal received via the multiple broadcast transmission paths and the communication transmission path, identifies which TLV packet indicates the beginning of which basic divided slot in which divided frame, determines the TLV header between basic divided frames, and rearranges the divided frames generated by the transmitting device to reconstruct the divided frames.

9. The identification information is formed by incrementing the value of the packet type field in the head TLV packet indicating the head TLV packet of each basic division slot from a predetermined initial value, and repeating the increment within a predetermined range, and is assigned to each basic division slot; The receiving device described in claim 7 or 8, characterized in that the divided frame reconstruction means rearranges the divided frames to reconstruct them based on the numerical value of the packet type field in the first TLV packet that is assigned as the identification information among the TLV packet format signals received via the multiple broadcast transmission paths and the communication transmission path.

10. The receiving device described in any one of claims 7 to 9, characterized in that, when reconstructing the divided frames, the divided frame reconstruction means calculates the corresponding information bit rates based on the coding and modulation method of each of the multiple broadcast transmission paths, and inserts nulls after the data assigned according to each information bit rate so that the frame length of the divided frames constituting each basic divided slot is a constant value, thereby forming basic divided slots for the multiple broadcast transmission paths, and basic divided slots for the communication transmission path in accordance with the multiple broadcast transmission paths.

11. The receiving device described in any one of claims 7 to 10, characterized in that the divided frame reconstruction means has a means for identifying the structure of the divided frame to be reconstructed based on information on the number of slot divisions of the basic divided slots that constitute the divided frame and the unique number of each basic divided slot, which information is notified in advance from the transmitting device.

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