Apparatus and method for generating broadcast signal frame

Abstract

An apparatus and method for generating broadcast signal frames are disclosed. An apparatus for generating broadcast signal frames according to an embodiment of the present invention includes: a combiner configured to generate a multiplexed signal by combining core layer signals and enhancement layer signals; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving applied to both the core layer signal and the enhancement layer signal; and a frame builder configured to generate a broadcast signal frame, wherein the broadcast signal frame includes a preamble for signaling time interleaver information corresponding to the time interleaver, wherein the preamble includes a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channels.

Description

[0001] This application is a divisional application of the invention patent application filed on September 8, 2017, with application number "201780056062.6" and titled "Apparatus for generating a broadcast signal frame including a preamble indicating the start position of the first complete FEC block and a method for generating a broadcast signal frame". Technical Field

[0002] This invention relates to broadcast signal transmission / reception technology used in broadcast systems, and more specifically, to broadcast signal transmission / reception systems in which two or more signals are multiplexed / demultiplexed and then transmitted / received. Background Technology

[0003] Bit-interleaved coded modulation (BICM) is a bandwidth-efficient transmission technique that is implemented by combining error-correcting encoders, bit-by-bit interleavers, and higher-order modulators.

[0004] Because BICM uses a low-density parity-check (LDPC) encoder or a turbo encoder as its error correction encoder, it can deliver excellent performance with a simple architecture. Furthermore, BICM offers advanced flexibility because the modulation order, error correction code length, and code rate can be selected in various ways. Due to these advantages, BICM has been adopted in broadcast standards such as DVB-T2 and DVB-NGH, and has a high probability of being used in other next-generation broadcast systems.

[0005] To support multiple services simultaneously, multiplexing is required, that is, the processing of multiple signals. Among multiplexing techniques, widely used technologies currently include Time Division Multiplexing (TDM), which is suitable for dividing and using time resources, and Frequency Division Multiplexing (FDM), which is suitable for dividing and using frequency resources. In other words, TDM is a method of allocating time periods to various services, while FDM is a technique of allocating frequency resource segments to various services and then using them. Recently, there has been an urgent need for a new multiplexing technology suitable for next-generation broadcast systems, offering greater flexibility and performance than TDM and FDM. Summary of the Invention

[0006] Technical issues

[0007] One object of the present invention is to provide a broadcast signal frame structure, wherein the broadcast signal frame structure applies a new signal multiplexing technique that can provide greater flexibility and performance than TDM and FDM.

[0008] Furthermore, one object of the present invention is to efficiently perform signaling operations related to time interleaving, especially when using convolutional time interleaving.

[0009] Furthermore, one object of the present invention is to efficiently transmit a field indicating the start position of the first complete FEC block of the physical layer channel in a subframe.

[0010] Technical solution

[0011] To achieve the above objectives, the present invention provides an apparatus for generating broadcast signal frames, comprising: a combiner configured to generate a multiplexed signal by combining core layer signals and enhancement layer signals; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving applied to both the core layer signal and the enhancement layer signal; and a frame builder configured to generate broadcast signal frames, wherein the broadcast signal frames include a preamble for signaling time interleaver information corresponding to the time interleaver. In this case, the preamble includes a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channels.

[0012] In this case, the start position of the first complete FEC block can be specified relative to the first unit of each physical layer channel in the physical layer channel.

[0013] In this case, when the operating mode of the time interleaver is a mode corresponding to convolutional time interleaver, the start position of the first complete FEC block can indicate the first unit of the first complete FEC block before convolutional time interleaver, and the position of the first unit of the first complete FEC block can be signaled after convolutional time interleaver.

[0014] In this case, the field indicating the start position of the first complete FEC block can correspond to the position after convolutional temporal interleaving, wherein the position after convolutional temporal interleaving is calculated by adding the position (C) before convolutional temporal interleaving and the delay caused by convolutional temporal interleaving.

[0015] In this case, the latency caused by convolutional temporal interleaving can be calculated by using the position (L1D_plp_CTI_start_row) of the interleaving selector corresponding to the convolutional temporal interleaving.

[0016] In this case, the delay caused by convolutional temporal interleaving can be calculated by using the modulo operation of the sum of the position of the interleaver selector corresponding to convolutional temporal interleaving and the position before convolutional temporal interleaving (L1D_plp_CTI_start_row+C) and the number of delay lines (N_row) corresponding to convolutional temporal interleaving.

[0017] In this case, the location of the signal transmission interleaver selector can be used only for the core layer physical layer channel corresponding to the core layer, and the location of the signal transmission interleaver selector can be omitted for the enhancement layer physical layer channel corresponding to the enhancement layer.

[0018] In this case, the position of the interleaver selector for the enhancement layer physical layer channel can be calculated by using the position of the interleaver selector that is signaled for the core layer physical layer channel corresponding to the enhancement layer physical layer channel.

[0019] In this case, the field indicating the start position of the first complete FEC block can be 22 bits long.

[0020] In this case, a field indicating the start position of the first complete FEC block can be sent by signaling for each of the core layer physical layer channel and the enhancement layer physical layer channel.

[0021] Furthermore, embodiments of the present invention provide a method for generating a broadcast signal frame, comprising: generating a multiplexed signal by combining a core layer signal and an enhancement layer signal; reducing the power of the multiplexed signal to a power level corresponding to the core layer signal; generating a time-interleaved signal by performing interleaving applied to both the core layer signal and the enhancement layer signal; and generating a broadcast signal frame, wherein the broadcast signal frame includes a preamble for signaling time-interleaved information corresponding to the interleaving. In this case, the preamble includes a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channels.

[0022] In this case, the start position of the first complete FEC block can be specified relative to the first unit of each physical layer channel in the physical layer channel.

[0023] In this case, when the interleaving corresponds to convolutional time interleaving, the start position of the first complete FEC block can indicate the first cell of the first complete FEC block before convolutional time interleaving, and the position of the first cell of the first complete FEC block can be signaled after convolutional time interleaving.

[0024] In this case, the field indicating the start position of the first complete FEC block can correspond to the position after convolutional time interleaving, wherein the position after convolutional time interleaving is calculated by adding the position (C) before convolutional time interleaving and the delay caused by convolutional time interleaving.

[0025] In this case, the latency caused by convolutional temporal interleaving can be calculated by using the position (L1D_plp_CTI_start_row) of the interleaving selector corresponding to the convolutional temporal interleaving.

[0026] In this case, the delay caused by convolutional temporal interleaving can be calculated by using the modulo operation of the sum of the position of the interleaver selector corresponding to convolutional temporal interleaving and the position before convolutional temporal interleaving (L1D_plp_CTI_start_row+C) and the number of delay lines (N_row) corresponding to convolutional temporal interleaving.

[0027] In this case, the location of the signal transmission interleaver selector can be used only for the core layer physical layer channel corresponding to the core layer, and the location of the signal transmission interleaver selector can be omitted for the enhancement layer physical layer channel corresponding to the enhancement layer.

[0028] In this case, the position of the interleaver selector for the enhancement layer physical layer channel can be calculated by using the position of the interleaver selector that is signaled for the core layer physical layer channel corresponding to the enhancement layer physical layer channel.

[0029] In this case, the field indicating the start position of the first complete FEC block can be 22 bits long.

[0030] In this case, a field indicating the start position of the first complete FEC block can be sent by signaling for each of the core layer physical layer channel and the enhancement layer physical layer channel.

[0031] Beneficial effects

[0032] According to the present invention, a frame structure is provided, wherein the frame structure provides a new signal multiplexing technique that can provide greater flexibility and performance than TDM and FDM.

[0033] Furthermore, according to the present invention, signal transmission operations related to time interleaving can be performed efficiently, particularly when using convolutional time interleaving.

[0034] Furthermore, according to the present invention, a field indicating the start position of the first complete FEC block of the physical layer channel in the subframe can be effectively transmitted by signal. Attached Figure Description

[0035] Figure 1 This is a block diagram illustrating a broadcast signal transmission / reception system according to an embodiment of the present invention;

[0036] Figure 2 This is an operation flowchart illustrating a broadcast signal transmission / reception method according to an embodiment of the present invention;

[0037] Figure 3 It is shown Figure 1 A block diagram of an example of a device for generating broadcast signal frames;

[0038] Figure 4 This is a diagram illustrating an example of the structure of a broadcast signal frame;

[0039] Figure 5 It is shown Figure 4 A diagram illustrating an example of receiving and processing a broadcast signal frame;

[0040] Figure 6 It is shown Figure 4 A diagram illustrating yet another example of the reception processing of the broadcast signal frame shown;

[0041] Figure 7 It is shown Figure 1 A block diagram of yet another example of a device for generating broadcast signal frames;

[0042] Figure 8 It is shown Figure 1 A block diagram of an example signal demultiplexer shown;

[0043] Figure 9 It is shown Figure 8 A block diagram illustrating an example of a core layer BICM decoder and an enhancement layer symbol extractor;

[0044] Figure 10 It is shown Figure 8 A block diagram of yet another example of the core layer BICM decoder and enhancement layer symbol extractor shown;

[0045] Figure 11 It is shown Figure 8 A block diagram of yet another example of the core layer BICM decoder and enhancement layer symbol extractor shown;

[0046] Figure 12 It is shown Figure 1 A block diagram of yet another example of a signal demultiplexer shown;

[0047] Figure 13 This is a diagram illustrating the power increase attributed to the combination of core layer signals and enhancement layer signals;

[0048] Figure 14 This is an operation flowchart illustrating a method for generating broadcast signal frames according to an embodiment of the present invention;

[0049] Figure 15 This is a diagram illustrating the structure of a superframe including broadcast signal frames according to an embodiment of the present invention;

[0050] Figure 16 This is a diagram illustrating an example of an LDM frame that includes multiple physical layer channels and uses a two-layer LDM.

[0051] Figure 17 This is a diagram illustrating yet another example of an LDM frame that includes multiple physical layer channels and uses a two-layer LDM.

[0052] Figure 18 This is a diagram illustrating an application example of an LDM frame using multiple physical layer channels and a two-layer LDM;

[0053] Figure 19 This is a diagram illustrating yet another application example of an LDM frame using multiple physical layer channels and two layers of LDM;

[0054] Figure 20 This is a diagram illustrating an example of using a convolutional temporal interleaver;

[0055] Figure 21 This is a diagram illustrating yet another example of using a convolutional temporal interleaver;

[0056] Figure 22 This is a diagram illustrating an example of using a hybrid time interleaver;

[0057] Figure 23 It is shown Figure 22 A diagram illustrating time interleaver grouping in the example;

[0058] Figures 24 to 26 This shows the calculation Figure 23 A diagram illustrating the handling of incomplete FEC block sizes in the example;

[0059] Figure 27 This is a diagram used to explain the number of bits required for L1D_plp_fec_block_start when L1D_plp_TI_mode = "00";

[0060] Figure 28 and Figure 29 This is a diagram used to explain the number of bits required for L1D_plp_CTI_fec_block_start when L1D_plp_TI_mode = "01";

[0061] Figure 30 This is a diagram showing an example of L1D_plp_fec_block_start for the enhancement layer;

[0062] Figure 31 This is a diagram illustrating the relationship between convolutional temporal interleaving before and after convolutional temporal interleaving;

[0063] Figure 32This is a diagram illustrating the case of a single physical layer channel with convolutional temporal interleaving applied at depth 0;

[0064] Figure 33 This is a diagram illustrating receiver-side operation in the case of a single physical layer channel; and

[0065] Figure 34 and 35 This is a diagram showing the situation of multiple enhanced physical layer channels. Detailed Implementation

[0066] The present invention will now be described in detail with reference to the accompanying drawings. In this specification, redundant descriptions that would unnecessarily obscure the essential points of the invention, as well as descriptions of well-known functions and configurations, will be omitted. Embodiments of the invention are provided to fully describe the invention to those skilled in the art. Therefore, the shapes, dimensions, etc., of components in the drawings may be exaggerated to make the description clear.

[0067] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0068] Figure 1 This is a block diagram illustrating a broadcast signal transmission / reception system according to an embodiment of the present invention.

[0069] refer to Figure 1 According to an embodiment of the present invention, a broadcast signal transmission / reception system includes a broadcast signal transmission device 110, a wireless channel 120, and a broadcast signal receiving device 130.

[0070] The broadcast signal transmitting apparatus 110 includes a means 111 for generating broadcast signal frames and an OFDM transmitter 113, wherein the means 111 for generating broadcast signal frames generates broadcast signal frames by multiplexing core layer data and enhancement layer data.

[0071] Apparatus 111 combines core layer signals corresponding to core layer data and enhancement layer signals corresponding to enhancement layer data with different power level combinations, and generates a multiplexed signal by performing interleaving on both the core layer signals and enhancement layer signals. In this case, apparatus 111 can use time-interleaved signals to generate broadcast signal frames including bootstrap and preamble. In this case, the broadcast signal frame can be an ATSC 3.0 frame.

[0072] In this scenario, time interleaving can utilize one of the time interleaving groups, and the boundary between time interleaving groups can be the boundary between the physical layer channels (PLPs) of the core layer corresponding to the core layer signal. In other words, one of the boundaries between the physical layer channels of the core layer can be the boundary between time interleaving groups.

[0073] OFDM transmitter 113 transmits multiplexed signals via antenna 117 using OFDM communication methods, thereby allowing the transmitted OFDM signals to be received on wireless channel 120 via antenna 137 of broadcast signal receiving device 130.

[0074] The broadcast signal receiving device 130 includes an OFDM receiver 133 and a signal demultiplexer 131. When a signal transmitted on the wireless channel 120 is received via antenna 137, the OFDM receiver 133 receives the OFDM signal through synchronization, channel estimation, and equalization.

[0075] In this case, OFDM receiver 133 can detect and demodulate the preamble from the OFDM signal, use the information included in the preamble to demodulate the preamble, and use the information included in the preamble to demodulate the superimposed payload.

[0076] The signal demultiplexer 131 first recovers the core layer data from the signal (superimposed payload) received via the OFDM receiver 133, and then recovers the enhancement layer data through cancellation corresponding to the recovered core layer data. In this case, the signal demultiplexer 131 may first generate a broadcast signal frame, recover the preamble, recover the preamble using information included in the preamble, and recover the data signal using signaling information included in the preamble. In this case, the signaling information may be L1 signaling information and may include injection level information, normalization factor information, etc.

[0077] In this case, the preamble may include PLP identification information for identifying the physical layer channel (PLP); and layer identification information for identifying the layer corresponding to the layer.

[0078] In this case, PLP identification information and layer identification information can be included in the preamble as distinct fields.

[0079] In this case, time interleaver information can be included in the preamble based on the core layer.

[0080] In this case, based on the comparison between the layer identification information and the predetermined value, the preamble can selectively include injection level information corresponding to the injection level controller for each physical layer channel (PLP).

[0081] In this case, the preamble can include physical layer channel type information, start position information, and size information.

[0082] In this case, type information can be used to identify one of the first type corresponding to non-distributed physical layer channels and the second type corresponding to distributed physical layer channels.

[0083] In this case, non-distributed physical layer channels can be assigned to continuous data unit indexes, and distributed physical layer channels can include two or more subslices.

[0084] In this case, for each physical layer channel (PLP), type information can be selectively transmitted by signal based on the comparison result between the layer identification information and a predetermined value.

[0085] In this case, type information can be sent via signals only to the core layer.

[0086] In this case, the starting position information can be the same as the index of the first data unit corresponding to the physical layer channel.

[0087] In this case, the start location information can be indicated by the cell addressing scheme to indicate the start location of the physical layer channel.

[0088] In this case, the start position information can be included in the preamble for each physical layer channel (PLP) without checking the conditional statement corresponding to the layer identification information.

[0089] In this case, size information can be generated based on the number of data units allocated to the physical layer channel.

[0090] In this case, size information can be included in the preamble used for each physical layer channel (PLP) without checking the conditions of the conditional statement corresponding to the layer identification information.

[0091] In this case, time-interleaved information can be sent using signals based on the core layer.

[0092] In this case, the time interleaver can correspond to a hybrid time interleaver. In this case, the physical layer channels (PLPs) of the core layer and enhancement layer can consist of only complete FEC blocks.

[0093] In this case, where the boundary between time-interleaved packets does not correspond to the boundary between FEC blocks in the enhancement layer, a preamble can be used to signal information for identifying a portion of an FEC block in the enhancement layer, where the FEC block corresponds to the boundary between time-interleaved packets.

[0094] In this case, the information used to identify a portion of the FEC block may include at least one of the following: the start position information of the physical layer channel (PLP) in the core layer, the start position information of the physical layer channel (PLP) in the enhancement layer, the modulation information corresponding to the enhancement layer, and the FEC type information corresponding to the enhancement layer.

[0095] In this case, the start position information of the physical layer channel (PLP) can correspond to the index of the first data unit of the physical layer channel (PLP).

[0096] In this case, modulation information can only be sent using a signal if the FEC type information meets the predetermined conditions.

[0097] In this case, the enhancement layer signal can correspond to enhancement layer data, wherein the enhancement layer data is recovered based on the elimination corresponding to the recovery of the core layer data, which corresponds to the core layer signal.

[0098] In this case, the temporal interleaver can correspond to the convolutional temporal interleaver, and the temporal interleaver group can include a physical layer channel (PLP), wherein the physical layer channel (PLP) includes incomplete FEC blocks, and the preamble can be used to signal the start position information of the first complete FEC block in the physical layer channel (PLP).

[0099] In this case, the time interleaver can perform interleaving by using one of several operating modes.

[0100] In this case, the operating modes may include a first mode corresponding to no temporal interleaving, a second mode for performing convolutional temporal interleaving, and a third mode for performing mixed temporal interleaving.

[0101] In this scenario, the preamble may include a field indicating the start position of the first complete FEC block for the first and second modes corresponding to the current physical layer channel, but may not include a field indicating the start position of the first FEC block for the third mode. In this case, the field indicating the start position may indicate the start position of the first FEC block that begins in the current physical layer channel during the current subframe.

[0102] In this case, the field indicating the start position of the first FEC block can be one of the first field used in the first mode and the second field used in the second mode, and the first field and the second field can have different lengths.

[0103] In this case, the length of the second field can be longer than the length of the first field.

[0104] In this case, the length of the first field can be determined based on the length of the LDPC codeword and the modulation order, and the length of the second field can be determined not only by the length of the LDPC codeword and the modulation order but also by further considering the depth of the convolutional time interleaver.

[0105] In this case, the length of the first field can be 15 bits, and the length of the second field can be 22 bits.

[0106] In this case, for each of the core layer corresponding to the core layer signal and the enhancement layer corresponding to the enhancement layer signal, the first field and the second field can be sent by signal respectively.

[0107] In this case, the preamble may include a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channel.

[0108] In this case, the start position of the first complete FEC block can be specified relative to the first unit of each physical layer channel in the physical layer channel.

[0109] In this case, when the operating mode of the time interleaver is the mode corresponding to convolutional time interleaver, the start position of the first complete FEC block can indicate the position of the first cell of the first complete FEC block before convolutional time interleaver, and the position of the first cell of the first complete FEC block can be signaled after convolutional time interleaver.

[0110] In this case, the field indicating the start position of the first complete FEC block can correspond to the position after convolutional temporal interleaving, where the position after convolutional temporal interleaving is calculated by adding the position (C) before convolutional temporal interleaving and the delay caused by convolutional temporal interleaving.

[0111] In this case, the latency caused by convolutional temporal interleaving can be calculated by using the position (L1D_plp_CTI_start_row) of the interleaving selector corresponding to the convolutional temporal interleaving.

[0112] In this case, the delay caused by convolutional temporal interleaving can be calculated by using the modulo operation of the sum of the position of the interleaver selector corresponding to convolutional temporal interleaving and the position before convolutional temporal interleaving (L1D_plp_CTI_start_row+C) and the number of delay lines (N_row) corresponding to convolutional temporal interleaving.

[0113] In this case, the location of the signal transmission interleaver selector can be used only for the core layer physical layer channel corresponding to the core layer, and the location of the signal transmission interleaver selector can be omitted for the enhancement layer physical layer channel corresponding to the enhancement layer.

[0114] In this case, the position of the interleaver selector for the enhancement layer physical layer channel can be calculated by using the position of the interleaver selector that is signaled for the core layer physical layer channel corresponding to the enhancement layer physical layer channel.

[0115] In this case, the field indicating the start position of the first complete FEC block can be 22 bits long.

[0116] In this case, a field indicating the start position of the first complete FEC block can be sent by signaling for each of the core layer physical layer channel and the enhancement layer physical layer channel.

[0117] As will be described in detail later, Figure 1 The apparatus 111 shown may include: a combiner configured to generate a multiplexed signal by combining core layer signals and enhancement layer signals; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving applied to both the core layer signal and the enhancement layer signal; and a frame builder configured to generate a broadcast signal frame, wherein the broadcast signal frame includes a preamble for signaling time interleaver information corresponding to the time interleaver. In this case, the combiner may combine the core layer signal and enhancement layer signal at different power levels. In this case, the preamble may include a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channel. Figure 1 The broadcast signal transmitting apparatus 110 shown can be considered to include: a combiner configured to generate a multiplexed signal by combining core layer signals and enhancement layer signals; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving applied to both the core layer signal and the enhancement layer signal; a frame builder configured to generate a broadcast signal frame, wherein the broadcast signal frame includes a preamble for signaling time interleaver information corresponding to the time interleaver; and an OFDM transmitter configured to transmit the broadcast signal frame via an antenna using an OFDM communication scheme. In this case, the combiner can combine the core layer signal and enhancement layer signal at different power levels. In this case, the preamble may include a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channels.

[0118] As will be described in detail later, Figure 1The signal demultiplexer shown may include: a time deinterleaving unit configured to generate a time-deinterleaved signal by applying time deinterleaving to a received signal corresponding to a broadcast signal frame; a denormalizer configured to increase the power of the received signal or the time-deinterleaved signal by a level corresponding to the power reduction by the power normalizer of the transmitter; a core layer BICM decoder configured to recover core layer data from a signal power-adjusted by the denormalizer; an enhancement layer symbol extractor configured to extract enhancement layer signals by performing elimination corresponding to core layer data on a signal power-adjusted by the denormalizer using the output signal of the core layer FEC decoder of the core layer BICM decoder; a de-injection level controller configured to increase the power of the enhancement layer signal by a level corresponding to the power reduction by the injection level controller of the transmitter; and an enhancement layer BICM decoder configured to recover enhancement layer data using the output signal of the de-injection level controller. In this case, Figure 1 The broadcast signal receiving apparatus 130 shown can be considered to include: an OFDM receiver configured to generate a received signal by performing any one or more of synchronization, channel estimation, and equalization on a transmitted signal corresponding to a broadcast signal frame; a time deinterleaving unit configured to generate a time-deinterleaved signal by applying time deinterleaving to the received signal; a denormalizer configured to increase the power of the received signal or the time-deinterleaved signal to a level corresponding to the power reduction by the power normalizer of the transmitter; a core layer BICM decoder configured to recover core layer data from the signal power-adjusted by the denormalizer; an enhancement layer symbol extractor configured to extract an enhancement layer signal by performing elimination corresponding to core layer data on the signal power-adjusted by the denormalizer using the output signal of the core layer FEC decoder of the core layer BICM decoder; a deinjection level controller configured to increase the power of the enhancement layer signal to a level corresponding to the power reduction by the injection level controller of the transmitter; and an enhancement layer BICM decoder configured to recover enhancement layer data using the output signal of the deinjection level controller.

[0119] In this case, the broadcast signal frame may include a preamble, which may include the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channel, wherein the start position of the first complete FEC block corresponding to each physical layer channel can be used to calculate the position of the first unit before convolutional temporal interleaving.

[0120] Although Figure 1While not explicitly shown, however, in addition to core layer data and enhancement layer data, the broadcast signal transmission / reception system according to embodiments of the present invention can also multiplex / demultiplex one or more pieces of extension layer data. In this case, the extension layer data can be multiplexed at a power level lower than that of the core layer data and enhancement layer data. Furthermore, when two or more extension layers are included, the injection power level of the second extension layer can be lower than that of the first extension layer, and the injection power level of the third extension layer can be lower than that of the second extension layer.

[0121] Figure 2 This is an operational flowchart illustrating a broadcast signal transmission / reception method according to an embodiment of the present invention.

[0122] refer to Figure 2 In the broadcast signal transmission / reception method according to an embodiment of the present invention, in step S210, the core layer signal and the enhancement layer signal are combined at different power levels and then multiplexed to generate a broadcast signal frame, wherein the broadcast signal frame includes time interleaver information shared by the core layer signal and the enhancement layer signal, and a preamble for transmitting the time interleaver information by signal.

[0123] In this scenario, the broadcast signal frame generated in step S210 may include a preamble, a header, and a superimposed payload. In this scenario, at least the preamble and header may include L1 signaling information. In this scenario, the L1 signaling information may include injection level information and normalization factor information.

[0124] In this case, the preamble may include PLP identification information for identifying the physical layer channel (PLP); and layer identification information for identifying the layer corresponding to the layer.

[0125] In this case, PLP identification information and layer identification information can be included in the preamble as distinct fields.

[0126] In this case, time interleaver information can be included in the preamble based on the core layer.

[0127] In this case, based on the comparison between the layer identification information and the predetermined value, the preamble can selectively include injection level information corresponding to the injection level controller for each physical layer channel (PLP).

[0128] In this case, the preamble can include physical layer channel type information, start position information, and size information.

[0129] In this case, type information can be used to identify one of the first type corresponding to non-distributed physical layer channels and the second type corresponding to distributed physical layer channels.

[0130] In this case, non-distributed physical layer channels can be assigned to continuous data unit indexes, and distributed physical layer channels can include two or more sub-slices.

[0131] In this case, for each physical layer channel (PLP), type information can be selectively transmitted by signal based on the comparison result between the layer identification information and a predetermined value.

[0132] In this case, type information can be sent via signals only to the core layer.

[0133] In this case, the starting position information can be the same as the index of the first data unit corresponding to the physical layer channel.

[0134] In this case, the start location information can be indicated by the cell addressing scheme to indicate the start location of the physical layer channel.

[0135] In this case, the start position information can be included in the preamble for each physical layer channel (PLP) without checking the conditions of the conditional statement corresponding to the layer identification information.

[0136] In this case, size information can be generated based on the number of data units allocated to the physical layer channel.

[0137] In this case, size information can be included in the preamble for each physical layer channel (PLP) without checking the conditions of the conditional statement corresponding to the layer identification information.

[0138] In this case, time-interleaved information can be sent using signals based on the core layer.

[0139] In this case, the generation of time-interleaved signals can be performed using a hybrid time-interleaved converter.

[0140] In this case, the physical layer channels (PLPs) of the core layer and enhancement layer can consist of only the complete FEC block.

[0141] In this case, where the boundary between time-interleaved packets does not correspond to the boundary between FEC blocks in the enhancement layer, a preamble can be used to signal information for identifying a portion of an FEC block in the enhancement layer, where the FEC block corresponds to the boundary between time-interleaved packets.

[0142] In this case, the information used to identify a portion of the FEC block may include at least one of the following: the start position information of the physical layer channel (PLP) in the core layer, the start position information of the physical layer channel (PLP) in the enhancement layer, the modulation information corresponding to the enhancement layer, and the FEC type information corresponding to the enhancement layer.

[0143] In this case, the start position information of the physical layer channel (PLP) can correspond to the index of the first data unit of the physical layer channel (PLP).

[0144] In this case, modulation information can only be sent using a signal if the FEC type information meets the predetermined conditions.

[0145] In this case, the enhancement layer signal corresponds to the enhancement layer data, which can be recovered based on elimination corresponding to the recovery of the core layer data, which corresponds to the core layer signal.

[0146] In this case, the generation of time-interleaved signals can be performed using a convolutional time-interleaved converter. The time-interleaved converter group can include a physical layer channel (PLP), wherein the physical layer channel (PLP) includes incomplete FEC blocks, and a preamble can be used to signal the start position information of the first complete FEC block in the physical layer channel (PLP).

[0147] In this case, interleaving can be performed by using one of several operating modes.

[0148] In this case, the operating modes may include a first mode corresponding to no temporal interleaving, a second mode for performing convolutional temporal interleaving, and a third mode for performing mixed temporal interleaving.

[0149] In this case, the preamble may include a field indicating the start position of the first complete FEC block for the first and second modes corresponding to the current physical layer channel, but may not include a field indicating the start position of the first FEC block for the third mode.

[0150] In this case, the field indicating the start position of the first FEC block can be one of the first field used in the first mode and the second field used in the second mode, and the first field and the second field can have different lengths.

[0151] In this case, the length of the second field can be longer than the length of the first field.

[0152] In this case, the length of the first field can be determined based on the length of the LDPC codeword and the modulation order, and the length of the second field can be determined not only by the length of the LDPC codeword and the modulation order but also by further considering the depth of the convolutional time interleaver.

[0153] In this case, the length of the first field can be 15 bits, and the length of the second field can be 22 bits.

[0154] In this case, for each of the core layer corresponding to the core layer signal and the enhancement layer corresponding to the enhancement layer signal, the first field and the second field can be sent by signal respectively.

[0155] In this case, the preamble may include a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channel.

[0156] In this case, the start position of the first complete FEC block can be specified relative to the first unit of each physical layer channel in the physical layer channel.

[0157] In this case, when the operating mode of the time interleaver is the mode corresponding to convolutional time interleaver, the start position of the first complete FEC block can indicate the position of the first cell of the first complete FEC block before convolutional time interleaver, and the position of the first cell of the first complete FEC block can be signaled after convolutional time interleaver.

[0158] In this case, the field indicating the start position of the first complete FEC block can correspond to the position after convolutional temporal interleaving, where the position after convolutional temporal interleaving is calculated by adding the position (C) before convolutional temporal interleaving and the delay caused by convolutional temporal interleaving.

[0159] In this case, the latency caused by convolutional temporal interleaving can be calculated by using the position (L1D_plp_CTI_start_row) of the interleaving selector corresponding to the convolutional temporal interleaving.

[0160] In this case, the delay caused by convolutional temporal interleaving can be calculated by using the modulo operation of the sum of the position of the interleaver selector corresponding to convolutional temporal interleaving and the position before convolutional temporal interleaving (L1D_plp_CTI_start_row+C) and the number of delay lines (N_row) corresponding to convolutional temporal interleaving.

[0161] In this case, the location of the signal transmission interleaver selector can be used only for the core layer physical layer channel corresponding to the core layer, and the location of the signal transmission interleaver selector can be omitted for the enhancement layer physical layer channel corresponding to the enhancement layer.

[0162] In this case, the position of the interleaver selector for the enhancement layer physical layer channel can be calculated by using the position of the interleaver selector that is signaled for the core layer physical layer channel corresponding to the enhancement layer physical layer channel.

[0163] In this case, the field indicating the start position of the first complete FEC block can be 22 bits long.

[0164] In this case, a field indicating the start position of the first complete FEC block can be sent by signaling for each of the core layer physical layer channel and the enhancement layer physical layer channel.

[0165] Furthermore, in the broadcast signal transmission / reception method according to an embodiment of the present invention, in step S220, the broadcast signal frame is transmitted by OFDM.

[0166] Furthermore, in the broadcast signal transmission / reception method according to an embodiment of the present invention, in step S230, the transmission signal is received by OFDM.

[0167] In this case, synchronization, channel estimation, and equalization can be performed in step S230.

[0168] In this case, in step S230, the preamble can be recovered, the preamble can be recovered using the signals included in the recovered preamble, and the data signal can be recovered using the signaling information included in the preamble.

[0169] Furthermore, in the broadcast signal transmission / reception method according to an embodiment of the present invention, in step S240, core layer data is recovered from the received signal.

[0170] Furthermore, in the broadcast signal transmission / reception method according to an embodiment of the present invention, in step S250, enhancement layer data is recovered by eliminating the core layer signal.

[0171] Specifically, Figure 2 Steps S240 and S250 shown can correspond to the demultiplexing operation corresponding to step S210.

[0172] As will be described in detail later, Figure 2Step S210 shown may include: generating a multiplexed signal by combining core layer signals and enhancement layer signals; reducing the power of the multiplexed signal to a power level corresponding to the core layer signals; generating a time-interleaved signal by performing interleaving applied to both the core layer signals and the enhancement layer signals; and generating a broadcast signal frame, wherein the broadcast signal frame includes a preamble for signaling time-interleaved information corresponding to the interleaving. In this case, the operation of generating the multiplexed signal may include combining the core layer signals and enhancement layer signals at different power levels. In this case, the preamble may include a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channels. In this scenario, the broadcast signal transmission method in steps S210 and S220 can be considered to include: generating a multiplexed signal by combining core layer signals and enhancement layer signals; reducing the power of the multiplexed signal to a power level corresponding to the core layer signal; generating a time-interleaved signal by performing interleaving applied to both the core layer signal and the enhancement layer signal; generating a broadcast signal frame, wherein the broadcast signal frame includes a preamble for signaling time-interleaved information corresponding to the interleaving; and transmitting the broadcast signal frame via an antenna using an OFDM communication scheme. In this scenario, the operation of generating the multiplexed signal may include combining the core layer signal and enhancement layer signal at different power levels. In this scenario, the preamble may include a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channels.

[0173] As will be described in detail later, Figure 2Steps S240 and S250 shown may include: generating a time-deinterleaved signal by applying time deinterleaving to a received signal corresponding to a broadcast signal frame; increasing the power of the received signal or the time-deinterleaved signal to a level corresponding to the power reduced by the transmitter's power normalizer; recovering core layer data from the power-adjusted signal; extracting an enhancement layer signal by performing cancellation on the power-adjusted signal corresponding to the core layer data; increasing the power of the enhancement layer signal to a level corresponding to the power reduced by the transmitter's injection level controller; and recovering the enhancement layer data using the power-adjusted enhancement signal. In this context, the broadcast signal receiving method according to an embodiment of the present invention can be considered to include: generating a received signal by performing synchronization, channel estimation, and equalization on a transmitted signal corresponding to a broadcast signal frame; generating a time-deinterleaved signal by applying time deinterleaving to the received signal; increasing the power of the received signal or the time-deinterleaved signal to a level corresponding to the power reduction by the transmitter's power normalizer; recovering core layer data from the power-adjusted signal; extracting an enhancement layer signal by performing cancellation corresponding to the core layer data on the power-adjusted signal; increasing the power of the enhancement layer signal to a level corresponding to the power reduction by the transmitter's injection level controller; and recovering enhancement layer data using the power-adjusted enhancement layer signal.

[0174] In this case, the broadcast signal frame may include a preamble, which may include the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channel, and the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channel can be used to calculate the position of the first unit before convolutional temporal interleaving.

[0175] Figure 3 It is shown Figure 1 A block diagram of an example of a device for generating broadcast signal frames.

[0176] refer to Figure 3 According to an embodiment of the present invention, an apparatus for generating broadcast signal frames may include a core layer BICM unit 310, an enhancement layer BICM unit 320, an injection level controller 330, a combiner 340, a power normalizer 345, a time interleaver 350, a signaling generation unit 360, and a frame builder 370.

[0177] Typically, BICM devices include an error correction encoder, a bit interleaver, and a symbol mapper. Figure 3 Each of the core layer BICM unit 310 and the enhancement layer BICM unit 320 shown can include an error correction encoder, a bit interleaver, and a symbol mapper. Specifically, Figure 3Each error correction encoder shown (core layer FEC encoder and enhancement layer FEC encoder) can be formed by connecting the BCH encoder and the LDPC encoder in series. In this case, the input of the error correction encoder is input to the BCH encoder, the output of the BCH encoder is input to the LDPC encoder, and the output of the LDPC encoder can be the output of the error correction encoder.

[0178] like Figure 3 As shown, core layer data and enhancement layer data are processed through their respective BICM units and then combined by combiner 340. That is, the term "Layer Demultiplexing (LDM)" used here can refer to combining multiple data streams from multiple layers into a single data stream using power differences, and then transmitting the combined data.

[0179] In other words, core layer data passes through core layer BICM unit 310, enhancement layer data passes through enhancement layer BICM unit 320, and then through injection level controller 330. The core layer data and enhancement layer data are then combined by combiner 340. In this configuration, enhancement layer BICM unit 320 can perform BICM encoding different from that of core layer BICM unit 310. Specifically, enhancement layer BICM unit 320 can perform error correction encoding or symbol mapping at a higher bit rate than core layer BICM unit 310. Furthermore, enhancement layer BICM unit 320 can perform error correction encoding or symbol mapping that is less robust than that of core layer BICM unit 310.

[0180] For example, a core layer error correction encoder can exhibit a lower bit rate than an enhancement layer error correction encoder. In this case, the enhancement layer symbol mapper may be less robust than the core layer symbol mapper.

[0181] The combiner 340 can be viewed as functioning to combine the core layer signal and the enhancement layer signal at different power levels. In one embodiment, power level adjustment can be performed on the core layer signal instead of the enhancement layer signal. In this case, the power of the core layer signal can be adjusted to be higher than that of the enhancement layer signal.

[0182] Core layer data can use forward error correction (FEC) codes with low coding rates to perform robust reception, while enhancement layer data can use FEC codes with high coding rates to achieve high data transmission rates.

[0183] In other words, in the same receiving environment, core layer data can have a wider coverage area than enhancement layer data.

[0184] The enhancement layer data, which has been passed through the enhancement layer BICM unit 320, has its gain (or power) adjusted by the injection level controller 330 and combined with the core layer data by the combiner 340.

[0185] In other words, the injection level controller 330 generates a power-reduced enhancement layer signal by reducing the power of the enhancement layer signal. In this case, the amplitude of the signal adjusted by the injection level controller 330 can be determined based on the injection level. In this case, when signal B is inserted into signal A, the injection level can be defined by the following Equation 1:

[0186]

[0187] For example, when an enhancement layer signal is inserted into a core layer signal, assuming the injection level is 3dB, Equation 1 means that the enhancement layer signal has half the power of the core layer signal.

[0188] In this case, the injection level controller 330 can adjust the power level of the enhancement layer signal from 0dB to 25.0dB in increments of 0.5dB or 1dB.

[0189] Typically, the transmit power allocated to the core layer is higher than that allocated to the enhancement layer, which enables the receiver to decode the core layer data first.

[0190] In this case, combiner 340 can be considered as generating multiplexed signals by combining core layer signals with power-reduced enhancement layer signals.

[0191] The signal obtained by combining the signals through combiner 340 is provided to power normalizer 345, which reduces the signal power to a level corresponding to the power increase caused by the combination of the core layer signal and the enhancement layer signal, and then performs power adjustment. In other words, power normalizer 345 reduces the power of the signal multiplexed by combiner 340 to the power level corresponding to the core layer signal. Because the level of the combined signal is higher than that of a single-layer signal, power normalizer 345 is needed to normalize the power to prevent amplitude limiting and other issues in the remainder of the broadcast signal transmission / reception system.

[0192] In this case, the power normalizer 345 can adjust the amplitude of the combined signal to an appropriate value by multiplying the amplitude of the combined signal by the normalization factor in Equation 2 below. The injection level information used to calculate Equation 2 below can be transmitted to the power normalizer 345 via a signaling stream:

[0193]

[0194] Assuming that the enhancement layer signal S is injected at a preset level E Injected signal S into the core layer C When the power levels of the core layer signal and the enhancement layer signal are normalized to 1, the combined signal can be obtained from S. C+αS E express.

[0195] In this case, α is a scaling factor corresponding to various injection levels. That is, the injection level controller 330 can correspond to a scaling factor.

[0196] For example, when the injection level of the enhancement layer is 3dB, the combined signal can be generated by... express.

[0197] Since the power of the combined signal (multiplexed signal) increases compared to the core layer signal, the power normalizer 345 needs to mitigate the increase in power.

[0198] The output of the power normalizer 345 can be determined by β(S) C +αS E )express.

[0199] In this case, β is a normalization factor based on the various injection levels of the enhancement layer.

[0200] When the injection level of the enhancement layer is 3dB, the power of the combined signal increases by 50% compared to the power of the core layer signal. Therefore, the output of the power normalizer 345 can be determined by... express.

[0201] Table 1 below lists the scaling factor α and normalization factor β for various injection levels (CL: core layer, EL: enhancement layer). The relationship between injection level, scaling factor α, and normalization factor β can be defined by the following Equation 3:

[0202]

[0203] Table 1

[0204]

[0205]

[0206] In other words, the power normalizer 345 corresponds to the normalization factor and reduces the power of the multiplexed signal to the level that the combiner 340 has increased the power of.

[0207] In this case, each of the normalization factor and the scaling factor can be a rational number greater than 0 and less than 1.

[0208] In this case, the scaling factor can decrease as the power corresponding to the injection level controller 330 decreases, and the normalization factor can increase as the power corresponding to the injection level controller 330 decreases.

[0209] The power-normalized signal is distributed to burst errors occurring on the channel via time interleaver 350.

[0210] In this configuration, the time interleaver 350 can be viewed as performing interleaving on both the core layer signal and the enhancement layer signal. That is, the core layer and enhancement layer share the time interleaver, thereby preventing unnecessary memory usage and reducing latency at the receiver.

[0211] Although described in more detail later, the enhancement layer signal may correspond to enhancement layer data recovered based on elimination corresponding to the recovery of core layer data, wherein the core layer data corresponds to the core layer signal. Combiner 340 may combine one or more extended layer signals with power levels lower than the core layer signal and enhancement layer signal, along with the core layer signal and enhancement layer signal.

[0212] Simultaneously, L1 signaling information, including injected level information, is encoded by a signaling generation unit 360, which includes a dedicated signaling BICM. In this case, the signaling generation unit 360 can receive injected level information IL INFO from the injected level controller 330 and can generate an L1 signaling signal.

[0213] In L1 signaling, L1 refers to Layer 1, the lowest layer in the ISO 7-layer model. In this case, L1 signaling can be included in the preamble.

[0214] Typically, L1 signaling may include FFT size, guard interval size, etc. (i.e., important parameters of OFDM transmitters), channel code rate, modulation information, etc. (i.e., important parameters of BICM). This L1 signaling signal is combined with the data signal to form a broadcast signal frame.

[0215] Frame builder 370 generates broadcast signal frames by combining L1 signaling signals with data signals. In this case, frame builder 370 can use time-interleaved signals to generate broadcast signal frames, wherein the broadcast signal frames include a preamble used to transmit physical layer channel (PLP) size information and time-interleaved information shared by core layer signals and enhancement layer signals. In this case, the broadcast signal frames may further include a preamble.

[0216] In this case, frame builder 370 can generate a broadcast signal frame, wherein the broadcast signal frame includes a preamble for signaling time interleaver information corresponding to time interleaver 350.

[0217] In this scenario, time interleaver 350 can use one of the time interleaver groups, and the boundary between time interleaver groups can be the boundary between the physical layer channels (PLPs) of the core layer corresponding to the core layer signal. That is, one of the boundaries between the physical layer channels (PLPs) of the core layer can be the boundary between time interleaver groups.

[0218] In this case, time-interleaved information can be sent using signals based on the core layer.

[0219] According to one embodiment, a portion of the time-interleaved information can be signaled based on the core layer, and another portion of the time-interleaved information can be signaled regardless of the layer.

[0220] In other words, signal transmission time interleaver information can be used based on the layer identification information corresponding to the core layer.

[0221] In this case, the time interleaver 350 can correspond to a hybrid time interleaver. In this case, the physical layer channels (PLPs) of the core layer and enhancement layer can consist of only complete FEC blocks.

[0222] In this case, where the boundary between time-interleaved packets does not correspond to the boundary between FEC blocks in the enhancement layer, a preamble can be used to signal information for identifying a portion of an FEC block in the enhancement layer, where the FEC block corresponds to the boundary between time-interleaved packets.

[0223] In this case, the information used to identify a portion of the FEC block may include at least one of the following: the start position information of the physical layer channel (PLP) in the core layer, the start position information of the physical layer channel (PLP) in the enhancement layer, the modulation information corresponding to the enhancement layer, and the FEC type information corresponding to the enhancement layer.

[0224] In this case, the start position information of the physical layer channel (PLP) can correspond to the index of the first data unit of the physical layer channel (PLP).

[0225] In this case, modulation information can only be sent using a signal if the FEC type information meets the predetermined conditions.

[0226] In this case, the enhancement layer signal can correspond to the enhancement layer data recovered based on the elimination corresponding to the recovery of the core layer data, wherein the core layer data corresponds to the core layer signal.

[0227] In this case, the time interleaver 350 can correspond to a convolutional time interleaver, the time interleaver group can include a physical layer channel (PLP) containing incomplete FEC blocks, and the preamble can be used to signal the start position information of the first complete FEC block in the physical layer channel (PLP).

[0228] In this case, the start position of the first complete FEC block can be specified relative to the first unit of each physical layer channel in the physical layer channel.

[0229] In this case, when the operating mode of the time interleaver is the mode corresponding to convolutional time interleaver, the start position of the first complete FEC block can indicate the first cell of the first complete FEC block before convolutional time interleaver, and the position of the first cell of the first complete FEC block can be signaled after convolutional time interleaver.

[0230] In this case, the field indicating the start position of the first complete FEC block can correspond to the position after convolutional temporal interleaving, where the position after convolutional temporal interleaving is calculated by adding the position (C) before convolutional temporal interleaving and the delay caused by convolutional temporal interleaving.

[0231] In this case, the latency caused by convolutional temporal interleaving can be calculated by using the position (L1D_plp_CTI_start_row) of the interleaving selector corresponding to the convolutional temporal interleaving.

[0232] In this case, the delay caused by convolutional temporal interleaving can be calculated by using the modulo operation of the sum of the position of the interleaver selector corresponding to convolutional temporal interleaving and the position before convolutional temporal interleaving (L1D_plp_CTI_start_row+C) and the number of delay lines (N_row) corresponding to convolutional temporal interleaving.

[0233] In this case, the location of the signal transmission interleaver selector can be used only for the core layer physical layer channel corresponding to the core layer, and the location of the signal transmission interleaver selector can be omitted for the enhancement layer physical layer channel corresponding to the enhancement layer.

[0234] In this case, the position of the interleaver selector for the enhancement layer physical layer channel can be calculated by using the position of the interleaver selector that is signaled for the core layer physical layer channel corresponding to the enhancement layer physical layer channel.

[0235] In this case, the field indicating the start position of the first complete FEC block can be 22 bits long.

[0236] In this case, a field indicating the start position of the first complete FEC block can be sent by signaling for each of the core layer physical layer channel and the enhancement layer physical layer channel.

[0237] In this case, the time interleaver 350 can perform interleaving by using one of a number of operating modes.

[0238] In this case, the operating modes may include: a first mode corresponding to no temporal interleaving (L1D_plp_TI_mode=00), a second mode for performing convolutional temporal interleaving (L1D_plp_TI_mode=01), and a third mode for performing mixed temporal interleaving (L1D_plp_TI_mode=10).

[0239] In this case, the preamble may include a field indicating the start position of the first complete FEC block for the first and second modes corresponding to the current physical layer channel, but may not include a field indicating the start position of the first FEC block for the third mode.

[0240] In this scenario, the field indicating the start position of the first FEC block can be either the first field (L1D_plp_fec_block_start) used in the first mode (L1D_plp_TI_mode=00) or the second field (L1D_plp_CTI_fec_block_start) used in the second mode (L1D_plp_TI_mode=01), and the first and second fields can have different lengths. In this case, the first field (L1D_plp_fec_block_start) can indicate the start position of the first FEC block that begins in the current physical layer channel during the current subframe, and the second field (L1D_plp_CTI_fec_block_start) can indicate the start position of the first complete FEC block that leaves the current physical layer channel of the convolutional temporal interleaver in the current subframe or a subsequent subframe. In this scenario, both the first field (L1D_plp_fec_block_start) and the second field (L1D_plp_CTI_fec_block_start) can be signaled after interleaving. Specifically, in the case of the second field (L1D_plp_CTI_fec_block_start), when signaling is performed based on interleaving, the number of bits required for signaling may increase.

[0241] In this case, the length of the second field can be longer than the length of the first field.

[0242] In this case, the length of the first field can be determined based on the length of the LDPC codeword and the modulation order, and the length of the second field can be determined not only by the length of the LDPC codeword and the modulation order but also by further considering the depth of the convolutional time interleaver.

[0243] In this case, the length of the first field can be 15 bits, and the length of the second field can be 22 bits.

[0244] In this case, for each of the core layer corresponding to the core layer signal and the enhancement layer corresponding to the enhancement layer signal, the first field and the second field can be sent by signal respectively.

[0245] In this case, frame builder 370 may include a preamble generator configured to generate a preamble, a preamble generator configured to generate a preamble, and a superimposed payload generator configured to generate a superimposed payload corresponding to a time-interleaved signal.

[0246] In this case, the preamble can be shorter than the preamble and has a fixed length.

[0247] In this case, the preamble may include symbols representing the structure of the preamble, wherein the symbols correspond to a fixed-length bit string representing a combination of modulation scheme / coding rate, FFT size, guard interval length, and pilot pattern of the preamble.

[0248] In this case, the symbol can correspond to a lookup table, in which a preamble structure corresponding to the second FFT size is assigned before the preamble structure corresponding to the first FFT size. When the modulation scheme / coding rate is the same, the second FFT size is smaller than the first FFT size. Furthermore, a preamble structure corresponding to the second guard interval length is assigned before the preamble structure corresponding to the first guard interval length. When the modulation scheme / coding rate is the same and the FFT size is the same, the second guard interval length is longer than the first guard interval length.

[0249] Broadcast signal frames can be transmitted via OFDM transmitters that are robust to multipath and Doppler phenomena. In this case, the OFDM transmitter can be considered as responsible for generating the transmission signal for the next-generation broadcast system.

[0250] In this case, the preamble may include PLP identification information for identifying the physical layer channel (PLP); and layer identification information for identifying the layer corresponding to the layer.

[0251] In this case, PLP identification information and layer identification information can be included in the preamble as distinct fields.

[0252] In this case, time interleaver information can be included in the preamble based on the core layer.

[0253] In this case, based on the comparison result of the layer identification information and the predetermined value (IF(j>0)), the preamble can selectively include injection level information corresponding to the injection level controller for each physical layer channel (PLP).

[0254] In this case, the preamble can include physical layer channel type information, start position information, and size information.

[0255] In this case, type information can be used to identify one of the first type corresponding to non-distributed physical layer channels and the second type corresponding to distributed physical layer channels.

[0256] In this case, non-distributed physical layer channels can be assigned to continuous data unit indexes, and distributed physical layer channels can include two or more sub-slices.

[0257] In this case, for each physical layer channel (PLP), type information can be selectively transmitted by signal based on the comparison result between the layer identification information and a predetermined value.

[0258] In this case, type information can be sent via signals only to the core layer.

[0259] In this case, the starting position information can be the same as the index of the first data unit corresponding to the physical layer channel.

[0260] In this case, the start location information can be indicated by the cell addressing scheme to indicate the start location of the physical layer channel.

[0261] In this case, the start position information can be included in the preamble for each physical layer channel (PLP) without checking the conditions of the conditional statement corresponding to the layer identification information.

[0262] In this case, size information can be generated based on the number of data units allocated to the physical layer channel.

[0263] In this case, size information can be included in the preamble used for each physical layer channel (PLP) without checking the conditions of the conditional statement corresponding to the layer identification information.

[0264] Figure 4 This is a diagram illustrating an example of the structure of a broadcast signal frame.

[0265] refer to Figure 4 The broadcast signal frame includes a preamble 410, a preamble 420, and a superimposed payload 430.

[0266] Figure 4 The frames shown can be included in a superframe.

[0267] In this case, a broadcast signal frame may include at least one OFDM symbol. A broadcast signal frame may include a reference symbol or a pilot symbol.

[0268] The frame structures that utilize Layered Multiplexing (LDM) include, for example: Figure 4 The shown are the preamble 410, the preamble 420, and the superimposed payload 430.

[0269] In this case, preamble 410 and preamble 420 can be regarded as two levels of preambles.

[0270] In this case, the preamble 410 can have a shorter length than the preamble 420 for faster acquisition and detection. Alternatively, the preamble 410 can have a fixed length. In this case, the preamble can include symbols of fixed length. For example, the preamble 410 can consist of four OFDM symbols, each with a length of 0.5 ms, thus allowing the preamble 410 to correspond to a fixed time length of 2 ms.

[0271] In this case, the preamble 410 can have a fixed bandwidth, and the preamble 420 and the superimposed payload 430 can have a wider variable bandwidth than the preamble 410.

[0272] Preamble 420 can use robust LDPC codes to send detailed signaling information. In this case, the length of preamble 420 can vary depending on the signaling information.

[0273] In this case, both the preamble 410 and the superimposed payload 430 can be regarded as a common signal shared by multiple layers.

[0274] The superimposed payload 430 can correspond to a multiplexed signal of at least two layers. In this case, the superimposed payload 430 can be generated by combining the core layer payload and the enhancement layer payload at different power levels. In this case, the core layer payload may include an in-band signaling portion. In this case, the in-band signaling portion may include signaling information for enhancement layer services.

[0275] In this case, preamble 410 may include symbols representing the preamble structure.

[0276] In this case, the symbols included in the preamble to represent the preamble structure can be set as shown in Table 2 below.

[0277] Table 2

[0278]

[0279]

[0280]

[0281]

[0282] For example, a fixed-length code of 7 bits can be assigned to represent the preamble structure shown in Table 2.

[0283] The L1-basic mode 1, L1-basic mode 2 and L1-basic mode 3 in Table 2 can correspond to QPSK and 3 / 15LDPC.

[0284] The L1 basic mode 4 in Table 2 can correspond to 16-NUC (non-uniform constellation) and 3 / 15LDPC.

[0285] The L1 basic mode 5 in Table 2 can correspond to 64-NUC (non-uniform constellation) and 3 / 15LDPC.

[0286] In Table 2, L1-basic mode 6 and L1-basic mode 7 can correspond to 256-NUC (non-uniform constellation) and 3 / 15LDPC. Thereafter, modulation scheme / coding rate represents a combination of modulation schemes and coding rates such as QPSK and 3 / 15LDPC.

[0287] The FFT size in Table 2 can represent the size of the Fast Fourier Transform.

[0288] The GI length in Table 2 can represent the length of the protection interval, or the length of the non-data protection interval in the time domain. In this case, the longer the protection interval, the more robust the system.

[0289] The pilot patterns in Table 2 can represent the pilot pattern's Dx. Although not explicitly shown in Table 2, in the examples therein, Dy can be all 1. For example, Dx = 3 could mean that a pilot for channel estimation is included every three symbols in the x-axis direction. For example, Dy = 1 could mean that a pilot is included every three symbols in the y-axis direction.

[0290] As shown in Table 2, a preamble structure corresponding to a more robust second modulation scheme / coding rate than the first modulation scheme / coding rate can be assigned in the lookup table before the preamble structure corresponding to the first modulation scheme / coding rate.

[0291] In this case, being assigned before other preamble structures can mean being stored in the lookup table as a sequence number corresponding to a sequence number smaller than the other preamble structures.

[0292] Furthermore, under the same modulation scheme / coding rate, a preamble structure corresponding to a shorter FFT size than the first FFT size can be assigned in a lookup table before the preamble structure corresponding to the first FFT size.

[0293] Furthermore, under the same modulation scheme / coding rate and the same FFT size, a preamble structure corresponding to a second guard interval that is longer than the first guard interval can be assigned in a lookup table before the preamble structure corresponding to the first guard interval.

[0294] As shown in Table 2, the setting of the order in which the preamble structure is assigned in the lookup table can make the recognition of the preamble structure using the preamble more efficient.

[0295] Figure 5 It is shown Figure 4 The diagram illustrates an example of the reception and processing of a broadcast signal frame.

[0296] refer to Figure 5 The preamble 510 is detected and demodulated, and the signaling information is reconstructed by demodulating the preamble 520 with the demodulated information.

[0297] Signaling information is used to demodulate core layer data 530, and enhancement layer signals are demodulated through cancellation processing corresponding to the core layer data. The cancellation process corresponding to the core layer data will be described in detail later.

[0298] Figure 6 It is shown Figure 4 The diagram illustrates yet another example of the reception processing of the broadcast signal frame shown.

[0299] refer to Figure 6 The preamble 610 is detected and demodulated, and the signaling information is reconstructed by demodulating the preamble 620 with the demodulated information.

[0300] Signaling information is used to demodulate core layer data 630. In this case, core layer data 630 includes an in-band signaling portion 650. The in-band signaling portion 650 includes signaling information for enhancement layer services. Bandwidth is used more efficiently through the in-band signaling portion 650. In this case, the in-band signaling portion 650 can be included in the core layer, which is more robust than the enhancement layer.

[0301] exist Figure 6 In the example, basic signaling information and information for core layer services can be transmitted via preamble 620, and signaling information for enhancement layer services can be transmitted via in-band signaling portion 650.

[0302] The enhancement layer signal is demodulated through elimination processing corresponding to the core layer data.

[0303] In this case, the signaling information can be L1 (Layer 1) signaling information. L1 signaling information may include information for physical layer parameters.

[0304] refer to Figure 4 Broadcast signal frames include L1 signaling signals and data signals. For example, a broadcast signal frame can be an ATSC 3.0 frame.

[0305] Figure 7 It is shown Figure 1 A block diagram of yet another example of the apparatus for generating broadcast signal frames shown.

[0306] refer to Figure 7 As can be seen, in addition to the core layer data and the enhancement layer data, the device used to generate broadcast signal frames also reuses data corresponding to N (N is a natural number equal to or greater than 1) extension layers.

[0307] In other words, besides the core layer BICM unit 310, the enhancement layer BICM unit 320, the injection level controller 330, the combiner 340, the power normalizer 345, the time interleaver 350, the signaling generation unit 360, and the frame builder 370, Figure 7 The apparatus for generating broadcast signal frames also includes N extended layer BICM units 410, ..., 430 and injection level controllers 440, ..., 460.

[0308] Already referenced Figure 3 Detailed description Figure 7 The core layer BICM unit 310, enhancement layer BICM unit 320, injection level controller 330, combiner 340, power normalizer 345, time interleaver 350, signaling generation unit 360, and frame builder 370 are shown.

[0309] Each of the N extended layer BICM units 410, ..., 430 independently performs BICM encoding, and each of the injection level controllers 440, ..., 460 performs power reduction corresponding to the corresponding extended layer, thereby enabling the power-reduced extended layer signal to be combined with other layer signals via combiner 340.

[0310] In this case, each of the error correction encoders in the extended layer BICM units 410, ..., 430 can be formed by connecting the BCH encoder and the LDPC encoder in series.

[0311] Specifically, preferably, the power reduction corresponding to each injection level controller 440, ..., 460 is higher than the power reduction of injection level controller 330. That is to say, Figure 7The lower of the injection level controllers 330, 440, ..., 460 shown can correspond to a greater power reduction.

[0312] Depend on Figure 7 The injection level information provided by the injection level controllers 330, 440, and 460 shown is included in the broadcast signal frame of the frame builder 370 via the signaling generation unit 360 and then sent to the receiver. That is, the injection level of each layer is included in the L1 signaling information and then transmitted to the receiver.

[0313] In this invention, the power adjustment can correspond to an increase or decrease in the power of the input signal, and can also correspond to an increase or decrease in the gain of the input signal.

[0314] The power normalizer 345 mitigates the power increase caused by the combination of multiple layer signals by means of the combiner 340.

[0315] exist Figure 7 In the example shown, the power normalizer 345 can adjust the power of the signal to an appropriate amplitude by multiplying the amplitude of the signal formed by combining the signals from the individual layers by a normalization factor obtained using Equation 4 below:

[0316]

[0317] The time interleaver 350 performs interleaving of signals equally applied to multiple layers by interleaving the signals combined by the combiner 340.

[0318] Figure 8 It is shown Figure 1 The block diagram shows another example of a signal demultiplexer.

[0319] refer to Figure 8 According to an embodiment of the present invention, the signal demultiplexer includes a time deinterleaver 510, a denormalizer 1010, a core layer BICM decoder 520, an enhancement layer symbol extractor 530, a deinjection level controller 1020, and an enhancement layer BICM decoder 540.

[0320] in this case, Figure 8 The signal demultiplexer shown can be used with Figure 3 This corresponds to the apparatus shown for generating broadcast signal frames.

[0321] The time deinterleaver 510 receives received signals from the OFDM receiver to perform operations such as time / frequency synchronization, channel estimation, and equalization, and performs operations related to the distribution of burst errors occurring on the channel. In this case, L1 signaling information is first decoded by the OFDM receiver and then used for data decoding. Specifically, the injection level information of the L1 signaling information can be transmitted to the denormalizer 1010 and the de-injection level controller 1020. In this case, the OFDM receiver can decode the received signal in the form of a broadcast signal frame (e.g., an ATSC 3.0 frame), extract the data symbol portion of the frame, and provide the extracted data symbol portion to the time deinterleaver 510. That is, the time deinterleaver 510 distributes burst errors occurring on the channel by performing deinterleaving while transmitting data symbols.

[0322] In this case, the time deinterleaver 510 can perform operations corresponding to the time interleaver. In this case, the time deinterleaver 510 can perform deinterleaving by using one of a plurality of operating modes, and can perform deinterleaving by using time interleaver information related to the operation of the time interleaver transmitted by signals.

[0323] The denormalizer 1010 corresponds to the transmitter's power normalizer and increases the power by the level that the power normalizer has reduced. That is, the denormalizer 1010 divides the received signal by the normalization factor in Equation 2.

[0324] Despite Figure 8 In the example shown, denormalizer 1010 is illustrated as adjusting the power of the output signal of time interleaver 510, but in some embodiments, denormalizer 1010 may be located before time interleaver 510, such that power adjustment is performed before interleaving.

[0325] In other words, the denormalizer 1010 can be considered to be located before or after the time interleaver 510, and amplifies the amplitude of the signal to achieve the purpose of LLR calculation of the core layer symbol demapper.

[0326] The output of the time deinterleaver 510 (or the output of the denormalizer 1010) is provided to the core layer BICM decoder 520, and the core layer BICM decoder 520 recovers the core layer data.

[0327] In this configuration, the core layer BICM decoder 520 includes a core layer symbol demapper, a core layer bit deinterleaver, and a core layer error correction decoder. The core layer symbol demapper calculates the symbol-related LLR value, the core layer bit deinterleaver strongly mixes the calculated LLR value with the burst error, and the core layer error correction decoder corrects errors occurring on the channel.

[0328] In this scenario, the core layer symbol demapper can use a predetermined constellation to calculate the LLR value for each bit. The constellation used by the core layer symbol mapper can vary depending on the combination of the coding rate and modulation order used by the transmitter.

[0329] In this case, the core layer bit deinterleaver can perform deinterleaving on the calculated LLR value based on the LDPC codeword.

[0330] Specifically, the core layer error correction decoder can output only information bits, or it can output all bits that have been mixed with parity bits. In the latter case, the core layer error correction decoder can output only information bits as core layer data, and can output all bits that have been mixed with parity bits to the enhancement layer symbol extractor 530.

[0331] A core-layer error correction decoder can be formed by cascading a core-layer LDPC decoder and a core-layer BCH decoder. That is, the input to the core-layer error correction decoder can be fed into the core-layer LDPC decoder, the output of the core-layer LDPC decoder can be fed into the core-layer BCH decoder, and the output of the core-layer BCH decoder can become the output of the core-layer error correction decoder. In this configuration, the LDPC decoder performs LDPC decoding, and the BCH decoder performs BCH decoding.

[0332] Furthermore, an enhancement layer error correction decoder can be formed by cascading the enhancement layer LDPC decoder and the enhancement layer BCH decoder. That is, the input to the enhancement layer error correction decoder can be fed into the enhancement layer LDPC decoder, the output of the enhancement layer LDPC decoder can be fed into the enhancement layer BCH decoder, and the output of the enhancement layer BCH decoder can become the output of the enhancement layer error correction decoder.

[0333] The enhancement layer symbol extractor 530 can receive all bits from the core layer error correction decoder of the core layer BICM decoder 520, and can extract enhancement layer symbols from the output signal of the time deinterleaving unit 510 or the denormalizer 1010. In one embodiment, the enhancement layer symbol extractor 530 may not receive all bits from the error correction decoder of the core layer BICM decoder 520, but may receive LDPC information bits or BCH information bits from the error correction decoder of the core layer BICM decoder 520.

[0334] In this configuration, the enhancement layer symbol extractor 530 includes a buffer, a subtractor, a core layer symbol mapper, and a core layer bit interleaver. The buffer stores the output signal of either the time deinterleaver 510 or the denormalizer 1010. The core layer bit interleaver receives all bits (information bits + parity bits) from the core layer BICM decoder and performs the same core layer bit interleaving as the transmitter. The core layer symbol mapper generates the same core layer symbols as the transmitter from the interleaved signal. The subtractor obtains the enhancement layer symbols by subtracting the output signal of the core layer symbol mapper from the signal stored in the buffer and transmits the enhancement layer symbols to the de-injection level controller 1020. Specifically, when LDPC information bits are provided, the enhancement layer symbol extractor 530 may further include a core layer LDPC encoder. Furthermore, when BCH information bits are provided, the enhancement layer symbol extractor 530 may further include not only a core layer LDPC encoder but also a core layer BCH encoder.

[0335] In this case, the core layer LDPC encoder, core layer BCH encoder, core layer bit interleaver, and core layer symbol mapper included in the enhancement layer symbol extractor 530 can be referenced. Figure 3 The LDPC encoder, BCH encoder, bit interleaver, and symbol mapper described in the core layer are the same.

[0336] The de-injection level controller 1020 receives enhancement layer symbols and increases the power of the input signal to a level that the transmitter's injection level controller has already reduced. In other words, the de-injection level controller 1020 amplifies the input signal and provides the amplified input signal to the enhancement layer BICM decoder 540. For example, if at the transmitter, the power used to combine the enhancement layer signals is 3dB lower than the power used to combine the core layer signals, the de-injection level controller 1020 activates to increase the power of the input signal by 3dB.

[0337] In this case, the de-injection level controller 1020 can be considered as receiving injection level information from the OFDM receiver and multiplying the extracted enhancement layer signal by the enhancement layer gain in Equation 5:

[0338]

[0339] The enhancement layer BICM decoder 540 receives enhancement layer symbols whose power is increased by the de-injection level controller 1020 and recovers the enhancement layer data.

[0340] In this configuration, the enhancement layer BICM decoder 540 may include an enhancement layer symbol demapper, an enhancement layer bit deinterleaver, and an enhancement layer error correction decoder. The enhancement layer symbol demapper calculates the LLR value associated with the enhancement layer symbols, the enhancement layer bit deinterleaver strongly mixes the calculated LLR value with burst errors, and the enhancement layer error correction decoder corrects errors occurring on the channel.

[0341] Although the task performed by the enhancement layer BICM decoder 540 is similar to that performed by the core layer BICM decoder 520, the enhancement layer LDPC decoder typically performs LDPC decoding with a coding rate equal to or greater than 6 / 15.

[0342] For example, the core layer can use LDPC codes with a coding rate equal to or greater than 5 / 15, and the enhancement layer can use LDPC codes with a coding rate equal to or greater than 6 / 15. In this case, in a receiving environment where the enhancement layer data can be decoded, the core layer data can be decoded using only a small number of LDPC decoding iterations. Taking advantage of this characteristic, the core layer and enhancement layer share a single LDPC decoder in the receiver hardware, thereby reducing the cost required to implement the hardware. In this scenario, the core layer LDPC decoder can use only some time resources (LDPC decoding iterations), while the enhancement layer LDPC decoder can use the majority of the time resources.

[0343] In other words, Figure 8 The signal demultiplexer shown first recovers the core layer data by eliminating core layer symbols from the received signal symbols, leaving only enhancement layer symbols, and then recovers the enhancement layer data by increasing the power of the enhancement layer symbols. (See reference...) Figure 3 and Figure 5 As mentioned above, different power level combinations correspond to the signals of each layer, so data recovery with minimal error can only be achieved by starting the recovery from the signal with the strongest power combination.

[0344] Therefore, in Figure 8In the example shown, the signal demultiplexer may include: a time deinterleaver 510 configured to generate a time-deinterleaved signal by applying time deinterleaving to the received signal; a denormalizer 1010 configured to increase the power of the received signal or the time-deinterleaved signal to a level corresponding to the power reduction by the transmitter's power normalizer; a core layer BICM decoder 520 configured to recover core layer data from the signal power-adjusted by the denormalizer 1010; an enhancement layer symbol extractor 530 configured to extract the enhancement layer signal by performing elimination corresponding to core layer data on the signal power-adjusted by the denormalizer 1010 using the output signal of the core layer FEC decoder of the core layer BICM decoder 520; a deinjection level controller 1020 configured to increase the power of the enhancement layer signal to a level corresponding to the power reduction by the transmitter's injection level controller; and an enhancement layer BICM decoder 540 configured to recover the enhancement layer data using the output signal of the deinjection level controller 1020.

[0345] In this scenario, the enhancement layer symbol extractor can receive all codewords from the core layer LDPC decoder of the core layer BICM decoder and can immediately perform bit interleaving on all codewords.

[0346] In this scenario, the enhancement layer symbol extractor can receive information bits from the core layer LDPC decoder of the core layer BICM decoder, perform core layer LDPC encoding on the information bits, and then perform bit interleaving.

[0347] In this scenario, the enhancement layer symbol extractor can receive information bits from the core layer BCH decoder of the core layer BICM decoder, and can perform core layer BCH encoding and core layer LDPC encoding on the information bits, and then perform bit interleaving.

[0348] In this case, the denormalizer and de-injection level controller can receive injection level information IL INFO provided based on L1 signaling, and can perform power control based on the injection level information.

[0349] In this scenario, the core layer BICM decoder can have a lower bit rate than the enhancement layer BICM decoder and can be more robust than the enhancement layer BICM decoder.

[0350] In this case, the denormalizer can correspond to the reciprocal of the normalization factor.

[0351] In this case, the de-injection level controller can correspond to the reciprocal of the scaling factor.

[0352] In this case, enhancement layer data can be recovered based on the elimination corresponding to the recovery of core layer data, where the core layer data corresponds to the core layer signal.

[0353] In this configuration, the signal demultiplexer may further include: one or more extended layer symbol extractors, each configured to extract the extended layer signal by performing cancellation corresponding to previous layer data; one or more deinjection level controllers, each configured to increase the power of the extended layer signal to a level corresponding to the power reduced by the transmitter's injection level controller; and one or more extended layer BICM decoders configured to use the output signals of the one or more deinjection level controllers to recover one or more pieces of extended layer data.

[0354] according to Figure 8 As shown in the configuration, the signal demultiplexing method according to an embodiment of the present invention includes: generating a time-deinterleaved signal by applying time deinterleaving to a received signal; increasing the power of the received signal or the time-deinterleaved signal to a level corresponding to the power reduced by the power normalizer of the transmitter; recovering core layer data from the power-adjusted signal; extracting an enhancement layer signal by performing elimination corresponding to the core layer data on the power-adjusted signal; increasing the power of the enhancement layer signal to a level corresponding to the power reduced by the injection level controller of the transmitter; and using the enhancement layer signal to recover the enhancement layer data.

[0355] In this case, extracting the enhancement layer signal may involve receiving all codewords from the core layer LDPC decoder of the core layer BICM decoder and immediately performing bit interleaving on all codewords.

[0356] In this case, extracting the enhancement layer signal may include receiving information bits from the core layer LDPC decoder of the core layer BICM decoder, performing core layer LDPC encoding on the information bits, and then performing bit interleaving.

[0357] In this case, extracting the enhancement layer signal may include receiving information bits from the core layer BCH decoder of the core layer BICM decoder, performing core layer BCH encoding and core layer LDPC encoding on the information bits, and then performing bit interleaving.

[0358] Figure 9 It is shown Figure 8 A block diagram of an example of the core layer BICM decoder 520 and the enhancement layer symbol extractor 530 shown.

[0359] refer to Figure 9The core layer BICM decoder 520 includes a core layer symbol demapper, a core layer bit deinterleaver, a core layer LDPC decoder, and a core layer BCH decoder.

[0360] In other words, Figure 9 In the example shown, the core layer error correction decoder includes a core layer LDPC decoder and a core layer BCH decoder.

[0361] In addition, Figure 9 In the example shown, the core layer LDPC decoder provides all codewords, including the parity bits, to the enhancement layer symbol extractor 530. That is, although the LDPC decoder typically only outputs the information bits of all LDPC codewords, the LDPC decoder can output all codewords.

[0362] In this case, although the enhancement layer symbol extractor 530 can be easily implemented because it does not need to include the core layer LDPC encoder or the core layer BCH encoder, residuals may still be retained in the LDPC code parity check part.

[0363] Figure 10 It is shown Figure 8 A block diagram of yet another example of the core layer BICM decoder 520 and the enhancement layer symbol extractor 530 shown.

[0364] refer to Figure 10 The core layer BICM decoder 520 includes a core layer symbol demapper, a core layer bit deinterleaver, a core layer LDPC decoder, and a core layer BCH decoder.

[0365] In other words, Figure 10 In the example shown, the core layer error correction decoder includes a core layer LDPC decoder and a core layer BCH decoder.

[0366] In addition, Figure 10 In the example shown, the core layer LDPC decoder provides information bits, excluding parity bits, to the enhancement layer symbol extractor 530.

[0367] In this case, although the enhancement layer symbol extractor 530 does not need to include the core layer BCH encoder, it must include the core layer LDPC encoder.

[0368] Figure 10 The example shown can be larger than Figure 9 The example shown aims to eliminate residuals that might remain in the parity section of the LDPC code.

[0369] Figure 11 It is shown Figure 8A block diagram of yet another example of the core layer BICM decoder 520 and the enhancement layer symbol extractor 530 shown.

[0370] refer to Figure 11 The core layer BICM decoder 520 includes a core layer symbol demapper, a core layer bit deinterleaver, a core layer LDPC decoder, and a core layer BCH decoder.

[0371] In other words, Figure 11 In the example shown, the core layer error correction decoder includes a core layer LDPC decoder and a core layer BCH decoder.

[0372] exist Figure 11 In the example shown, the output of the core layer BCH decoder corresponding to the core layer data is provided to the enhancement layer symbol extractor 530.

[0373] In this case, although the enhancement layer symbol extractor 530 has high complexity because it must include both the core layer LDPC encoder and the core layer BCH encoder, it guarantees higher performance than... Figure 9 and 10 The example in [the example] shows higher performance.

[0374] Figure 12 It is shown Figure 1 The block diagram shows another example of a signal demultiplexer.

[0375] refer to Figure 12 According to an embodiment of the present invention, the signal demultiplexer includes a time deinterleaver 510, a denormalizer 1010, a core layer BICM decoder 520, an enhancement layer symbol extractor 530, an enhancement layer BICM decoder 540, one or more extended layer symbol extractors 650 and 670, one or more extended layer BICM decoders 660 and 680, and deinjection level controllers 1020, 1150, and 1170.

[0376] in this case, Figure 12 The signal demultiplexer shown can be used with Figure 7 This corresponds to the apparatus shown for generating broadcast signal frames.

[0377] The time deinterleaver 510 receives received signals from the OFDM receiver to perform operations such as synchronization, channel estimation, and equalization, and performs operations related to the distribution of burst errors occurring on the channel. In this case, L1 signaling information can first be decoded by the OFDM receiver and then used for data decoding. Specifically, the injection level information of the L1 signaling information can be transmitted to the denormalizer 1010 and the de-injection level controllers 1020, 1150, and 1170.

[0378] In this case, the denormalizer 1010 can obtain the injection level information of all layers, and the denormalization factor can be obtained using the following Equation 6. The input signal can then be multiplied by the denormalization factor:

[0379]

[0380] In other words, the denormalization factor is the reciprocal of the normalization factor expressed in Equation 4 above.

[0381] In one embodiment, when the N1 signaling includes not only injection level information but also normalization factor information, the denormalizer 1010 can easily obtain the denormalization factor by taking the reciprocal of the normalization factor, without needing to use the injection level to calculate the denormalization factor.

[0382] The denormalizer 1010 corresponds to the transmitter's power normalizer and increases the power level that the power normalizer has reduced.

[0383] Despite Figure 12 In the example shown, denormalizer 1010 is illustrated as adjusting the power of the output signal of time interleaver 510. However, in one embodiment, denormalizer 1010 may be located before time interleaver 510, such that power adjustment can be performed before interleaving.

[0384] In other words, the denormalizer 1010 can be considered to be located before or after the time interleaver 510, and amplifies the amplitude of the signal to achieve the purpose of LLR calculation of the core layer symbol demapper.

[0385] The output of the time deinterleaver 510 (or the output of the denormalizer 1010) is provided to the core layer BICM decoder 520, and the core layer BICM decoder 520 recovers the core layer data.

[0386] In this configuration, the core layer BICM decoder 520 includes a core layer symbol demapper, a core layer bit deinterleaver, and a core layer error correction decoder. The core layer symbol demapper calculates the symbol-related LLR value, the core layer bit deinterleaver strongly mixes the calculated LLR value with the burst error, and the core layer error correction decoder corrects errors occurring on the channel.

[0387] Specifically, the core layer error correction decoder can output only the information bits, or it can output all bits that have been combined with the parity bits. In this case, the core layer error correction decoder can output only the information bits as core layer data, and can output all bits that have been combined with the parity bits to the enhancement layer symbol extractor 530.

[0388] A core-layer error correction decoder can be formed by cascading a core-layer LDPC decoder and a core-layer BCH decoder. That is, the input to the core-layer error correction decoder can be fed into the core-layer LDPC decoder, the output of the core-layer LDPC decoder can be fed into the core-layer BCH decoder, and the output of the core-layer BCH decoder can become the output of the core-layer error correction decoder. In this configuration, the LDPC decoder performs LDPC decoding, and the BCH decoder performs BCH decoding.

[0389] An enhancement layer error correction decoder can also be formed by cascading the enhancement layer LDPC decoder and the enhancement layer BCH decoder. That is, the input of the enhancement layer error correction decoder can be input to the enhancement layer LDPC decoder, the output of the enhancement layer LDPC decoder can be input to the enhancement layer BCH decoder, and the output of the enhancement layer BCH decoder can become the output of the enhancement layer error correction decoder.

[0390] Alternatively, an extended layer error correction decoder can be formed by cascading an extended layer LDPC decoder and an extended layer BCH decoder. That is, the input to the extended layer error correction decoder can be fed into the extended layer LDPC decoder, the output of the extended layer LDPC decoder can be fed into the extended layer BCH decoder, and the output of the extended layer BCH decoder can become the output of the extended layer error correction decoder.

[0391] Specifically, it has been referenced Figure 9 , 10 The trade-off between complexity and performance described in section 11 regarding which of the outputs of the error correction decoder to use applies not only to... Figure 12 The core layer BICM decoder 520 and the enhancement layer symbol extractor 530 are also applicable to the extension layer symbol extractors 650 and 670 and the extension layer BICM decoders 660 and 680.

[0392] The enhancement layer symbol extractor 530 can receive all bits from the core layer BICM decoder 520 of the core layer error correction decoder, and can extract enhancement layer symbols from the output signal of the time deinterleaving unit 510 or the denormalizer 1010. In one embodiment, the enhancement layer symbol extractor 530 may not receive all bits from the error correction decoder of the core layer BICM decoder 520, but may instead receive LDPC information bits or BCH information bits.

[0393] In this configuration, the enhancement layer symbol extractor 530 includes a buffer, a subtractor, a core layer symbol mapper, and a core layer bit interleaver. The buffer stores the output signal of either the time deinterleaver 510 or the denormalizer 1010. The core layer bit interleaver receives all bits (information bits + parity bits) from the core layer BICM decoder and performs the same core layer bit interleaving as the transmitter. The core layer symbol mapper generates the same core layer symbols as the transmitter from the interleaved signal. The subtractor obtains the enhancement layer symbols by subtracting the output signal of the core layer symbol mapper from the signal stored in the buffer and transmits the enhancement layer symbols to the de-injection level controller 1020.

[0394] In this case, the core layer bit interleaver and core layer symbol mapper included in the enhancement layer symbol extractor 530 can be combined with... Figure 7 The core layer bit interleaver and core layer symbol mapper shown are the same.

[0395] The de-injection level controller 1020 receives the enhancement layer symbols and increases the power of the input signal to a level that the transmitter's injection level controller has already reduced the power of. In other words, the de-injection level controller 1020 amplifies the input signal and provides the amplified input signal to the enhancement layer BICM decoder 540.

[0396] The enhancement layer BICM decoder 540 receives enhancement layer symbols whose power is increased by the de-injection level controller 1020 and recovers the enhancement layer data.

[0397] In this configuration, the enhancement layer BICM decoder 540 may include an enhancement layer symbol demapper, an enhancement layer bit deinterleaver, and an enhancement layer error correction decoder. The enhancement layer symbol demapper calculates the LLR value associated with the enhancement layer symbols, the enhancement layer bit deinterleaver strongly mixes the calculated LLR value with burst errors, and the enhancement layer error correction decoder corrects errors occurring on the channel.

[0398] Specifically, the enhancement layer error correction decoder can output only the information bits, or it can output all bits that have been combined with the parity bits. In this case, the enhancement layer error correction decoder can output only the information bits as enhancement layer data, and it can output all bits that have been mixed with the parity bits to the extension layer symbol extractor 650.

[0399] The extended layer symbol extractor 650 receives all bits from the enhanced layer error correction decoder of the enhanced layer BICM decoder 540 and extracts the extended layer symbols from the output signal of the de-injection level controller 1020.

[0400] In this case, the de-injection level controller 1020 can amplify the power of the output signal of the subtractor of the enhancement layer symbol extractor 530.

[0401] In this configuration, the extended layer symbol extractor 650 includes a buffer, a subtractor, an enhancement layer symbol mapper, and an enhancement layer bit interleaver. The buffer stores the output signal of the injection level controller 1020. The enhancement layer bit interleaver receives all bits (information bits + parity bits) from the enhancement layer BICM decoder and performs the same enhancement layer bit interleaver as the transmitter. The enhancement layer symbol mapper generates enhancement layer symbols from the interleaved signal that are identical to the transmitter's enhancement layer symbols. The subtractor obtains the extended layer symbols by subtracting the output signal of the enhancement layer symbol mapper from the signal stored in the buffer and transmits the extended layer symbols to the extended layer BICM decoder 660.

[0402] In this case, the enhanced layer bit interleaver and enhanced layer symbol mapper included in the extended layer symbol extractor 650 can be combined with... Figure 7 The enhancement layer bit interleaver and enhancement layer symbol mapper shown are the same.

[0403] The injection level controller 1150 increases the power at the level of the corresponding layer of the transmitter where the injection level controller has reduced the power.

[0404] In this case, the de-injection level controller can be viewed as performing an operation that multiplies the extended layer gain by Equation 7 below. In this case, the 0th injection level can be considered as 0dB:

[0405]

[0406] The extended layer BICM decoder 660 receives extended layer symbols whose power is increased by the de-injection level controller 1150 and recovers the extended layer data.

[0407] In this configuration, the extended layer BICM decoder 660 may include an extended layer symbol demapper, an extended layer bit deinterleaver, and an extended layer error correction decoder. The extended layer symbol demapper calculates the LLR value associated with the extended layer symbols, the extended layer bit deinterleaver strongly mixes the calculated LLR value with the burst error, and the extended layer error correction decoder corrects errors occurring on the channel.

[0408] Specifically, if there are two or more extension layers, each of the extension layer symbol extractor and the extension layer BICM decoder can include two or more extractors or decoders.

[0409] In other words, Figure 12In the example shown, the extended layer error correction decoder of the extended layer BICM decoder 660 can output only the information bits, or it can output all bits that have been combined with the parity bits. In this case, the extended layer error correction decoder outputs only the information bits as extended layer data, and can output all bits that have been mixed with the parity bits to the subsequent extended layer symbol extractor 670.

[0410] Based on the configuration and operation of the extended layer symbol extractor 650, the extended layer BICM decoder 660, and the de-injection level controller 1150 described above, the configuration and operation of the extended layer symbol extractor 670, the extended layer BICM decoder 680, and the de-injection level controller 1170 can be easily understood.

[0411] Figure 12 The lower of the de-injection level controllers 1020, 1150, and 1170 shown can correspond to a greater power increase. That is, de-injection level controller 1150 can increase more power than de-injection level controller 1020, and de-injection level controller 1170 can increase more power than de-injection level controller 1150.

[0412] It can be seen that, Figure 12 The signal demultiplexer shown first recovers the core layer data, uses core layer symbol cancellation to recover the enhancement layer data, and uses enhancement layer symbol cancellation to recover the extension layer data. Two or more extension layers can be provided; in this case, recovery begins with the extension layer combined at higher power levels.

[0413] Figure 13 This is a diagram illustrating the power increase attributed to the combination of core layer signals and enhancement layer signals.

[0414] refer to Figure 13 As can be seen, when a multiplexed signal is generated by combining the core layer signal with the enhancement layer signal whose power injection level has been reduced, the power level of the multiplexed signal is higher than that of the core layer signal or the enhancement layer signal.

[0415] In this case, the voltage can be increased by a step size of 0.5 dB or 1 dB. Figure 3 and Figure 7 The injection level controller shown adjusts the injection level from 0dB to 25.0dB. When the injection level is 3.0dB, the power of the enhancement layer signal is 3dB lower than that of the core layer signal. When the injection level is 10.0dB, the power of the enhancement layer signal is 10dB lower than that of the core layer signal. This relationship can be applied not only between the core layer and enhancement layer signals, but also between the enhancement layer and extension layer signals, or even between extension layer signals.

[0416] Figure 3 and Figure 7 The power normalizer shown can adjust the power level after combination, thereby solving problems such as signal distortion that may be caused by the power increase attributable to combination.

[0417] Figure 14 This is an operation flowchart illustrating a method for generating broadcast signal frames according to an embodiment of the present invention.

[0418] refer to Figure 14 In the method according to an embodiment of the present invention, in step S1210, BICM is applied to the core layer data.

[0419] Furthermore, in the method according to an embodiment of the present invention, in step S1220, BICM is applied to the enhancement layer data.

[0420] The BICM applied in step S1220 may be different from the BICM applied in step S1210. In this case, the BICM applied in step S1220 may be less robust than the BICM applied in step S1210. In this case, the bit rate of the BICM applied in step S1220 may be less robust than the bit rate of the BICM applied in step S1210.

[0421] In this case, the enhancement layer signal can correspond to the enhancement layer data recovered based on the elimination corresponding to the recovery of the core layer data, where the core layer data corresponds to the core layer signal.

[0422] Furthermore, in the method according to an embodiment of the present invention, in step S1230, a power-reduced enhancement layer signal is generated by reducing the power of the enhancement layer signal.

[0423] In this case, in step S1230, the injection level can be changed from 00dB to 25.0dB in increments of 0.5dB or 1dB.

[0424] Furthermore, in the method according to an embodiment of the present invention, in step S1240, a multiplexed signal is generated by combining the core layer signal and the power-reduced enhancement layer signal.

[0425] In other words, in step S1240, the core layer signal and the enhancement layer signal are combined with different power levels, such that the power level of the enhancement layer signal is lower than the power level of the core layer signal.

[0426] In this case, in step S1240, one or more extended layer signals having a lower power level than the core layer signal and the enhancement layer signal can be combined with the core layer signal and the enhancement layer signal.

[0427] Furthermore, in the method according to an embodiment of the present invention, in step S1250, the power of the multiplexed signal is reduced.

[0428] In this case, in step S1250, the power of the multiplexed signal can be reduced to the power of the core layer signal. In this case, in step S1250, the power of the multiplexed signal can be reduced to the level of the power already increased in step S1240.

[0429] Furthermore, in the method according to an embodiment of the present invention, in step S1260, a time-interleaved signal is generated by performing time interleaving applied to both the core layer signal and the enhancement layer signal.

[0430] In this case, step S1260 can use one of the time-interleaved groups, and the boundary between the time-interleaved groups can be the boundary between the physical layer channels (PLPs) of the core layer corresponding to the core layer signal.

[0431] In this case, step S1260 can use a hybrid time interleaver to perform interleaving. In this case, the physical layer channels (PLPs) of the core layer and enhancement layer can consist of only complete FEC blocks.

[0432] In this case, step S1260 can use a convolutional temporal interleaver to perform interleaving. The temporal interleaver group can include a physical layer channel (PLP) containing incomplete FEC blocks, and a preamble can be used to signal the start position information of the first complete FEC block in the physical layer channel (PLP).

[0433] In this case, step S1260 can be performed by using one of the multiple operating modes.

[0434] In this case, the operating modes may include a first mode corresponding to no temporal interleaving, a second mode for performing convolutional temporal interleaving, and a third mode for performing mixed temporal interleaving.

[0435] Furthermore, in the method according to an embodiment of the present invention, in step S1270, a broadcast signal frame is generated including a preamble for transmitting time interleaver information corresponding to the interleaving.

[0436] In this case, time-interleaved information can be sent using signals based on the core layer.

[0437] In this case, where the boundary between time-interleaved packets does not correspond to the boundary between FEC blocks of the enhancement layer, a preamble can be used to signal information for identifying a portion of the FEC block of the enhancement layer, where the FEC block corresponds to the boundary between time-interleaved packets.

[0438] In this case, the information used to identify a portion of the FEC block may include at least one of the following: the start position information of the physical layer channel (PLP) in the core layer, the start position information of the physical layer channel (PLP) in the enhancement layer, the modulation information corresponding to the enhancement layer, and the FEC type information corresponding to the enhancement layer.

[0439] In this case, the start position information of the physical layer channel (PLP) can correspond to the index of the first data unit of the physical layer channel (PLP).

[0440] In this case, modulation information can only be sent using a signal if the FEC type information meets the predetermined conditions.

[0441] In this case, the enhancement layer signal corresponds to the enhancement layer data that can be recovered based on the elimination corresponding to the recovery of the core layer data, where the core layer data corresponds to the core layer signal.

[0442] In this case, step S1270 may include: generating a preamble; generating a preamble; and generating a superimposed payload corresponding to the time-interleaved signal.

[0443] In this case, the preamble may include PLP identification information for identifying the physical layer channel (PLP); and layer identification information for identifying the layer corresponding to the layer.

[0444] In this case, PLP identification information and layer identification information can be included in the preamble as distinct fields.

[0445] In this case, based on the result of comparing the layer identification information with a predetermined value (IF(j>0)), the time interleaver information can be selectively included in the preamble for each physical layer channel (PLP).

[0446] In this case, based on the result of comparing the layer identification information with a predetermined value (IF(j>0)), the preamble can selectively include injection level information corresponding to the injection level controller for each physical layer channel (PLP).

[0447] In this case, the preamble can be shorter than the preamble and has a fixed length.

[0448] In this case, the preamble may include symbols representing the structure of the preamble, wherein the symbols correspond to a fixed-length bit string representing a combination of modulation scheme / coding rate, FFT size, guard interval length, and pilot pattern of the preamble.

[0449] In this case, the symbol can correspond to a lookup table, in which a preamble structure corresponding to the second FFT size is assigned before the preamble structure corresponding to the first FFT size. When the modulation scheme / coding rate is the same, the second FFT size is smaller than the first FFT size. Furthermore, a preamble structure corresponding to the second guard interval length is assigned before the preamble structure corresponding to the first guard interval length. When the modulation scheme / coding rate is the same and the FFT size is the same, the second guard interval length is longer than the first guard interval length.

[0450] In this case, the broadcast signal frame can be an ATSC 3.0 frame.

[0451] In this case, L1 signaling information may include injection level information and / or normalization factor information.

[0452] In this case, the preamble can include physical layer channel type information, start position information, and size information.

[0453] In this case, type information can be used to identify one of the first type corresponding to non-distributed physical layer channels and the second type corresponding to distributed physical layer channels.

[0454] In this case, non-distributed physical layer channels can be assigned to continuous data unit indexes, and distributed physical layer channels can include two or more sub-slices.

[0455] In this case, for each physical layer channel (PLP), type information can be selectively transmitted by signal based on the comparison result between the layer identification information and a predetermined value.

[0456] In this case, type information can be sent via signals only to the core layer.

[0457] In this case, the starting position information can be the same as the index of the first data unit corresponding to the physical layer channel.

[0458] In this case, the start location information can be indicated by the cell addressing scheme to indicate the start location of the physical layer channel.

[0459] In this case, the start position information can be included in the preamble for each physical layer channel (PLP) without checking the conditions of the conditional statement corresponding to the layer identification information.

[0460] In this case, size information can be generated based on the number of data units allocated to the physical layer channel.

[0461] In this case, size information can be included in the preamble used for each physical layer channel (PLP) without checking the conditions of the conditional statement corresponding to the layer identification information.

[0462] In this case, the preamble may include a field indicating the start position of the first complete FEC block for the first and second modes corresponding to the current physical layer channel, but may not include a field indicating the start position of the first FEC block for the third mode.

[0463] In this case, the field indicating the start position of the first FEC block can be one of the first field used in the first mode and the second field used in the second mode, and the first field and the second field can have different lengths.

[0464] In this case, the length of the second field can be longer than the length of the first field.

[0465] In this case, the length of the first field can be determined based on the length of the LDPC codeword and the modulation order, and the length of the second field can be determined not only by the length of the LDPC codeword and the modulation order but also by further considering the depth of the convolutional time interleaver.

[0466] In this case, the length of the first field can be 15 bits, and the length of the second field can be 22 bits.

[0467] In this case, for each of the core layer corresponding to the core layer signal and the enhancement layer corresponding to the enhancement layer signal, the first field and the second field can be sent by signal respectively.

[0468] In this case, the preamble may include a field indicating the start position of the first complete FEC block corresponding to each physical layer channel in the physical layer channel.

[0469] In this case, the start position of the first complete FEC block can be specified relative to the first unit of each physical layer channel in the physical layer channel.

[0470] In this case, when interleaving corresponds to convolutional time interleaving, the start position of the first complete FEC block can indicate the first cell of the first complete FEC block before convolutional time interleaving, and the position of the first cell of the first complete FEC block can be signaled after convolutional time interleaving.

[0471] In this case, the field indicating the start position of the first complete FEC block can correspond to the position after convolutional temporal interleaving, where the position after convolutional temporal interleaving is calculated by adding the position (C) before convolutional temporal interleaving and the delay caused by convolutional temporal interleaving.

[0472] In this case, the latency caused by convolutional temporal interleaving can be calculated by using the position (L1D_plp_CTI_start_row) of the interleaving selector corresponding to the convolutional temporal interleaving.

[0473] In this case, the delay caused by convolutional temporal interleaving can be calculated by using the modulo operation of the sum of the position of the interleaver selector corresponding to convolutional temporal interleaving and the position before convolutional temporal interleaving (L1D_plp_CTI_start_row+C) and the number of delay lines (N_row) corresponding to convolutional temporal interleaving.

[0474] In this case, the location of the signal transmission interleaver selector can be used only for the core layer physical layer channel corresponding to the core layer, and the location of the signal transmission interleaver selector can be omitted for the enhancement layer physical layer channel corresponding to the enhancement layer.

[0475] In this case, the position of the interleaver selector for the enhancement layer physical layer channel can be calculated by using the position of the interleaver selector that is signaled for the core layer physical layer channel corresponding to the enhancement layer physical layer channel.

[0476] In this case, the field indicating the start position of the first complete FEC block can be 22 bits long.

[0477] In this case, a field indicating the start position of the first complete FEC block can be sent by signaling for each of the core layer physical layer channel and the enhancement layer physical layer channel.

[0478] Despite Figure 14 While not explicitly shown, the method may further include a step of generating signaling information that includes the injection level information corresponding to step S1230. In this case, the signaling information may be L1 signaling information.

[0479] Figure 14 The method for generating broadcast signal frames shown can be compared with... Figure 2 The step S210 shown corresponds to this.

[0480] Figure 15 This is a diagram illustrating the structure of a superframe including broadcast signal frames according to an embodiment of the present invention.

[0481] refer to Figure 15The superframe based on Layer Distributed Multiplexing (LDM) is configured with at least one frame, and each frame is configured with at least one OFDM symbol.

[0482] In this case, each OFDM symbol may begin with at least one preamble symbol. Furthermore, the frame may include reference symbols or pilot symbols.

[0483] Figure 15 The superframe 1510 illustrated may include an LDM frame 1520, a single-layer frame 1530 without LDM, and a future extension frame (FEF) 1540 for future scalability, and can be configured using time division multiplexing (TDM).

[0484] When two layers are applied, LDM frame 1520 may include upper layer (UL) 1553 and lower layer (LL) 1555.

[0485] In this case, the upper layer 1553 can correspond to the core layer, and the lower layer 1555 can correspond to the enhancement layer.

[0486] In this case, the LDM frame 1520, which includes the upper layer 1553 and the lower layer 1555, can be the preamble 1552 and the preamble 1551.

[0487] In this scenario, upper-layer and lower-layer data can share a time interleaver to reduce complexity and memory size, and can use the same frame length and FFT size.

[0488] Furthermore, a single-layer frame 1530 may include a preamble 1562 and a preamble 1561.

[0489] In this scenario, single-layer frame 1530 can use a different FFT size, temporal interleaver, and frame length than LDM frame 1520. In this case, single-layer frame 1530 and LDM frame 1520 can be multiplexed in superframe 1510 based on the TDM scheme.

[0490] Figure 16 This is a diagram illustrating an example of an LDM frame using multiple physical layer channels and two layers of LDM.

[0491] refer to Figure 16 An LDM frame begins with a preamble signal that includes system version information or general signaling information. An L1 signaling signal that includes information such as coding rate, modulation information, and the number of physical layer channels can follow the preamble as a preamble.

[0492] A burst-form common physical layer channel (PLP) can be transmitted following a preamble (L1 signal). In this case, the common physical layer channel can transmit data that can be shared with other physical layer channels in the frame.

[0493] A two-layer LDM scheme can be used to transmit multi-physical layer channels for serving different broadcast signals. In this case, services requiring robust reception performance, such as indoor / mobile (720p or 1080p HD, etc.), can use the core layer (upper layer) data physical layer channel. In this case, fixed reception services requiring high transmission rates (4K-UHD or multi-HD, etc.) can use the enhancement layer (lower layer) data physical layer channel.

[0494] If multiple physical layer channels are multiplexed, it can be seen that the total number of physical layer channels increases.

[0495] In this scenario, the core layer data-physical layer channels and the enhancement layer data-physical layer channels can share a time interleaver to reduce complexity and memory size. Alternatively, the core layer data-physical layer channels and the enhancement layer data-physical layer channels can have the same physical layer channel size (PLP size) or different physical layer channel sizes.

[0496] According to an embodiment, the layered PLPs may have different PLP sizes from each other, and information for identifying the start position of the PLP or information for identifying the size of the PLP may be sent by signal.

[0497] Figure 17 This is a diagram illustrating yet another example of an LDM frame using multiple physical layer channels and two-layer LDM.

[0498] refer to Figure 17 An LDM frame may include a common physical layer channel following a preamble and L1 signal. A dual-layer LDM scheme can be used to transmit the core layer data physical layer channel and the enhancement layer data physical layer channel after the common physical layer channel.

[0499] Specifically, Figure 17 The core layer data-physical layer channel and the enhancement layer data-physical layer channel can correspond to one of type 1 and type 2. Type 1 and type 2 can be defined as follows:

[0500] –Type 1 PLP

[0501] If a common PLP exists, it is transmitted after the common PLP.

[0502] It is transmitted in bursts (a piece) within a frame.

[0503] –Type 2 PLP

[0504] If a Type 1 PLP exists, it is transmitted after the Type 1 PLP.

[0505] It is transmitted in the form of two or more sub-fragments within a frame.

[0506] Time diversity and power consumption increase with the number of sub-slices.

[0507] In this scenario, a Type 1 PLP can correspond to a non-distributed PLP, and a Type 2 PLP can correspond to a distributed PLP. In this case, non-distributed PLPs can be assigned for continuous data unit indexing. In this case, distributed PLPs can be assigned to two or more sub-slices.

[0508] Figure 18 This is a diagram illustrating an application example of an LDM frame using multiple physical layer channels and a two-layer LDM.

[0509] refer to Figure 18 In an LDM frame, the common physical layer channel (PLP(1,1)) can be included after the preamble and header. A time-division scheme can be used to include the data physical layer channel (PLP(2,1)) used for robust audio services in the LDM frame.

[0510] Furthermore, a two-layer LDM scheme can be used to transmit the core layer data physical layer channel (PLP(3,1)) for mobile / indoor services (720p or 1080p HD) and the enhancement layer data physical layer channel (PLP(3,2)) for high data rate services (4K-UHD or multi-HD).

[0511] Figure 19 This is a diagram illustrating yet another application example of an LDM frame using multiple physical layer channels and two layers of LDM.

[0512] refer to Figure 19 An LDM frame may include a preamble, a common physical layer channel (PLP(1,1)). In this case, the core layer physical layer channel (PLP(2,1), PLP(3,1)) can be used to deliver robust audio services and mobile / indoor services (720p or 1080p HD), and the enhancement layer physical layer channel (PLP(2,2), PLP(3,2)) can be used to deliver high data rate services (4K-UHD or multiple HD).

[0513] In this scenario, the core layer data physical layer channel and the enhancement layer data physical layer channel can use the same time interleaver.

[0514] In this case, the physical layer channels (PLP(2,2), PLP(3,2)) that provide the same service can be identified by using the PLP_GROUP_ID that indicates the same PLP group.

[0515] According to an embodiment, when using physical layer channels with different sizes for different LDM layers, the service can be identified by the start position and size of each physical layer channel instead of using PLP_GROUP_ID.

[0516] Despite Figure 18 and Figure 19 In this process, multiple physical layer channels and layers corresponding to layer multiplexing are identified through PLP(i,j), but the PLP identification information and layer identification information can be sent as different fields using signals.

[0517] According to an embodiment, different layers can use PLPs of different sizes. In this case, a PLP identifier can be used to identify each service.

[0518] When PLPs of different sizes are used for different layers, the start position and size of the PLP can be sent as signals for each PLP.

[0519] The following pseudocode is used to illustrate an example of a field included in a preamble according to an embodiment of the present invention. The L1 signaling information of the preamble may include the following pseudocode.

[0520] [Pseudocode]

[0521]

[0522]

[0523]

[0524] NUM_LAYER can correspond to two or three bits in the pseudocode described above. In this case, NUM_LAYER can be a field used to identify the number of layers in each time-divided PLP. In this case, NUM_LAYER can be defined in the NUM_PLP loop so that the number of layers can be different for each time-divided PLP.

[0525] LL_INJECTION_LEVEL can correspond to 3 to 8 bits. In this case, LL_INJECTION_LEVEL can be a field used to identify the injection level of the lower layer (enhancement layer).

[0526] In this case, LL_INJECTION_LEVEL can correspond to the injected level information.

[0527] In this case, when the number of layers is 2 or more, LL_INJECTION_LEVEL can be defined from the second layer (j>0).

[0528] Fields such as PLP_ID(I,j), PLP_GROUP_ID, PLP_TYPE, PLP_PAYLOAD_TYPE, PLP_CDO, PLP_MOD, PLP_SSD, PLP_FEC_TYPE, PLP_NUM_BLOCKS_MAX, IN_BAND_A_FLAG, IN_BAND_B_FLAG, PLP_MODE, STATIC_PADDING_FLAG, etc., can correspond to parameters defined for each layer and can be defined inside the NUM_LAYER loop.

[0529] In this case, PLP_ID(i,j) can correspond to both PLP identification information and layer identification information. For example, "i" in PLP_ID(i,j) can correspond to PLP identification information, and "j" in PLP_ID(i,j) can correspond to layer identification information.

[0530] According to an embodiment, PLP identification information and layer identification information can be included in the preamble as distinct fields.

[0531] In addition, time interleaver information such as TIME_IL_LENGTH and TIME_IL_TYPE, FRAME_INTERVAL related to the PLP size, and fields such as FF_FLAG, FIRST_RF_IDX, FIRST_FRAME_IDX, RESERVED_1, and STATIC_FLAG can be defined outside the NUM_LAYER loop and inside the NUM_PLP loop.

[0532] Specifically, PLP_TYPE corresponds to the type information of the physical layer channel and can correspond to 1 bit used to identify one of the two types, Type 1 and Type 2. Although PLP_TYPE is included in the preamble without checking the condition of the conditional statement corresponding to the layer identification information (j) in the pseudocode above, PLP_TYPE can be selectively sent by signal (only for the core layer) based on the result of comparing the layer identification information (j) with a predetermined value (0) (if (j = 0)).

[0533] Although PLP_TYPE is defined in the NUM_LAYER loop in the pseudocode above, PLP_TYPE can also be defined outside the NUM_LAYER loop and inside the NUM_PLP loop.

[0534] In the pseudocode above, PLP_START corresponds to the start position of the corresponding physical layer channel. In this case, PLP_START can use a cell addressing scheme to identify the start position. In this case, PLP_START can be the index of the first data unit corresponding to the corresponding PLP.

[0535] Specifically, PLP_START can be sent as a signal for each physical layer channel, and the PLP_START can be used to identify the service by using multiple physical layer channels and a field for the size of the PLP sent as a signal.

[0536] In the pseudocode above, PLP_SIZE corresponds to the size information of the physical layer channel. In this case, PLP_SIZE can be the same as the number of data units allocated to the corresponding physical layer channel.

[0537] In other words, PLP_TYPE can be sent using signals based on layer identification information, and PLP_START and PLP_SIZE can be sent using signals for each physical layer channel without considering layer identification information.

[0538] Figure 3 and Figure 7 The combinedr 340 shown functions to combine core layer signals and enhancement layer signals, and can perform the combination on the basis of a time-interleaved group shared by the core layer signals and enhancement layer signals, because the core layer signals and enhancement layer signals share a time-interleaved group.

[0539] In this case, time interleaver groups can be configured based on memory efficiency and system efficiency, using the core layer as the basis.

[0540] However, when setting up time-interleaver groups based on the core layer, there may be FEC blocks that are divided by time-interleaver group boundaries in the enhancement layer. If such divided FEC blocks exist, it may be necessary to signal a field to identify a portion of the FEC block corresponding to the time-interleaver group boundary.

[0541] The temporal interleaver used for layer demultiplexing can be a convolutional temporal interleaver (CTI) or a hybrid temporal interleaver (HTI). In this case, a convolutional temporal interleaver or a hybrid temporal interleaver can be used when there is one physical layer channel in the core layer, and a hybrid temporal interleaver can be used when there are two or more physical layer channels in the core layer. When using a hybrid temporal interleaver, the physical layer channel can consist only of a complete FEC block.

[0542] Figure 20 This is a diagram illustrating an example of using a convolutional temporal interleaver.

[0543] refer to Figure 20 The subframe consists of two layers: the core layer and the enhancement layer.

[0544] Because in Figure 20 In the example shown, the subframe includes only one physical layer channel (PLP#0) in the core layer, so the temporal interleaver corresponding to this subframe can be a convolutional temporal interleaver or a hybrid temporal interleaver, and the example shown corresponds to an example using a convolutional temporal interleaver. When using a convolutional temporal interleaver, the physical layer channels in each layer may include incomplete FEC blocks.

[0545] Such incomplete FEC blocks are located at the edge of the PLP and can be identified using fields such as "L1D_plp_CTI_fec_block_start", which indicates the location of the first complete FEC block in each PLP.

[0546] exist Figure 20 In the example shown, the physical layer channel (PLP#0) of the core layer and the physical layer channel (PLP#1) of the enhancement layer have the same starting position and size.

[0547] exist Figure 20 In the example shown, it can be seen that the time interleaver group (TI group) corresponds to the physical layer channel (PLP#0) of the core layer. The time interleaver group is applied together to the core layer and the enhancement layer, and is advantageous in terms of memory and system efficiency in relation to the core layer settings.

[0548] Figure 21 This is a diagram illustrating yet another example of using a convolutional temporal interleaver.

[0549] refer to Figure 21 As can be seen, the starting position and size of the core layer physical layer channel (PLP#0) and the enhancement layer physical layer channel (PLP#1) are different.

[0550] If the starting position and size of the core layer physical layer channel (PLP#0) and the starting position and size of the enhancement layer physical layer channel (PLP#1) are different from each other, an empty area can be included in the enhancement layer.

[0551] like Figure 21 As shown, when a clear region is included at the end of the enhancement layer physical layer channel (PLP#1), the enhancement layer physical layer channel (PLP#1) ends with a complete FEC block.

[0552] Figure 22 This is a diagram illustrating an example of using a hybrid time interleaver.

[0553] refer to Figure 22The core layer includes two physical layer channels (PLP#0, PLP#1).

[0554] Therefore, when the core layer consists of multiple physical layer channels, a hybrid time interleaver is used.

[0555] When using a hybrid time interleaver, all physical layer channels in the core and enhancement layers consist of only the complete FEC block.

[0556] In this case, some parts of the enhancement layer can be cleared to align with the core layer boundary.

[0557] Figure 23 It is shown Figure 22 The example shows a diagram of time interleaver grouping.

[0558] refer to Figure 23 As can be seen, the boundaries of the time interleaver grouping are set according to the boundaries of the physical layer channels corresponding to the core layer.

[0559] Although time interleaver groups include Figure 23 One of the core layer physical layer channels; however, according to one embodiment, the time interleaver group may include two or more core layer physical channels.

[0560] exist Figure 23 In the example shown, an FEC block of the enhancement layer can be divided by the time interleaver group boundary.

[0561] This is because the time interleaver group segmentation is performed on a core layer basis. In this case, it is possible to send information by signaling to identify incomplete FEC blocks in the enhancement layer, where the incomplete FEC blocks correspond to the time interleaver group boundaries.

[0562] Figures 24 to 26 This shows the calculation. Figure 23 The example shows the processing of the size of the incomplete FEC block.

[0563] refer to Figure 24 The start position of the enhancement layer physical layer channel (L1D_plp_start(PLP#0)), the size of the core layer physical layer channel (L1D_plp_size(PLP#0)), and the start position of the enhancement layer physical layer channel (L1D_plp_start(PLP#2)) are used to calculate the distance (A) between the start position of the enhancement layer physical layer channel (L1D_plp_start(PLP#2)) and the time interleaver group boundary.

[0564] refer to Figure 25The FEC block size of the enhancement layer is used to calculate the distance (B) between the starting position of the divided FEC block and the time interleaver grouping boundary.

[0565] In this case, the FEC block size can be determined by using the modulation information (L1D_plp_mod) corresponding to the enhancement layer and the FEC type information (L1D_plp_fec_type) corresponding to the enhancement layer.

[0566] refer to Figure 26 The portion (C) of the FEC block of the enhancement layer corresponding to the boundary between time interleaving groups is identified.

[0567] Table 3 below shows an example of the L1-details field of the preamble according to an embodiment of the present invention.

[0568] The preamble according to an embodiment of the present invention may include L1-basic and L1-detail.

[0569] Table 3

[0570]

[0571]

[0572]

[0573]

[0574]

[0575] All fields corresponding to the allocated bits in Table 3 can correspond to the most significant bit first (uimsbf) format of an unsigned integer.

[0576] In the fields of Table 3, L1D_plp_layer can be a field representing the layer corresponding to each physical layer channel. L1D_plp_start can correspond to the start position information of the current PLP and can indicate the index of the first data unit of the current PLP. L1D_plp_size can correspond to the size information of the current PLP and can indicate the number of data units allocated to the current PLP.

[0577] L1D_plp_fec_type can correspond to the FEC type information of the current PLP and can indicate the forward error correction (FEC) method used to encode the current PLP.

[0578] For example, L1D_plp_fec_type="0000" can correspond to BCH and 16200LDPC, L1D_plp_fec_type="0001" can correspond to BCH and 64800LDPC, L1D_plp_fec_type="0010" can correspond to CRC and 16200LDPC, L1D_plp_fec_type="0011" can correspond to CRC and 64800LDPC, L1D_plp_fec_type="0100" can correspond to 16200LDPC, and L1D_plp_fec_type="0101" can correspond to 64800LDPC.

[0579] L1D_plp_mod can indicate the modulation information of the current PLP. In this case, L1D_plp_mod can only be sent as a signal if L1D_plp_fec_type meets the predetermined conditions shown in Table 3.

[0580] For example, L1D_plp_mod="0000" can correspond to QPSK, L1D_plp_mod="0001" can correspond to 16QAM-NUC, L1D_plp_mod="0010" can correspond to 64QAM-NUC, L1D_plp_mod="0011" can correspond to 256QAM-NUC, L1D_plp_mod="0100" can correspond to 1024QAM-NUC, and L1D_plp_mod="0101" can correspond to 4096QAM-NUC. In this case, L1D_plp_mod can only be set to "0100" or "0101" when L1D_plp_fec_type corresponds to 64800LDPC.

[0581] L1D_plp_TI_mode indicates the time interleaving mode of PLP.

[0582] For example, L1D_plp_TI_mode="00" can represent a non-temporally interleaved mode, L1D_plp_TI_mode="01" can represent a convolutional temporally interleaved mode, and L1D_plp_TI_mode="10" can represent a mixed temporally interleaved mode.

[0583] L1D_plp_fec_block_start corresponds to the start position information of the first complete FEC block in the physical layer channel. L1D_plp_fec_block_start can only be sent as a signal when L1D_plp_TI_mode = "00".

[0584] When using layer multiplexing, since the starting position of the first FEC block in each layer can be different, L1D_plp_fec_block_start can be sent separately for each layer.

[0585] L1D_plp_CTI_fec_block_start corresponds to the start position information of the first complete block in the physical layer channel. L1D_plp_CTI_fec_block_start can only be sent as a signal when L1D_plp_TI_mode = "01".

[0586] In this case, more bits can be allocated to L1D_plp_CTI_fec_block_start than to L1D_plp_fec_block_start.

[0587] As mentioned above, when L1D_plp_TI_mode = "10", all PLPs only include the complete FEC block, so there is no need to send the start position of the first FEC block separately with a signal.

[0588] L1D_plp_HTI_num_fec_blocks can correspond to the number of FEC blocks contained in the current interleaved frame for the physical layer channel used in the core layer.

[0589] In this case, it can be seen that when L1D_plp_layer is 0 (core layer), each of the fields corresponding to convolutional temporal interleaving (L1D_plp_CTI_depth, L1D_plp_CTI_start_row) and the fields corresponding to hybrid temporal interleaving (L1D_plp_HTI_inter_subframe, L1D_plp_HTI_num_ti_blocks, L1D_plp_HTI_num_fec_blocks_max, L1D_plp_HTI_num_fec_blocks, L1D_plp_HTI_cell_interleaver, etc.) can be sent as temporal interleaving information as signals, depending on whether L1D_plp_TI_mode is 01 or 10.

[0590] In this case, L1D_plp_CTI_depth can indicate the number of rows used in the convolutional temporal interleaver, and L1D_plp_CTI_start_row can indicate the position of the interleaver selector at the beginning of the subframe.

[0591] In this case, L1D_plp_HTI_inter_subframe can indicate the mixed temporal interleaving mode, and L1D_plp_HTI_num_ti_blocks can indicate the number of TI blocks per interleaved frame or the number of subframes carrying cells from a TI block, and L1D_plp_HTI_num_fec_blocks_max can indicate a number of 1s less than the maximum number of FEC blocks per interleaved frame for the current physical layer channel, and L1D_plp_HTI_num_fec_blocks can indicate a number of 1s less than the number of FEC blocks included in the current interleaved frame for the current physical layer channel, and L1D_plp_HTI_cell_interleaver can indicate whether a cell interleaver is used.

[0592] In this case, time-interleaver information based on the core layer can be signaled separately from fields such as L1D_plp_TI_mode.

[0593] Figure 27 This is a diagram used to explain the number of bits required for L1D_plp_fec_block_start when L1D_plp_TI_mode = "00".

[0594] refer to Figure 27 It can be seen that when L1D_plp_TI_mode = "00" (no time interleaving), the cell address (C_in) of the FEC block start position before time interleaving and the cell address (C_out) of the FEC block start position after time interleaving are the same.

[0595] In the absence of time interweaving, such as Figure 27 As shown, convolutional interleaving is performed at a depth of 0.

[0596] In this case, L1D_plp_fec_block_start is defined after time interleaving, so that C_out can be sent as a signal for L1D_plp_fec_block_start for each physical layer channel in the subframe.

[0597] When the LDPC codeword is 16200 or 64800 and the modulation order is 2, 4, 6, 8, 10 and 12, the longest FEC block can have a length of 64800 / 2 = 32400.

[0598] Since 32400 can be represented by 15 bits, allocating 15 bits to L1D_plp_fec_block_start can cover the case where L1D_plp_TI_mode = "00".

[0599] Figure 28 and 29 This is a diagram used to explain the number of bits required for L1D_plp_CTI_fec_block_start when L1D_plp_TI_mode = "01".

[0600] refer to Figure 28 As can be seen, when L1D_plp_TI_mode = "01" (convolutional temporal interleaving), the cell address (C_in) of the FEC block start position before temporal interleaving and the cell address (C_out) of the FEC block start position after temporal interleaving are different due to interleaving.

[0601] In this case, L1D_plp_CTI_fec_block_start is defined after time interleaving, so that C_out can be sent as a signal for L1D_plp_CTI_fec_block_start for each physical layer channel in the subframe.

[0602] refer to Figure 29 As can be seen, the convolutional temporal interleaver with a depth of 4 operates with C_in as input and C_out as output.

[0603] In this case, given the input, 0 corresponds to line 0, 1 to line 1, 2 to line 2, 3 to line 3, 4 to line 0, 5 to line 1, 6 to line 2, 7 to line 3, 8 to line 0, 9 to line 1, and 10 to line 2.

[0604] First, output the numbers 0, 4, 8, etc. corresponding to the 0th row without delay.

[0605] The four delayed outputs correspond to the numbers 1, 5, 9, etc. in the first row.

[0606] The 8 delayed outputs correspond to 2, 6, 10, etc. in the second row.

[0607] The 12 delayed outputs correspond to the numbers 3, 7, etc. in the 3rd row.

[0608] In other words, it can be seen that for the nth row, there are (n×4) delays.

[0609] Despite Figure 29 The example given is a depth of 4 (the number of rows in the time interleaver is 4), but when the number of rows (the number of delay lines) corresponding to the time interleaver is N_row, the input corresponding to the nth row is delayed (n×N_row).

[0610] In this scenario, the cell address (L1D_plp_CTI_fec_block_start) at the start of the FEC block after time interleaving can be calculated as (C_in + (n × N_row)). Here, n is the row corresponding to C_in and can be determined from L1D_CTI_start_row in the time interleaving information transmitted via L1-details signaling. In this case, n can be ((L1D_CTI_start_row + C_in) % N_row). In this case, L1D_CTI_start_row can indicate the position of the interleaving selector at the beginning of the subframe.

[0611] In other words, L1D_plp_CTI_fec_block_start can be calculated by adding the delay caused by time interleaving to C_in.

[0612] To calculate the number of bits required to signal L1D_plp_CTI_fec_block_start, the maximum value of L1D_plp_CTI_fec_block_start is needed. As shown above, in the case of non-spread interleaving, the maximum value of C_in is (32400-1), the maximum value of n is N_row-1, and N_row can be at most 1024. In this case, the maximum value of L1D_plp_CTI_fec_block_start is ((32400-1)+(1024-1)×1024)=1079951. At least 21 bits can be used to signal 1079951.

[0613] In the case of extended interleaving, N_row can be up to 1448. In this case, the maximum value of L1D_plp_CTI_fec_block_start is ((32400-1)+(1448-1)×1448)=2127655. At least 22 bits can be used to send 2127655 as a signal.

[0614] Therefore, since the maximum value of L1D_plp_fec_block_start is the same as the maximum value of C_in when L1D_plp_TI_mode = "00", and the maximum value of L1D_plp_CTI_fec_block_start is the sum of the maximum value of C_in and the delay caused by interleaving when L1D_plp_TI_mode = "01", efficient signaling is possible when the number of bits used to signal L1D_plp_CTI_fec_block_start is greater than the number of bits used to signal L1D_plp_fec_block_start.

[0615] Since all physical layer channels in the core and enhancement layers consist of only complete FEC blocks when L1D_plp_TI_mode = "10", the start position of all physical layer channels becomes the start position of the first complete FEC block, thus eliminating the need to signal fields such as L1D_plp_fec_block_start or L1D_plp_CTI_fec_block_start.

[0616] Figure 30 This is a diagram showing an example of L1D_plp_fec_block_start for the enhancement layer.

[0617] Reference Figure 30 The starting position of the first complete FEC block used for the enhancement layer physical layer channel (enhancement PLP#2) exceeds the length of the enhancement layer physical layer channel (enhancement PLP#1).

[0618] like Figure 30 As shown in the example, if the start position of the first complete FEC block for the enhancement layer physical layer channel is specified relative to the first cell of the core layer physical layer channel, the start position of the first complete FEC block (L1D_plp_CTI_fec_block_start) may not be sent via a 22-bit signal.

[0619] In other words, Figure 30In the example, because the L1D_plp_CTI_fec_block_start of the enhancement layer physical layer channel (enhanced PLP#2) is the distance from the start position of the core layer physical layer channel (core PLP#0), the L1D_plp_CTI_fec_block_start of the enhancement layer physical layer channel (enhanced PLP#2) is greater than the plp_size of the enhancement layer physical layer channel (enhanced PLP#1). In this case, because plp_size is a 24-bit field, the L1D_plp_CTI_fec_block_start of the enhancement layer physical layer channel (enhanced PLP#2) cannot be represented by 22 bits.

[0620] Therefore, preferably, L1D_plp_CTI_fec_block_start or L1D_plp_fec_block_start is determined as the distance from the first unit of the corresponding PLP. Specifically, preferably, L1D_plp_CTI_fec_block_start or L1D_plp_fec_block_start for the enhancement layer physical layer channel is not the distance from the first unit of the corresponding core layer physical layer channel, but rather the distance from the first unit of the corresponding (current) physical layer channel (enhancement layer physical layer channel).

[0621] L1D_plp_CTI_fec_block_start indicates the position of the first cell of the first complete FEC block before Convolutional Temporal Interleaving (CTI) for the current physical layer channel in the current subframe or a subsequent subframe, after CTI. This position in the current subframe can be specified relative to the first cell of the current physical layer channel leaving the CTI interleaver, where the CTI selector is located at position L1D_plp_CTI_start_row. L1D_plp_CTI_fec_block_start can extend beyond the subframe boundary, thus indicating a position in the physical layer channel data belonging to a subsequent subframe. L1D_plp_CTI_fec_block_start can be determined before cell multiplexing.

[0622] L1D_plp_CTI_fec_block_start can be determined as follows.

[0623] Let C be the position of the first cell of the first complete FEC block before the CTI of the current PLP in the current subframe or a subsequent subframe, where the index of C starts from 0, and 0 corresponds to the first cell of the current physical layer channel before the CTI. In this case, C can be equal to the number of cells belonging to the physical layer channel that immediately precede the FEC block and have not yet been input to the convolutional temporal interleaver. In this case, L1D_plp_CTI_fec_block_start can be C + N_row × ((L1D_plp_CTI_start_row + C) modulo N_row).

[0624] When using LDM, the L1D_plp_CTI_fec_block_start signal can be sent separately for the core layer physical layer channel and the enhancement layer physical layer channel. This is because the start positions of the first complete FEC block of the core layer physical layer channel and the enhancement layer physical layer channel, which are already multiplexed together, are usually different.

[0625] Figure 31 This is a diagram illustrating the relationship between convolution time interleaving before and after convolution time interleaving.

[0626] Reference Figure 31 After convolutional temporal interleaving (CTI) is performed, the position (C, 3110) of the first cell of the first complete FEC block prior to CTI in the current subframe is changed to position (3120). In this case, L1D_plp_CTI_fec_block_start can indicate the position (3120) after CTI. In this case, L1D_plp_CTI_fec_block_start can be calculated after CTI, and L1D_plp_CTI_fec_block_start can be relative to the position prior to CTI. In this case, L1D_plp_CTI_fec_block_start can be C + N_row × ((L1D_plp_CTI_start_row + C) modulo N_row).

[0627] The position (3130) of the first unit of the second complete FEC block before convolutional temporal interleaving in the current subframe can be changed to a position before (before) the start position (3120) of the first complete FEC block by convolutional temporal interleaving. Even in this case, the start position (3120) of the first complete FEC block before temporal interleaving can be sent as L1D_plp_CTI_fec_block_start with a signal.

[0628] exist Figure 31In the example, L1D_plp_CTI_start_row can be signaled only for the core physical layer channel, and L1D_plp_CTI_start_row can be sent without signaling for the enhancement layer physical layer channel. In this case, the position of the interleaver selector for the enhancement layer physical layer channel can be calculated from the L1D_plp_CTI_start_row of the core physical layer channel corresponding to the current enhancement layer physical layer channel.

[0629] Figure 32 This is a diagram illustrating the case of a single physical layer channel with convolutional temporal interleaving (no temporal interleaving mode) applied at a depth of 0.

[0630] Reference Figure 32 An FEC block (#0, n0) is divided by the boundaries between subframes.

[0631] In this case, the fec_block_start,C_in(#1) of the first subframe can be {FEC_Block_size(#0)-{(L1D_plp_size(#0)-C_in(#0))%FEC_Block_size(#0))}}%FEC_Block_size(#0).

[0632] exist Figure 32 In the example, because time interleaving is not applied, C_in can be sent as a signal for L1D_plp_fec_block_start.

[0633] Figure 33 This is a diagram illustrating the operation on the receiver side in the case of a single physical layer channel.

[0634] Reference Figure 33 The receiver performs time deinterleaving and uses the received L1D_plp_CTI_fec_block_start to calculate the position (C_in) before time interleaving.

[0635] In this case, the position (C_in) before time interleaving can be L1D_plp_CTI_fec_block_start - (k × N_row). In this case, k can be the row corresponding to L1D_plp_CTI_fec_block_start, and can be (L1D_CTI_start_row + L1D_plp_CTI_fec_block_start) % N_row.

[0636] The parameters for convolutional temporal interleaving for a single physical layer channel can be calculated from the following signaling parameters. In this case, the parameters may correspond to the i-th subframe and the 0th physical layer channel.

[0637] -L1D_plp_CTI_depth(i-1)->N_row(i-1)

[0638] -L1D_plp_CTI_depth(i)->N_row(i)

[0639] -L1D_plp_size(i-1,0)

[0640] -L1D_plp_fec_type(i-1,0)&L1D_plp_mod(i-1,0)->FEC_Block_size(i-1,0)

[0641] -L1D_CTI_start_row(i,0)=(L1D_CTI_start_row(i-1,0)+L1D_plp_size(i-1,0))%N_row(i-1)

[0642] -L1D_CTI_fec_block_start(i)=C_in(i)+(n*N_row),

[0643] Among them, C_in(i)={FEC_Block_size(i-1,0)-{(L1D_plp_size(i-1,0)-C_in(i-1))%FEC_Block_size(i-1,0))}}%FEC_Block_size(i-1,0)

[0644] n=(L1D_CTI_start_row(i,0)+C_in(i))%N_row(i)

[0645] In this case, N_row(i-1) can be the same as N_row(i). If N_row(i-1) is different from N_row(i), the operation of the convolutional time interleaver can be reset.

[0646] The delay caused by CTI is calculated based on the i-th subframe.

[0647] Since the current C_in(i) is calculated based on the conditions of the previous subframe, other parameters are calculated based on the (i-1)th subframe.

[0648] The following section explains the various enhanced physical layer channel scenarios.

[0649] In this case, L1D_plp_CTI_fec_block_start can be sent individually via signal to each enhancement layer physical layer channel.

[0650] In this scenario, the L1D_CTI_start_row for the enhancement layer physical layer channel can be transmitted without signaling, and the L1D_CTI_start_row can be calculated and used on the receiver side. Alternatively, the L1D_CTI_start_row can be explicitly transmitted only for the core layer physical layer channel using signaling.

[0651] When at least two enhancement layer physical layer channels are multiplexed with one core layer physical layer channel, the L1D_CTI_start_row for the first enhancement layer physical layer channel can be the same as the L1D_CTI_start_row for the core layer physical layer channel. In this case, the L1D_CTI_start_row for the other enhancement layer physical layer channels can be calculated using some parameters.

[0652] Figure 34 and 35 This is a diagram showing the situation of multiple enhanced physical layer channels.

[0653] Reference Figure 34 An FEC block (#0, 1, n0) of the enhancement layer physical layer channel (enhancement PLP#1) is divided by the boundary between subframes.

[0654] In this case, the fec_block_start, C_in(#1,1) of the first physical layer channel in the first subframe can be {FEC_Block_size(#0,1)-{(L1D_plp_size(#0,1)-C_in(#0,1))%FEC_Block_size(#0,1))}}%FEC_Block_size(#0,1).

[0655] Typically, C_in(i,j) corresponding to the j-th enhancement layer physical layer channel in the i-th subframe can be {FEC_Block_size(i-1,j)-{(L1D_plp_size(i-1,j)-C_in(i-1,j))%FEC_Block_size(i-1,j))}}%FEC_Block_size(i-1,j).

[0656] Reference Figure 35 An FEC block (#0, 2, p0) of the enhancement layer physical layer channel (enhanced PLP#2) is divided by the boundary between subframes.

[0657] In this case, the fec_block_start, C_in(#1,2) of the second physical layer channel in the first subframe can be {FEC_Block_size(#0,2)-{(L1D_plp_size(#0,2)-C_in(#0,2))%FEC_Block_size(#0,2))}}%FEC_Block_size(#0,2).

[0658] The parameters for convolutional temporal interleaving for multiple enhancement layer physical layer channels can be calculated from the signaling parameters as follows. In this case, the parameters can correspond to the i-th subframe and the j-th enhancement layer physical layer channel.

[0659] -L1D_plp_CTI_depth(i-1)->N_row(i-1)

[0660] -L1D_plp_CTI_depth(i)->N_row(i)

[0661] -L1D_plp_size(i-1,j)

[0662] -L1D_plp_fec_type(i-1,j)&L1D_plp_mod(i-1,j)->FEC_Block_size(i-1,j)

[0663] -L1D_CTI_start_row(i,0)=(L1D_CTI_start_row(i-1,0)+L1D_plp_size(i-1,0))%N_row(i-1)

[0664] -L1D_CTI_fecframe_start(i)=C_in(i)+(n*N_row),

[0665] Among them, C_in(i)={FEC_Block_size(i-1,j)-{(L1D_plp_size(i-1,j)-C_in(i-1))%FEC_Block_size(i-1,j))}}%FEC_Block_size(i-1,j)

[0666] n=(L1D_CTI_start_row(i,j)+C_in(i))%N_row(i)

[0667] In this case, N_row(i-1) can be the same as N_row(i). If N_row(i-1) is not the same as N_row(i), the operation of the convolutional time interleaver can be reset.

[0668] In this scenario, the available signal transmission is limited to L1D_CTI_start_row for core layer physical layer channels or physical layer channels not multiplexed. In this case, the L1D_CTI_start_row for the first enhancement layer physical layer channel can be the same as the L1D_CTI_start_row for the core layer physical layer channel of the current CTI group (L1D_CTI_start_row(i, 0) in the example above). In this case, the L1D_CTI_start_row for the other enhancement layer physical layer channels can be calculated as follows.

[0669] When PLP#0 is the core layer physical layer channel and PLP#1 to #j are enhancement layer physical layer channels, the L1D_CTI_start_row of the enhancement layer physical layer channel can be calculated recursively as follows.

[0670] Core PLP#0:L1D_CTI_start_row(i,0)=(L1D_CTI_start_row(i-1,0)+L1D_plp_size(i-1,0))%N_row(i-1)

[0671] Enhanced PLP#1:L1D_CTI_start_row(i,1)=L1D_CTI_start_row(i,0)

[0672] Enhanced PLP#2:L1D_CTI_start_row(i,2)=(L1D_CTI_start_row(i,1)+L1D_plp_size(i,1))%N_row(i) ...

[0674] Enhanced PLP#j:L1D_CTI_start_row(i,j)=(L1D_CTI_start_row(i,j-1)+L1D_plp_size(i,j-1))%N_row(i)

[0675] When PLP#0 is a core layer physical layer channel and PLP#1 to #j are enhancement layer physical layer channels, the L1D_CTI_start_row of the enhancement layer physical layer channel can be calculated in the following closed form.

[0676] Core PLP#0:L1D_CTI_start_row(i,0)=(L1D_CTI_start_row(i-1,0)+L1D_plp_size(i-1,0))%N_row(i-1)

[0677] Enhanced PLP#1:L1D_CTI_start_row(i,1)=L1D_CTI_start_row(i,0)

[0678] Enhanced PLP#2:L1D_CTI_start_row(i,2)=(L1D_CTI_start_row(i,0)+L1D_plp_size(i,1))%N_row(i)

[0679] Enhanced PLP#3: L1D_CTI_start_row(i,3)=(L1D_CTI_start_row(i,0)+L1D_plp_size(i,1)+L1D_plp_size(i,2))%N_row(i) ...

[0681] Enhance

[0682] As described above, the apparatus and method for generating broadcast signal frames according to the present invention are not limited to the configurations and methods of the above embodiments, but some or all of the embodiments can be selectively combined to modify the embodiments in various ways.

Claims

1. A method for generating broadcast signal frames, comprising: Multiplexed signals are generated by combining core layer signals and enhancement layer signals; Reduce the power of the multiplexed signal to the power level corresponding to the core layer signal; A time-interleaved signal is generated by performing time interleaving applied to both the core layer signal corresponding to the core layer signal and the enhancement layer signal corresponding to the enhancement layer signal; and A broadcast signal frame is generated, wherein the broadcast signal frame includes a preamble for transmitting time interleaver information corresponding to the time interleaving via signaling. The time interleaving is performed using one of multiple operating modes. The plurality of operation modes include a first mode corresponding to no temporal interleaving, a second mode for performing convolutional temporal interleaving, and a third mode for performing mixed temporal interleaving. The preamble includes a first field indicating the start position of the first complete FEC block for the first mode corresponding to each physical layer channel, or a second field indicating the start position of the first complete FEC block for the second mode corresponding to each physical layer channel, but does not include any field indicating the start position of the first complete FEC block for the third mode. The second field has a longer length than the first field. The first field is 15 bits long, and the second field is 22 bits long. Wherein, when the time interleaving corresponds to the second mode, the start position of the first complete FEC block indicates the first cell of the first complete FEC block before convolutional time interleaving, and the position of the first cell of the first complete FEC block after convolutional time interleaving is sent by a signal.

2. The method as described in claim 1, wherein, The second field corresponds to the position after convolution time interleaving, which is calculated by adding the position (C) before convolution time interleaving and the delay caused by convolution time interleaving.

3. The method as described in claim 2, wherein, The latency caused by convolutional temporal interleaving is calculated by using the position (L1D_plp_CTI_start_row) of the interleaver selector corresponding to the convolutional temporal interleaving.

4. The method of claim 3, wherein, The latency caused by convolutional temporal interleaving is calculated using modulo operations on the following terms: The sum of the position of the interleaver selector corresponding to convolution-time interleaving and its position before convolution-time interleaving (L1D_plp_CTI_start_row + C), and The number of delay lines (N_row) corresponding to the convolution time interleaving.

5. The method of claim 4, wherein, The position of the interleaver selector is only sent with a signal for the core layer physical layer channel corresponding to the core layer, and the position of the interleaver selector is not sent with a signal for the enhancement layer physical layer channel corresponding to the enhancement layer.

6. The method of claim 5, wherein, The position of the interleaver selector for the enhancement layer physical layer channel is calculated by using the position of the interleaver selector that is signaled for the core layer physical layer channel corresponding to the enhancement layer physical layer channel.

7. The method of claim 1, wherein, The first field or the second field is sent using signals for the core layer physical layer channel and the enhancement layer physical layer channel, respectively.

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