Method for processing LDM broadcast signal

Abstract

To keep down the amount of memory required for processing a LDM broadcast signal.SOLUTION: A method for processing a LDM broadcast signal includes a demodulation step S20 of demodulating a LDM signal, a first separation step S30 of separating a first demodulated LL signal from the demodulated LDM signal as a demodulated LL signal, and an error correction step S40 of performing error correction on at least one of the demodulated LDM signal and a signal related to the demodulated LL signal. The first separation step S30 includes a step of performing a hard determination on an amplitude-corrected LDM signal, which is an amplitude-corrected demodulated LDM signal, at a code point defined by a UL signal method, and a step of subtracting the amplitude-corrected LDM signal on which the hard determination was performed from the amplitude-corrected LDM signal.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a method for processing broadcast signals in a Layered Division Multiplexing (LDM) format. [Background technology]

[0002] Studies are being conducted on the advancement of terrestrial digital broadcasting. One of the proposals is the LDM method as shown in Non-Patent Document 1. This method superimposes an advanced method (4K broadcasting) signal on the same physical channel as ISDB-T (Integrated Services Digital Broadcasting-Terrestrial), which is terrestrial digital broadcasting. Specifically, terrestrial digital broadcasting (2K broadcasting) data is transmitted on the UL (Upper Layer), and advanced broadcasting data is transmitted on the LL (Lower Layer).

[0003] This method has the advantage that by adding 4K broadcasting to the physical channel used for existing 2K broadcasting, there is no need to use new frequencies and investment in transmission equipment is kept to a minimum.

[0004] On the receiving side, the UL signal data and the LL signal data must be demodulated separately. There are two demodulation methods: Successive Interference Cancellation (SIC) and Joint Detection (JD). [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] "Report on the Study of Advanced Digital Terrestrial Television Broadcasting System Application Technology: Transmission Line Coding System (Advanced Broadcasting Introduction System (LDM System))" [online], February 27, 2023, Information and Communications Council, Information and Communications Technology Subcommittee, Broadcasting System Committee, Digital Terrestrial Broadcasting System Advanced Working Group (19th meeting) materials, [Retrieved November 1, 2023], Internet,<https: / / www.soumu.go.jp / main_content / 000864783.pdf> [Non-Patent Document 2] "Report on the Study of Advanced Digital Terrestrial Television Broadcasting System Application Technology: Transmission Line Coding System (Advanced Terrestrial Broadcasting System)", [online], February 27, 2023, Information and Communications Council, Information and Communications Technology Subcommittee, Broadcasting System Committee, Digital Terrestrial Broadcasting System Advanced Working Group (19th meeting) materials, [Retrieved November 1, 2023], Internet,<https: / / www.soumu.go.jp / main_content / 000864782.pdf> Summary of the Invention [Problem to be solved by the invention]

[0006] However, the method described in Reference 5 of Non-Patent Document 1 requires, in addition to a memory used for the process of decoding the UL signal, a memory used for regenerating the UL signal, a memory used for delaying data until the regeneration of the UL signal is completed in order to remove the UL signal, and a memory used for decoding the LL signal, which results in a problem of a significant increase in the amount of memory required.

[0007] In response to this, there is a method for reducing delay memory by matching the segment configuration between UL signals and LL signals and using the same time interleaving and frequency interleaving, as described in Reference Material 5 of Non-Patent Document 1. However, this method has the problem that it is always necessary to adopt the same segment configuration and interleaving for UL signals and LL signals, resulting in poor flexibility in transmission parameters.

[0008] In addition, the hierarchical reallocation method described in Reference Material 5 of Non-Patent Document 1 increases the flexibility of segment configuration, but has the problem that it requires the addition of a large memory capacity equivalent to one frame when decoding on the receiving side.

[0009] An object of the present disclosure is to reduce the amount of memory required for processing LDM-based broadcast signals. [Means for solving the problem]

[0010] A method for processing an LDM-based broadcast signal in one embodiment of the present disclosure is a method for processing an LDM-based broadcast signal in which a UL signal, which is a broadcast signal of a first system, and an LL signal, which is a broadcast signal of a second system and has a lower power level than the UL signal, are superimposed on one physical channel, the method including: a demodulation step of demodulating the LDM signal, which is the broadcast signal of the LDM system; a first separation step of separating a first demodulated LL signal from the demodulated LDM signal, which is the LDM signal demodulated in the demodulation step, as a demodulated LL signal, which is the LL signal demodulated in the demodulation step; and an error correction step of performing error correction on at least one of the demodulated LDM signal and a signal related to the LL signal demodulated in the demodulation step, the error correction step including at least one of a first deinterleaving step and a second deinterleaving step, and at least one of a first decoding step and a second decoding step, and in the first deinterleaving step, a demodulated UL signal related to the UL signal is generated from the demodulated LDM signal. in the second deinterleaving step, a UL deinterleaving process is performed which is a deinterleaving process on the first demodulated LL signal, in the first decoding step, a deinterleaved LDM signal which is the demodulated LDM signal which has been subjected to the UL deinterleaving process is decoded, in the second decoding step, the deinterleaved demodulated LL signal is decoded, and the first separation step includes a UL amplitude correction step which performs amplitude correction on the demodulated LDM signal, a first hard decision step which performs a hard decision on the amplitude-corrected LDM signal which is the amplitude-corrected demodulated LDM signal at a code point determined by the method of the UL signal, a first difference step which subtracts the amplitude-corrected LDM signal on which the hard decision has been performed from the amplitude-corrected LDM signal, and a first LL amplitude correction step which performs amplitude correction on the first difference signal obtained in the first difference step to generate the first demodulated LL signal.

[0011] These comprehensive or specific aspects may be realized by a system, a method, an integrated circuit, a computer program, or a recording medium such as a computer-readable CD-ROM, or may be realized by any combination of the system, the method, the integrated circuit, the computer program, and the recording medium. Effect of the Invention

[0012] According to the present disclosure, it is possible to reduce the amount of memory required for processing LDM broadcast signals. [Brief description of the drawings]

[0013] [Figure 1] 2 is a block diagram showing a functional configuration of a receiving device according to the first embodiment. FIG. [Diagram 2] 2 is a block diagram showing a functional configuration of a demodulation unit included in the receiving device according to the first embodiment. FIG. [Diagram 3] 4 is a block diagram showing a functional configuration of a first separation unit included in the receiving device according to the first embodiment. FIG. [Figure 4] 4 is a block diagram showing a functional configuration of a first error correction unit included in the receiving device according to the first embodiment. FIG. [Diagram 5] 4 is a block diagram showing a functional configuration of a second error correction unit included in the receiving device according to the first embodiment. FIG. [Figure 6] 4 is a flowchart showing a method for processing a broadcast signal in the LDM system according to the first embodiment. [Figure 7] 5 is a flowchart showing a first separation step in the method for processing a broadcast signal in the LDM system according to the first embodiment. [Figure 8] 5 is a flowchart showing error correction steps in the processing method for a broadcast signal of the LDM system according to the first embodiment. [Figure 9] FIG. 11 is a block diagram showing a functional configuration of a receiving device according to a second embodiment. [Figure 10] FIG. 11 is a diagram showing an example of a parameter indicating a time interleaving length of a UL signal and an LL signal. [Figure 11]FIG. 11 is a block diagram showing a functional configuration of a receiving device according to a third embodiment. [Figure 12] 13 is a block diagram showing a functional configuration of a second separation unit included in a receiving device according to the third embodiment. FIG. [Figure 13] 11 is a diagram showing a first example of parameters included in the transmission control information. [Figure 14] FIG. 11 is a diagram showing a second example of parameters included in the transmission control information. [Figure 15] FIG. 13 is a diagram showing a third example of parameters included in the transmission control information. [Figure 16] FIG. 13 is a diagram showing a fourth example of parameters included in the transmission control information. [Figure 17] FIG. 13 is a diagram showing a fifth example of parameters included in the transmission control information. [Figure 18] FIG. 13 is a diagram showing a sixth example of parameters included in the transmission control information. [Figure 19] 13 is a flowchart showing a second separation step in the processing method for an LDM broadcast signal according to the third embodiment. [Figure 20] FIG. 13 is a block diagram showing a functional configuration of a receiving device according to a fourth embodiment. [Figure 21] FIG. 13 is a block diagram showing a functional configuration of an encoding unit included in a receiving device according to a fourth embodiment. [Figure 22] FIG. 13 is a block diagram showing a functional configuration of a third separation unit included in a receiving device according to the fourth embodiment. [Figure 23] FIG. 13 is a block diagram showing a functional configuration of a receiving device according to a modification of the fourth embodiment. [Figure 24] 13 is a flowchart showing a third separation step in the processing method for an LDM broadcast signal according to the fourth embodiment. [Diagram 25] FIG. 13 is a block diagram showing a functional configuration of a receiving device according to a fifth embodiment. [Figure 26] FIG. 23 is a block diagram showing a functional configuration of a receiving device according to a sixth embodiment. [Figure 27] FIG. 23 is a block diagram showing a functional configuration of a receiving device according to a seventh embodiment. [Figure 28] FIG. 23 is a block diagram showing a functional configuration of a second decoding unit according to the seventh embodiment. [Figure 29] FIG. 23 is a block diagram showing a functional configuration of a receiving device according to an eighth embodiment. [Diagram 30] FIG. 23 is a block diagram showing a functional configuration of a receiving device according to a ninth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that each of the embodiments described below shows a specific example of the present disclosure. The numerical values, shapes, materials, components, the arrangement and connection forms of the components, steps, and the order of steps shown in the following embodiments are merely examples and are not intended to limit the present disclosure. In addition, among the components in the following embodiments, components that are not described in the independent claims showing the realization of one embodiment of the present disclosure are described as optional components. The realization of the present disclosure is not limited to the current independent claims, and may also be expressed by other independent claims.

[0015] Note that each drawing is a schematic diagram and is not necessarily a precise illustration. In addition, in each drawing, the same reference numerals are used for substantially the same configurations, and duplicated explanations may be omitted or simplified.

[0016] (Embodiment 1) A method for processing a broadcast signal in the LDM system according to a first embodiment and a receiving device using the same will be described.

[0017] [1-1. Receiving device] A receiving device according to the present embodiment will be described with reference to Figs. 1 to 5. Fig. 1 is a block diagram showing a functional configuration of a receiving device 10 according to the present embodiment. Fig. 2 is a block diagram showing a functional configuration of a demodulation unit 20 included in the receiving device 10 according to the present embodiment. Fig. 3 is a block diagram showing a functional configuration of a first separation unit 30 included in the receiving device 10 according to the present embodiment. Figs. 4 and 5 are block diagrams showing the functional configurations of a first error correction unit 40 and a second error correction unit 50 included in the receiving device 10 according to the present embodiment, respectively.

[0018] The receiving device 10 according to the present embodiment receives an LDM broadcast signal in which an UL (Upper Layer) signal, which is a broadcast signal of a first system, and an LL (Lower Layer) signal, which is a broadcast signal of a second system and has a lower power level than the UL signal, are superimposed on one physical channel. In the following, an example will be described in which an ISDB-T signal is used as the UL signal, which is a broadcast signal of the first system, and an advanced system (4K broadcast) signal is used as the LL signal, which is a broadcast signal of the second system. In the following, an LDM broadcast signal in which a UL signal and an LL signal are superimposed on the same physical channel is also referred to as an LDM signal.

[0019] As shown in FIG. 1, the receiving device 10 includes, as functional units, an ADC unit 11, a demodulation unit 20, a first separation unit 30, an error correction unit 12, a memory 13, and a memory control unit 14.

[0020] The ADC unit 11 is a processing unit that performs analog-to-digital conversion of a signal related to an LDM signal. In this embodiment, an RF unit (not shown) selects the frequency of one physical channel from an RF (Radio frequency) signal input from an antenna (not shown). This selected RF signal is converted to an IF (Intermediate frequency) signal and input to the ADC unit 11. The ADC unit 11 performs analog-to-digital conversion of the IF signal and outputs it to the demodulation unit 20. Hereinafter, the signal related to the LDM signal input to the demodulation unit 20 will also be simply referred to as the LDM signal.

[0021] The demodulation unit 20 is a processing unit that demodulates an LDM signal, which is a broadcast signal of the LDM system. As shown in Fig. 2, the demodulation unit 20 has a time axis processing unit 21, an FFT (Fast Fourier Transform) unit 22, a channel characteristic estimation unit 23, an equalization unit 24, and a TMCC (Transmission Multiplexing Configuration Control) / AC (Auxiliary Channel) decoding unit 25.

[0022] The time axis processing unit 21 is a processing unit that performs time axis processing of the IF signal. In this embodiment, the time axis processing unit 21 converts the IF signal into a baseband signal. Furthermore, the time axis processing unit 21 detects the symbol position of an OFDM (Orthogonal Frequency Division Multiplexing) symbol of the ISDB-T signal, and outputs the symbol position to the FFT unit 22.

[0023] The FFT unit 22 is a processing unit that performs FFT processing on the signal. In this embodiment, the FFT processing is performed based on the symbol position of the OFDM symbol, and the signal in the time axis domain is converted into a signal in the frequency axis domain. The FFT unit 22 outputs the signal in the frequency axis domain to each of the transmission path characteristics estimation unit 23, the equalization unit 24, and the TMCC / AC decoding unit 25.

[0024] The TMCC / AC decoding unit 25 is a processing unit that performs decoding on the signal in the frequency axis domain. The TMCC / AC decoding unit 25 performs decoding on the TMCC carrier and the AC carrier included in the OFDM frame of ISDB-T, and extracts the transmission control information transmitted using the TMCC carrier and the transmission control information transmitted using the AC carrier. The TMCC / AC decoding unit 25 outputs the extracted transmission control information to each processing unit such as the error correction unit 12.

[0025] The transmission control information is referred to in each processing unit of the receiving device 10, and is also output to a control unit (not shown).

[0026] The transmission path characteristic estimation unit 23 is a processing unit that estimates the characteristics of the transmission path through which the signal related to the LDM signal is transmitted. In this embodiment, the transmission path characteristic estimation unit 23 estimates the transmission path characteristic of the LDM signal based on the SP (Scattered Pilot) signals that are dispersedly inserted into the OFDM frame of ISDB-T, and outputs the estimation result to the equalization unit 24.

[0027] The equalization unit 24 is a processing unit that corrects distortion in the amplitude and phase of the signal that has been FFT processed by the FFT unit 22. The output of the equalization unit 24 is output to the first separation unit 30.

[0028] 1 is a processing unit that separates a first demodulated LL signal as a demodulated LL signal that is an LL signal demodulated by the demodulator 20 from a demodulated LDM signal that is an LDM signal demodulated by the demodulator 20. As shown in FIG. 3, the first separation unit 30 has a UL amplitude correction unit 31, a first hard decision unit 32, a first removal unit 33, and a first LL amplitude correction unit 34.

[0029] The UL amplitude correction unit 31 is a processing unit that performs amplitude correction on the demodulated LDM signal. In this embodiment, the UL amplitude correction unit 31 performs amplitude correction on the demodulated LDM signal based on information on the level (IL: Injection Level) of the LL signal superimposed on the demodulated LDM signal, so that the average power of the UL (Upper Layer) signal becomes 1. The amplitude-corrected LDM signal that is the output signal of the UL amplitude correction unit 31 is output to a first error correction unit 40 included in the error correction unit 12, and is also output to a first hard decision unit 32 and a first removal unit 33.

[0030] The first hard decision unit 32 is a processing unit that performs hard decision on the amplitude-corrected LDM signal, which is a demodulated LDM signal that has been amplitude-corrected, at a code point determined by the UL signal method. In this embodiment, the first hard decision unit 32 converts the amplitude-corrected LDM signal to the closest mapping point (i.e., makes a hard decision) based on mapping point information of the modulation method used in the UL signal, and outputs the converted amplitude-corrected LDM signal to the first removal unit 33.

[0031] The first removal unit 33 is a processing unit that subtracts, from the amplitude-corrected LDM signal, the amplitude-corrected LDM signal on which hard decision has been performed by the first hard decision unit 32. The first removal unit 33 subtracts the signal output from the first hard decision unit 32 from the signal output from the UL amplitude correction unit 31 to extract a first differential signal, which is the LL signal component, and outputs the first differential signal to the first LL amplitude correction unit 34.

[0032] The first LL amplitude correction unit 34 is a processing unit that generates a first demodulated LL signal by performing amplitude correction on the first differential signal obtained by the first removal unit 33. The first LL amplitude correction unit 34 performs amplitude correction based on the IL information so that the average power of the LL signal becomes 1, and outputs the amplitude-corrected first differential signal to the second error correction unit 50 included in the error correction unit 12.

[0033] 1 is a processing unit that performs error correction on at least one of the demodulated LDM signal and a signal related to the LL signal demodulated by the demodulation unit 20. The error correction unit 12 according to the present embodiment includes a first error correction unit 40 and a second error correction unit 50.

[0034] The first error correction unit 40 is a processing unit that performs error correction on the demodulated LDM signal. As shown in Fig. 4, the first error correction unit 40 has a first deinterleaving unit 41 and a first decoding unit 44. The first deinterleaving unit 41 is a processing unit that performs UL deinterleaving, which is a deinterleaving process on the demodulated UL signal related to the UL signal, out of the demodulated LDM signal. In this embodiment, the first deinterleaving unit 41 has a frequency DINT unit 42 and a time DINT unit 43.

[0035] The first decoding unit 44 is a processing unit that performs decoding on the deinterleaved LDM signal, which is a demodulated LDM signal that has been subjected to UL deinterleaving processing. In this embodiment, the first decoding unit 44 has a demapping unit 45, a bit DINT unit 46, an inner code decoding unit 47, a byte DINT unit 48, and an outer code decoding unit 49.

[0036] The frequency DINT unit 42 is a processing unit that performs frequency deinterleaving processing. In this embodiment, the frequency DINT unit 42 performs frequency deinterleaving on the demodulated LDM signal in accordance with the ISDB-T standard, and outputs the signal that has been subjected to frequency deinterleaving processing to the time DINT unit 43.

[0037] The time DINT unit 43 is a processing unit that performs time deinterleaving. In this embodiment, the time DINT unit 43 rearranges the order of the OFDM symbols (time deinterleaving) and outputs the signal that has been subjected to the time deinterleaving process to the demapping unit 45.

[0038] The demapping unit 45 is a processing unit that performs demapping processing. In this embodiment, the demapping unit 45 performs demapping processing on the input signal based on the modulation method used in the UL signal, calculates likelihood information for each modulated bit, and outputs a signal including the likelihood information to the bit DINT unit 46.

[0039] The bit DINT unit 46 is a processing unit that performs bit deinterleaving. In this embodiment, the bit DINT unit 46 rearranges the order of bits included in the input signal (bit deinterleaving), and outputs the signal that has been subjected to the bit deinterleaving process to the inner code decoding unit 47.

[0040] The inner code decoding unit 47 is a processing unit that performs inner code decoding processing. In this embodiment, the inner code decoding unit 47 performs Viterbi decoding processing on the input signal, performs error correction for each bit, and outputs the signal that has been error corrected to the byte DINT unit 48.

[0041] The byte DINT unit 48 is a processing unit that performs byte deinterleaving. In this embodiment, the byte DINT unit 48 performs signal order rearrangement in byte units (byte deinterleaving) on ​​the input signal, performs energy despreading, and outputs the signal that has been subjected to the byte deinterleaving process and the energy despreading process to the outer code decoding unit 49.

[0042] The outer code decoding unit 49 is a processing unit that performs an outer code decoding process. In this embodiment, the outer code decoding unit 49 performs an RS (Reed-Solomon) decoding process on the input signal to perform error correction on a byte basis, and outputs the error-corrected signal as a TS (Transport Stream) packet to a decoder (not shown).

[0043] The second error correction unit 50 is a processing unit that performs error correction on a signal related to the LL signal demodulated by the demodulation unit 20. As shown in FIG. 5, the second error correction unit 50 has a second deinterleaving unit 51 and a second decoding unit 54. The second deinterleaving unit 51 performs LL deinterleaving, which is a deinterleaving process on the first demodulated LL signal. In this embodiment, the second deinterleaving unit 51 has a frequency DINT unit 52 and a time DINT unit 53. The second decoding unit 54 is a processing unit that performs decoding on the deinterleaved demodulated LL signal. In this embodiment, the second decoding unit 54 has a demapping unit 55, a bit DINT unit 56, an inner code decoding unit 57, and an outer code decoding unit 59.

[0044] The frequency DINT unit 52 is a processing unit that performs frequency deinterleaving. In this embodiment, the frequency DINT unit 52 performs frequency deinterleaving on the demodulated LL signal in accordance with the standard of the LL signal, and outputs the signal that has been subjected to the frequency deinterleaving process to the time DINT unit 53.

[0045] The time DINT unit 53 is a processing unit that performs time deinterleaving. In this embodiment, the time DINT unit 53 rearranges the order of the OFDM symbols (time deinterleaving) and outputs the signal that has been subjected to the time deinterleaving process to the demapping unit 55.

[0046] The demapping unit 55 is a processing unit that performs demapping processing. In this embodiment, the demapping unit 55 performs demapping processing on the input signal based on the modulation method used in the LL signal, calculates likelihood information for each modulated bit, and outputs a signal including the likelihood information to the bit DINT unit 56.

[0047] The bit DINT unit 56 is a processing unit that performs bit deinterleaving. In this embodiment, the bit DINT unit 56 rearranges the order of bits included in the input signal (bit deinterleaving), and outputs the signal that has been subjected to the bit deinterleaving process to the inner code decoding unit 57.

[0048] The inner code decoding unit 57 is a processing unit that performs inner code decoding processing. In this embodiment, the inner code decoding unit 57 performs error correction on the input signal by LDPC (Low Density Parity Check) decoding, and outputs the signal that has been subjected to the error correction processing to the outer code decoding unit 59.

[0049] The outer code decoding unit 59 is a processing unit that performs outer code decoding processing. In this embodiment, the outer code decoding unit 59 performs error correction by BCH (Bose Chaudhuri Hocquenghem) decoding on the input signal, performs energy despreading, and outputs the error-corrected signal as a TLV (Type Length Value) packet to a decoder (not shown).

[0050] The memory 13 shown in Fig. 1 is a storage unit used to store temporary data in the process in the error correction unit 12. Specifically, the memory 13 is used in each deinterleaving process in the error correction unit 12. In this embodiment, the memory 13 has a capacity required in one of the first error correction unit 40 and the second error correction unit 50. In other words, if the memory amount required in the process in the first error correction unit 40 is N, the memory amount required in the process in the second error correction unit 50 is M, and the larger value of N and M is represented by Max(N,M), the capacity of the memory 13 may be Max(N,M). That is, for example, the memory 13 may have a first memory area and a second memory area. When a first memory area is used in the UL deinterleaving process in the first deinterleaving unit 41 and the decoding process in the first decoding unit 44, and a second memory area is used in the LL deinterleaving process in the second deinterleaving unit 51 and the decoding process in the second decoding unit 54, one of the first memory area and the second memory area may be included in the other. In this case, the capacity of the memory 13 can be set to Max(N,M).

[0051] As the memory 13, for example, a random access memory can be used.

[0052] The memory control unit 14 is a processing unit that controls allocation of memory areas of the memory 13 for each process of the error correction unit 12.

[0053] In the receiving device 10 according to the present embodiment, the first separation unit 30 uses hard decision to extract a demodulated UL signal from the demodulated LDM signal, and removes the demodulated UL signal extracted from the demodulated LDM signal to extract a demodulated LL signal. In this way, unlike the processing method described in Non-Patent Document 1, the processing method used in the receiving device 10 according to the present embodiment does not require re-encoding and interleaving of the decoded UL signal. Therefore, in the receiving device 10 according to the present embodiment, it is possible to reduce the amount of memory required to re-encode and interleave.

[0054] In addition, in the receiving device 10 of this embodiment, the error correction unit 12 performs at least one of UL deinterleaving processing in the first deinterleaving unit 41 and LL deinterleaving processing in the second deinterleaving unit 51, and at least one of decoding processing in the first decoding unit 44 and decoding processing in the second decoding unit 54.

[0055] The receiving device 10 has a first mode and a second mode as operation modes of the error correction unit 12. In the first mode, error correction is performed in the first error correction unit 40, and in the second mode, error correction is performed in the second error correction unit 50. The memory control unit 14 allocates a memory area of ​​the memory 13 to processing in the first error correction unit 40 in the first mode, and allocates a memory area of ​​the memory 13 to processing in the second error correction unit 50 in the second mode.

[0056] As a result, in the first mode, only error correction is performed on the UL signal, and TS packets for broadcast using the UL signal are output, whereas in the second mode, only error correction is performed on the LL signal, and TLV packets for broadcast using the LL signal are output.

[0057] In selecting the operation mode, the first mode or the second mode may be selected based on information other than the information transmitted using the LDM signal. The operation mode may be selected based on, for example, the user's channel selection information (i.e., information for selecting the UL signal broadcast or the LL signal broadcast). In addition, the operation mode may be selected based on the reception quality of the LDM signal as information other than the information transmitted using the LDM signal. Specifically, when the reception quality of the LDM signal is low, the quality of the LL signal may be degraded, so the first mode in which TS packets of the broadcast using the UL signal are output may be selected. In this case, the receiving device 10 may further include a reception quality estimation unit that estimates the reception quality. As the reception quality, for example, the C / N value may be used. In addition, in selecting the operation mode, the IL value may be used, and the first mode may be selected when the IL value is equal to or greater than a predetermined value, and the second mode may be selected when the IL value is smaller than the predetermined value.

[0058] According to this embodiment, the memory 13 can be shared by the first error correction unit 40 and the second error correction unit 50 in accordance with the user viewing either the UL signal broadcast or the LL signal broadcast. This makes it possible to reduce the amount of memory required for processing by the receiving device 10.

[0059] In the above example, the memory amount of the memory 13 is Max(N,M), but the sharing manner of the memory 13 in the receiving device 10 is not limited to this. Of the memory amounts used by the first error correction unit 40 and the second error correction unit 50, not all of the memory amount but only a part of the memory amount may be shared by the first error correction unit 40 and the second error correction unit 50. For example, the memory amount required for the time DINT unit 43 of the first error correction unit 40 and the time DINT unit 53 of the second error correction unit 50 may be shared by the memory 13, and the other processing units in the first error correction unit 40 and the second error correction unit 50 may have their own dedicated memory in addition to the memory 13.

[0060] The UL signal may also include a partial reception layer and a main layer that is a layer other than the partial reception layer. For example, the UL signal may include 13 segments, and the 13 segments may include a 1-segment portion that is one segment and a 12-segment portion other than the 1-segment portion. Here, the 1-segment portion is an example of a partial reception layer. In this case, error correction for the partial reception layer may be performed in either the first mode or the second operation mode. That is, error correction for the partial reception layer may always be performed. For example, the memory 13 may have a third memory area, a fourth memory area that does not overlap with the third memory area (that is, does not have a memory area in common with the third memory area), and a fifth memory area that does not overlap with the third memory area. In the UL deinterleaving process by the first deinterleaving unit 41 and the decoding process by the first decoding unit 44, the third memory area may be used in the process for the 1-segment portion, the fourth memory area may be used in the process for the 12-segment portion, and the fifth memory area may be used in the LL deinterleaving process by the second deinterleaving unit 51 and the decoding process by the second decoding unit 54. Here, one of the fourth memory area and the fifth memory area may be included in the other, and in the first mode, the third memory area and the fourth memory area may be used to perform error correction of the 1-segment portion and the 12-segment portion, and in the second mode, the third memory area and the fifth memory area may be used to perform error correction of the 1-segment portion and the demodulated LL signal.

[0061] The LL signal may also include a partially received layer and a main layer. In this case, error correction may always be performed on the partially received layer, as in the case where the UL signal includes a partially received layer and a main layer.

[0062] In this way, by securing the third memory area used for processing one segment portion so that it does not overlap with the fourth memory area and the fifth memory area, error correction of one segment portion can be performed in both the first and second operating modes.

[0063] The time interleaving length of the partial reception layer and the main layer may be different. For example, the time interleaving length of the partial reception layer may be the time interleaving length represented by parameter (4) shown in Fig. 10 (to be described later), and the time interleaving length of the main layer may be the time interleaving length represented by parameter (3) shown in Fig. 10 (to be described later).

[0064] [1-2. How LDM broadcast signals are processed] A method for processing a broadcast signal of the LDM system according to this embodiment will be described with reference to Figs. 6 to 8. Fig. 6 is a flowchart showing the method for processing a broadcast signal of the LDM system according to this embodiment. Fig. 7 is a flowchart showing a first separation step in the method for processing a broadcast signal of the LDM system according to this embodiment. Fig. 8 is a flowchart showing an error correction step in the method for processing a broadcast signal of the LDM system according to this embodiment.

[0065] The method for processing an LDM broadcast signal according to this embodiment includes a demodulation step S20, a first separation step S30, and an error correction step S40, as shown in Fig. 6. In this embodiment, the method for processing an LDM broadcast signal further includes an ADC step S10. In this embodiment, the method for processing an LDM broadcast signal is executed by a receiving device 10 according to this embodiment.

[0066] In the method for processing a broadcast signal in the LDM system, first, the ADC unit 11 of the receiving device 10 performs analog-to-digital conversion on a signal related to the LDM signal (ADC step S10).

[0067] Next, the demodulation section 20 of the receiving device 10 demodulates the LDM signal, which is a broadcast signal in the LDM system (demodulation step S20). In the demodulation step S20, the transmission control information is extracted from the LDM signal.

[0068] Next, the first separation unit 30 of the receiving device 10 separates a first demodulated LL signal, which is the LL signal demodulated in demodulation step S20, from the demodulated LDM signal, which is the LDM signal demodulated in demodulation step S20 (first separation step S30).

[0069] As shown in FIG. 7, the first separation step S30 includes a UL amplitude correction step S31, a first hard decision step S32, a first difference step S33, and a first LL amplitude correction step S34.

[0070] In the first separation step S30, first, the UL amplitude correction unit 31 of the first separation section 30 performs amplitude correction on the demodulated LDM signal (UL amplitude correction step S31).

[0071] Next, first hard decision unit 32 of first separation unit 30 performs hard decision on the amplitude-corrected LDM signal, which is the demodulated LDM signal whose amplitude has been corrected in UL amplitude correction step S31, at a code point defined by the UL signal method (first hard decision step S32).

[0072] Next, the first removal unit 33 of the first separation unit 30 subtracts the amplitude-corrected LDM signal on which hard decision has been performed from the amplitude-corrected LDM signal (first difference step S33).

[0073] Next, the first LL amplitude correction unit 34 of the first separation unit 30 performs amplitude correction on the first difference signal obtained in the first difference step S33, thereby generating a first demodulated LL signal (first LL amplitude correction step S34).

[0074] Subsequently, as shown in FIG. 6, the error correction unit 12 of the receiving device 10 performs error correction on at least one of the demodulated LDM signal and the signal related to the LL signal demodulated in the demodulation step (error correction step S40).

[0075] The error correction step S40 includes at least one of a first deinterleaving step S41 and a second deinterleaving step S51, and at least one of a first decoding step S44 and a second decoding step S54. In this embodiment, as shown in FIG. 8, the error correction step S40 includes only one of the first deinterleaving step S41 and the first decoding step S44, and the second deinterleaving step S51 and the second decoding step S54. In addition, the error correction step S40 has a first mode and a second mode as operation modes. The error correction step S40 further includes an operation mode selection step S12.

[0076] In the error correction step S40, first, the first mode or the second mode is selected as the operation mode (operation mode selection step S12). In this embodiment, in the operation mode selection step S12, the first mode or the second mode is selected based on information other than the information transmitted using the LDM signal.

[0077] In the operating mode selection step S12, when the first mode is selected (first mode in the operating mode selection step S12), the first deinterleaving unit 41 performs UL deinterleaving processing, which is a deinterleaving processing of the demodulated UL signal related to the UL signal among the demodulated LDM signals (first deinterleaving step S41).

[0078] Next, the first decoding unit 44 decodes the deinterleaved LDM signal, which is the demodulated LDM signal that has been subjected to the UL deinterleaving process (first decoding step S44).

[0079] On the other hand, if the second mode is selected in the operating mode selection step S12 (second mode in the operating mode selection step S12), the second deinterleaving unit 51 performs LL deinterleaving processing, which is a deinterleaving process on the LL signal after the first demodulation (second deinterleaving step S51).

[0080] Next, the second decoding unit 54 decodes the deinterleaved demodulated LL signal (second decoding step S54).

[0081] As described above, in the processing method of the LDM broadcast signal according to the present embodiment, in the first separation step S30, a demodulated UL signal is extracted from the demodulated LDM signal using hard decision, and the demodulated LL signal can be extracted by removing the demodulated UL signal extracted from the demodulated LDM signal. Thus, in the processing method of the LDM broadcast signal according to the present embodiment, unlike the processing method described in Non-Patent Document 1, it is not necessary to perform coding processing and interleaving processing again on the decoded UL signal. Therefore, in the processing method of the LDM broadcast signal according to the present embodiment, it is possible to reduce the amount of memory required to perform coding processing and interleaving processing again.

[0082] In the method for processing a broadcast signal of the LDM system according to the present embodiment, the error correction step S40 includes only one of the first deinterleaving step S41 and the first decoding step S44, and the second deinterleaving step S51 and the second decoding step S54. More specifically, the error correction step S40 has a first mode and a second mode as operation modes, and in the first mode, the first deinterleaving step S41 and the first decoding step S44 are executed, and in the second mode, the second deinterleaving step S51 and the second decoding step S54 are executed.

[0083] This allows the first deinterleaving step S41 and the first decoding step S44 and the second deinterleaving step S51 and the second decoding step S54 to share the memory 13 in accordance with whether the user is viewing the UL signal broadcast or the LL signal broadcast, thereby reducing the amount of memory required for processing by the receiving device 10.

[0084] For example, in the error correction step S40, the memory 13 for storing temporary data may be used, and the memory 13 may have a first memory area and a second memory area. In the first deinterleaving step S41 and the first decoding step S44, the first memory area may be used, and in the second deinterleaving step S51 and the second decoding step S54, the second memory area may be used, and one of the first memory area and the second memory area may be included in the other.

[0085] The memory 13 may also have a third memory area, a fourth memory area not overlapping with the third memory area, and a fifth memory area not overlapping with the third memory area. The UL signal may include 13 segments, and the 13 segments may include a 1-segment portion that is one segment, and 12-segment portions other than the 1-segment portion. In the first deinterleaving step S41 and the first decoding step S44, the third memory area may be used in the processing of the 1-segment portion, the fourth memory area may be used in the processing of the 12-segment portion, and the fifth memory area may be used in the second deinterleaving step and the second decoding step, and one of the fourth memory area and the fifth memory area may be included in the other. In the first mode, the third memory area and the fourth memory area may be used to perform error correction of the 1-segment portion and the 12-segment portion, and in the second mode, the third memory area and the fifth memory area may be used to perform error correction of the 1-segment portion and the demodulated LL signal.

[0086] In this way, by securing the third memory area used for processing one segment portion so that it does not overlap with the fourth memory area and the fifth memory area, error correction of one segment portion can be performed in both the first and second operating modes.

[0087] (Embodiment 2) A method for processing broadcast signals of the LDM system according to the second embodiment and a receiving device using the same will be described. The method for processing broadcast signals of the LDM system according to this embodiment differs from the method for processing broadcast signals of the LDM system according to the first embodiment mainly in that error correction processing is performed based on the time interleaving length of the UL signal and the LL signal. The method for processing broadcast signals of the LDM system and the receiving device according to this embodiment will be described below, focusing on the differences from the method for processing broadcast signals of the LDM system and the receiving device 10 according to the first embodiment.

[0088] [2-1. Receiving device] The receiving device according to this embodiment will be described with reference to Fig. 9. Fig. 9 is a block diagram showing the functional configuration of receiving device 110 according to this embodiment.

[0089] 9, the receiving device 110 includes, as functional units, an ADC unit 11, a demodulation unit 20, a first separation unit 30, an error correction unit 12, a memory 13, and a memory control unit 14, similarly to the receiving device 10 according to the first embodiment. The receiving device 110 according to the present embodiment further includes a parameter determination unit 115.

[0090] The parameter determination unit 115 is a processing unit that performs a determination based on parameters included in the LDM signal. In this embodiment, the parameter determination unit 115 performs the determination by referring to parameters included in the transmission control information extracted by the demodulation unit 20. Specifically, the parameter determination unit 115 performs the determination by referring to the time interleaving lengths of the UL signal and the LL signal, which are parameters included in the transmission control information.

[0091] An example of parameters indicating the time interleave length of a UL signal and an LL signal will be described with reference to Fig. 10. Fig. 10 is a diagram showing an example of parameters indicating the time interleave length of a UL signal and an LL signal. In Fig. 10, the time interleave length indicated by each of parameters (1) to (4) indicating the time interleave length is shown. Fig. 10 shows the time interleave length for three modes, mode 1 to mode 3. Mode 1, mode 2, and mode 3 are modes corresponding to FFT sizes used in broadcast signals of 2k (2048 points), 4k (4096 points), and 8k (8192 points), respectively.

[0092] For example, when the parameter is (1), the time interleave length is 0 in any of modes 1 to 3. When the parameter is (4), the time interleave length is the longest. Specifically, when the parameter is (4), the time interleave length is 16 in mode 1, 8 in mode 2, and 4 in mode 3. The time interleave length of each mode for each parameter is set so that the same amount of memory is required for time deinterleaving processing in each mode for each parameter.

[0093] When the parameter is (4), that is, when the time interleave length is the longest, the memory amount required for time deinterleaving is the largest. When the parameter is (3), the memory amount required for time deinterleaving is half the memory amount required for time deinterleaving when the parameter is (4). When the parameter is (2), the memory amount required for time deinterleaving is 1 / 4 of the memory amount required for time deinterleaving when the parameter is (4). When the parameter is (1), the time interleave length is 0, so the memory amount required for time deinterleaving is 0.

[0094] The memory 13 has a memory amount required for performing error correction of at least one of the UL signal and the LL signal. For example, the memory 13 has a memory amount required when the parameter indicating the time interleaving length of the UL signal is (4).

[0095] In this embodiment, the LDM signal includes a UL parameter indicating the time interleaving length of the UL signal and a LL parameter indicating the time interleaving length of the LL signal. In this embodiment, both the UL parameter and the LL parameter are defined as shown in FIG.

[0096] The parameter determination unit 115 according to this embodiment determines whether the UL parameter indicates the longest time interleaving length, and determines whether the LL parameter indicates the longest time interleaving length. When the parameters are as shown in Fig. 10, the parameter determination unit 115 determines whether the UL parameter is (4), and determines whether the LL parameter is (4).

[0097] The result of the determination by the parameter determination unit 115 is output to the error correction unit 12 and the memory control unit 14.

[0098] In this embodiment, the error correction unit 12 has a third mode and a fourth mode as operation modes.

[0099] When the parameter determination unit 115 determines that the UL parameters do not indicate the longest time interleave length and that the LL parameters do not indicate the longest time interleave length, the error correction unit 12 operates in the third mode. In the third mode, the error correction unit 12 performs both UL deinterleaving and LL deinterleaving. In this way, when it is determined that the UL parameters do not indicate the longest time interleave length and that the LL parameters do not indicate the longest time interleave length, the memory amounts required for time deinterleaving of the UL signal and the LL signal are each less than half the memory amount of the memory 13. Therefore, it is possible to perform time deinterleaving of both the UL signal and the LL signal with the memory amount possessed by the memory 13. The memory control unit 14 assigns a memory area corresponding to the UL parameters to the first error correction unit 40 and a memory area corresponding to the LL parameters to the second error correction unit 50. For example, the memory control unit 14 assigns to the first error correction unit 40 an amount of memory whose upper limit is the amount of memory required when the UL parameter is (3), and assigns to the second error correction unit 50 an amount of memory whose upper limit is the amount of memory required when the LL parameter is (3).

[0100] On the other hand, when the parameter determination unit 115 determines that at least one of the UL parameters and the LL parameters indicates the longest time interleaving length, the error correction unit 12 operates in a fourth mode. In the fourth mode, the error correction unit 12 performs UL deinterleaving processing or LL deinterleaving processing based on channel selection information not included in the LDM signal. In the fourth mode, the memory control unit 14 allocates a memory area to only one of the first error correction unit 40 and the second error correction unit 50. The amount of memory to be allocated to either the first error correction unit 40 or the second error correction unit 50 is determined based on, for example, the channel selection information of the user.

[0101] Here, when the UL parameter is (4), the memory amount required by the first error correction unit 40 is represented by N4, when the LL parameter is (4), the memory amount required by the second error correction unit 50 is represented by M4, when the UL parameter is (3), the memory amount required by the first error correction unit 40 is represented by N3, and when the LL parameter is (3), the memory amount required by the second error correction unit 50 is represented by M3. The memory amount S required for the memory 13 is represented by Max(N3+M3, Max(N4, M4)). For example, since the memory amount required in the third mode is equal to or less than N3+M3, the memory amount required for each of the first error correction unit 40 and the second error correction unit 50 can be allocated. In the fourth mode, for example, the memory amount of the memory 13 can be reduced by allocating the memory amount to only one of the first error correction unit 40 and the second error correction unit 50 according to the channel selection information.

[0102] [2-2. How LDM broadcast signals are processed] A method for processing a broadcast signal in the LDM system according to this embodiment will be described.

[0103] In the method for processing an LDM broadcast signal according to this embodiment, the error correction step also includes at least one of a first deinterleaving step and a second deinterleaving step, and at least one of a first decoding step and a second decoding step.

[0104] In this embodiment, the LDM signal includes a UL parameter indicating the time interleaving length of the UL signal and a LL parameter indicating the time interleaving length of the LL signal. If the UL parameter does not indicate the longest time interleaving length and the LL parameter does not indicate the longest time interleaving length, both the UL deinterleaving process and the LL deinterleaving process are performed in the error correction step.

[0105] On the other hand, when at least one of the UL parameters and the LL parameters indicates the longest time interleaving length, in the error correction step, UL deinterleaving or LL deinterleaving is performed based on channel selection information not included in the LDM signal.

[0106] Thereby, for example, by performing only one of UL deinterleaving and LL deinterleaving in accordance with channel selection information, it is possible to reduce the amount of memory required in the error correction step.

[0107] In addition, in the error correction step, a memory 13 for storing temporary data is used, and the memory 13 may have a sixth memory area and a seventh memory area. In the UL deinterleaving process, the sixth memory area is used, and in the LL deinterleaving process, the seventh memory area is used. One of the sixth memory area and the seventh memory area may be included in the other. This allows the memory amount of the memory 13 to be reduced.

[0108] Also, the parameter determination unit 115 may be configured not to include the time interleaving length of each partial reception layer in the UL parameters and the LL parameters in the determination. That is, the parameter determination unit 115 performs a determination using the time interleaving length of the UL parameters excluding the partial reception layer of the UL signal and the time interleaving length of the LL parameters excluding the partial reception layer of the LL signal, and if neither of them indicates the longest time interleaving length, the receiving device 110 operates in the third A mode, and if it is determined that at least one of them indicates the longest time interleaving length, the receiving device 110 operates in the fourth A mode. In this case, the memory 13 has a memory area dedicated to processing the partial reception layers of the UL signal and the LL signal. When the receiving device 110 operates in the third A mode, the memory control unit 14 allocates the memory area of ​​the memory 13 to both the first error correction unit 40 and the second error correction unit 50. When the receiving device 110 operates in the fourth A mode, the memory control unit 14 allocates the memory area of ​​the memory 13 to only one of the first error correction unit 40 and the second error correction unit 50. Whether the memory area is to be allocated to the first error correction unit 40 or the second error correction unit 50 is determined based on, for example, channel selection information of the user.

[0109] In current terrestrial digital broadcasting, the time interleaving length of the partial reception hierarchical layer is the longest (i.e., the parameter is (4)). In this case, by having memory 13 have a memory area dedicated to processing partial reception hierarchical layers, it is possible to secure a memory amount according to the time interleaving length of hierarchical layers other than the partial reception hierarchical layers in processing of hierarchical layers other than the partial reception hierarchical layers. In other words, since there is no need to constantly secure a memory amount according to the longest time interleaving length of the partial reception hierarchical layers in processing of hierarchical layers other than the partial reception hierarchical layers, the amount of memory used in processing of hierarchical layers other than the partial reception hierarchical layers can be reduced.

[0110] As described above, the time interleaving lengths of the partial reception layers of the UL signal and the LL signal are not determined by the parameter determination unit 115, and the memory 13 has a dedicated memory area for error correction of each partial reception layer, but of the time interleaving lengths of the partial reception layers of the UL signal and the LL signal, only the time interleaving length of the partial reception layer of the UL signal does not have to be used for the determination in the parameter determination unit 115. In this case, of the error correction of the partial reception layer of the UL signal and the error correction of the partial reception layer of the LL signal, the memory 13 only has a memory area dedicated to error correction of the partial reception layer of the UL signal, and does not have to have a memory area for error correction of the partial reception layer of the LL signal.

[0111] (Embodiment 3) A method for processing broadcast signals in the LDM system according to the third embodiment and a receiving device using the same will be described. The method for processing broadcast signals in the LDM system according to this embodiment differs from the method for processing broadcast signals in the LDM system according to the first embodiment mainly in that LL deinterleaving can also be performed in UL deinterleaving. The method for processing broadcast signals in the LDM system and the receiving device according to this embodiment will be described below, focusing on the differences from the method for processing broadcast signals in the LDM system and the receiving device 10 according to the first embodiment.

[0112] [3-1. Receiving device] The receiving device according to the present embodiment will be described with reference to Fig. 11 and Fig. 12. Fig. 11 is a block diagram showing the functional configuration of receiving device 210 according to the present embodiment. Fig. 12 is a block diagram showing the functional configuration of second separation unit 260 included in receiving device 210 according to the present embodiment.

[0113] 11, the receiving device 210 includes, as functional units, an ADC unit 11, a demodulation unit 20, a first separation unit 30, an error correction unit 212, a memory 13, and a memory control unit 14. The receiving device 210 according to the present embodiment further includes a parameter determination unit 215.

[0114] The parameter determination unit 215 according to this embodiment is a processing unit that performs a determination based on parameters included in the LDM signal. In this embodiment, the parameter determination unit 215 performs a determination by referring to parameters included in the transmission control information extracted by the demodulation unit 20. Specifically, the parameter determination unit 215 determines whether the UL deinterleaving process and the LL deinterleaving process are the same process or not. In this embodiment, the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are the same process when the hierarchical structure of the UL signal and the hierarchical structure of the LL signal are the same and the time interleaving length of the UL signal and the time interleaving length of the LL signal are the same. The result determined by the parameter determination unit 215 is output to the error correction unit 212 and the memory control unit 14.

[0115] The error correction unit 212 according to this embodiment has a fifth mode and a sixth mode as operation modes. The operation mode is selected based on the determination result of the parameter determination unit 215. When the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are the same process, the error correction unit 212 operates in the fifth mode. When the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are not the same process, the error correction unit 212 operates in the sixth mode.

[0116] In the fifth mode, UL deinterleaving is performed by the first deinterleaving unit 41. In this case, the memory control unit 14 allocates to the first deinterleaving unit 41 the amount of memory required for the UL deinterleaving.

[0117] The sixth mode includes a sixth UL mode and a sixth LL mode. In the sixth UL mode, the first deinterleaving unit 41 performs UL deinterleaving. In this case, the memory control unit 14 allocates the memory amount required for the UL deinterleaving to the first deinterleaving unit 41. In the sixth LL mode, the second deinterleaving unit 51 performs LL deinterleaving. In this case, the memory control unit 14 allocates the memory amount required for the LL deinterleaving to the second deinterleaving unit 51. The error correction unit 212 selects one of the sixth UL mode and the sixth LL mode, for example, based on channel selection information.

[0118] The error correction unit 212 includes a first error correction unit 40 , a second error correction unit 250 , and a second separation unit 260 .

[0119] The second separation unit 260 is a processing unit that extracts a second deinterleaved LL signal as a deinterleaved demodulated LL signal from the deinterleaved LDM signal deinterleaved by the first deinterleaving unit 41. As shown in FIG. 12, the second separation unit 260 has a second hard decision unit 262, a second removal unit 263, and a second LL amplitude correction unit 264.

[0120] The second hard decision unit 262 is a processing unit that performs hard decision on the deinterleaved LDM signal at a code point determined by the UL signal method. In this embodiment, the second hard decision unit 262 converts the deinterleaved LDM signal to the closest mapping point (i.e., hard decision) based on mapping point information of the modulation method used in the UL signal, and outputs the converted deinterleaved LDM signal to the second removal unit 263.

[0121] The second removal unit 263 is a processing unit that subtracts, from the deinterleaved LDM signal, the deinterleaved LDM signal on which hard decision has been performed by the second hard decision unit 262. The second removal unit 263 subtracts the signal output from the second hard decision unit 262 from the deinterleaved LDM signal to extract a second differential signal, which is the LL signal component, and outputs the second differential signal to the second LL amplitude correction unit 264.

[0122] The second LL amplitude correction unit 264 is a processing unit that generates a second deinterleaved LL signal by performing amplitude correction on the second differential signal obtained in the second removal unit 263. The second LL amplitude correction unit 264 performs amplitude correction based on the IL information so that the average power of the LL signal becomes 1, and outputs the amplitude-corrected second differential signal to the second error correction unit 250 included in the error correction unit 212.

[0123] The second error correction unit 250 shown in FIG. 11 includes a second deinterleaving unit 51, a second decoding unit 54, and a selection unit 255.

[0124] The selection unit 255 is a processing unit that selects a signal to be input to the second decoding unit 54. The selection unit 255 selects one of the signal input from the second deinterleaving unit 51 and the signal input from the second separating unit 260 based on the determination result of the parameter determination unit 215, i.e., the operation mode, and inputs the selected signal to the second decoding unit 54.

[0125] In the fifth mode, the selection unit 255 selects the signal input from the second separation unit 260 and inputs it to the second decoding unit 54. In this case, the second decoding unit 54 decodes the second deinterleaved LL signal as a deinterleaved demodulated LL signal. Furthermore, in the fifth mode, the first decoding unit 44 decodes the deinterleaved LDM signal. This makes it possible to output TS packets from the first error correction unit 40 and TVL packets from the second error correction unit 250 in the fifth mode.

[0126] In the sixth LL mode of the sixth mode, the selection unit 255 selects the signal input from the second deinterleaving unit 51 and inputs it to the second decoding unit 54. In this case, the second decoding unit 54 decodes the deinterleaved first demodulated LL signal as a deinterleaved demodulated LL signal.

[0127] Here, the operation of the receiving device 210 corresponding to each example of the parameters included in the transmission control information will be described with reference to Fig. 13 to Fig. 18. Fig. 13 to Fig. 18 are diagrams showing examples of parameters included in the transmission control information.

[0128] 13, the UL signal has a first partial reception layer with one segment and a first main layer with 12 segments, and the LL signal has a second main layer which is a single layer with 13 segments. In this case, only the first partial reception layer is frequency interleaved independently, so it is determined that the frequency interleaving of the UL signal and the LL signal are different, and error correction unit 212 operates in the sixth mode.

[0129] In the example shown in Fig. 14, the UL signal has a first partial reception layer with one segment and a first main layer with 12 segments, and the LL signal has a second partial reception layer with one segment and a second main layer with 12 segments. In this case, the UL signal and the LL signal have the same hierarchical structure, so the frequency interleaving in the UL signal and the LL signal is the same. However, the time interleaving length in each main layer of the UL signal and the LL signal is different, so the error correction unit 212 operates in the sixth mode.

[0130] In the example shown in Fig. 15, the UL signal has a first partial reception layer with one segment and a first main layer with 12 segments, and the LL signal has a second partial reception layer with one segment and a second main layer with 12 segments. In this case, the UL signal and the LL signal have the same layer configuration, so the frequency interleaving in the UL signal and the LL signal is the same. In addition, the time interleaving length in the UL signal and the LL signal is also the same, so the error correction unit 212 operates in the fifth mode.

[0131] In the example shown in Fig. 16, the UL signal has a first partial reception layer with one segment and a first main layer with twelve segments, and the LL signal has a second partial reception layer with one segment, a second sublayer with five segments, and a second main layer with seven segments. In this case, the hierarchical configurations of the UL signal and the LL signal are different, but frequency interleaving is performed collectively in layers other than the partial reception layer, so the frequency interleaving in the UL signal and the LL signal is the same. In addition, the time interleaving length in the first main layer of the UL signal and the second sublayer and second main layer of the LL signal are also the same, so the error correction unit 212 operates in the fifth mode.

[0132] In the example shown in Fig. 17, the UL signal has a first partial reception layer with 1 segment and a first main layer with 12 segments, and the LL signal has a second partial reception layer with 1 segment, a second sub-layer with 5 segments, and a second main layer with 7 segments. In this case, the frequency interleaving in the UL signal and the LL signal is the same as in the example shown in Fig. 16. Also, since the time interleaving lengths in the first main layer of the UL signal and the second main layer of the LL signal are different, the error correction unit 212 operates in the sixth mode.

[0133] In this embodiment as well, the memory 13 can be shared by the first error correction unit 40 and the second error correction unit 250 in accordance with viewing of either the UL signal broadcast or the LL signal broadcast based on channel selection information, etc. Furthermore, in the receiving device 210 according to this embodiment, packets of the UL signal and the LL signal can be output simultaneously depending on the parameters of the signals, thereby realizing a receiving device with a reduced circuit scale.

[0134] In the determination in parameter determining section 215, it is determined whether or not the frequency deinterleaving and time deinterleaving are the same for UL signals and LL signals in all layers, but the manner of determination is not limited to this.

[0135] It may be determined whether or not the frequency deinterleaving process and the time deinterleaving process are the same in some layers of the UL signal and the LL signal.

[0136] For example, in the example shown in Figure 14, each of the UL signal and the LL signal has a partial reception layer, the time interleaving length of each partial reception layer is the same, and the time interleaving length of each main layer is different. In this case, the frequency deinterleaving process and the time deinterleaving process are the same for each partial reception layer.

[0137] In the example shown in Figure 18, each of the UL signal and the LL signal has a partial reception layer, the time interleaving length of each main layer is the same, and the time interleaving length of each partial reception layer is different. In this case, the frequency deinterleaving process and the time deinterleaving process are the same for each main layer.

[0138] In the examples shown in these Figs. 14 and 18, the memory control unit 14 may allocate a memory amount to the processing of the first deinterleaving unit 41 for the error correction unit 212, and the selection unit 255 may select the output of the second separation unit 260 and output it to the second decoding unit 54. In this case, the second decoding unit 54 performs decoding only on the layer in which the frequency deinterleaving process and the time deinterleaving process are the same for the UL signal and the LL signal, and outputs the TLV packet. This makes it possible to output the TS packet of the UL signal while suppressing an increase in the required memory amount, and to output the TLV packet of the layer in the LL signal in which the frequency deinterleaving process and the time deinterleaving process are the same for the UL signal and the LL signal. Such an operation mode may also be an example of the fifth mode.

[0139] [3-2. How LDM broadcast signals are processed] A method for processing a broadcast signal in the LDM system according to this embodiment will be described.

[0140] In the method for processing an LDM broadcast signal according to this embodiment, the error correction step also includes at least one of a first deinterleaving step and a second deinterleaving step, and at least one of a first decoding step and a second decoding step.

[0141] The error correction step according to this embodiment has a fifth mode and a sixth mode as operation modes. When the UL deinterleaving process and the LL deinterleaving process are the same process, the error correction step operates in the fifth mode. In the fifth mode, the error correction step includes a second separation step of extracting a second deinterleaved LL signal as a deinterleaved demodulated LL signal from the deinterleaved LDM signal. Here, the second separation step will be described with reference to FIG. 19. FIG. 19 is a flowchart showing the second separation step in the processing method for a broadcast signal of the LDM system according to this embodiment.

[0142] As shown in FIG. 19, in the second separation step, second hard decision section 262 of second separation section 260 first performs hard decision on the deinterleaved LDM signal similar to that in first hard decision step S32 (second hard decision step S262).

[0143] Next, second removal section 263 of second separation section 260 subtracts the deinterleaved LDM signal on which hard decision has been performed from the deinterleaved LDM signal (second difference step S263).

[0144] Next, the second LL amplitude correction unit 264 of the second separation unit 260 performs amplitude correction on the second difference signal obtained in the second difference step S263, thereby generating a second deinterleaved LL signal (second LL amplitude correction step S264).

[0145] Furthermore, the error correction step includes a second decoding step, in which the second deinterleaved LL signal is decoded as a deinterleaved demodulated LL signal.

[0146] In this case, the error correction step may comprise a first decoding step.

[0147] As a result, when the UL deinterleaving process and the LL deinterleaving process are the same process, the first deinterleaving unit 41 can perform deinterleaving processes on both the UL signal and the LL signal. This makes it possible to reduce the amount of memory required for the deinterleaving process.

[0148] When the UL deinterleaving process and the LL deinterleaving process are not the same process, the error correction step operates in a sixth mode. The sixth mode includes a sixth UL mode and a sixth LL mode. In the sixth UL mode, the error correction step includes a first deinterleaving step. In the first deinterleaving step, the first deinterleaving unit 41 performs the UL deinterleaving process. In this case, the memory control unit 14 allocates the memory amount required for the UL deinterleaving process to the first deinterleaving unit 41. In the sixth LL mode, the error correction step includes a second deinterleaving step. In the second deinterleaving step, the second deinterleaving unit 51 performs the LL deinterleaving process. In this case, the memory control unit 14 allocates the memory amount required for the LL deinterleaving process to the second deinterleaving unit 51. In the error correction step, for example, one of the sixth UL mode and the sixth LL mode is selected based on the channel selection information.

[0149] In the error correction step, a memory 13 is used for storing temporary data, and the memory 13 has an eighth memory area and a ninth memory area. In the UL deinterleaving process, the eighth memory area is used, and in the LL deinterleaving process, the ninth memory area is used. One of the eighth memory area and the ninth memory area may be included in the other.

[0150] In this embodiment as well, the memory 13 can be shared between the first deinterleaving step and the second deinterleaving step in accordance with viewing of either the UL signal broadcast or the LL signal broadcast based on channel selection information, etc. Furthermore, in this embodiment, depending on the parameters of the UL signal and the LL signal, respective packets can be output simultaneously, thereby realizing a receiving device with a reduced circuit scale.

[0151] (Embodiment 4) A method for processing LDM-based broadcast signals according to the fourth embodiment and a receiving device using the same will be described. The method for processing LDM-based broadcast signals according to this embodiment differs from the method for processing LDM-based broadcast signals according to the third embodiment mainly in the method for extracting the LL signal. The method for processing LDM-based broadcast signals and the receiving device according to this embodiment will be described below, focusing on the differences from the method for processing LDM-based broadcast signals and the receiving device 210 according to the third embodiment.

[0152] [4-1. Receiving device] The receiving device according to the present embodiment will be described with reference to Figs. 20 to 22. Fig. 20 is a block diagram showing a functional configuration of receiving device 310 according to the present embodiment. Fig. 21 is a block diagram showing a functional configuration of encoding section 370 included in receiving device 310 according to the present embodiment. Fig. 22 is a block diagram showing a functional configuration of third separation section 360 included in receiving device 310 according to the present embodiment.

[0153] As shown in FIG. 20, the receiving device 310 includes, as functional units, an ADC unit 11, a demodulation unit 20, a first separation unit 30, an error correction unit 312, a memory 13, and a parameter determination unit 215.

[0154] The error correction unit 312 according to this embodiment has a seventh mode and an eighth mode as operation modes. The operation mode is selected based on the determination result of the parameter determination unit 215. When the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are the same process, the error correction unit 312 operates in the seventh mode. When the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are not the same process, the error correction unit 312 operates in the eighth mode.

[0155] In the seventh mode, the first deinterleaving unit 41 performs UL deinterleaving. The first deinterleaving unit 41 performs deinterleaving on the demodulated UL signal and the demodulated LL signal. The error correction unit 312 extracts the third deinterleaved LL signal as the demodulated LL signal deinterleaved by the first deinterleaving unit 41, and the second decoding unit 54 decodes the third deinterleaved LL signal.

[0156] In the eighth mode, the error correction unit 312 performs error correction on the demodulated UL signal by the first error correction unit 40, and performs error correction on the demodulated LL signal by the second error correction unit 250. In the eighth mode, only one of the UL signal and the LL signal may be received by performing error correction on only one of the demodulated UL signal and the demodulated LL signal. The signal to be received may be selected based on, for example, channel selection information.

[0157] In the seventh mode, the selection unit 255 of the second error correction unit 250 selects the third deinterleaved LL signal from the third separation unit 360 and outputs it to the second decoding unit 54, and in the eighth mode, selects the first deinterleaved LL signal from the second deinterleaving unit 51 and outputs it to the second decoding unit 54.

[0158] The error correction unit 312 includes a first error correction unit 40 , a second error correction unit 250 , a first delay unit 366 , a third separation unit 360 , and an encoding unit 370 .

[0159] The encoding unit 370 is a processing unit that performs encoding on the decoded UL signal obtained by decoding the deinterleaved LDM signal by the first decoding unit 44. In this embodiment, the encoding unit 370 performs encoding on the TS packet. The encoding unit 370 generates a re-encoded UL signal equivalent to a signal obtained by performing UL deinterleaving processing on the demodulated UL signal. In addition, the re-encoded UL signal generated by the encoding unit 370 is more faithful to the UL signal than the deinterleaved UL signal obtained by hard decision. As shown in FIG. 21, the encoding unit 370 has an outer code encoding unit 371, a byte INT unit 372, an inner code encoding unit 373, a bit INT unit 374, and a mapping unit 375.

[0160] The outer code encoding unit 371 is a processing unit that performs outer code encoding processing. In this embodiment, the outer code encoding unit 371 performs RS encoding on the decoded UL signal (TS packet in this embodiment) output from the first decoding unit 44 in accordance with the ISDB-T standard, and outputs the result to the byte INT unit 372.

[0161] The byte INT unit 372 is a processing unit that performs byte interleaving processing. In this embodiment, the byte INT unit 372 performs energy diffusion on the input signal, and also performs order rearrangement on a byte basis (byte interleaving), and outputs the signal to the inner code encoding unit 373.

[0162] The inner code encoding unit 373 is a processing unit that performs inner code encoding processing. In this embodiment, the inner code encoding unit 373 performs convolutional encoding on the input signal and outputs the signal to the bit INT unit 374.

[0163] The bit INT unit 374 is a processing unit that performs bit interleaving. In this embodiment, the bit INT unit 374 performs bit interleaving on the input signal and outputs the signal to the mapping unit 375.

[0164] The mapping unit 375 is a processing unit that performs mapping on the input signal. In this embodiment, the mapping unit 375 performs mapping in accordance with the mapping point of the modulation scheme used in the UL signal, and outputs the signal to the third separation unit 360.

[0165] The first delay unit 366 is a processing unit that performs delay processing on the deinterleaved LDM signal deinterleaved by the first deinterleaving unit 41. The first delay unit 366 temporarily stores the input deinterleaved LDM signal, and outputs it to the third separation unit 360 after a predetermined time has elapsed. The first delay unit 366 performs delay processing for the time required for processing in the first decoding unit 44 and the encoding unit 370. This makes it possible to substantially synchronize the deinterleaved LDM signal and the re-encoded UL signal corresponding to that signal.

[0166] The third separation unit 360 is a processing unit that extracts a third deinterleaved LL signal as a deinterleaved demodulated LL signal from the deinterleaved LDM signal deinterleaved by the first deinterleaving unit 41. As shown in FIG. 22, the third separation unit 360 has a third removal unit 363 and a third LL amplitude correction unit 364.

[0167] The third removal unit 363 is a processing unit that subtracts the re-encoded UL signal from the deinterleaved LDM signal. The third removal unit 363 extracts a third differential signal that is an LL signal component by subtracting the re-encoded UL signal from the deinterleaved LDM signal, and outputs the third differential signal to the third LL amplitude correction unit 364.

[0168] The third LL amplitude correction unit 364 is a processing unit that generates a third deinterleaved LL signal by performing amplitude correction on the third differential signal obtained in the third removal unit 363. The third LL amplitude correction unit 364 performs amplitude correction based on the IL information so that the average power of the LL signal becomes 1, and outputs the amplitude-corrected third differential signal to the second error correction unit 250 included in the error correction unit 312.

[0169] In the seventh mode, the selection unit 255 of the second error correction unit 250 selects the third deinterleaved LL signal from the third separation unit 360 and outputs it to the second decoding unit 54, and in the eighth mode, selects the first deinterleaved LL signal from the second deinterleaving unit 51 and outputs it to the second decoding unit 54.

[0170] In this embodiment, independent (that is, non-overlapping) memory areas of the memory 13 are allocated to the UL interleaving process and the LL interleaving process so that they can be performed simultaneously.

[0171] In this embodiment, in the seventh mode in which frequency deinterleaving and time deinterleaving are common to the UL signal and the LL signal, the UL signal component can be accurately separated and the accuracy of the LL signal component is improved by using a re-encoded UL signal in which errors have been reduced by performing error correction rather than hard decision on the UL signal in removing the UL signal component in the third separation unit 360. Also, in the seventh mode, unlike the method described in Non-Patent Document 1, there is no need to perform interleaving on the re-encoded UL signal, and therefore the amount of memory required for interleaving can be reduced.

[0172] In an eighth mode in which frequency deinterleaving and time deinterleaving are not common, only one of the UL signal and the LL signal can be received.

[0173] In the receiving device 310 according to this embodiment, the timing of the signal input from the first deinterleaving unit 41 of the second error correction unit 250 to the selection unit 255 may be adjusted. The configuration of the receiving device in which the timing of the signal input to the selection unit 255 is adjusted will be described with reference to Fig. 23. Fig. 23 is a block diagram showing the functional configuration of a receiving device 310a according to a modified example of this embodiment.

[0174] As shown in FIG. 23, a receiving device 310a according to the modified example includes, as functional units, an ADC unit 11, a demodulation unit 20, a first separation unit 30, an error correction unit 312a, a memory 13, and a parameter determination unit 215.

[0175] The error correction unit 312 a includes a first error correction unit 40 , a second error correction unit 250 a , a first delay unit 366 , a third separation unit 360 , and an encoding unit 370 .

[0176] The second error correction unit 250 a includes a second deinterleaving unit 51 , a second decoding unit 54 , a selection unit 255 , and a second delay unit 356 .

[0177] The second delay unit 356 is a processing unit that performs delay processing on the first deinterleaved LL signal deinterleaved by the second deinterleaving unit 51. The second delay unit 356 temporarily stores the input first deinterleaved LL signal, and outputs it to the selection unit 255 after a predetermined time has elapsed. In this modification, the second delay unit 356 performs delay processing for a time that matches the processing delay in the first delay unit 366 and the third separation unit 360. This allows the third deinterleaved LL signal input to the selection unit 255 to be substantially synchronized with the first deinterleaved LL signal.

[0178] [4-2. How LDM broadcasting signals are processed] A method for processing a broadcast signal in the LDM system according to this embodiment will be described.

[0179] In the method for processing an LDM broadcast signal according to this embodiment, the error correction step also includes at least one of a first deinterleaving step and a second deinterleaving step, and at least one of a first decoding step and a second decoding step.

[0180] The error correction step according to the present embodiment has a seventh mode and an eighth mode as operation modes. When the UL deinterleaving process and the LL deinterleaving process are the same process, the error correction step operates in the seventh mode. In the seventh mode, the error correction step includes a re-encoding step of encoding the decoded UL signal, which is the deinterleaved LDM signal decoded in the first decoding step, and a third separation step of extracting a third deinterleaved LL signal as a deinterleaved demodulated LL signal from the deinterleaved LDM signal.

[0181] Here, the third separation step will be described with reference to Fig. 24. Fig. 24 is a flowchart showing the third separation step in the method for processing a broadcast signal of the LDM system according to this embodiment.

[0182] As shown in FIG. 24, the third removal unit 363 of the third separation unit 360 subtracts the re-encoded UL signal from the deinterleaved LDM signal (third difference step S363).

[0183] Next, the third LL amplitude correction unit 364 of the third separation unit 360 performs amplitude correction on the third differential signal obtained in the third difference step S363, thereby generating a third deinterleaved LL signal (third LL amplitude correction step S364).

[0184] Furthermore, the error correction step includes a second decoding step, in which the third deinterleaved LL signal is decoded as the deinterleaved demodulated LL signal.

[0185] In this case, the error correction step comprises a first decoding step.

[0186] As a result, when the UL deinterleaving process and the LL deinterleaving process are the same process, the first deinterleaving unit 41 can perform deinterleaving processes on both the UL signal and the LL signal. This makes it possible to reduce the amount of memory required for the deinterleaving process.

[0187] The error correction step may include a first delay step between the first deinterleaving step and the third separation step, in which the deinterleaved LDM signal is delayed by the first delay unit 366. The error correction step may also include a second delay step between the second deinterleaving step and the second decoding step, in which the first deinterleaved LL signal is delayed by the second delay unit 356.

[0188] When the UL deinterleaving process and the LL deinterleaving process are not the same process, the error correction step operates in the eighth mode. In the eighth mode, the error correction unit 312 performs error correction of the demodulated UL signal by performing a first deinterleaving step and a first decoding step by the first error correction unit 40. In addition, the error correction unit 312 performs error correction of the demodulated LL signal by performing a second deinterleaving step and a second decoding step by the second error correction unit 50. In the eighth mode, only one of the UL signal and the LL signal may be received by performing error correction of only one of the demodulated UL signal and the demodulated LL signal. The signal to be received may be selected based on, for example, channel selection information.

[0189] The method for processing an LDM broadcast signal according to this embodiment provides the same effects as those of the receiving device 310 and the receiving device 310a.

[0190] (Embodiment 5) A method for processing broadcast signals in the LDM system according to the fifth embodiment and a receiving device using the same will be described. The method for processing broadcast signals in the LDM system according to this embodiment differs from the method for processing broadcast signals in the LDM system according to the fourth embodiment in controlling memory areas allocated to each deinterleave process. The method for processing broadcast signals in the LDM system and the receiving device according to this embodiment will be described below, focusing on the differences from the method for processing broadcast signals in the LDM system and the receiving device 310 according to the fourth embodiment.

[0191] The receiving device according to this embodiment will be described with reference to Fig. 25. Fig. 25 is a block diagram showing the functional configuration of receiving device 410 according to this embodiment.

[0192] 25, the receiving device 410 includes, as functional units, an ADC unit 11, a demodulation unit 20, a first separation unit 30, an error correction unit 312, a memory 13, and a parameter determination unit 215. The receiving device 410 according to the present embodiment further includes a memory control unit 14.

[0193] The memory 13 and the memory control unit 14 have the same configurations as the memory 13 and the memory control unit 14 according to the third embodiment, respectively.

[0194] The error correction unit 312 according to the present embodiment has a ninth mode and a tenth mode as operation modes.

[0195] The operation mode is selected based on the result of the determination by the parameter determination unit 215. If the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are the same process, the error correction unit 312 operates in the ninth mode. If the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are not the same process, the error correction unit 312 operates in the tenth mode.

[0196] In the ninth mode, UL deinterleaving is performed by the first deinterleaving unit 41. In this case, the memory control unit 14 allocates to the first deinterleaving unit 41 the amount of memory required for the UL deinterleaving.

[0197] The tenth mode includes a tenth UL mode and a tenth LL mode. In the tenth UL mode, the first deinterleaving unit 41 performs UL deinterleaving. In this case, the memory control unit 14 allocates the memory amount required for the UL deinterleaving to the first deinterleaving unit 41. In the tenth LL mode, the second deinterleaving unit 51 performs LL deinterleaving. In this case, the memory control unit 14 allocates the memory amount required for the LL deinterleaving to the second deinterleaving unit 51. The error correction unit 312 selects one of the tenth UL mode and the tenth LL mode, for example, based on channel selection information.

[0198] In the ninth mode, the selection unit 255 of the second error correction unit 250 selects the third deinterleaved LL signal from the third separation unit 360 and outputs it to the second decoding unit 54, and in the tenth mode, selects the first deinterleaved LL signal from the second deinterleaving unit 51 and outputs it to the second decoding unit 54.

[0199] In this embodiment, the memory 13 can be shared by the first error correction unit 40 and the second error correction unit 250 in accordance with viewing of either the UL signal broadcast or the LL signal broadcast based on channel selection information, etc. Furthermore, in the receiving device 410 according to this embodiment, packets of the UL signal and the LL signal can be output simultaneously depending on the parameters of the signals, thereby realizing a receiving device with a reduced circuit scale.

[0200] In the above, an example in which the memory 13 is shared between the UL deinterleaving process and the LL deinterleaving process has been shown, but at least a part of the memory amount required by the first delay unit 366 may also be shared. In this case, when operating in the ninth mode, the memory control unit 14 may allocate the memory amount of the memory 13 to the first deinterleaving unit 41 and the first delay unit 366 for the error correction unit 312, when operating in the tenth UL mode, the memory control unit 14 may allocate the memory amount of the memory 13 to the first deinterleaving unit 41 and the first delay unit 366 for the error correction unit 312, and when operating in the tenth LL mode, the memory control unit 14 may allocate the memory amount of the memory 13 to the second deinterleaving unit 51. Here, when at least a part of the memory amount required by the first delay unit 366 is L, the memory amount S of the memory 13 is Max(N+L,M). Furthermore, not only the first delay unit 366 but also a part of the memory amount required by the encoding unit 370 may be shared.

[0201] In this embodiment, the memory 13 has a tenth memory area and an eleventh memory area. The tenth memory area is used in the UL deinterleaving process, and the eleventh memory area is used in the LL deinterleaving process. One of the tenth memory area and the eleventh memory area is included in the other.

[0202] This makes it possible to reduce the amount of memory required in the deinterleaving process in the error correction step, as in the third embodiment and the like.

[0203] (Embodiment 6) A method for processing broadcast signals in the LDM system according to the sixth embodiment and a receiving device using the same will be described. The method for processing broadcast signals in the LDM system according to this embodiment differs from the method for processing broadcast signals in the LDM system according to the fifth embodiment in the calculation accuracy in the UL deinterleaving process. The method for processing broadcast signals in the LDM system and the receiving device according to this embodiment will be described below, focusing on the differences from the method for processing broadcast signals in the LDM system and the receiving device 410 according to the fifth embodiment.

[0204] A receiving device and a method for processing a broadcast signal of the LDM system according to this embodiment will be described with reference to Fig. 26. Fig. 26 is a block diagram showing a functional configuration of a receiving device 510 according to this embodiment.

[0205] As shown in FIG. 26, the receiving device 510 includes, as functional units, an ADC unit 11, a demodulation unit 20, a first separation unit 30, an error correction unit 512, a memory 13, a parameter determination unit 215, and a memory control unit 14.

[0206] The error correction unit 512 according to the present embodiment includes a first error correction unit 540 , a second error correction unit 250 , a first delay unit 366 , a third separation unit 360 , and an encoding unit 370 .

[0207] The first error correction unit 540 according to this embodiment has a first deinterleave unit 541 and a first decoding unit 44.

[0208] The error correction unit 512 according to the present embodiment has an eleventh mode and a twelfth mode as operation modes.

[0209] The operation mode is selected based on the result of the determination by the parameter determination unit 215. If the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are the same process, the error correction unit 512 operates in the eleventh mode. If the parameter determination unit 215 determines that the UL deinterleaving process and the LL deinterleaving process are not the same process, the error correction unit 512 operates in the twelfth mode.

[0210] In the eleventh mode, the first deinterleaving unit 541 performs UL deinterleaving. In this case, the memory control unit 14 allocates the memory amount required for the UL deinterleaving to the first deinterleaving unit 541. In this embodiment, the memory 13 has a twelfth memory area, a thirteenth memory area, and a fourteenth memory area. In the eleventh mode, the memory control unit 14 allocates the twelfth memory area of ​​the memory 13 to the first deinterleaving unit 541.

[0211] In the twelfth mode, the first deinterleaving unit 541 performs UL deinterleaving processing, and the second deinterleaving unit 51 performs LL deinterleaving processing. In this case, the memory control unit 14 allocates the memory amount required for the UL deinterleaving processing to the first deinterleaving unit 541, and allocates the memory amount required for the LL deinterleaving processing to the second deinterleaving unit 51. In this embodiment, in the twelfth mode, the memory control unit 14 allocates the thirteenth memory area of ​​the memory 13 to the first deinterleaving unit 541, and allocates the fourteenth memory area of ​​the memory 13 to the second deinterleaving unit 51.

[0212] Based on the judgment of the parameter judgment unit 215, when operating in the twelfth mode, the memory control unit 14 allocates the amount of memory required when the calculation processing bit length (bit width) of the data of the first deinterleaving unit 541 is BU2, and allocates the amount of memory required when the calculation processing bit length of the data of the second deinterleaving unit 51 is BL2, the first deinterleaving unit 541 performs UL deinterleaving processing, and the second deinterleaving unit 51 performs LL deinterleaving processing.

[0213] When operating in the eleventh mode based on the judgment of the parameter judgment unit 215, the memory control unit 14 allocates the memory amount required when the calculation processing bit length of the data of the first deinterleaving unit 541 is BU1. Here, BU1>BU2. That is, when operating in the eleventh mode, a larger memory amount is allocated to the first deinterleaving unit 541 than in the twelfth mode. Thus, in the error correction unit 512 according to this embodiment, when the LL deinterleaving process and the UL deinterleaving process are the same process, the bit length of the calculation data used in the UL deinterleaving process is longer than the bit length of the calculation data used in the UL deinterleaving process when the LL deinterleaving process and the UL deinterleaving process are not the same process.

[0214] For example, the arithmetic processing bit length of the first deinterleave unit 541 is BU1 and is common regardless of the operation mode, and when operating in the twelfth mode, the memory amount corresponding to the bit length of BU2 is assigned to the first deinterleave unit 541. Here, in the first deinterleave unit 541, by masking the arithmetic processing bit so that the arithmetic processing bit length becomes BU2, it is possible to perform the calculation with the bit precision of BU2 substantially. When the arithmetic processing bit length of the data of the first deinterleave unit 541 is BU1, the memory amount required is MU1, when the arithmetic processing bit length of the data of the first deinterleave unit 541 is BU2, the memory amount required is ML2, when the larger value of M and N is expressed as Max(M,N), the memory amount of the memory 13 is Max(MU1,MU2+ML2).

[0215] In other words, when the LL deinterleaving process and the UL deinterleaving process are the same process, the twelfth memory area is used in the UL deinterleaving process, and when the UL deinterleaving process and the LL deinterleaving process are not the same process, the thirteenth memory area is used in the UL deinterleaving process and the fourteenth memory area is used in the LL deinterleaving process, and the twelfth memory area is the thirteenth memory area plus at least a portion of the fourteenth memory area.

[0216] When the third separation unit 360 separates the UL signal component and the LL signal component, the power of the LL signal component is reduced according to the IL value, so if the bit length of the data of the first deinterleaving unit 541 is small, the quantization error for the LL signal becomes large, and the accuracy of the LL signal decreases. On the other hand, simply increasing the bit length of the data of the first deinterleaving unit 541 leads to an increase in the memory amount. Therefore, according to this embodiment, when the third deinterleaved LL signal separated by the third separation unit 360 is selected in the selection unit 255 in the eleventh mode, the memory amount allocated to the unused second deinterleaving unit 51 is reduced and the memory amount allocated to the first deinterleaving unit 541 is increased, thereby suppressing an increase in the total memory amount and improving the calculation accuracy of the first deinterleaving unit 541. Accordingly, the accuracy of the LL signal can be improved in the eleventh mode.

[0217] The memory used in the first delay unit 366 may also be subject to the control of the memory control unit 14. In the twelfth mode, the memory control unit 14 performs memory allocation with the bit length of the data of the first deinterleaving unit 541 as BU2, performs memory allocation with the bit length of the data of the second deinterleaving unit 51 as BL2, and does not perform memory allocation to the first delay unit 366. This is because, in the twelfth mode, the selection unit 255 selects the first deinterleaved LL signal which is the output signal of the second deinterleaving unit 51, and does not use the third deinterleaved LL signal which is the output signal of the third separation unit 360, so that memory allocation for delay processing in the first delay unit 366 is not required. When operating in the eleventh mode, the memory control unit 14 performs memory allocation with the bit length of the data of the first deinterleaving unit 541 as BU1, and allocates the amount of memory required for the first delay unit 366. Here, BU1>BU2. That is, in the eleventh mode, a larger amount of memory is allocated to the first deinterleave unit 541 and a larger amount of memory is allocated to the first delay unit 366 compared to the twelfth mode.

[0218] Here, the memory amount required when the calculation processing bit length of the data of the first deinterleaving unit 541 is BU1 is MU1, the memory amount required when the calculation processing bit length of the data of the first deinterleaving unit 541 is BU2 is MU2, the memory amount required when the calculation processing bit length of the data of the second deinterleaving unit 51 is BL2 is ML2, the memory amount required by the first delay unit 366 is D, and if the larger of M and N is expressed as Max(M,N), the memory amount of memory 13 is Max(MU1+D,MU2+ML2).

[0219] As a result, when the selection unit 255 selects the third deinterleaved LL signal which is the output signal of the third separation unit 360 in the eleventh mode, the memory allocation to the second deinterleaving unit 51 which outputs the unselected first deinterleaved LL signal is reduced, and the memory allocation to the first deinterleaving unit 541 is increased, while memory allocation is also performed to the first delay unit 366, thereby making it possible to improve the calculation accuracy of the first deinterleaving unit 541 while suppressing an increase in the total memory amount. Accordingly, it is possible to improve the accuracy of the LL signal in the eleventh mode.

[0220] (Embodiment 7) A description will be given of a method for processing broadcast signals in the LDM system according to embodiment 7, and a receiving device using the same. The method for processing broadcast signals in the LDM system according to this embodiment differs from the method for processing broadcast signals in the LDM system according to embodiment 1 mainly in the method for decoding LL signals.

[0221] In the first embodiment, successive interference cancellation (SIC) using hard decision is used as a method for decoding the LL signal, but in this embodiment, joint demodulation (JD) described in Non-Patent Document 1 is used as a method for decoding the LL signal. That is, in the first embodiment, the first demodulated LL signal is generated by the first separation unit 30, but in this embodiment, joint demodulation is performed without using the first separation unit 30.

[0222] The processing method for LDM-based broadcast signals and the receiving device according to the present embodiment will be described below, focusing on the differences from the processing method for LDM-based broadcast signals and the receiving device 10 according to the first embodiment.

[0223] The receiving device according to this embodiment will be described with reference to Fig. 27 and Fig. 28. Fig. 27 is a block diagram showing the functional configuration of a receiving device 610 according to this embodiment. Fig. 28 is a block diagram showing the functional configuration of a second decoding unit 654 according to this embodiment.

[0224] 27, the receiving device 610 includes, as functional units, an ADC unit 11, a demodulation unit 20, a memory 13, and a memory control unit 14, similarly to the receiving device 10 according to the first embodiment. The receiving device 610 according to the present embodiment further includes a UL amplitude correction unit 31 and an error correction unit 612.

[0225] The error correction unit 612 according to the present embodiment includes a first error correction unit 40 and a second error correction unit 650. The second error correction unit 650 according to the present embodiment includes a second deinterleave unit 51 and a second decoding unit 654. As shown in FIG. 28, the second decoding unit 654 according to the present embodiment includes a demapping unit 655, a bit DINT unit 56, an inner code decoding unit 57, and an outer code decoding unit 59.

[0226] The demapping unit 655 is a processing unit that performs demapping processing. In this embodiment, collective demodulation is performed in the demapping processing.

[0227] Hereinafter, the operation of the receiving device 610 using the method for processing LDM broadcast signals according to this embodiment will be described.

[0228] In this embodiment, the demodulated LDM signal demodulated by demodulation unit 20 is input to UL amplitude correction unit 31 and second deinterleaving unit 51 of second error correction unit 650 in error correction unit 612. UL amplitude correction unit 31 outputs the amplitude-corrected LDM signal to first error correction unit 40 in error correction unit 612, similar to UL amplitude correction unit 31 in the first embodiment.

[0229] The signal deinterleaved by the second deinterleaving unit 51 is input to a second decoding unit 654. As shown in Fig. 28, the second error correction unit 650 according to the present embodiment differs in the configuration of a demapping unit 655 from the configuration of the second error correction unit 50 according to the first embodiment.

[0230] Specifically, in the demapping unit 55 according to the first embodiment, the demapping process is performed based on the modulation method used in the LL signal, and the likelihood information for each modulated bit is calculated. On the other hand, in the demapping unit 655 according to the present embodiment, the demapping process is performed based on a mapping point where the UL signal and the LL signal are combined, that is, a mapping point calculated from the modulation method and IL value of each of the UL signal and the LL signal, and the likelihood information for each modulated bit is calculated and output to the bit DINT unit 56. For example, if the mapping point of the modulation method of the UL signal is the UM point and the mapping point of the modulation method of the LL signal is the LM point, the demapping unit 55 according to the first embodiment performs the demapping process at the mapping point of the LM point, whereas the demapping unit 655 performs the demapping process based on the mapping point of UL×LM point.

[0231] The receiving device 610 has a first mode and a second mode as operation modes of the error correction unit 612. In the first mode, error correction is performed in the first error correction unit 40, and in the second mode, error correction is performed in the second error correction unit 650. The memory control unit 14 allocates a memory area of ​​the memory 13 to the processing in the first error correction unit 40 in the first mode, and allocates a memory area of ​​the memory 13 to the processing in the second error correction unit 650 in the second mode.

[0232] The method of determining the operation mode is the same as the method of determining the operation mode in embodiment 1. According to this embodiment, the memory 13 can be shared by the first error correction unit 40 and the second error correction unit 650 in accordance with the user viewing either the UL signal broadcast or the LL signal broadcast. This makes it possible to reduce the amount of memory required for processing by the receiving device 610 using collective demodulation.

[0233] (Embodiment 8) A method for processing broadcast signals in the LDM system according to the eighth embodiment and a receiving device using the same will be described. The method for processing broadcast signals in the LDM system according to the present embodiment differs from the method for processing broadcast signals in the LDM system according to the second embodiment mainly in the method for decoding the LL signal.

[0234] In the second embodiment, successive interference cancellation using hard decision is used as a method for decoding the LL signal, but in the present embodiment, as in the seventh embodiment, the collective demodulation described in Non-Patent Document 1 is used as a method for decoding the LL signal. That is, in the second embodiment, the first demodulated LL signal is generated by the first separation unit 30, but in the present embodiment, the collective demodulation is performed without using the first separation unit 30.

[0235] Below, the LDM broadcast signal processing method and receiving device of this embodiment will be described, focusing on the differences between the LDM broadcast signal processing method and receiving device 110 of embodiment 2, and the LDM broadcast signal processing method and receiving device 610 of embodiment 7.

[0236] The receiving device according to this embodiment will be described with reference to Fig. 29. Fig. 29 is a block diagram showing the functional configuration of receiving device 710 according to this embodiment.

[0237] 29, the receiving device 710 includes, as functional units, an ADC unit 11, a demodulation unit 20, a memory 13, a memory control unit 14, and a parameter determination unit 115, similar to the receiving device 110 according to the second embodiment. The receiving device 710 according to the present embodiment further includes a UL amplitude correction unit 31 and an error correction unit 612, similar to the receiving device 610 according to the seventh embodiment.

[0238] Hereinafter, the operation of the receiving device 710 using the method for processing a broadcast signal of the LDM system according to the present embodiment will be described.

[0239] In this embodiment, the demodulated LDM signal demodulated by demodulation section 20 is input to UL amplitude correction section 31 and second deinterleave section 51 of second error correction section 650 in error correction section 612 .

[0240] The demapping unit 655 in the second decoding unit 654, like the demapping unit 655 in embodiment 7, performs demapping processing based on the mapping point where the UL signal and the LL signal are combined, i.e., the mapping point calculated from the modulation method and IL value of each of the UL signal and the LL signal, calculates likelihood information for each modulated bit, and outputs it to the bit DINT unit 56.

[0241] The error correction unit 612 of the receiving device 710 has a third mode and a fourth mode as operation modes, as in the second embodiment. When the parameter determination unit 115 determines that the UL parameter does not indicate the longest time interleaving length and that the LL parameter does not indicate the longest time interleaving length, the error correction unit 612 operates in the third mode. In the third mode, the error correction unit 612 performs both the UL deinterleaving process and the LL deinterleaving process. The memory control unit 14 assigns a memory area corresponding to the UL parameter to the first error correction unit 40, and assigns a memory area corresponding to the LL parameter to the second error correction unit 650. For example, the memory control unit 14 assigns a memory amount to the first error correction unit 40, the upper limit of which is the memory amount required when the UL parameter is (3), and assigns a memory amount to the second error correction unit 650, the upper limit of which is the memory amount required when the LL parameter is (3).

[0242] On the other hand, when the parameter determination unit 115 determines that at least one of the UL parameters and the LL parameters indicates the longest time interleaving length, the error correction unit 612 operates in the fourth mode. In the fourth mode, the error correction unit 612 performs UL deinterleaving processing or LL deinterleaving processing based on channel selection information not included in the LDM signal. In the fourth mode, the memory control unit 14 allocates a memory area to only one of the first error correction unit 40 and the second error correction unit 650. The memory amount to be allocated to either the first error correction unit 40 or the second error correction unit 650 is determined based on, for example, the channel selection information of the user. With the above configuration, the memory amount of the memory 13 can be reduced even when batch demodulation is used.

[0243] (Embodiment 9) A method for processing broadcast signals in the LDM system according to the ninth embodiment and a receiving device using the same will be described. The method for processing broadcast signals in the LDM system according to the present embodiment differs from the method for processing broadcast signals in the LDM system according to the third embodiment mainly in the method for decoding the LL signal.

[0244] In the third embodiment, successive interference cancellation using hard decision is used as a method for decoding the LL signal, but in the present embodiment, as in the seventh embodiment, the collective demodulation described in Non-Patent Document 1 is used as a method for decoding the LL signal. That is, in the third embodiment, the first demodulated LL signal is generated by the first separation unit 30, but in the present embodiment, the collective demodulation is performed without using the first separation unit 30.

[0245] Below, the LDM broadcast signal processing method and receiving device of this embodiment will be described, focusing on the differences between the LDM broadcast signal processing method and receiving device 210 of embodiment 3, and the LDM broadcast signal processing method and receiving device 610 of embodiment 7.

[0246] A receiving device according to this embodiment will be described with reference to Fig. 30. Fig. 30 is a block diagram showing a functional configuration of a receiving device 810 according to this embodiment.

[0247] 30, the receiving device 810 includes, as functional units, an ADC unit 11, a demodulation unit 20, a memory 13, a memory control unit 14, and a parameter determination unit 215, similarly to the receiving device 210 according to the third embodiment. The receiving device 810 according to the present embodiment further includes a UL amplitude correction unit 31 and an error correction unit 812.

[0248] The error correction unit 812 according to this embodiment has a first error correction unit 40 and a second error correction unit 850. The second error correction unit 850 according to this embodiment has a second deinterleaving unit 51, a selection unit 855, and a second decoding unit 654.

[0249] The selection unit 855 according to this embodiment is a processing unit that selects a signal to be input to the second decoding unit 654. The selection unit 855 selects one of the signal input from the second deinterleaving unit 51 and the signal input from the first deinterleaving unit 41 based on the determination result of the parameter determination unit 215, i.e., the operation mode, and inputs the selected signal to the second decoding unit 654.

[0250] Hereinafter, the operation of the receiving device 810 using the method for processing LDM broadcast signals according to this embodiment will be described.

[0251] In this embodiment, the demodulated LDM signal demodulated by demodulation section 20 is input to UL amplitude correction section 31 and second deinterleave section 51 of second error correction section 850 in error correction section 812 .

[0252] The demapping unit 655 in the second decoding unit 654, like the demapping unit 655 in embodiment 7, performs demapping processing based on the mapping point where the UL signal and the LL signal are combined, i.e., the mapping point calculated from the modulation method and IL value of each of the UL signal and the LL signal, calculates likelihood information for each modulated bit, and outputs it to the bit DINT unit 56.

[0253] The selection unit 855 selects one of the signal input from the second deinterleaving unit 51 and the signal input from the first deinterleaving unit 41 based on the result of the determination by the parameter determination unit 215, i.e., the operation mode, and inputs it to the second decoding unit 654. The determination method of the parameter determination unit 215 and the allocation of the memory 13 in the fifth operation mode and the sixth operation mode corresponding thereto are the same as those in the third embodiment. In this embodiment, when the selection unit 855 selects the output of the first deinterleaving unit 41, the UL amplitude correction for the UL signal has already been performed by the UL amplitude correction unit 31, so that the amplitude value of the mapping point of the UL×LM point in the demapping unit 655 is adjusted so as to cancel the correction by the UL amplitude correction unit 31. With the above configuration, the memory amount of the memory 13 can be reduced even when batch demodulation is used.

[0254] (Other embodiments) Although the processing method of the LDM broadcast signal according to the aspect of the present disclosure has been described based on the embodiment, the present disclosure is not limited to this embodiment. For example, the present disclosure may be realized by combining the components described in this specification in any way, or by excluding some of the components. In addition, the present disclosure also includes modifications obtained by applying various modifications that a person skilled in the art can think of to the above-mentioned embodiment without departing from the gist of the present disclosure, that is, the meaning of the words described in the claims.

[0255] For example, in the above embodiment, the input signal to the ADC unit 11 is an IF signal, but it may be a baseband signal. Also, the receiving device may further include an RF unit that converts an RF signal into a baseband signal.

[0256] In addition, in each embodiment, the LDM method is applied to ISDB-T described in Non-Patent Document 2 as a broadcasting method, but the present disclosure is not limited to this method. For example, the present disclosure can be applied to a method in which the LDM method is similarly implemented for a new broadcasting method having multiple time interleaving parameters, such as the method described in Non-Patent Document 2. The LDM method is a method for superimposing LL signals while maintaining the structure of the OFDM frame, as in the method described in Non-Patent Document 1, and it is sufficient that frequency interleaving and time interleaving can be set independently for UL signals and LL signals. In that case, the demodulation process in the demodulation unit and the error correction process in the error correction unit can be changed to the error correction of the corresponding broadcasting method.

[0257] In the first to sixth embodiments, the first separation unit 30 includes the UL amplitude correction unit 31, but the amplitude of the UL signal may not be adjusted by the UL amplitude correction unit 31, and may be adjusted in a separate process. That is, the UL amplitude correction unit 31 may be omitted in the first separation unit 30, and the first hard decision unit 32 may perform hard decision based on mapping points of UL amplitude values ​​that have not been UL amplitude corrected, and the demapping unit 45 of the first error correction unit 40 may perform mapping processing based on mapping points of UL amplitude values ​​that have not been UL amplitude corrected. Similarly, the second hard decision unit 262 of the second separation unit 260 may perform hard decision based on mapping points of amplitude values ​​that have not been UL amplitude corrected.

[0258] The following forms may also be included within the scope of one or more aspects of the present disclosure.

[0259] (1) Some of the components constituting the above-mentioned receiving device may be a computer system composed of a microprocessor, ROM, RAM, a hard disk unit, a display unit, a keyboard, a mouse, etc. A computer program is stored in the RAM or hard disk unit. The microprocessor operates according to the computer program to achieve its functions. Here, the computer program is composed of a combination of multiple instruction codes that indicate commands for a computer to achieve a specified function.

[0260] (2) Some of the components constituting the above-mentioned receiving device may be composed of one system LSI (Large Scale Integration). The system LSI is an ultra-multifunctional LSI manufactured by integrating multiple components on one chip, and specifically, is a computer system including a microprocessor, ROM, RAM, etc. A computer program is stored in the RAM. The system LSI achieves its functions by the microprocessor operating in accordance with the computer program.

[0261] (3) Some of the components constituting the above-mentioned receiving device may be composed of an IC card or a standalone module that is detachable from each device. The IC card or the module is a computer system composed of a microprocessor, ROM, RAM, etc. The IC card or the module may include the above-mentioned ultra-multifunction LSI. The microprocessor operates according to a computer program, causing the IC card or the module to achieve its functions. The IC card or the module may be tamper-resistant.

[0262] (4) Furthermore, some of the components constituting the above-mentioned receiving device may be the computer program or the digital signal recorded on a computer-readable recording medium, such as a flexible disk, a hard disk, a CD-ROM, an MO, a DVD, a DVD-ROM, a DVD-RAM, a BD (Blu-ray (registered trademark) Disc), a semiconductor memory, etc. Also, some of the components constituting the above-mentioned receiving device may be the digital signal recorded on such a recording medium.

[0263] In addition, some of the components constituting the above-mentioned receiving device may transmit the computer program or the digital signal via a telecommunications line, a wireless or wired communication line, a network such as the Internet, data broadcasting, etc.

[0264] (5) The present disclosure may be embodied as any of the methods described above, a computer program for implementing these methods by a computer, or a digital signal comprising the computer program.

[0265] (6) The present disclosure may also provide a computer system having a microprocessor and a memory, the memory storing the computer program, and the microprocessor operating in accordance with the computer program.

[0266] (7) The program or the digital signal may also be implemented by another independent computer system by recording it on a recording medium and transferring it, or by transferring the program or the digital signal via a network, etc.

[0267] (8) The above-described embodiments and modifications may be combined with each other. [Industrial Applicability]

[0268] The LDM broadcast signal processing method and the like disclosed herein can be used, for example, in a receiving device that receives a digital broadcast signal. [Explanation of symbols]

[0269] 10, 110, 210, 310, 310a, 410, 510, 610, 710, 810 Receiving device 11 ADC section 12, 212, 312, 312a, 512, 612, 812 Error correction unit 13. Memory 14 Memory control section 20 Demodulation section 21 Time axis processing section 22 FFT section 23 Transmission line characteristic estimation unit 24 Equalization section 25 TMCC / AC Decoding Section 30 First separation section 31 UL amplitude correction section 32 First Hard Judgment Department 33 First removal section 34 First LL amplitude correction section 40, 540 First Error Correction Unit 41, 541 First deinterleave unit 42, 52 Frequency DINT section 43, 53 Time DINT section 44 First Decoding Unit 45, 55, 655 Demap section 46, 56 bit DINT section 47, 57 Inner code decoding section 48 byte DINT section 49, 59 Outer code decoding section 50, 250, 250a, 650, 850 Second error correction unit 51 Second deinterleave unit 54, 654 Second Decoding Unit 115, 215 Parameter determination section 255, 855 selection section 260 Second separation section 262 Second hard judgment section 263 Second removal section 264 Second LL amplitude correction section 356 Second Delay Division 360 Third separation section 363 Third removal section 364 Third LL amplitude correction section 366 First Delay Division 370 Encoding section 371 Outer code encoder 372 byte INT part 373 Inner code encoder 374-bit INT section 375 Mapping Department

Claims

1. A method for processing a broadcast signal of a Layered Division Multiplexing (LDM) system, in which an UL (Upper Layer) signal, which is a broadcast signal of a first system, and an LL (Lower Layer) signal, which is a broadcast signal of a second system having a power level lower than that of the UL signal, are multiplexed on one physical channel, a demodulation step of demodulating an LDM signal which is a broadcast signal of the LDM system; a first separation step of separating a first demodulated LL signal as a demodulated LL signal which is the LL signal demodulated in the demodulation step from a demodulated LDM signal which is the LDM signal demodulated in the demodulation step; an error correction step of performing error correction on at least one of the demodulated LDM signal and a signal related to the LL signal demodulated in the demodulation step; The error correction step includes at least one of a first deinterleaving step and a second deinterleaving step, and at least one of a first decoding step and a second decoding step; In the first deinterleaving step, a UL deinterleaving process is performed on a demodulated UL signal related to the UL signal among the demodulated LDM signals; In the second deinterleaving step, an LL deinterleaving process is performed on the first demodulated LL signal; In the first decoding step, a deinterleaved LDM signal, which is the demodulated LDM signal that has been subjected to the UL deinterleaving process, is decoded; In the second decoding step, the deinterleaved demodulated LL signal is decoded; The first separation step comprises: a UL amplitude correction step of performing amplitude correction on the demodulated LDM signal; a first hard decision step of performing a hard decision on the amplitude-corrected LDM signal, which is the demodulated LDM signal whose amplitude has been corrected, at a code point determined by the format of the UL signal; a first difference step of subtracting the amplitude corrected LDM signal on which the hard decision has been performed from the amplitude corrected LDM signal; a first LL amplitude correction step of performing amplitude correction on a first difference signal obtained in the first difference step to generate the first demodulated LL signal. A method for processing LDM broadcast signals.

2. the error correction step has a first mode and a second mode as operation modes, In the first mode, the first decoding step is performed, In the second mode, the second decoding step is performed.

2. A method for processing an LDM broadcast signal according to claim 1.

3. The first mode or the second mode is selected based on information other than information transmitted using the LDM signal.

3. A method for processing an LDM broadcast signal according to claim 2.

4. In the error correction step, a memory is used for storing temporary data, the memory has a first memory area and a second memory area; The first memory area is used in the first deinterleaving step and the first decoding step; The second memory area is used in the second deinterleaving step and the second decoding step; One of the first memory area and the second memory area is contained within the other.

3. A method for processing an LDM broadcast signal according to claim 2.

5. In the error correction step, a memory is used for storing temporary data; The memory includes: A third memory area; a fourth memory area that does not overlap with the third memory area; a fifth memory area that does not overlap with the third memory area; the UL signal includes 13 segments; The 13 segments include a 1-segment portion that is one segment and 12 segment portions other than the 1-segment portion, The third memory area is used in the processing for the one segment portion in the first deinterleaving step and the first decoding step, the fourth memory area is used in the processing for the twelve segment portions, and the fifth memory area is used in the second deinterleaving step and the second decoding step; one of the fourth memory area and the fifth memory area is included in the other, In the first mode, error correction is performed on the 1-segment portion and the 12-segment portion using the third memory area and the fourth memory area; In the second mode, the third memory area and the fifth memory area are used to perform error correction on the one segment portion and the demodulated LL signal.

3. A method for processing an LDM broadcast signal according to claim 2.

6. the LDM signal includes an UL parameter indicating a time interleaving length of the UL signal and an LL parameter indicating a time interleaving length of the LL signal; If the UL parameters do not indicate a maximum time interleaving length and the LL parameters do not indicate a maximum time interleaving length, then in the error correction step, both the UL deinterleaving process and the LL deinterleaving process are performed.

2. A method for processing an LDM broadcast signal according to claim 1.

7. the LDM signal includes an UL parameter indicating a time interleaving length of the UL signal and an LL parameter indicating a time interleaving length of the LL signal; When at least one of the UL parameters and the LL parameters indicates the longest time interleaving length, the UL deinterleaving process or the LL deinterleaving process is performed in the error correction step based on channel selection information not included in the LDM signal.

2. A method for processing an LDM broadcast signal according to claim 1.

8. In the error correction step, a memory is used for storing temporary data; the memory has a sixth memory area and a seventh memory area; In the UL deinterleaving process, the sixth memory area is used, In the LL deinterleaving process, the seventh memory area is used, One of the sixth memory area and the seventh memory area is included in the other. A method for processing an LDM broadcast signal according to claim 7.

9. When the UL deinterleaving process and the LL deinterleaving process are the same process, the error correction step includes a second separation step of extracting a second deinterleaved LL signal from the deinterleaved LDM signal as the deinterleaved demodulated LL signal; The second separation step comprises: a second hard decision step of performing the hard decision on the deinterleaved LDM signal; a second difference step of subtracting the deinterleaved LDM signal on which the hard decision has been performed from the deinterleaved LDM signal; a second LL amplitude correction step of performing amplitude correction on the second difference signal obtained in the second difference step to generate the second deinterleaved LL signal; the error correction step includes the second decoding step, In the second decoding step, the second deinterleaved LL signal is decoded as the deinterleaved demodulated LL signal.

2. A method for processing an LDM broadcast signal according to claim 1.

10. The error correction step includes the first decoding step.

10. A method for processing an LDM broadcast signal according to claim 9.

11. When the hierarchical structure of the UL signal and the hierarchical structure of the LL signal are the same, and the time interleaving length of the UL signal and the time interleaving length of the LL signal are the same, it is determined that the UL deinterleaving process and the LL deinterleaving process are the same process.

10. A method for processing an LDM broadcast signal according to claim 9.

12. In the error correction step, a memory is used for storing temporary data; the memory has an eighth memory area and a ninth memory area; In the UL deinterleaving process, the eighth memory area is used, In the LL deinterleaving process, the ninth memory area is used, One of the eighth memory area and the ninth memory area is included in the other.

10. A method for processing an LDM broadcast signal according to claim 9.

13. When the UL deinterleaving process and the LL deinterleaving process are the same process, The error correction step includes: a re-encoding step of encoding a decoded UL signal obtained by decoding the deinterleaved LDM signal in the first decoding step; and a third separation step of extracting a third deinterleaved LL signal from the deinterleaved LDM signal as the deinterleaved demodulated LL signal; The third separation step comprises: a third difference step of subtracting a re-encoded UL signal that has been encoded in the re-encoding step from the deinterleaved LDM signal; a third LL amplitude correction step of performing amplitude correction on the third difference signal obtained in the third difference step to generate a third deinterleaved LL signal; the error correction step includes the second decoding step, In the second decoding step, the third deinterleaved LL signal is decoded as the deinterleaved demodulated LL signal.

2. A method for processing an LDM broadcast signal according to claim 1.

14. In the error correction step, a memory is used for storing temporary data; the memory has a tenth memory area and an eleventh memory area; In the UL deinterleaving process, the tenth memory area is used, In the LL deinterleaving process, the eleventh memory area is used, One of the tenth memory area and the eleventh memory area is included in the other. A method for processing an LDM broadcast signal according to claim 13.

15. When the LL deinterleaving process and the UL deinterleaving process are the same process, the bit length of the calculation data used in the UL deinterleaving process is longer than the bit length of the calculation data used in the UL deinterleaving process when the LL deinterleaving process and the UL deinterleaving process are not the same process. A method for processing an LDM broadcast signal according to claim 13.

16. In the error correction step, a memory is used for storing temporary data; the memory has a twelfth memory area, a thirteenth memory area, and a fourteenth memory area; When the LL deinterleaving process and the UL deinterleaving process are the same process, the twelfth memory area is used in the UL deinterleaving process; When the UL deinterleaving process and the LL deinterleaving process are not the same process, the thirteenth memory area is used in the UL deinterleaving process; The fourteenth memory area is used in the LL deinterleaving process; The twelfth memory area is a memory area obtained by adding at least a part of the fourteenth memory area to the thirteenth memory area. A method for processing an LDM broadcast signal according to claim 15.

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