Transmitting device and transmission method

Abstract

To make it possible to improve transmission efficiency.SOLUTION: A transmission device is provided including a first time interleaver that performs first time interleaving conforming to a first system, on an error correction code block to be included as a data frame in a physical layer frame. The error correction code block conforms to a second system. When performing the first time interleaving, the first time interleaver applies a pointer indicating an offset of a start position of the error correction code block included at a start of the data frame. The present technique can be applied to, for example, a transmission system compatible with a broadcasting system such as ISDB-T system.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present technology relates to a transmission device and a transmission method, and particularly to a transmission device and a transmission method capable of improving transmission efficiency.

Background Art

[0002] For example, in Japan, studies have been conducted on the advancement towards the next generation of terrestrial digital television broadcasting, and various technical systems have been studied (see, for example, Patent Documents 1 to 3).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when starting the operation of the next-generation broadcasting system, a transition period from the current broadcasting system to the next-generation broadcasting system is provided, and even during that transition period, it is required to improve transmission efficiency.

[0005] The present technology has been made in view of such a situation and is intended to improve transmission efficiency.

Means for Solving the Problems

[0006] A transmitting device according to one aspect of this technology includes: a first multiplexing unit that multiplexes a signal of a first error correction code block conforming to a first method and a signal of a second error correction code block conforming to a second method, according to a hierarchical division multiplexing scheme; a first time interleaver that performs a first time interleave according to the first method on the first error correction code block and the second error correction code block included in the multiplexed signal; a second multiplexing unit that multiplexes a first transmission control signal conforming to the first method and a second transmission control signal conforming to the second method, according to the hierarchical division multiplexing scheme; and The transmitting device comprises a transmitting unit that transmits a broadcast signal by configuring a first physical layer frame containing a first transmission control signal with the first error correction code block after a first time interleaving as a first data frame, and a second physical layer frame containing a second transmission control signal with the second error correction code block after a first time interleaving as a second data frame, wherein the second transmission control signal includes a pointer indicating the offset of the starting position of the second error correction code block before the first time interleaving, which is included at the beginning of the second data frame.

[0007] The transmitting device, one aspect of this technology, may be an independent device or an internal block constituting a single device. Furthermore, the transmitting method, another aspect of this technology, is a transmitting method corresponding to the transmitting device described above.

[0008] In a transmitting device and transmission method representing one aspect of this technology, a signal of a first error correction code block conforming to a first method and a signal of a second error correction code block conforming to a second method are multiplexed according to a hierarchical division multiplexing scheme. A first time interleaving according to the first method is performed on the first and second error correction code blocks included in the multiplexed signal. A first transmission control signal conforming to a first method and a second transmission control signal conforming to a second method are multiplexed according to a hierarchical division multiplexing scheme. A first physical layer frame is formed with the first error correction code block after the first time interleaving as the first data frame and containing the first transmission control signal, and a second physical layer frame is formed with the second error correction code block after the first time interleaving as the second data frame and containing the second transmission control signal. These are transmitted as a broadcast signal, and the second transmission control signal includes a pointer indicating the offset of the starting position of the second error correction code block before the first time interleaving, which is included at the beginning of the second data frame.

[0009] A receiving device in one aspect of this technology includes: a first multiplexing unit that multiplexes a signal of a first error correction code block conforming to the first method and a signal of a second error correction code block conforming to the second method, according to a hierarchical division multiplexing scheme; a first time interleaver that performs a first time interleave according to the first method on the first error correction code block and the second error correction code block included in the multiplexed signal; a second multiplexing unit that multiplexes a first transmission control signal conforming to the first method and a second transmission control signal conforming to the second method, according to the hierarchical division multiplexing scheme; a first physical layer frame containing the first transmission control signal as a first data frame with the first error correction code block after the first time interleave; and a second transmission control signal as a second data frame with the second error correction code block after the first time interleave. The receiving device includes a transmitting unit that receives a broadcast signal transmitted from a transmitting device which comprises a transmitting unit that constitutes a second physical layer frame including the signal and transmits it as a broadcast signal; a receiving unit that receives a broadcast signal transmitted from a transmitting device which comprises a first error correction code block after the first time interleaving included in the first physical layer frame and a first time deinterleaver that performs a first time deinterleaving in accordance with the first method on the second error correction code block after the first time interleaving included in the second physical layer frame; and a pointer included in the second transmission control signal that indicates the offset of the starting position of the second error correction code block after the first time deinterleaving included at the beginning of the second data frame, and uses the acquired pointer to extract the second error correction code block after the first time deinterleaving from the second physical layer frame.

[0010] The receiving device, one aspect of this technology, may be an independent device or an internal block constituting a single device. Furthermore, the receiving method, another aspect of this technology, is a receiving method corresponding to the receiving device described above.

[0011] In one aspect of this technology, a receiving device and receiving method, a first time deinterleaving conforming to the first method is performed on the first error correction code block after the first time interleaving included in the first physical layer frame and the second error correction code block after the first time interleaving included in the second physical layer frame. A pointer indicating the offset of the starting position of the second error correction code block after the first time deinterleaving, which is included in the second transmission control signal, is obtained, and the second error correction code block after the first time deinterleaving is extracted from the second physical layer frame using the obtained pointer. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows an example of the configuration of one embodiment of a transmission system to which this technology is applied. [Figure 2] This diagram schematically represents the transmission of broadcast signals using a hierarchical division multiplexing scheme. [Figure 3] This figure shows examples of the signal spaces for UL signals and LL signals. [Figure 4] This figure shows the current system, the next-generation system, and examples of transmission specifications during the transition period between them. [Figure 5] This figure shows an example of applying a time-deinterleaved FEC block pointer. [Figure 6] This is a block diagram showing an example of the configuration of a transmitting device. [Figure 7] This is a flowchart explaining the transmission process. [Figure 8] This is a block diagram showing a first example of the configuration of a receiving device. [Figure 9] This is a flowchart illustrating the flow of the first receiving process. [Figure 10] This is a block diagram showing a second example of the configuration of a receiving device. [Figure 11] This is a flowchart explaining the flow of the second receiving process. [Figure 12] This is a block diagram showing a third example of the configuration of a receiving device. [Figure 13] It is a flowchart for explaining the flow of the third reception process. [Figure 14] It is a diagram showing a configuration example of a computer.

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present technology will be described with reference to the drawings. The description will be made in the following order.

[0014] 1. Embodiments of the Present Technology 2. Variations 3. Configuration of the Computer

[0015] <1. Embodiments of the Present Technology>

[0016] (Configuration Example of Transmission System) FIG. 1 is a diagram showing the configuration of an embodiment of a transmission system to which the present technology is applied. Note that a system refers to a logical aggregation of a plurality of devices.

[0017] In FIG. 1, the transmission system 1 is a system corresponding to a broadcasting method such as terrestrial digital television broadcasting. The transmission system 1 includes data processing devices 11-1 to 11-N (N is an integer of 1 or more) installed in facilities related to each broadcasting station, a transmission device 10 installed in a transmission station, and reception devices 20-1 to 20-M (M is an integer of 1 or more) owned by each user.

[0018] Also, in this transmission system 1, the data processing devices 11-1 to 11-N and the transmission device 10 are connected via communication lines 12-1 to 12-N. Note that the communication lines 12-1 to 12-N can be, for example, dedicated lines.

[0019] The data processing device 11-1 performs necessary processing such as encoding on the data of broadcast content (for example, a broadcast program, etc.) produced by the broadcasting station A, and transmits the resulting transmission data to the transmission device 10 via the communication line 12-1.

[0020] In data processing devices 11-2 to 11-N, similar to data processing device 11-1, data of broadcast content produced by each broadcasting station such as broadcasting station B and broadcasting station Z is processed, and the resulting transmission data is transmitted to the transmission device 10 via communication lines 12-2 to 12-N.

[0021] The transmitting device 10 receives transmission data from the data processing devices 11-1 to 11-N on the broadcasting station side via communication lines 12-1 to 12-N. The transmitting device 10 performs necessary processing such as encoding and modulation on the transmission data from the data processing devices 11-1 to 11-N, and transmits the resulting broadcast signal from a transmitting antenna installed at the transmitting station.

[0022] As a result, the broadcast signal from the transmitting device 10 at the transmission station is transmitted to the receiving devices 20-1 to 20-M, respectively, by radio waves in a predetermined frequency band.

[0023] The receiving devices 20-1 to 20-M are configured as fixed receivers such as television sets or set-top boxes (STBs), and are installed in each user's home or other location.

[0024] The receiving device 20-1 receives the broadcast signal transmitted from the transmitting device 10 using radio waves in a predetermined frequency band, and performs necessary processing such as demodulation, decoding, and reproducing broadcast content (e.g., broadcast programs) corresponding to the user's channel selection operation.

[0025] In receiving devices 20-2 to 20-M, the broadcast signal from the transmitting device 10 is processed in the same manner as in receiving device 20-1, and broadcast content corresponding to the user's channel selection operation is played back.

[0026] In this way, the receiving device 20 displays the video of the broadcast content on its screen and outputs audio synchronized with the video from its speaker, allowing the user to view broadcast content such as broadcast programs.

[0027] In transmission system 1, the M receiving devices 20 include both those compatible with the current system and those compatible with the next-generation system. Therefore, in the following explanation, the receiving devices 20 compatible with the current system will be referred to as current receiving devices 20L, and the receiving devices 20 compatible with the next-generation system will be referred to as next-generation receiving devices 20N to distinguish them.

[0028] Furthermore, a receiving device 20 that supports both the current and next-generation systems is also envisioned; therefore, in the following description, such a receiving device 20 will be referred to as the dual-type receiving device 20D. However, when there is no need to distinguish between the current receiving device 20L, the next-generation receiving device 20N, and the dual-type receiving device 20D, it will simply be referred to as the receiving device 20.

[0029] Incidentally, in Japan, discussions are underway to upgrade terrestrial digital television broadcasting to the next generation. One method being considered for transitioning from the current broadcasting system to the next-generation broadcasting system is to introduce a compatible next-generation system using the current frequency band.

[0030] During this transition period for broadcasting systems, it is envisioned that both the current broadcasting signal (hereinafter also referred to as the current broadcasting signal) and the next-generation broadcasting signal (hereinafter also referred to as the next-generation broadcasting signal) will be transmitted using the Layered Division Multiplexing (LDM) method.

[0031] In other words, during the transition period of broadcasting systems, the LDM (Layered Multiplexing) system is used to transmit current broadcasting signals in the high-power layer (UL: Upper Layer) and next-generation broadcasting signals in the low-power layer (LL: Lower Layer).

[0032] Here, Figure 2 schematically illustrates the transmission of broadcast signals using hierarchical division multiplexing. In Figure 2, the vertical axis represents the signal level, and the horizontal axis represents the frequency.

[0033] Figure 2 shows the frequency band of a single channel. As indicated by the vertical dashed lines, each frequency band consists of multiple segments (for example, 13 segments in the current system (ISDB-T system)). Here, by using a hierarchical division multiplexing method, the power of the next-generation broadcast signal is suppressed and multiplexed onto the current broadcast signal, making it possible to transmit the next-generation broadcast signal superimposed on the same frequency band as the current broadcast signal.

[0034] In Figure 2, current 2K broadcasts (the current broadcast signals) transmitted in the high-power tier (UL) transmit 2K content compatible with 2K video, while next-generation 4K broadcasts (the next-generation broadcast signals) transmitted in the low-power tier (LL) transmit 4K content compatible with 4K video. This demonstrates that broadcast signals for both 2K and 4K content can be transmitted on the same channel (frequency band). For example, current 2K broadcasts are received by the current receiving device 20L, while next-generation 4K broadcasts are received by the next-generation receiving device 20N or the dual-type receiving device 20D.

[0035] In this configuration, the receiving device 20, which supports hierarchical division multiplexing, first decodes the high-power UL signal from the broadcast signal transmitted from the transmitting device 10 to estimate the transmission point of the UL signal. Then, using the estimated transmission point of the UL signal, demapping and decoding of the low-power LL signal are performed.

[0036] For example, as shown in the example signal space in Figure 3, the transmission point of the UL signal, indicated by the black square in the figure, is estimated from the current broadcast signal modulated with QPSK (Quadrature Phase Shift Keying). Using this UL signal transmission point, demapping and decoding of the LL signal, indicated by the white circle in the figure, are performed. Specifically, in the example in Figure 3, the signal points of the eight LL signals (white circles in the figure) are arranged in a circle, centered around each of the four UL signal points (black squares in the figure).

[0037] Thus, since the LL signal is obtained based on the UL signal, if the time interleaving (time deinterleaving) patterns of the UL signal and the LL signal are different, the receiving device 20 will need to time interleave and then time deinterleave the decoded result of the UL signal in order to decode the LL signal. Therefore, if the time interleaving (time deinterleaving) patterns of the UL signal and the LL signal are different, the configuration and processing of the receiving device 20 will become complicated.

[0038] In other words, considering the feasibility of the receiving device 20, if the time interleaving (time deinterleaving) patterns are different, a dedicated memory (large-scale memory) used only during the transition period from the current system to the next-generation system will be required, and the processing will become complex. Therefore, it is essential to unify the time interleaving (time deinterleaving) patterns between the UL signal and the LL signal.

[0039] Therefore, this technology ensures that time interleaving (time deinterleaving) corresponding to the current system is used during the transition period from the current system to the next-generation system.

[0040] Furthermore, in the next-generation system, if the starting position of an error correction code block included in a physical layer frame (data frame) does not coincide with the starting position of the physical layer frame (data frame), a pointer indicating the offset of the starting position of the error correction code block is used. By using this pointer, efficient data transmission can be performed even when their starting positions do not coincide.

[0041] Specifically, for example, an OFDM (Orthogonal Frequency Division Multiplexing) frame can be used as the physical layer frame, an FEC (Forward Error Correction) block as the error correction block, and an FEC block pointer as the pointer. The following explanation will use these as examples.

[0042] On the other hand, the current system does not have the functionality of such a pointer. If time interleaving (time deinterleaving) compatible with the current system is used during the transition period, the time interleaving (time deinterleaving) patterns between UL signals and LL signals will be standardized, but the transmission efficiency of LL signals compatible with next-generation broadcast signals will decrease.

[0043] Therefore, this technology improves transmission efficiency by using time interleaving (time deinterleaving) compatible with the current system during the transition period, and by ensuring that pointers compatible with the next-generation system are applied to said time interleaving (time deinterleaving).

[0044] After the transition period, pointers compatible with the next-generation method will continue to be used, so you only need to switch the time interleaving (time deinterleaving) method from the one compatible with the current method to the one compatible with the next-generation method.

[0045] To summarize, the relationship between the current system (before the transition), the transition period, and the next-generation system (after the transition) in terms of the transmission specifications is as shown in Figure 4.

[0046] In other words, before the transition, the current system such as ISDB-T (Integrated Services Digital Broadcasting - Terrestrial) will be used, and a time interleaver (time deinterleaver) and error correction code (FEC) corresponding to the current system will be used, and the FEC block pointer will not be used. That is, the starting position of the FEC block corresponding to the current system coincides with the starting position of the OFDM frame (data frame), so the FEC block pointer is not necessary.

[0047] During the transition period, the current broadcast signals of the current system and the next-generation broadcast signals of the next-generation system will be transmitted using a hierarchical division multiplexing (LDM) system. As mentioned earlier, a time interleaver (time deinterleaver) compatible with the current system will be used in order to standardize the time interleaving (time deinterleaving) patterns between the UL signal and the LL signal.

[0048] Furthermore, during the transition period, a hierarchical division multiplexing scheme is used to transmit UL signals corresponding to the current broadcast signal and LL signals corresponding to the next-generation broadcast signal. In this case, the error correction code (FEC) corresponding to the current system does not require the use of an FEC block pointer. On the other hand, as mentioned earlier, during the transition period, the error correction code (FEC) corresponding to the next-generation system is configured so that the FEC block pointer is applied to time interleaving (time deinterleaving) corresponding to the current system.

[0049] After the transition, the next-generation method will be used, and therefore a time interleaver (time deinterleaver) and error correction code (FEC) compatible with the next-generation method will be used, as well as an FEC block pointer. In other words, in FEC blocks compatible with the next-generation method, the starting position of the FEC block may not coincide with the starting position of the OFDM frame (data frame), so an FEC block pointer that indicates the offset of the starting position of the FEC block is used.

[0050] The following describes in detail, with reference to Figures 5 to 13, the technology which uses time interleaving (time deinterleaving) compatible with the current method during the transition period, and applies a pointer (FEC block pointer) compatible with the next-generation method to said time interleaving (time deinterleaving).

[0051] For the sake of simplicity, this disclosure will only describe the current 2K broadcasting under the current ISDB-T system. However, in reality, under the current ISDB-T system, 12 of the 13 segments are used for broadcasting to fixed receivers (current 2K broadcasting), and the remaining 1 segment is used for broadcasting to mobile receivers (so-called One-Seg broadcasting).

[0052] (Example of time deinterleaving) Figure 5 shows an example of applying a FEC block pointer compatible with the next-generation system to a time deinterleave compatible with the current system in either the next-generation receiver 20N or the dual-type receiver 20D. In Figure 5, the direction of time is assumed to be from left to right.

[0053] In this case, the dual-type receiver 20D and the like process the received OFDM frames sequentially, and the size of these OFDM frames corresponds to the frame size of the current system, such as ISDB-T. In other words, the dual-type receiver 20D and the like perform time deinterleaving during the transition period to correspond to the current system, so the size of its OFDM frames corresponds to the current system.

[0054] Furthermore, OFDM frames contain transmission control signals along with data frames. Data frames contain multiple FEC blocks. While FEC blocks are considered to have a fixed length, FEC blocks compatible with the next-generation system have a longer fixed length than FEC blocks compatible with the current system.

[0055] In Figure 5, in the dual-type receiver 20D, for each OFDM frame, multiple FEC blocks with time interleaving corresponding to the current system are extracted, and time deinterleaving corresponding to the current system is performed. The FEC blocks subject to this time deinterleaving are designated as FEC blocks corresponding to the next-generation system.

[0056] Figure 5A shows the FEC blocks before time deinterleaving. In Figure 5A, multiple FEC blocks are interleaved in the time direction according to a predetermined pattern corresponding to the current system, and their temporal order is rearranged. Here, each of the patterned squares in the figure represents a part of an FEC block, and by rearranging them in their original temporal order and gathering squares with the same pattern, one FEC block is formed.

[0057] Figure 5B shows the FEC block after time deinterleaving. In Figure 5B, time deinterleaving is performed so that each of the multiple FEC blocks whose temporal order has been rearranged for each OFDM frame is returned to its original temporal order.

[0058] In this case, the starting position of the OFDM frame (data frame) and the starting position of the FEC block do not coincide. However, in dual-type receivers such as the 20D, the starting position of the FEC block can be recognized by using an FEC block pointer. For example, this FEC block pointer specifies the number of data carriers from the beginning of the OFDM frame as the offset of the starting position of the FEC block.

[0059] Specifically, in the first OFDM frame, the number of data carriers from the beginning of that OFDM frame is specified as FEC block pointer P1, and in the second OFDM frame, the number of data carriers from the beginning of that OFDM frame is specified as FEC block pointer P2.

[0060] In Figure 5, the time deinterleaving performed by the next-generation receiver 20N or the dual-type receiver 20D on the receiving side is explained. However, the transmitting device 10 on the transmitting side performs time interleaving that corresponds to the time deinterleaving. That is, the transmitting device 10 interleaves in the time direction by rearranging the temporal order of the multiple FEC blocks shown in Figure 5B in a predetermined pattern corresponding to the current system (Figure 5A).

[0061] In this way, during the transition period, transmission efficiency can be improved by using time interleaving (time deinterleaving) that corresponds to the current system, and by ensuring that the FEC block pointer used in the FEC block that corresponds to the next-generation system is applied to said time interleaving (time deinterleaving).

[0062] In other words, by applying an FEC block pointer, the receiving device 20 can extract the FEC block from the OFDM frame even if the starting position of the FEC block included at the beginning of the OFDM frame does not coincide with the starting position of the OFDM frame. In other words, this technology can be understood as follows: If a single FEC block cannot be placed across multiple OFDM frames (data frames), it is necessary to perform, for example, zero-padding or place a NULL value in the area at the end of the OFDM frame where the FEC block cannot be placed. In contrast, with this technology, a single FEC block is allowed to be placed across multiple OFDM frames (data frames), so there is no need to perform, for example, zero-padding or place a NULL value, and a part of the FEC block can be placed in the end of the OFDM frame, and as a result, the decrease in transmission efficiency is suppressed.

[0063] (Configuration of the transmitting device) Figure 6 is a block diagram showing an example of the configuration of the transmitter 10 in Figure 1.

[0064] In Figure 6, the transmitting device 10 consists of FEC unit 111-1, FEC unit 111-2, power control unit 112, adder unit 113, power normalization unit 114, signal processing unit 115-1, signal processing unit 115-2, selector 116, OFDM modulation unit 117, selector 118, FEC pointer calculation unit 119, TMCC generation unit 120-1, TMCC generation unit 120-2, power control unit 121, adder unit 122, power normalization unit 123, and selector 124.

[0065] In Figure 6, a sequence of data signals is formed by the FEC units 111 to selector 116, a sequence of transmission control signals is formed by selector 118 to selector 124, and the signals obtained from these sequences are input to the OFDM modulation unit 117, respectively.

[0066] First, let's explain the sequence of data signals shown in the upper section.

[0067] The FEC unit 111-1 is an FEC encoding and modulation unit that conforms to the specifications of the current system. The FEC unit 111-1 applies forward error correction (FEC) to the 2K content signal (2K signal) input thereto as transmission data, and supplies the resulting 2K FEC signal to the summing unit 113.

[0068] The FEC unit 111-2 is an FEC encoding and modulation unit that conforms to the specifications of the next-generation system. The FEC unit 111-2 applies forward error correction (FEC) to the 4K content signal (4K signal) input thereto as transmission data, and supplies the resulting 4K FEC signal to the power control unit 112 and the signal processing unit 115-2.

[0069] The power control unit 112 performs power control on the 4K FEC signal supplied from the FEC unit 111-2, and supplies the resulting signal (4K FEC signal) to the adder unit 113.

[0070] The adder 113 adds the 2K FEC signal supplied from the FEC unit 111-1 and the 4K FEC signal supplied from the power control unit 112, and supplies the resulting added signal to the power normalization unit 114. The power normalization unit 114 normalizes the power of the added signal supplied from the adder 113 and supplies it to the signal processing unit 115-1.

[0071] In other words, the signals input to the signal processing unit 115-1 are transmitted using a hierarchical division multiplexing method during the transition period. Therefore, the power control unit 112, the summing unit 113, and the power normalization unit 114 perform processing to transmit the 2K content signal (2K FEC signal) in the high-power tier (UL) and the 4K content signal (4K FEC signal) in the low-power tier (LL).

[0072] The signal processing unit 115-1 is a signal processing unit that conforms to the specifications of the current system. The signal processing unit 115-1 consists of a hierarchical combining unit 141-1, a time interleaver 142-1, and a frequency interleaver 143-1.

[0073] The hierarchical synthesis unit 141-1 performs hierarchical synthesis processing corresponding to the segment on the signal input thereto, and supplies the resulting signal to the time interleaver 142-1.

[0074] The time interleaver 142-1 performs time interleaving (interleaving in the time direction) on the signal supplied from the hierarchical synthesis unit 141-1, and supplies the signal after time interleaving to the frequency interleaver 143-1. Here, the time interleaving performed by the time interleaver 142-1 is the same time interleaving as the time deinterleaving shown in Figure 5.

[0075] The frequency interleaver 143-1 performs frequency interleaving (interleaving in the frequency direction) on the signal supplied from the time interleaver 142-1, and supplies the signal after frequency interleaving to the selector 116.

[0076] On the other hand, the signal input to the signal processing unit 115-2 is the signal of 4K content (4K FEC signal) to be transmitted using the next-generation method after the transition. The signal processing unit 115-2 is a signal processing unit that complies with the specifications of the next-generation method. The signal processing unit 115-2 consists of a hierarchical synthesis unit 141-2, a time interleaver 142-2, and a frequency interleaver 143-2.

[0077] The hierarchical synthesis unit 141-2 performs processing related to hierarchical synthesis. The time interleaver 142-2 performs time interleaving on the signal input thereto. The frequency interleaver 143-2 performs frequency interleaving on the signal input thereto. The signal after this frequency interleaving is supplied to the selector 116.

[0078] The selector 116 switches its input to either the signal processing unit 115-1 or the signal processing unit 115-2 according to the switching signal supplied thereto. If the switching signal is a signal corresponding to the transition period, the selector 116 selects the LDM-compatible data signal processed by the signal processing unit 115-1, and if the switching signal is a signal corresponding to the post-transition period, it selects the next-generation data signal processed by the signal processing unit 115-2, and outputs them to the OFDM modulation unit 117, respectively.

[0079] Furthermore, the switching signal will be a signal corresponding to the transition period if the operation at that time is being carried out in accordance with the transition period from the current system to the next-generation system, and a signal corresponding to the post-transition operation if the operation is being carried out after the transition to the next-generation system. For example, the switching signal may be notified from a control circuit (not shown) or from an external source. The same applies to the switching signals supplied to other selectors by the transmitting device 10.

[0080] Next, we will explain the sequence of transmission control signals shown in the lower section.

[0081] The selector 118 selects the frame size of the current system, such as the ISDB-T system, if the switching signal supplied to it is a signal corresponding to the transition period, and selects the frame size of the next-generation system if the switching signal is a signal corresponding to the post-transition period, and supplies these to the FEC pointer calculation unit 119.

[0082] The FEC pointer calculation unit 119 calculates an FEC block pointer based on the frame size supplied from the selector 118 and supplies it to the TMCC generation unit 120-2.

[0083] Here, for example, based on the frame size of the OFDM frame corresponding to the current or next-generation method, the number of data carriers from the beginning of the OFDM frame is determined as an FEC block pointer, which indicates the offset of the starting position of the FEC block included at the beginning of the OFDM frame (data frame).

[0084] The TMCC generation unit 120-1 generates a TMCC (Transmission Multiplexing Configuration Control) signal (hereinafter also referred to as the current TMCC signal) as a transmission control signal corresponding to the specifications of the current system, and supplies it to the summing unit 122. The TMCC signal is a control signal that includes information such as the modulation scheme and error correction coding rate of each layer, as well as other transmission parameters.

[0085] The TMCC generation unit 120-2 generates a TMCC signal (hereinafter also referred to as the next-generation TMCC signal) as a transmission control signal corresponding to the specifications of the next-generation system, and supplies it to the power control unit 121 and the selector 124. This next-generation TMCC signal includes an FEC block pointer supplied from the FEC pointer calculation unit 119.

[0086] The power control unit 121 performs power control on the signal (next-generation TMCC signal) supplied from the TMCC generation unit 120-2, and supplies the resulting signal to the adder unit 122.

[0087] The adder 122 adds the signal supplied from the TMCC generation unit 120-1 (current TMCC signal) and the signal supplied from the power control unit 121 (next-generation TMCC signal), and supplies the resulting added signal to the power normalization unit 123. The power normalization unit 123 normalizes the power of the added signal supplied from the adder 122 and supplies it to the selector 124.

[0088] In other words, the signal input to this selector 124 (LDM-compatible transmission control signal) is transmitted using a hierarchical division multiplexing method during the transition period. Therefore, the power control unit 121, the adder 122, and the power normalization unit 123 perform processing to transmit the transmission control signal corresponding to the current system (current TMCC signal) in the high-power tier (UL) and the transmission control signal corresponding to the next-generation system (next-generation TMCC signal) in the low-power tier (LL).

[0089] Furthermore, the other signal input to selector 124, that is, the signal supplied from TMCC generation unit 120-2 (next-generation transmission control signal), is a transmission control signal (next-generation TMCC signal) that corresponds to the next-generation system and will be transmitted using the next-generation system after the transition.

[0090] The selector 124 selects the LDM-compatible transmission control signal from the power normalization unit 123 if the switching signal supplied to it is a signal corresponding to the transition period, and selects the next-generation transmission control signal from the TMCC generation unit 120-2 if the switching signal is a signal corresponding to the post-transition period, and outputs the respective to the OFDM modulation unit 117.

[0091] In this case, when operation is performed according to the transition period, the OFDM modulation unit 117 is supplied with LDM-compatible data signals from the data signal sequence selector 116 and with LDM-compatible transmission control signals from the transmission control signal sequence selector 124.

[0092] In this case, the OFDM modulation unit 117 constructs (generates) an OFDM frame as a physical layer frame based on the LDM-compatible data signal and the LDM-compatible transmission control signal. The OFDM modulation unit 117 also performs processing on the OFDM frame configuration, such as inserting IFFT (Inverse Fast Fourier Transform) and GI (Guard Interval), and the resulting signal is transmitted as a broadcast signal from a transmitting antenna (not shown).

[0093] Thus, during the transition period, the transmitter 10 will use a hierarchical division multiplexing method, so that the current 2K broadcast (the current broadcast signal) will be transmitted in the high-power tier (UL), and the next-generation 4K broadcast (the next-generation broadcast signal) will be transmitted in the low-power tier (LL).

[0094] Furthermore, when operating according to the post-migration requirements, the OFDM modulation unit 117 is supplied with next-generation data signals from the data signal sequence selector 116 and next-generation transmission control signals from the transmission control signal sequence selector 124.

[0095] In this case, the OFDM modulation unit 117 constructs an OFDM frame as a physical layer frame based on the next-generation data signal and the next-generation transmission control signal. The OFDM modulation unit 117 also performs processing such as IFFT and GI insertion on the OFDM frame configuration, and the resulting signal is transmitted as a broadcast signal from a transmitting antenna (not shown).

[0096] Thus, after the transition, the transmission device 10 will only transmit the next-generation 4K broadcast (the next-generation broadcast signal) after the transition.

[0097] In Figure 6, an example is shown where the FEC block pointer is included in the TMCC signal; however, the FEC block pointer may be included in other signals as well. For example, the FEC block pointer may be included in the header of the data frame of an OFDM frame. However, including it in the header will reduce the amount of transmitted data compared to including it in the TMCC signal.

[0098] Furthermore, as will be explained in more detail later, the TMCC signal may include an operation determination signal to notify the receiving device 20 whether the operation at that time is in accordance with the transition period or in accordance with the post-transition period.

[0099] (Transmission process flow) Next, referring to the flowchart in Figure 7, we will explain the flow of the transmission process performed by the transmission device 10 in Figure 6.

[0100] In step S101, FEC units 111-1 and 111-2 perform FEC coding and modulation processing. Here, FEC unit 111-1 performs FEC coding and modulation processing on the 2K signal. FEC unit 111-2 also performs FEC coding and modulation processing on the 4K signal.

[0101] In the determination process in step S102, it is determined whether the operation at that time is during the transition period or after the transition.

[0102] If it is determined in step S102 that the transition period is in progress, the process proceeds to step S103, and the processes in steps S103 to S107, S111, and S112 are executed.

[0103] In other words, the power control unit 112, the adder 113, and the power normalization unit 114 perform FEC LDM modulation processing to transmit the 2K FEC signal in the high-power layer (UL) and the 4K FEC signal in the low-power layer (LL) (S103).

[0104] Then, the time interleaver 142-1 performs time interleaving on the signal obtained as a result of the FEC LDM modulation processing (S104). In addition, the frequency interleaver 143-1 performs frequency interleaving on the signal after time interleaving (S105).

[0105] Next, the TMCC generation unit 120-1 and the TMCC generation unit 120-2 perform TMCC coding and modulation processing (S106). Here, the TMCC generation unit 120-1 performs TMCC coding and modulation processing on the current TMCC signal. The TMCC generation unit 120-2 also performs TMCC coding and modulation processing on the next-generation TMCC signal.

[0106] Furthermore, the power control unit 121, the adder 122, and the power normalization unit 123 perform TMCC LDM modulation processing to transmit the current TMCC signal in the high-power layer (UL) and the next-generation TMCC signal in the low-power layer (LL) (S107). Here, TMCC coding modulation processing is further performed, and an operation determination signal indicating that the operation is in accordance with the transition period is included (S111).

[0107] The OFDM modulation unit 117 then performs OFDM modulation processing based on the LDM-compatible data signal and the LDM-compatible transmission control signal (S112). The signal obtained as a result of this OFDM modulation processing is transmitted as a broadcast signal via the transmission antenna.

[0108] On the other hand, if it is determined in step S102 that the transition has already occurred, the process proceeds to step S108, and the processes in steps S108 to S112 are executed.

[0109] Specifically, the time interleaver 142-2 performs time interleaving on the 4K FEC signal (S108). The frequency interleaver 143-2 then performs frequency interleaving on the signal after time interleaving (S109).

[0110] Next, the TMCC generation unit 120-2 performs TMCC coding modulation processing on the next-generation TMCC signal (S110). An operation determination signal indicating that the operation is appropriate for the post-transition period is included here (S111).

[0111] The OFDM modulation unit 117 then performs OFDM modulation processing based on the next-generation data signal and the next-generation transmission control signal (S112). The signal obtained as a result of this OFDM modulation processing is transmitted as a broadcast signal via the transmission antenna.

[0112] The above explains the flow of the transmission process.

[0113] (Configuration of the receiving device) Figure 8 is a block diagram showing a first example of the configuration of the receiving device 20 in Figure 1. Note that the receiving device 20 shown in Figure 8 is configured as, for example, a next-generation receiving device 20N or a dual-type receiving device 20D.

[0114] In Figure 8, the receiving device 20 consists of an OFDM demodulation unit 211, a TMCC demodulation / decoding unit 212, a TMCC LDM demodulation unit 213, a transition period determination unit 214, a selector 215, a TMCC demodulation / decoding unit 216, a frequency deinterleaver 217-1, a frequency deinterleaver 217-2, a selector 218, a RAM 219, a time deinterleaver 220-1, a time deinterleaver 220-2, a selector 221, a RAM 222, a FEC demodulation / decoding unit 223, a FEC LDM demodulation unit 224, a selector 225, and a FEC demodulation / decoding unit 226.

[0115] In Figure 8, the TMCC demodulation / decoding units 212 to 216 form a sequence of transmission control signals, the frequency deinterleavers 217 to 226 form a sequence of data signals, and the OFDM demodulation unit 211 is input to these sequences, respectively.

[0116] The OFDM demodulator 211 receives the broadcast signal received via a receiving antenna (not shown). The OFDM demodulator 211 processes the input broadcast signal, performing operations such as removing the GI, performing an FFT (Fast Fourier Transform), and demodulating OFDM frames. The resulting signal is then output to the subsequent block.

[0117] Here, from the signals output from the OFDM demodulation unit 211, the LDM-compatible transmission control signal is supplied to the TMCC demodulation / decoding unit 212 and the TMCC LDM demodulation unit 213, and the LDM-compatible data signal is supplied to the frequency deinterleaver 217-1. In addition, from the signals output from the OFDM demodulation unit 211, the next-generation transmission control signal is supplied to the selector 215, and the next-generation data signal is supplied to the frequency deinterleaver 217-2.

[0118] The TMCC demodulation / decoding unit 212 demodulates the signal (LDM-compatible transmission control signal) supplied from the OFDM demodulation unit 211 according to a predetermined demodulation method for each carrier on which the TMCC signal is located, decodes the demodulation result, and supplies the resulting operation determination signal to the transition period determination unit 214.

[0119] This operational determination signal indicates whether the current operation is in accordance with the transition period or the post-transition period. This operational determination signal can be represented, for example, by a predetermined set of bits, and the same bit position can be assigned regardless of whether it is during or after the transition period.

[0120] The transition period determination unit 214 determines whether the operation at that time is a transition period or a post-transition operation based on the operation determination signal supplied from the TMCC demodulation / decoding unit 212, and supplies switching signals corresponding to the result of the determination to selectors 215, 218, 221, and 225, respectively.

[0121] Furthermore, the signal from the TMCC demodulation / decoding unit 212 is supplied to the TMCC LDM demodulation unit 213. The TMCC LDM demodulation unit 213 performs LDM demodulation based on the signals from the OFDM demodulation unit 211 and the TMCC demodulation / decoding unit 212, and supplies a signal corresponding to the demodulation result to the selector 215.

[0122] During the transition period, a hierarchical division multiplexing scheme is used, with the current TMCC signal being transmitted in the high-power tier (UL) and the next-generation TMCC signal being transmitted in the low-power tier (LL). This LDM demodulation enables the demodulation and decoding of the next-generation TMCC signal transmitted in the low-power tier (LL).

[0123] The selector 215 receives signals from the OFDM demodulation unit 211 (next-generation transmission control signal) and the TMCC LDM demodulation unit 213. If the switching signal from the transition period determination unit 214 corresponds to the transition period, the selector 215 selects the signal from the TMCC LDM demodulation unit 213. If the switching signal corresponds to the post-transition state, the selector 215 selects the signal from the OFDM demodulation unit 211 and outputs them to the TMCC demodulation / decoding unit 216.

[0124] The TMCC demodulation / decoding unit 216 is compatible with the next-generation system and demodulates the signal supplied from the selector 215 according to a predetermined demodulation system, decodes the demodulation result, and obtains a next-generation TMCC signal. The TMCC demodulation / decoding unit 216 supplies the FEC block pointer, one of the parameters included in the obtained next-generation TMCC signal, to the time deinterleaver 220-1 and time deinterleaver 220-2.

[0125] Frequency deinterleaver 217-1 is a frequency deinterleaver that conforms to the specifications of the current system. On the other hand, frequency deinterleaver 217-2 is a frequency deinterleaver that conforms to the specifications of the next-generation system. Selector 218 and RAM 219 are provided for frequency deinterleavers 217-1 and 217-2.

[0126] Selector 218 switches its input to frequency deinterleaver 217-1 if the switching signal corresponds to the transition period, and switches its input to frequency deinterleaver 217-2 if the switching signal corresponds to the post-transition period. This allows the frequency deinterleaver 217 corresponding to the current or next-generation system specifications to use RAM 219, depending on whether the operation at that time is during the transition period or post-transition.

[0127] Time deinterleaver 220-1 is a time deinterleaver that conforms to the specifications of the current system. On the other hand, time deinterleaver 220-2 is a time deinterleaver that conforms to the specifications of the next-generation system. Selectors 221 and RAM 222 are provided for time deinterleavers 220-1 and 220-2.

[0128] Selector 221 switches its input to time deinterleaver 220-1 if the switching signal corresponds to the transition period, and switches its input to time deinterleaver 220-2 if the switching signal corresponds to the post-transition period. This allows the time deinterleaver 220 corresponding to the current or next-generation system specifications to use RAM 222, depending on whether the operation at that time is during the transition period or post-transition.

[0129] In other words, during the transition period, the frequency deinterleaver 217-1 performs frequency deinterleaving (frequency-direction deinterleaving) by appropriately writing and reading signals (LDM-compatible data signals) supplied from the OFDM demodulation unit 211 to the RAM 219, and then supplies the signal after frequency deinterleaving to the time deinterleaver 220-1.

[0130] The time deinterleaver 220-1 is supplied with a signal from the frequency deinterleaver 217-1 along with an FEC block pointer from the TMCC demodulation / decoding unit 216. The time deinterleaver 220-1 performs time deinterleaving (deinterleaving in the time direction) by appropriately writing and reading the signal after frequency deinterleaving to and from the RAM 222, and supplies the signal after time deinterleaving to the FEC demodulation / decoding unit 223 and the FEC LDM demodulation unit 224.

[0131] Here, the time deinterleaving performed by the time deinterleaver 220-1 corresponds to the time deinterleaving shown in Figure 5. Furthermore, even if the starting position of the OFDM frame (data frame) and the starting position of the FEC block do not coincide, the starting position of the FEC block can be recognized by using the FEC block pointer, and multiple FEC blocks contained in the OFDM frame can be read out on an FEC block basis.

[0132] The FEC demodulation and decoding unit 223 is compatible with the current system and demodulates the signal supplied from the time deinterleaver 220-1 according to a predetermined demodulation method, decodes the demodulation result, and supplies the resulting signal to the FEC LDM demodulation unit 224.

[0133] The FEC LDM demodulation unit 224 performs LDM demodulation based on the signals supplied from the time deinterleaver 220-1 and the FEC demodulation / decoding unit 223, and supplies a signal corresponding to the demodulation result to the selector 225.

[0134] During the transition period, a hierarchical division multiplexing scheme is used, where 2K content signals (2K FEC signals) are transmitted in the high-power tier (UL), and 4K content signals (4K FEC signals) are transmitted in the low-power tier (LL). This LDM demodulation enables the demodulation and decoding of the 4K FEC signals transmitted in the low-power tier (LL).

[0135] On the other hand, after the transition, the frequency deinterleaver 217-2 performs frequency deinterleaving by appropriately writing and reading the signal (next-generation data signal) supplied from the OFDM demodulation unit 211 to the RAM 219, and then supplies the frequency-deinterleaved signal to the time deinterleaver 220-2.

[0136] The time deinterleaver 220-2 is supplied with a signal from the frequency deinterleaver 217-2 along with an FEC block pointer from the TMCC demodulation / decoding unit 216. The time deinterleaver 220-2 performs time deinterleaving by appropriately writing and reading the signal after frequency deinterleaving to and from the RAM 222, and supplies the signal after time deinterleaving to the selector 225.

[0137] Furthermore, if the starting position of the OFDM frame (data frame) and the starting position of the FEC block do not coincide, the starting position of the FEC block can be determined by using the FEC block pointer.

[0138] The selector 225 receives signals from the FEC LDM demodulation unit 224 and the time deinterleaver 220-2. If the switching signal from the transition period determination unit 214 corresponds to the transition period, the selector 225 selects the signal from the FEC LDM demodulation unit 224. If the switching signal corresponds to the post-transition state, the selector 225 selects the signal from the time deinterleaver 220-2 and supplies them to the FEC demodulation and decoding unit 226.

[0139] In other words, when operating according to the transition period, the 4K FEC signal obtained from the next-generation broadcast signal transmitted in the low-power tier (LL) of the hierarchical division multiplexing scheme is input to the FEC demodulation and decoding unit 226 as a signal from the FEC LDM demodulation unit 224. On the other hand, when operating according to the post-transition period, the 4K FEC signal obtained from the next-generation broadcast signal of the post-transition next-generation 4K broadcast is input to the FEC demodulation and decoding unit 226.

[0140] The FEC demodulation and decoding unit 226 is compatible with next-generation systems and demodulates the 4K FEC signal supplied from the selector 225 according to a predetermined demodulation method. It then decodes the demodulation result and outputs the resulting 4K signal to a subsequent circuit (e.g., a decoder).

[0141] As a result, for example, in the next-generation receiver 20N or the dual-type receiver 20D, during the transition period, 4K signals obtained from next-generation broadcast signals transmitted in the low-power tier (LL) of the hierarchical division multiplexing scheme are processed, and after the transition, 4K signals obtained from next-generation broadcast signals of the next-generation 4K broadcast after the transition are processed. Therefore, in the next-generation receiver 20N or the dual-type receiver 20D, 4K content from next-generation 4K broadcasts can be viewed both during and after the transition period.

[0142] (Flow of the first receiving process) Next, referring to the flowchart in Figure 9, the flow of the first reception process performed by the receiving device 20 (next-generation receiving device 20N or dual-type receiving device 20D) in Figure 8 will be explained.

[0143] In step S201, the OFDM demodulation unit 211 performs OFDM demodulation processing on the broadcast signal received via the receiving antenna.

[0144] In step S202, the TMCC demodulation / decoding unit 212 performs TMCC demodulation / decoding based on the results of the OFDM demodulation process. This TMCC demodulation / decoding process detects the operation determination signal.

[0145] In step S203, the transition period determination unit 214 determines, based on the detected operation determination signal, whether the operation at that time is during the transition period or after the transition.

[0146] If it is determined in step S203 that it is a transition period, the process proceeds to step S204, and the processes in steps S204 through S208 and S212 are executed.

[0147] In other words, the TMCC demodulation / decoding unit 212 performs TMCC demodulation / decoding processing corresponding to the current system, and the TMCC LDM demodulation unit 213 performs TMCC LDM demodulation processing (S204), thereby processing the LL signal in the low-power layer using the UL signal in the high-power layer. As a result, the TMCC demodulation / decoding unit 216 performs TMCC demodulation / decoding processing corresponding to the next-generation system (S205), thereby obtaining a next-generation TMCC signal including the FEC block pointer.

[0148] Then, the frequency deinterleaver 217-1 performs frequency deinterleaving on the signal obtained as a result of OFDM demodulation (S206). In addition, the time deinterleaver 220-1 performs time deinterleaving on the signal after frequency deinterleaving (S207).

[0149] Next, the FEC demodulation / decoding unit 223 performs FEC demodulation / decoding processing compatible with the current system, and the FEC LDM demodulation unit 224 performs FEC LDM demodulation processing (S208), thereby using the high-power UL signal to process the low-power LL signal. As a result, the FEC demodulation / decoding unit 226 performs FEC demodulation / decoding processing compatible with the next-generation system (S212), obtaining a 4K signal which is then output to the subsequent circuit.

[0150] On the other hand, if it is determined in step S203 that the transition has already occurred, the process proceeds to step S209, and the processes in steps S209 through S212 are executed.

[0151] In other words, the TMCC demodulation / decoding unit 216 performs TMCC demodulation / decoding processing corresponding to the next-generation system based on the results of the OFDM demodulation processing (S209). This TMCC demodulation / decoding processing yields a next-generation TMCC signal including the FEC block pointer.

[0152] Then, the frequency deinterleaver 217-2 performs frequency deinterleaving on the signal obtained as a result of OFDM demodulation (S210). In addition, the time deinterleaver 220-2 performs time deinterleaving on the signal after frequency deinterleaving (S211).

[0153] Subsequently, the FEC demodulation and decoding unit 226 performs FEC demodulation and decoding processing on the signal after time deinterleaving (S212) to obtain a 4K signal, which is then output to the subsequent circuit. Once the processing in step S212 is completed, the first reception process shown in Figure 9 is terminated.

[0154] The above explains the flow of the first receiving process.

[0155] (Configuration of the receiving device) Figure 10 is a block diagram showing a second example of the configuration of the receiving device 20 shown in Figure 1. Note that the receiving device 20 shown in Figure 10 is configured as, for example, a next-generation receiving device 20N or a dual-type receiving device 20D.

[0156] The second example of the configuration shown in Figure 10 differs from the first example of the configuration shown in Figure 8 in that the transition period determination unit 214 is removed, and the transition period and the switching signal after the transition are set externally. In this configuration, for example, if the next-generation receiver 20N or the dual-type receiver 20D is a television receiver, the switching signal can be set from outside the circuit (demodulation IC) that has a demodulation function, such as the firmware of the television set.

[0157] In the second example of the configuration shown in Figure 10, similar to the first example of the configuration shown in Figure 8, switching signals are supplied to selectors 215, 218, 221, and 225, respectively, and each selector selects and outputs an input signal according to the switching signal.

[0158] (The second reception processing flow) Next, referring to the flowchart in Figure 11, we will explain the flow of the second reception process performed by the receiving device 20 (next-generation receiving device 20N or dual-type receiving device 20D) in Figure 10.

[0159] The second reception process shown in Figure 11 differs from the first reception process shown in Figure 9 in that the determination process in step S233 is different from the determination process in step S203.

[0160] In the determination process in step S233, it is determined whether the setting to switch the operation has been made based on external settings such as the firmware of the TV set, that is, whether the operation at that time is during the transition period or after the transition.

[0161] If it is determined in step S233 that the transition period has begun, the process proceeds to step S234, and the processes in steps S234 through S238 and S242 are executed. On the other hand, if it is determined in step S233 that the transition has ended, the process proceeds to step S239, and the processes in steps S239 through S242 are executed.

[0162] Furthermore, the processes other than step S233, namely steps S231, S232, and S234 to S242 in Figure 11, are the same as the processes in steps S201, S202, and S204 to S212 in Figure 9.

[0163] The above explains the flow of the second receiving process.

[0164] (Configuration of the receiving device) Figure 12 is a block diagram showing a third example of the configuration of the receiving device 20 in Figure 1. Note that the receiving device 20 shown in Figure 10 is configured as a dual-type receiving device 20D.

[0165] The third example of the configuration shown in Figure 12 differs from the first example of the configuration shown in Figure 8 in that selectors 241 and 242 are added, allowing for the selection of signals according to the current system.

[0166] Here, for example, the transition period determination unit 214 determines whether the operation at that time is the current system (pre-transition) operation based on a signal (e.g., operation determination signal) supplied from the TMCC demodulation / decoding unit 212, and supplies switching signals to selectors 241 and 242 according to the result of that determination.

[0167] Selector 241 selects '0' and supplies it to time deinterleaver 220-1 if the switching signal from transition period determination unit 214 is a signal corresponding to the current system (before transition). In other words, the starting position of the FEC block corresponding to the current system coincides with the starting position of the OFDM frame (data frame), and since an FEC block pointer is not needed, '0' is input here.

[0168] Furthermore, if the switching signal from the transition period determination unit 214 is not a signal corresponding to the current system (before transition) (i.e., it is a signal corresponding to the transition period or after transition), the selector 241 selects a signal from the TMCC demodulation / decoding unit 216 (FEC block pointer) and supplies it to the time deinterleaver 220-1 or time deinterleaver 220-2.

[0169] If the switching signal from the transition period determination unit 214 is a signal corresponding to the current system (before the transition), the selector 242 selects the signal (2K signal) from the FEC demodulation / decoding unit 223 corresponding to the current system and outputs it to the subsequent circuit (e.g., a decoder). As a result, the dual-system receiving device 20D can view 2K content from the current 2K broadcast.

[0170] Furthermore, if the switching signal from the transition period determination unit 214 is not a signal corresponding to the current system (before transition) (i.e., it is a signal corresponding to the transition period or after transition), the selector 242 selects the signal (4K signal) from the FEC demodulation / decoding unit 226 that corresponds to the next-generation system and outputs it to the subsequent circuit. As a result, the dual-type receiver 20D will be able to view 4K content from next-generation 4K broadcasting.

[0171] (The third receiving process flow) Next, referring to the flowchart in Figure 13, we will explain the flow of the third reception process performed by the receiving device 20 (both-type receiving device 20D) in Figure 12.

[0172] The third reception process shown in Figure 13 differs from the first reception process shown in Figure 9 in that the determination process in step S263 is different from the determination process in step S203.

[0173] In the determination process in step S263, it is determined whether the operation at that time is during the transition period or after the transition, as well as whether it is the current system (before the transition).

[0174] If it is determined in step S263 that the current method (before migration) is being used, the process proceeds to step S264, and the processes in steps S264 through S266 are executed.

[0175] Specifically, the frequency deinterleaver 217-1 performs frequency deinterleaving on the signal obtained as a result of OFDM demodulation processing (the current data signal) (S264). In addition, the time deinterleaver 220-1 performs time deinterleaving on the signal after frequency deinterleaving (S265).

[0176] Then, the FEC demodulation and decoding unit 223 performs FEC demodulation and decoding processing in accordance with the current system (S266), thereby obtaining a 2K signal from the 2K FEC signal, which is output to the subsequent circuit.

[0177] If it is determined in step S263 that the transition period is in progress, the process proceeds to step S267, and the processes in steps S267 to S271 and S275 are executed. These processes are the same as those in steps S204 to S208 and S212 in Figure 9.

[0178] Furthermore, if it is determined in step S263 that the transition has occurred, the process proceeds to step S272, and the processes in steps S272 to S275 are executed. These processes are the same as those in steps S209 to S212 in Figure 9.

[0179] The above explains the flow of the third receiving process.

[0180] In the third example of the configuration shown in Figure 12, the transition period determination unit 214 determines whether the operation at that time is the current system (pre-transition) based on the signal supplied from the TMCC demodulation / decoding unit 212, and outputs a switching signal according to the result of that determination. However, as with the second example of the configuration shown in Figure 10, it may be set externally. Specifically, for example, the firmware of the television set may set a switching signal indicating the current system (pre-transition) for selectors 241 and 242.

[0181] Furthermore, while Figure 13 shows an example where next-generation 4K broadcasts are received by the dual-type receiving device 20D during the transition period, current 2K broadcasts may also be received.

[0182] <2. Variant>

[0183] (Examples of other broadcasting methods) The above explanation described the ISDB-T system as a broadcasting method for terrestrial digital television broadcasting, but this technology may be applied to other broadcasting methods. Furthermore, it may be applied not only to terrestrial broadcasting, but also to other broadcasting methods such as satellite broadcasting using broadcasting satellites (BS) or communications satellites (CS), or cable broadcasting (CATV: Common Antenna Television).

[0184] (Other configurations of the receiving device) Furthermore, in the above description, the receiving device 20 (Figure 1) was described as being configured as a fixed receiver such as a television receiver or a set-top box (STB), but the fixed receiver may also include electronic devices such as recording devices, game consoles, personal computers, and network storage devices. Moreover, the receiving device 20 (Figure 1) is not limited to a fixed receiver, but may also include electronic devices such as mobile receivers such as smartphones, mobile phones, and tablet computers, in-vehicle equipment such as in-car televisions, and wearable computers such as head-mounted displays (HMDs).

[0185] Furthermore, the transmitting device 10 having the configuration shown in Figure 6 may be considered as a modulation device or modulation unit (e.g., a modulation circuit). Similarly, the receiving device 20 having the configuration shown in Figure 8, etc., may be considered as a demodulator or demodulation unit (e.g., a demodulation circuit or demodulation IC). Moreover, in the transmitting device 10 shown in Figure 6, the OFDM modulation unit 117 may be considered as a transmitting unit that transmits a broadcast signal via a transmitting antenna. Similarly, in the receiving device 20 having the configuration shown in Figure 8, etc., the OFDM demodulation unit 211 may be considered as a receiving unit that receives a broadcast signal via a receiving antenna.

[0186] (Configuration including communication lines) Furthermore, in the transmission system 1 (Figure 1), although not shown, various servers may be connected to a communication line such as the Internet, and the receiving device 20 (Figure 1) having a communication function may access the various servers via the communication line such as the Internet and perform bidirectional communication to receive various data such as content and applications.

[0187] (others) The terms used in this disclosure are examples only and do not intentionally exclude the use of other terms. For example, in the above description, "frame" may be replaced with other terms such as "packet."

[0188] Furthermore, in this disclosure, "2K video" refers to video corresponding to a screen resolution of approximately 1920 x 1080 pixels, and "4K video" refers to video corresponding to a screen resolution of approximately 3840 x 2160 pixels. In addition, the above explanation describes 2K content of 2K video transmitted by current 2K broadcasting (current system) and 4K content of 4K video transmitted by next-generation 4K broadcasting (next-generation system) as broadcast content. However, broadcast content transmitted by the next-generation system may also be even higher quality content such as 8K video. However, "8K video" refers to video corresponding to a screen resolution of approximately 7680 x 4320 pixels.

[0189] <3. Computer Configuration>

[0190] The series of processes described above can be executed by hardware or by software. When the series of processes are executed by software, the programs that make up the software are installed on the computer. Figure 14 shows an example of the hardware configuration of a computer that executes the series of processes described above by program.

[0191] In computer 1000, the CPU (Central Processing Unit) 1001, ROM (Read Only Memory) 1002, and RAM (Random Access Memory) 1003 are interconnected by a bus 1004. An input / output interface 1005 is further connected to the bus 1004. An input / output interface 1005 is connected to an input unit 1006, an output unit 1007, a recording unit 1008, a communication unit 1009, and a drive 1010.

[0192] The input unit 1006 consists of a keyboard, mouse, microphone, etc. The output unit 1007 consists of a display, speaker, etc. The recording unit 1008 consists of a hard disk, non-volatile memory, etc. The communication unit 1009 consists of a network interface, etc. The drive 1010 drives a removable recording medium 1011 such as a magnetic disk, optical disk, magneto-optical disk, or semiconductor memory.

[0193] In the computer 1000 configured as described above, the CPU 1001 loads the programs stored in the ROM 1002 and the recording unit 1008 into the RAM 1003 via the input / output interface 1005 and the bus 1004, and executes them, thereby performing the series of processes described above.

[0194] The program executed by computer 1000 (CPU 1001) can be provided by recording it on a removable recording medium 1011, such as a packaged media. The program can also be provided via wired or wireless transmission media, such as a local area network, the internet, or digital satellite broadcasting.

[0195] In computer 1000, programs can be installed in the recording unit 1008 via the input / output interface 1005 by inserting the removable recording medium 1011 into the drive 1010. Alternatively, programs can be received by the communication unit 1009 via a wired or wireless transmission medium and installed in the recording unit 1008. Furthermore, programs can be pre-installed in the ROM 1002 or the recording unit 1008.

[0196] In this disclosure, the processing performed by a computer according to a program does not necessarily have to be performed chronologically in the order described in the flowchart. That is, the processing performed by a computer according to a program includes processing that is performed in parallel or individually (e.g., parallel processing or processing by objects). Furthermore, the program may be processed by one computer (processor) or may be processed in a distributed manner by multiple computers.

[0197] Furthermore, the embodiments of this technology are not limited to those described above, and various modifications are possible without departing from the spirit of this technology.

[0198] Furthermore, this technology can be configured as follows:

[0199] (1) The physical layer frame includes a first time interleaver that performs a first time interleave in accordance with a first scheme on error correction code blocks to be included as data frames, The error correction code block conforms to the second method, When the first time interleaver performs the first time interleave, it applies a pointer indicating the offset of the starting position of the error correction code block included at the beginning of the data frame. Transmitter. (2) The unit further comprises a transmitting unit that transmits the aforementioned physical layer frame as a broadcast signal to which a hierarchical division multiplexing scheme is applied. The transmitting device described in (1) above. (3) The transmitting unit transmits the physical layer frame, which includes the data frame and the transmission control signal. The aforementioned pointer is included in the transmission control signal The transmitting device described in (2) above. (4) The second method includes a next-generation method of the first method, The first time interleaver performs the first time interleave during the transition period between the first and second methods. The transmitting device described in (2) or (3) above. (5) The system further comprises a second time interleaver that performs a second time interleaving in accordance with the second method described above, The second time interleaver performs the second time interleave after the transition to the second method. The transmitting device described in (4) above. (6) Based on a switching signal indicating whether it is the transition period, the system switches from the first time interleaver to the second time interleaver. The transmitting device described in (5) above. (7) The transmitting unit transmits the physical layer frame, which includes the data frame and the transmission control signal. The switching signal is included in the transmission control signal. The transmitting device described in (6) above. (8) The first method includes the ISDB-T method, The second method includes a next-generation method of the ISDB-T method. The transmitting device described in (4) above. (9) The aforementioned physical layer frame includes an OFDM frame, The error correction code block includes an FEC block, The aforementioned pointer includes an FEC block pointer. A transmitting device as described in any of (1) to (8) above. (10) The transmitting device, When performing time interleaving in accordance with the first method on an error correction code block in accordance with the second method, which is included as a data frame in the physical layer frame, a pointer indicating the offset of the starting position of the error correction code block included at the beginning of the data frame is applied. Sending method. (11) A transmitting device comprising a time interleaver that applies a pointer indicating the offset of the starting position of the error correction code block included at the beginning of the data frame when performing a first time interleave in accordance with the first method on an error correction code block in accordance with a second method to be included as a data frame in a physical layer frame. The system includes a first time deinterleaver that performs a first time deinterleave, which restores the error correction code blocks extracted from the physical layer frame transmitted from the system, after the first time interleaving, back to their original time order according to the offset. Receiving device. (12) The system further includes a receiving unit that receives the physical layer frame transmitted as a broadcast signal using a hierarchical division multiplexing scheme. The receiving device described in (11) above. (13) The receiving unit receives the physical layer frame, which includes the data frame and the transmission control signal. The aforementioned pointer is included in the transmission control signal The receiving device described in (12) above. (14) The second method includes a next-generation method of the first method, The first time deinterleaver performs the first time deinterleaving during the transition period between the first and second methods. The receiving device described in (12) or (13) above. (15) The system further comprises a second time deinterleaver that performs a second time deinterleave in accordance with the second method described above, The second time deinterleaver performs the second time deinterleaving after the transition to the second method. The receiving device described in (14) above. (16) Based on a switching signal indicating whether it is the transition period, the system switches from the first time deinterleaver to the second time deinterleaver. The receiving device described in (15) above. (17) The receiving unit receives the physical layer frame, which includes the data frame and the transmission control signal. The switching signal is either included in the transmission control signal or set externally. The receiving device described in (16) above. (18) The first method includes the ISDB-T method, The second method includes a next-generation method of the ISDB-T method. The receiving device described in (14) above. (19) The aforementioned physical layer frame includes an OFDM frame, The error correction code block includes an FEC block, The aforementioned pointer includes an FEC block pointer. The receiving device described in any of (11) to (18) above. (20) A receiving device that receives a physical layer frame transmitted from a transmitting device equipped with a time interleaver that applies a pointer indicating the offset of the starting position of the error correction code block included at the beginning of the data frame when performing time interleaving in accordance with the first method on an error correction code block included as a data frame in a second method, The error correction code blocks extracted from the physical layer frame after time interleaving are deinterleaved in time to return them to their original temporal order according to the offset. Reception method. [Explanation of Symbols]

[0200] 1 Transmission system, 10 Transmitting device, 11, 11-1 to 11-N Data processing device, 20, 20-1 to 20-M Receiving device, 20D Dual-type receiving device, 20L Current receiving device, 20N Next-generation receiving device, 111-1, 111-2 FEC unit, 112 Power control unit, 113 Adding unit, 114 Power normalization unit, 115-1, 115-2 Signal processing unit, 116 Selector, 117 OFDM modulation unit, 118 Selector, 119 FEC pointer calculation unit, 120-1, 120-2 TMCC generation unit, 121 Power control unit, 122 Adding unit, 123 Power normalization unit, 124 Selector, 141-1, 141-2 Hierarchical synthesis unit, 142-1, 142-2 Time interleaver, 143-1, 143-2 Frequency interleaver, 211 OFDM demodulator, 212 TMCC demodulator / decoder, 213 TMCC LDM demodulator, 214 Transition period determination unit, 215 Selector, 216 TMCC demodulator / decoder, 217-1, 217-2 Frequency deinterleaver, 218 Selector, 219 RAM, 220-1, 220-2 Time deinterleaver, 221 Selector, 222 RAM, 223 FEC demodulator / decoder, 224 FEC LDM demodulator, 225 Selector, 226 FEC demodulator / decoder, 241 Selector, 242 Selector, 1000 Computer, 1001 CPU

Claims

1. A first multiplexing unit multiplexes a signal of a first error correction code block conforming to a first method and a signal of a second error correction code block conforming to a second method, according to a hierarchical multiplexing scheme. A first time interleaver performs a first time interleave on the multiplexed signal in accordance with the first method, A second multiplexing unit multiplexes a first transmission control signal conforming to the first method and a second transmission control signal conforming to the second method, according to the aforementioned hierarchical multiplexing scheme. A second time interleaver performs a second time interleave on the second error correction code block in accordance with the second method, A transmitting unit that, in a first period, configures a first physical layer frame including the first error correction code block and the second error correction code block after the first time interleave, and the multiplexed first transmission control signal and the second transmission control signal, and transmits it as a broadcast signal. Equipped with, The transmitting unit, during the second period, configures a second physical layer frame including the second error correction code block and the second transmission control signal after the second time interleaving, and transmits it as a broadcast signal. The second error correction code block may be arranged across multiple first physical layer frames or second physical layer frames. The pointer included in the second transmission control signal indicates, in terms of the number of data carriers, the offset from the beginning of the first or second physical layer frame containing the pointer to the beginning position of the second error correction code block before time interleaving is performed on the second error correction code block. The pointer is included in the first physical layer frame during the first period and in the second physical layer frame during the second period, respectively. Transmitter.

2. The first method is the ISDB-T method, The second method described above is the next-generation method of the ISDB-T method described above. The transmitting device according to claim 1.

3. The first physical layer frame and the second physical layer frame are OFDM frames, The first error correction code block and the second error correction code block are FEC blocks, The aforementioned pointer is an FEC block pointer. The transmitting device according to claim 2.

4. The transmitting device, In accordance with the hierarchical multiplexing scheme, the signals of a first error correction code block conforming to the first scheme and the signals of a second error correction code block conforming to the second scheme are multiplexed together. The signal after multiplexing is subjected to a first time interleaving in accordance with the first method, In accordance with the aforementioned hierarchical multiplexing scheme, a first transmission control signal conforming to the first scheme and a second transmission control signal conforming to the second scheme are multiplexed. In the first period, a first physical layer frame is formed including the first error correction code block and the second error correction code block after the first time interleaving, and the multiplexed first transmission control signal and the second transmission control signal, and transmitted as a broadcast signal. Perform a second time interleaving in accordance with the second method on the second error correction code block, In the second period, a second physical layer frame is formed, including the second error correction code block and the second transmission control signal after the second time interleaving, and transmitted as a broadcast signal. Includes, The second error correction code block may be arranged across multiple first physical layer frames or second physical layer frames. The pointer included in the second transmission control signal indicates, in terms of the number of data carriers, the offset from the beginning of the first or second physical layer frame containing the pointer to the beginning position of the second error correction code block before time interleaving is performed on the second error correction code block. The pointer is included in the first physical layer frame during the first period and in the second physical layer frame during the second period, respectively. Sending method.

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