Transmitting device, receiving device, transmission method, and receiving method

Abstract

To provide a transmitting device, a transmitting method, a receiving device, and a receiving method that can increase transmission capacity by effectively utilizing the available transmission capacity. [Solution] The transmitting device according to the embodiment includes a first modulation means that performs primary modulation with PSK or QAM and secondary modulation with OFDM on one or more hierarchical signals, and a second modulation means that performs primary modulation with PSK or QAM and secondary modulation with OFDM on a control signal. The first modulation means outputs one or more subcarriers from a plurality of subcarriers of the one or more hierarchical signals after primary modulation to a subcarrier synthesis means. The second modulation means frequency multiplexes one or more subcarriers of the control signal after primary modulation and one or more subcarriers input from a subframe division means to generate one OFDM symbol. The transmitting device transmits the output of the first modulation means and the output of the second modulation means by time division multiplexing within a frame.

Description

[Technical Field]

[0001] Embodiments of the present invention relate to a transmitting device, a receiving device, a transmitting method, and a receiving method. [Background technology]

[0002] As an example of a transmitting device used in a broadcasting system, a device is known that time-division multiplexes control signals and broadcast signals and transmits them as a single frame. Control signals are transmitted in a control signal section. Broadcast signals are transmitted in a broadcast signal section. The control signal section is set to be shorter than the broadcast signal section. Both the control signal section and the broadcast signal section transmit signals using a predetermined number of subcarriers. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-132909 [Non-patent literature]

[0004] [Non-Patent Document 1] Ministry of Internal Affairs and Communications, Information and Communications Council, Information and Communications Technology Subcommittee, Broadcasting Systems Committee (78th meeting), June 29, 2023, Document 78-4, Draft Report: Technical Conditions for Broadcasting Systems, https: / / www.soumu.go.jp / main_content / 000890353.pdf [Overview of the project] [Problems that the invention aims to solve]

[0005] The amount of information transmitted in a control signal may be less than the amount of information that can be transmitted within the control signal section. In this case, unused subcarriers are generated within the control signal section, and the transmitting device does not fully utilize its transmission capacity.

[0006] The object of the present invention is to provide a transmitting device, a receiving device, a transmitting method, and a receiving method that can increase transmission capacity by effectively utilizing the transmittable capacity. [Means for solving the problem]

[0007] The transmitting device according to the embodiment includes a subframe modulation means that performs primary modulation using Phase Shift Keying (PSK) or Quadrature Amplitude Modulation (QAM) and secondary modulation using Orthogonal Frequency Division Multiplexing (OFDM) on one or more hierarchical signals used in a broadcasting system, and a control signal modulation means that performs primary modulation using PSK or QAM and secondary modulation using OFDM on control signals used for at least one of synchronization and control in broadcast transmission, independently of the hierarchical signals. The subframe modulation means further includes a subframe splitting means. The control signal modulation means further includes a subcarrier combining means. The subframe splitting means outputs one or more subcarriers from a plurality of subcarriers of the one or more hierarchical signals after primary modulation to the subcarrier combining means. The subcarrier combining means frequency multiplexes one or more subcarriers of the control signal after primary modulation and one or more subcarriers input from the subframe splitting means to generate one OFDM symbol. The transmitting device transmits the output of the subframe modulation means and the output of the control signal modulation means by time-division multiplexing within a frame. [Brief explanation of the drawing]

[0008] [Figure 1] A diagram illustrating an example of the frame configuration of the advanced terrestrial broadcasting system according to the first embodiment. [Figure 2] A block diagram illustrating an example of a frame component included in a transmitting device according to the first embodiment. [Figure 3] A block diagram illustrating an example of a subframe section generation unit and an Lch separation unit according to the first embodiment. [Figure 4]A diagram illustrating an example of a time-division multiplexed frame configuration (without partial reception bandwidth) according to the first embodiment. [Figure 5] This diagram illustrates the signal (number of subcarriers) after primary modulation of the information bits in Transmission and Multiplexing Configuration Control (TMCC). [Figure 6] A diagram illustrating the number of primary modulated signals that can be transmitted in one OFDM symbol within a TMCC section. [Figure 7] A diagram illustrating an example of a frame configuration (without partial reception bandwidth). [Figure 8] A diagram illustrating another example of frame configuration (without partial receiving bandwidth). [Figure 9] This diagram illustrates the number of subcarriers output from the subframe division section of the subframe interval generation section to the TMCC interval generation section. [Figure 10] A block diagram illustrating an example of a TMCC section generation unit according to the first embodiment. [Figure 11] A diagram illustrating an example of a time-division multiplexed frame configuration with a partial receiving bandwidth according to the first embodiment. [Figure 12] A block diagram illustrating an example of a receiving device according to the second embodiment. [Figure 13] A block diagram illustrating an example of a TMCC demodulation unit according to the second embodiment. [Figure 14] A block diagram illustrating an example of a subframe demodulation unit according to the second embodiment. [Figure 15] A diagram illustrating an example of the transmission order of the B layer of subframes in the case of partial reception bandwidth according to the first embodiment. [Figure 16] A diagram illustrating another example of the transmission sequence image of the B layer of subframes in the case of partial receiving bandwidth according to the first embodiment. [Figure 17] A diagram illustrating another example of the transmission sequence image of the B layer of subframes in the case of partial receiving bandwidth according to the first embodiment. [Figure 18]A diagram illustrating an example of the transmission order of the B layer of subframes in the case of partial receiving bandwidth according to the third embodiment. [Figure 19] A diagram illustrating another example of the transmission sequence image of the B layer of subframes in the case of partial receiving bandwidth according to the third embodiment. [Figure 20] A diagram illustrating another example of the transmission sequence image of the B layer of subframes in the case of partial receiving bandwidth according to the third embodiment. [Figure 21] A diagram illustrating an example of a frame configuration according to a modification of the third embodiment, in which the beginning and middle portions of each frame are transmitted in the TMCC section of the next frame. [Figure 22] A diagram illustrating another example of a frame configuration relating to a modification of the third embodiment, in which the leading and middle portions of each frame are transmitted in the TMCC section of the next frame. [Figure 23] A block diagram illustrating an example of a modulation section in the subframe section generation section of a transmitting device according to the third embodiment. [Figure 24] A block diagram illustrating an example of the TMCC demodulation unit of a receiving device according to the fourth embodiment. [Figure 25] A diagram illustrating an example of a frame configuration in the case of a partial receiving bandwidth according to the fifth embodiment. [Figure 26] A diagram illustrating an example of a segment configuration according to the seventh embodiment. [Figure 27] A diagram illustrating an example of a frame configuration in the case of no partial receiving bandwidth according to the seventh embodiment. [Modes for carrying out the invention]

[0009] The embodiments will be described below with reference to the drawings. The following description illustrates devices and methods for realizing the technical idea of ​​the embodiments, and the technical idea of ​​the embodiments is not limited to the structure, shape, arrangement, material, etc. of the components described below. Modifications that a person skilled in the art can easily conceive of are naturally included in the scope of disclosure. In some cases, the same reference numeral is used for corresponding elements in multiple drawings, and redundant descriptions are omitted. Some elements may be given multiple names, but these examples of names are merely illustrative and do not preclude the use of other names for these elements. Similarly, elements that do not have multiple names may also be given other names. "Connection" may include not only direct connections but also connections via other elements. Unless the number of elements is explicitly stated as multiple, the element may be singular or plural.

[0010] [First Embodiment] Figure 1 is a diagram illustrating an example of the frame configuration of the advanced terrestrial broadcasting system according to the first embodiment. In Figure 1, the horizontal axis represents time, and the vertical axis represents frequency. A frame consists of a frame synchronization signal section, a TMCC section, one or more subframe sections, and an extension section. Figure 1 shows a case where two subframes are included: subframe 1 and subframe 2. A subframe consists of one or more layers with a segment structure. One subframe consists of multiple symbols with the same symbol length. The transmission control information transmitted in the TMCC section has a variable length of information. An extension section may be provided at the end of the frame.

[0011] This method also supports partial reception, which selectively receives only a portion of the frequency band of the transmitted signal. The pilot signal Lch, which can also be used as a transmission path characterized by high tolerance and low latency, can be transmitted across the entire frame, excluding the frame synchronization signal section and the TMCC section. After one frame is transmitted, the next frame is transmitted chronologically consecutively. Note that extended sections may not be included within a frame. Also, the scale in Figure 1 is not necessarily accurate.

[0012] Figure 2 is a block diagram illustrating an example of a frame configuration unit 10 provided in a transmitting device according to the first embodiment. The frame configuration unit 10 consists of an input interface (hereinafter also referred to as input I / F) 12, a frame synchronization signal section generation unit 14, a TMCC section generation unit 16, a subframe 1 section generation unit 18, a subframe 2 section generation unit 20, an Lch separation unit 22, and a time-division multiplexed frame configuration unit 24. Control signals and transmission signals necessary for configuring a time-division multiplexed frame are input to the input I / F 12. The input I / F 12 outputs the control signal necessary for generating a frame synchronization signal to the frame synchronization signal section generation unit 14, the control signal or transmission signal necessary for generating a TMCC to the TMCC section generation unit 16, the control signal or transmission signal necessary for generating a subframe 1 to the subframe 1 section generation unit 18, the control signal or transmission signal necessary for generating a subframe 2 to the subframe 2 section generation unit 20, and the control signal or transmission signal necessary for the Lch separation unit to the Lch separation unit 22.

[0013] The frame synchronization signal section generation unit 14 generates the signal for the frame synchronization signal section. The TMCC section generation unit 16 generates the signal for the TMCC section. The subframe 1 section generation unit 18 generates the signal for the subframe section of subframe 1. Similarly, the subframe 2 section generation unit 20 generates the signal for the subframe section of subframe 2. The Lch separation unit 22 separates the Lch signal from the input signal and outputs it to the subframe 1 section generation unit 18 and the subframe 2 section generation unit 20.

[0014] The time-division multiplexed frame constructor 24 time-division multiplexes the output of the frame synchronization signal section generation unit 14, the output of the TMCC section generation unit 16, the output of the subframe 1 section generation unit 18, and the output of the subframe 2 section generation unit 20 and outputs it. The subframe 1 section generation unit 18 outputs a portion of the modulated signal to the TMCC section generation unit 16. The TMCC section generation unit 16 multiplexes the signal of the TMCC section with the signal of the subframe section of subframe 1. Alternatively, the subframe 2 section generation unit 20 may output a portion of the modulated signal to the TMCC section generation unit 16, and the TMCC section generation unit 16 may multiplex the signal of the TMCC section with the signal of the subframe section of subframe 1 and the signal of the subframe section of subframe 2. Figure 2 shows an example where there are two subframe section generation units, but there may be only one subframe section generation unit, or there may be three or more.

[0015] The output of the time-division multiplexed frame component 24 is output to the transmission circuit 26 and converted into a high-frequency signal (RF signal). The RF signal output by the transmission circuit 26 is transmitted via the transmission antenna 28. The transmitting device includes the frame component 10, the transmission circuit 26, and the transmission antenna 28.

[0016] Figure 3 is a block diagram illustrating an example of the subframe interval generation units 18, 20 and Lch separation unit 22 according to the first embodiment. The subframe interval generation units 18, 20 consist of an input I / F 32, a first-order modulation unit 34 for each layer, a subframe division unit 36, a division subcarrier number calculation unit 38, a level adjustment unit 40 for each layer, a layer combining unit 42, a band division unit 44, a time interleaving unit (hereinafter also referred to as the time IL unit) 46, a frequency interleaving unit (hereinafter also referred to as the frequency IL unit) 48, a band combining unit 50, a pilot generation unit 52, a differential reference addition unit 54, a Differential Binary Phase Shift Keying (DBPSK) modulation unit 56, an OFDM frame configuration unit 58, an Inverse Fast Fourier Transform (IFFT) unit 60, and a Guard interval (GI) addition unit 62.

[0017] The input interface 32 distributes the control signals or transmission signals assigned to the subframes to each layer. The input interface 32 distributes the control signals necessary for calculating the number of divided subcarriers to the divided subcarrier number calculation unit 38. The input interface 32 distributes the control information (pilot placement information) necessary for generating the pilot signal to the pilot generation unit 52. The input interface 32 outputs the control signals or transmission signals necessary for the Lch separation unit 22 to the differential reference addition unit 54. The Lch separation unit 22 includes the differential reference addition unit 54 and the DBPSK modulation unit 56. A block of information transmitted on the pilot signal Lch is called an Lch frame. Up to eight layers are defined, from layer A to layer H. The primary modulation units 34a, 34b, ... 34h of each layer A, B, ... H are connected to the input interface 32. The primary modulation units 34a, 34b, ..., 34h perform primary modulation on the hierarchical frames using Phase Shift Keying (PSK) or Quadrature Amplitude Modulation (QAM). The primary modulation units 34a, 34b, ..., 34h may also perform energy spreading, error correction coding, and bit interleaving on the input data. For example, error correction coding may involve encoding with BCH coding followed by Low Density Parity Check (LDPC) coding. Some parts of the following explanation assume that BCH coding is the outer code and LDPC coding is the inner code.

[0018] The subframe division unit 36 ​​receives the number of subcarriers for each layer of subframe 1 from the sub-subcarrier count calculation unit 38 and receives the signal after primary modulation from the primary modulation units 34a, 34b, ... 34h. Each signal after primary modulation corresponds to a subcarrier included in the OFDM symbol. The subframe division unit 36 ​​outputs the number of subcarriers for each layer from the input subcarriers of each layer to the TMCC section generation unit 16, and outputs the remaining subcarriers to the level adjustment units 40a, 40b, ... 40h of the same layer as the input layer. The sub-subcarrier count calculation unit 38 calculates the number of subcarriers for each layer and outputs it to the subframe division unit 36.

[0019] For example, let the number of sub - carriers in layer A input from the divided sub - carrier number calculation unit 38 be C A , let the number of sub - carriers in layer B input from the divided sub - carrier number calculation unit 38 be C B , let the number of sub - carriers for one sub - frame input from the first - order modulation unit 34a in layer A be C A_all , let the number of sub - carriers for one sub - frame input from the first - order modulation unit 34b in layer B be C B_all , and assume that there is no input after layer C. Among the layers, the layer earlier in alphabetical order is the upper layer. In this example, layer A is the upper layer. The sub - frame division unit 36 outputs only C A sub - carriers of layer A to the TMCC interval generation unit 16, and outputs the remaining (C A_all -C A ) sub - carriers to the level adjustment unit 40a of layer A. Similarly, the sub - frame division unit 36 outputs only C B sub - carriers of layer B to the TMCC interval generation unit 16, and outputs the remaining (C B_all -C B ) sub - carriers to the level adjustment unit 40b of layer B. When the number of sub - carriers of a certain layer input from the divided sub - carrier number calculation unit 38 is 0, the number of sub - carriers of a certain layer output by the sub - frame division unit 36 to the TMCC interval generation unit 16 is 0, and the sub - frame division unit 36 outputs all the sub - carriers input from a certain layer to the level adjustment unit 40 of a certain layer.

[0020] The level adjustment units 40a, 40b,... 40h of each layer perform level adjustment on the input signals. The layer synthesis unit 42 synthesizes the signals of each layer. The band division unit 44 divides the signal after layer synthesis into bands. The time IL unit 46 interleaves the signal after band division in time. The frequency IL unit 48 interleaves the signal after time interleaving in frequency. The band synthesis unit 50 synthesizes the signal after frequency interleaving to form a data segment.

[0021] The pilot generation unit 52 generates a pilot signal for transmission path estimation according to predetermined parameters and outputs it to the OFDM frame configuration unit 58. The pilot generation unit 52 also outputs pilot placement information to the OFDM frame configuration unit 58.

[0022] The differential reference addition unit 54 adds a differential reference bit to the beginning of each subframe of the Lch frame. The DBPSK modulation unit 56 modulates the output of the differential reference addition unit 54 using DBPSK to generate an Lch signal and outputs the Lch signal to the OFDM frame constructor 58. The Lch signal is a pilot signal for broadband frequency synchronization and noise estimation, and can also be used for data transmission.

[0023] The OFDM frame constructor 58 adds a pilot signal and an Lch signal to the data segment from the bandwidth combining unit 50 to construct an OFDM frame. The position where the pilot signal is added is determined based on pilot placement information. The IFFT unit 60 performs an IFFT on the signal after the OFDM frame has been constructed. The OFDM frame constructor 58 and the IFFT unit 60 constitute the secondary modulation unit 64.

[0024] The GI addition unit 62 adds GI to the signal after IFFT and outputs the GI-added signal.

[0025] The sub-carrier count calculation unit 38 calculates the number of subcarriers to be output from the subframe division unit 36 ​​of the subframe interval generation units 18 and 20 to the TMCC interval generation unit 16. The calculation method is to subtract the number of subcarriers of the TMCC information bits after primary modulation from the number of signals (subcarrier count) that can be transmitted by the TMCC after primary modulation. An example of the specific calculation method is shown below.

[0026] Figure 4 is a diagram illustrating an example of a time-division multiplexed frame configuration (without partial receiving bandwidth) according to the first embodiment. Figure 4 illustrates an example in which one frame contains two subframes, subframe 1 and subframe 2, with subframe 1 consisting of A-layer and B-layer, and subframe 2 consisting of A-layer. The TMCC information bits are contained in one Forward Error Correction (FEC) block and are transmitted twice using repeat coding. The signal after repeat coding is transmitted with two OFDM symbols, and the remaining portion of the second OFDM symbol is allocated to the A-layer and B-layer signals of subframe 1, thereby forming a frame.

[0027] In this embodiment, the subcarriers of each layer of subframe 1 were output to the TMCC section generation unit 16. However, the subcarriers of each layer of subframe 2 and subsequent layers may also be output to the TMCC section generation unit 16, or the subcarriers of each layer of subframes specified by the frame synchronization signal or TMCC may be output to the TMCC section generation unit 16.

[0028] This explains the number of primary modulated signals (number of subcarriers) that can be transmitted in a TMCC section.

[0029] Figure 5 shows the signal (number of subcarriers) N ​​after primary modulation of the TMCC information bits. TMCC_MOD This is a diagram to explain the (× region).

[0030] Number of bits in TMCC information: K T Number of parity bits in a BCH code: P o (=168) Number of information bits in an LDPC code: K i (=252) Number of parity bits in an LDPC code: P L (=972,2196) Number of iterations: R Modulation multi-level number: M (=1(BPSK), 2(QPSK)) The signal (number of subcarriers) after primary modulation of the TMCC information bits transmitted in one frame after iterative coding: N TMCC_MODThis is expressed by Equation 1.

[0031] N TMCC_MOD =ceil((K T +P o ) / K i )×(K i +P L )×R / M Equation 1 K T +P o This represents the code length of the BCH.

[0032] K i +P L This represents the code length of the LDPC.

[0033] ceil((K T +P o ) / K i ) represents the number of blocks in the LDPC code.

[0034] ceil(X) represents the smallest integer greater than or equal to X.

[0035] Figure 6 shows the number of primary modulated signals C that can be transmitted in one OFDM symbol in the TMCC section. TMCC_CAP This is a diagram to explain the (× region).

[0036] Number of subcarriers per segment in TMCC: C seg (=216(8k),432(16k),864(32k)) Number of pilots per segment in TMCC: C P (=4,36,72,144,288) Number of Lch per segment of TMCC: C L (=4,8,16) Number of segments: S (=35) The number of primary modulated signals (subcarriers) that can be transmitted in one OFDM symbol within a TMCC section is C. TMCC_CAP This is expressed by Equation 2.

[0037] C TMCC_CAP =(C seg -C p -CL )×S Equation 2 The number of OFDM symbols Os in the TMCC section transmitted in one frame is expressed by Equation 3.

[0038] Os=ceil(N TMCC_MOD / C TMCC_CAP ) Equation 3 The total number of subcarriers C across all layers is output from the subframe division unit 36 ​​of the subframe interval generation unit to the TMCC interval generation unit 16. all_lay It is calculated as shown in Equation 4.

[0039] C all_lay =Os×C TMCC_CAP -N TMCC_MOD =ceil(N TMCC_MOD / C TMCC_CAP )×C TMCC_CAP -N TMCC_MOD =ceil((ceil((K T +P o ) / K i )×(K i +P L )×R / M) / ((C seg -C p -C L )×S))×((C seg -C p -C L )×S)-(ceil((K T +P o ) / K i )×(K i +P L )×R / M) Equation 4 ceil(N TMCC_MOD / C TMCC_CAP )×C TMCC_CAP This represents the number of subcarriers in the TMCC section transmitted in one frame.

[0040] Number of segments in the X hierarchy of subframe 1: S 1X (X represents the hierarchy from A to H) Number of subcarriers C in the TMCC section that can be transmitted with the number of segments in layer A of subframe 1 TMCC_1A This is calculated as shown in Equation 5.

[0041] C TMCC_1A =(C seg -C p -C L )×S 1A Equation 5 FIG. 7 is a diagram for explaining an example of the frame configuration (without partial reception band) in the case of C all_lay ≦C TMCC_1A . C all_lay ≦C TMCC_1A In the case of, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the A layer of sub-frame 1 to the TMCC interval generation unit 16 is C all_lay , and the number of sub-carriers output from other layers is 0.

[0042] FIG. 8 is a diagram for explaining an example of the frame configuration (without partial reception band) in the case of C all_lay >C TMCC_1A . C all_lay >C TMCC_1A In the case of, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the A layer of sub-frame 1 to the TMCC interval generation unit 16 is C TMCC_1A .

[0043] C all_lay -C TMCC_1A ≦C TMCC_1B In the case of, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the B layer of sub-frame 1 to the TMCC interval generation unit 16 is (C all_lay -C TMCC_1A ), and the number of sub-carriers output from the C layer to the H layer is 0.

[0044] C all_lay -C TMCC_1A >C TMCC_1B In the case of, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the B layer of sub-frame 1 to the TMCC interval generation unit 16 is C TMCC_1B .

[0045] C all_lay -(C TMCC_1A +CTMCC_1B ) ≤ C TMCC_1C In this case, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the C layer of sub-frame 1 to the TMCC interval generation unit 16 is (C all_lay -(C TMCC_1A + C TMCC_1B )), and the number of sub-carriers output from the D layer to the H layer is 0.

[0046] C all_lay -(C TMCC_1A + C TMCC_1B ) > C TMCC_1C In this case, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the C layer of sub-frame 1 to the TMCC interval generation unit 16 is C TMCC_1C .

[0047] Hereinafter, the D layer, E layer, F layer, G layer, and H layer can be calculated in the same way.

[0048] Note that the number of sub-carriers output from each layer after sub-frame 2 to the TMCC interval generation unit 16 is 0.

[0049] FIG. 9 is a diagram for explaining the number of sub-carriers output from the sub-frame division unit 36 of the sub-frame interval generation units 18 and 20 calculated by the divided sub-carrier number calculation unit 38 to the TMCC interval generation unit 16. The divided sub-carrier number calculation unit 38 subtracts the number of sub-carriers N in the range indicated by × in FIG. 5 from the number of sub-carriers after first modulation that can be transmitted in the TMCC interval. TMCC_MOD to subtract.

[0050] The subcarrier number calculation unit 38 receives the information necessary for the above calculation via input I / F 12 and 32 and outputs the calculated subcarrier number for each layer. Of the information necessary for the above calculation, information that is defined as a single value in the broadcasting system may be stored and used in the subcarrier number calculation unit 38. For example, the number of parity bits of the BCH code, the number of information bits of the LDPC code, and the number of segments may be stored in the storage unit. Alternatively, related information may be input to the subcarrier number calculation unit 38 instead of the above specific values, and the subcarrier number calculation unit 38 may convert the information and use it to calculate the number of subcarriers. For example, the subcarrier number calculation unit 38 may input the Fast Fourier Transform (FFT) size of the TMCC supplied via input I / F 12 and 32, refer to a table, and determine the number of Lch.

[0051] The following are the configurable parameters for the FFT size of TMCC. The FFT size can be one of 8k, 16k, or 32k, and the possible values ​​for each parameter change accordingly.

[0052] The number of parity bits, the number of iterations, and the modulation level of the LDPC code can be set independently of the FFT size.

[0053] [Table 1]

[0054] [Table 2]

[0055] [Table 3]

[0056] Figure 10 is a block diagram illustrating an example of a TMCC interval generation unit 16 according to the first embodiment. The TMCC interval generation unit 16 consists of a padding unit 72, an energy diffusion unit 74, a BCH coding unit 76, an LDPC coding unit 78, a repetition coding unit 80, a carrier modulation unit 82, a subcarrier synthesis unit 84, a TMCC data segment structuring unit 86, a phase rotation unit 88, a frequency IL unit 90, a TMCC frame structuring unit 92, an IFFT unit 94, and a GI addition unit 96.

[0057] The padding unit 72 adds padding bits to the bits of the TMCC information. This is to adjust the length to an integer multiple of the FEC block length when error correction coding is performed by the BCH coding unit 76. The energy diffusion unit 74 calculates the exclusive OR of the sequence obtained by adding padding bits to the input TMCC information and a predetermined diffusion sequence, and outputs the calculated sequence. The BCH coding unit 76 divides the input sequence (bit sequence) into bit sequences of a predetermined length and performs BCH coding on each bit sequence. The LDPC coding unit 78 performs LDPC coding on the encoded bit sequence. The repetition coding unit 80 repetitions the LDPC coded bit sequence a specified number of times. The specified number of times is specified by the frame synchronization signal.

[0058] The carrier modulation unit 82 modulates the input bit sequence using Binary Phase-Shift Keying (BPSK) or Quadrature Phase-Shift Keying (QPSK). The carrier modulation unit 82 is also referred to as the first-order modulation unit. The subcarrier synthesis unit 84 synthesizes the signal input from the carrier modulation unit 82 and the signal input from the subframe 1 section generation unit 18. The TMCC data segment constructor unit 86 constructs the TMCC data segment. The phase rotation unit 88 applies phase rotation in the carrier direction. The frequency interleaving unit 90 performs frequency interleaving processing.

[0059] The TMCC frame constructor 92 adds a pilot signal and an Lch signal to the signal after frequency interleaving to construct a TMCC frame. The IFFT unit 94 performs an IFFT on the signal after TMCC frame construction. The TMCC frame constructor 92 and the IFFT unit 94 constitute a secondary modulation unit 98. The secondary modulation unit 98 constructs an OFDM frame for the TMCC section. The GI addition unit 96 adds GI to the output of the secondary modulation unit 98 and outputs the signal with GI added.

[0060] The primary modulation unit (carrier modulation unit) 82 modulates independently of the primary modulation units 34a-34h of the subframe section generation units 18 and 20. The primary modulation unit (carrier modulation unit) 82 is independent of the primary modulation units 34a-34h. Although it modulates independently, the modulation rate of the primary modulation unit (carrier modulation unit) 82 and the modulation rate of the primary modulation units 34a-34h of the subframe section generation units 18 and 20 may coincide.

[0061] Figure 11 is a diagram illustrating an example of a time-division multiplexed frame configuration in the case of partial reception band according to the first embodiment. The case of partial reception band refers to a situation where only a portion of the frequency band of the transmission signal can be selectively received. The number of segments in the transmission signal of the advanced terrestrial broadcasting system is 35. In the case of partial reception band, 9 segments close to the center frequency are called the partial reception band, and the other 26 segments are called the non-partial reception band. The same TMCC symbol is assigned to both the partial and non-partial reception bands. In the case of partial reception band, A-level signals are included in the partial reception band, and A-level signals are never included in the non-partial reception band.

[0062] In the partial reception band, no segments are time-interleaved. In the non-partial reception band, the TMCC segment is not time-interleaved, but subframe 1 is time-interleaved.

[0063] If there is no partial reception bandwidth, the entire bandwidth (the bandwidth of 35 segments) is not a partial reception bandwidth. The presence or absence of a partial reception bandwidth is indicated by the frame synchronization signal. Figures 4 to 9 show examples of frame configurations when there is no partial reception bandwidth.

[0064] Figure 11 shows an example where one subframe in a single frame is subframe 1, which consists of A and B layers, and there is no extended section. Furthermore, the TMCC information bits are contained in one FEC block and transmitted twice using repeat coding. In the partial reception band, the repeat coded signal is transmitted with five OFDM symbols, and the remaining portion of the fifth OFDM symbol is allocated to the A and B layer signals of subframe 1. In the non-partial reception band, the repeat coded signal is transmitted with two OFDM symbols, and the remaining portion of the second OFDM symbol and the third through fifth OFDM symbols are allocated to the B layer signal of subframe 1. The frame is constructed in this way.

[0065] When a partial reception band is available, the number of subcarriers in each layer of the partial reception band calculated by the subcarrier number calculation unit 38 is as follows:

[0066] Number of bits in TMCC information: K T Number of parity bits in a BCH code: P o (=168) Number of information bits in an LDPC code: K i (=252) Number of parity bits in an LDPC code: P L (=972,2196) Number of iterations: R Modulation multi-level number: M (=1(BPSK), 2(QPSK)) The signal (number of subcarriers) after primary modulation of the TMCC information bits transmitted in one frame is N. TMCC_MOD This is expressed by equation 6.

[0067] N TMCC_MOD =ceil((KT +P o ) / K i )×(K i +P L )×R / M Equation 6 Equation 6 is the same as Equation 1.

[0068] Number of subcarriers per segment in TMCC: C seg (=216(8k),432(16k),864(32k)) Number of pilots per segment in TMCC: C P (=4,36,72,144,288) Number of Lch per segment of TMCC: C L (=4,8,16) Number of segments: S part (=9) The number of primary modulated signals C that can be transmitted in the partial receiving bandwidth of one OFDM symbol in the TMCC section. TMCC_CAP_part This is represented by Equation 7.

[0069] C TMCC_CAP_part =(C seg -C p -C L )×S part formula 7 The number of OFDM symbols Os1 in the TMCC section transmitted in one frame is expressed by Equation 8.

[0070] Os1=ceil(N TMCC_MOD / C TMCC_CAP_part ) Equation 8 The total number of subcarriers across all layers of the partial receiving band output from the subframe division unit 36 ​​of the subframe section generation unit to the TMCC section generation unit 16 is calculated as shown in Equation 9.

[0071] C all_lay_part =ceil(N TMCC_MOD / C TMCC_CAP_part )×C TMCC_CAP_part -N TMCC_MOD formula 9 Number of segments in the X hierarchy of subframe 1: S 1X (X represents the hierarchy from A to H) The number of subcarriers in the TMCC section that can be transmitted using the number of A-layer segments in subframe 1 is calculated as shown in Equation 10.

[0072] C TMCC_1A =(C seg -C p -C L )×S 1A Formula 10 Equation 10 is the same as Equation 5.

[0073] C all_lay_part ≤C TMCC_1A In this case, the subframe division unit 36 ​​of the subframe interval generation unit outputs the number of subcarriers from the A layer of subframe 1 to the TMCC interval generation unit 16 as C all_lay_part Therefore, the number of subcarriers in the partial receiving band output from other layers is 0.

[0074] C all_lay_part >C TMCC_1A In this case, the subframe division unit 36 ​​of the subframe interval generation unit outputs the number of subcarriers from the A layer of subframe 1 to the TMCC interval generation unit 16 as C TMCC_1A That is the case.

[0075] C all_lay_part -C TMCC_1A ≤C TMCC_1B In this case, the subframe division unit 36 ​​of the subframe interval generation unit outputs the number of subcarriers from the B layer of subframe 1 to the TMCC interval generation unit 16 (C all_lay_part -C TMCC_1A ) and the number of subcarriers output from the C-H layers is 0.

[0076] C all_lay_part -C TMCC_1A >C TMCC_1B In this case, the subframe division unit 36 ​​of the subframe interval generation unit outputs the number of subcarriers from the B layer of subframe 1 to the TMCC interval generation unit 16 to C TMCC_1B That is the case.

[0077] The same calculations can be performed for the C, D, E, F, G, and H levels.

[0078] Number of segments: S nonpart (=26) The number of primary modulated signals C that can be transmitted in the non-partial receive bandwidth of one OFDM symbol in the TMCC section. TMCC_CAP_nonpart This is represented by equation 11.

[0079] C TMCC_CAP_nonpart =(C seg -C p -C L )×S nonpart Formula 11 The number of OFDM symbols Os2 in the TMCC section transmitted in one frame is expressed by Equation 12.

[0080] Os2=ceil(N TMCC_MOD / C TMCC_CAP_part ) Equation 12 The total number of subcarriers across all layers of the non-partially received band output from the subframe division unit 36 ​​of the subframe section generation unit to the TMCC section generation unit 16 is calculated as shown in Equation 13.

[0081] C all_lay_nonpart =Os2×C TMCC_CAP_nonpart -N TMCC_MOD =ceil(N TMCC_MOD / C TMCC_CAP_part )×C TMCC_CAP_nonpart -N TMCC_MOD Formula 13 Number of segments in the Y hierarchy of subframe 1: S 1Y (Y represents the hierarchy from B to H) The number of subcarriers in the non-partially received band within the TMCC section that can be transmitted using the number of segments in layer B of subframe 1 is calculated as shown in Equation 14.

[0082] C TMCC_1B_nonpart =(C seg -C p -C L )×S 1B formula 14 C all_lay_nonpart ≤C TMCC_1B_nonpartIn this case, the subframe division unit 36 ​​of the subframe section generation unit outputs the number of subcarriers of the non-partially received band from the B layer of subframe 1 to the TMCC section generation unit 16, C all_lay_nonpart Therefore, the number of subcarriers in the non-partially received band output from other layers is 0.

[0083] C all_lay_nonpart >C TMCC_1B_nonpart In this case, the subframe division unit 36 ​​of the subframe section generation unit outputs the number of subcarriers of the non-partially received band from the B layer of subframe 1 to the TMCC section generation unit 16, C TMCC_1B_nonpart That is the case.

[0084] C all_lay_nonpart -C TMCC_1B_nonpart ≤C TMCC_1C_nonpart In this case, the subframe division unit 36 ​​of the subframe section generation unit outputs the number of subcarriers of the non-partially received band from the C layer of subframe 1 to the TMCC section generation unit 16 (C all_lay_nonpart -C TMCC_1B_nonpart ) and the number of subcarriers output from the D-H layers is 0.

[0085] C all_lay_nonpart -C TMCC_1B_nonpart >C TMCC_1C_nonpart In this case, the subframe division unit 36 ​​of the subframe section generation unit outputs the number of subcarriers of the non-partially received band from the C layer of subframe 1 to the TMCC section generation unit 16, which is C TMCC_1C_nonpart That is the case.

[0086] The same calculations can be performed for the following D, E, F, G, and H levels.

[0087] In the first embodiment, the transmitting device does not necessarily have a number of bits of control signals transmitted in a TMCC section of one frame that is an integer multiple of the number of bits that can be transmitted in one OFDM symbol. If a fractional number occurs, the device assigns subcarriers of the hierarchical signal transmitted in a subframe to the remaining subcarriers of the OFDM symbol in the TMCC section to configure the OFDM symbol. As a result, the transmission capacity of the hierarchical signal is improved.

[0088] The transmitting device according to the first embodiment includes a subcarrier division number calculation unit and calculates the above fractional amount. As a result, the hierarchical signal can be transmitted without excess or deficiency using that fractional amount, and the transmission capacity of the hierarchical signal is improved.

[0089] [Second Embodiment] Figure 12 is a block diagram illustrating an example of a receiving device according to the second embodiment. The receiving device consists of an antenna 102, an RF unit 104, a synchronization unit 106, a TMCC demodulation unit 108, a subframe 1 demodulation unit 110, and a subframe 2 demodulation unit 112.

[0090] Antenna 102 outputs the received RF band signal. RF unit 104 performs filtering to limit the bandwidth of the RF band signal, Automatic Gain Control (AGC) processing to convert the signal level, down-conversion processing to convert the RF band signal to an IF band signal, and Analog-to-Digital Converter (ADC) processing to convert the analog signal to a digital signal.

[0091] The synchronization unit 106 performs quadrature demodulation, downsampling, automatic frequency control (AFC) processing for frequency conversion, timing synchronization, and frame synchronization signal demodulation processing on the digital signal input from the RF unit 104.

[0092] The TMCC demodulator 108 receives control information obtained by demodulating the synchronized signal and frame synchronization signal from the synchronization unit 106. Based on the control information, the TMCC demodulator 108 demodulates the synchronized signal and obtains control information not included in the frame synchronization signal. The TMCC demodulator 108 outputs the synchronized signal and a portion of their control information to each subframe demodulator.

[0093] The subframe 1 demodulator 110 demodulates subframe 1. The subframe 2 demodulator 112 demodulates subframe 2.

[0094] Although an example with subframe 1 demodulation unit 110 and subframe 2 demodulation unit 112 has been shown, there may be three or more subframe demodulation units, or just one. One subframe demodulation unit may demodulate multiple subframes.

[0095] Figure 13 is a block diagram illustrating an example of the TMCC demodulation unit 108 according to the second embodiment. The TMCC demodulation unit 108 consists of an FFT unit 114, an equalization processing unit 116, a frequency deinterleaving unit (also referred to as a frequency de-IL unit) 118, a phase inversion unit 120, a subcarrier splitting unit 122, a subframe subcarrier number calculation unit 124, a carrier synthesis unit 126, an error correction unit 128, an energy inverse diffusion unit 130, and a parameter extraction unit 132.

[0096] The FFT unit 114 takes the synchronously processed signal input to the TMCC demodulation unit 108, performs symbol timing synchronization to remove GI, and then performs FFT processing to convert the time-domain signal into a frequency-domain signal and output subcarriers. The equalization processing unit 116 performs frequency equalization processing on the input subcarriers. The frequency de-IL unit 118 performs frequency deinterleaving processing. The phase reversal rotation unit 120 reverses the phase.

[0097] The subcarrier splitting unit 122 splits a portion of the input phase-reverse-rotated subcarriers based on the value input from the subframe subcarrier number calculation unit 124, outputs the split portion of subcarriers to the subframe 1 demodulation unit 110 and the subframe 2 demodulation unit 112, and outputs the remaining subcarriers to the carrier synthesis unit 126.

[0098] The carrier synthesis unit 126 synthesizes the repeatedly coded subcarriers and performs repeated decoding. The error correction unit 128 performs LDPC decoding and BCH decoding on the repeatedly decoded signal. The energy dediffusion unit 130 calculates the exclusive OR of the decoded signal with a predetermined diffusion sequence and outputs the calculated sequence. The parameter extraction unit 132 extracts parameters from the input sequence and outputs some of them to the subframe 1 demodulation unit 110 and the subframe 2 demodulation unit 112.

[0099] The subframe subcarrier number calculation unit 124 calculates the number of subcarriers in each layer of the subframe included in the output of the phase reversal rotation unit 120 based on the demodulation result of the frame synchronization signal, and outputs the number of subcarriers in each layer to the subcarrier division unit 122. The calculation method is as described in the first embodiment.

[0100] Figure 14 is a block diagram illustrating an example of the subframe 1 demodulation unit 110 according to the second embodiment. The subframe 1 demodulation unit 110 consists of an FFT unit 144, an equalization processing unit 146, a frequency de-IL unit 148, a time de-IL unit 150, a subframe synthesis unit 152, an error correction unit 154, an energy de-diffusion unit 156, and a time adjustment unit 158.

[0101] The FFT unit 144 takes the synchronized signal input to the subframe 1 demodulation unit 110, performs symbol timing synchronization to remove GI, performs FFT processing to convert the time-domain signal into a frequency-domain signal, and outputs the subcarrier. The equalization processing unit 146 performs frequency equalization processing on the input subcarrier.

[0102] The frequency de-IL unit 148 performs frequency deinterleaving. The time de-IL unit 150 performs time deinterleaving. The subframe synthesis unit 152 synthesizes the input from the time de-IL and the input from the time adjustment unit. The error correction unit 154 performs LDPC decoding and BCH decoding on the synthesized signal. The energy despreading unit 156 calculates the exclusive OR of the signal after LDPC decoding and BCH decoding with a predetermined spread sequence and outputs the calculated sequence.

[0103] The time adjustment unit 158 ​​receives subcarriers of each layer from the subcarrier splitting unit 122 of the TMCC demodulation unit 108 and parameters from the parameter extraction unit 132 of the TMCC demodulation unit 108. Based on the input parameters, the time adjustment unit 158 ​​adjusts the output timing of the subcarriers of each layer and outputs the subcarriers to the subframe synthesis unit 152.

[0104] The frequency de-IL section 148, time de-IL section 150, subframe synthesis section 152, error correction section 154, and energy dediffusion section 156 constitute the demodulation section 160 of each layer. The time adjustment section 158 may also be included within the subframe synthesis section 152 of each layer.

[0105] The output timing adjusted by the time adjustment unit 158 ​​is the timing at which the subcarriers of each layer necessary for error correction by the error correction unit 154 are output from the time de-IL unit 150. Since the signals of each layer are time-interleaved, it is necessary to match the timing of the OFDM symbol received at the latest time. For example, if the time interleaving depth is the length of two frames, it is necessary to wait for the length of two frames. The time interleaving depth can be determined from the parameters input from the parameter extraction unit 132. The output timing adjusted by the time adjustment unit 158 ​​may also be adjusted to include the difference between the delay due to processing by the TMCC demodulation unit 108 and the delay due to processing by the subframe 1 demodulation unit 110. This difference in processing delay may be measured in advance and stored in the time adjustment unit 158.

[0106] The block diagram of the subframe 2 demodulation unit 112 is the same as the block diagram of the subframe 1 demodulation unit 110, but with the time adjustment unit 158 ​​and subframe synthesis unit 152 removed. Since the processing of the other blocks is the same, the block diagram and explanation are omitted.

[0107] The receiving device according to the second embodiment calculates the number of remaining subcarriers in the TMCC section, separates those remaining subcarriers from the TMCC section, and receives them as a hierarchical signal of the subframe. As a result, the transmission capacity of the hierarchical signal is improved.

[0108] [Third Embodiment] The third embodiment is an embodiment that simultaneously achieves improved communication performance and improved transmission capacity of hierarchical signals as described in the first and second embodiments by time interleaving the subcarriers of each layer in the TMCC section.

[0109] Figures 15, 16, and 17 illustrate the image of the transmission order of the B layer of subframe 1 in the case of partial reception bandwidth according to the first embodiment. Figures 18, 19, and 20 illustrate the image of the transmission order of the B layer of subframe 1 in the case of partial reception bandwidth according to the third embodiment. The A layer will be explained later.

[0110] Figure 15 shows the subcarriers of subframe 1 after primary modulation of the B layer in the case of partial receiving bandwidth according to the first embodiment. As an example, Figure 15 shows the B layer subcarriers of subframe 1 of frame a and frame (a+1). a is an integer of 2 or more. The beginning portion of each frame (from the beginning, number of subcarriers C) B (Only a few minutes) is transmitted in the TMCC section, and the remaining portion is transmitted in the subframe section.

[0111] Figure 16 shows the subcarriers of subframe 1 before time interleaving in the case of partial reception bandwidth according to the first embodiment. Before time interleaving, each frame contains all of the subcarriers of the B layer of each subframe.

[0112] Figure 17 shows the frame configuration (after time interleaving) output from the B-layer time-division multiplexed frame constructor 24 of subframe 1 in the case of partial receiving bandwidth according to the first embodiment. Here, the depth of time interleaving is the duration of one frame. In this case, the subcarriers transmitted in the subframe section are time-interleaved in the range from 0 symbols to 1 frame's worth of symbols, depending on the frequency of the subcarriers.

[0113] On the other hand, the subcarriers in the B layer of the TMCC section are not time-interleaved. The more time-interleaved subcarriers there are, the worse the reception performance becomes.

[0114] Figure 18 shows the subcarriers of subframe 1 after primary modulation of layer B in the case of partial receiving bandwidth according to the third embodiment. The difference from Figure 15 (first embodiment) is the beginning portion of each frame (from the beginning, the number of subcarriers C B (only 2 minutes) and the central part (number of subcarriers C from the center) B The point is that the transmission (for only 2 minutes) takes place in the TMCC section.

[0115] Figure 19 shows the subcarriers of subframe 1 before time interleaving in the case of partial receiving bandwidth according to the third embodiment. Before time interleaving, each frame contains all of the subcarriers of the B layer of each subframe.

[0116] Figure 20 shows the frame configuration (after time interleaving) output from the time-division multiplexed frame constructor 24 of subframe 1 in the case of partial reception bandwidth according to the third embodiment. Compared to Figure 17 (first embodiment), the B layer transmitted in the TMCC section is different. The beginning portion of frame a is transmitted in frame a, and the middle portion of frame a is transmitted in frame (a+1). By transmitting the middle portion of frame a in frame (a+1), unnecessary waiting time is avoided when transmitting the TMCC of frame a. The subcarriers of the B layer in the TMCC section are also time-interleaved, improving reception performance compared to the case in Figure 17.

[0117] Figure 20 shows an example where the beginning portion of each frame after primary modulation is transmitted in the TMCC section of the current frame, and the middle portion of each frame is transmitted in the TMCC section of the next frame. However, both the beginning and middle portions of each frame may be transmitted in the TMCC section of the next frame, or both may be transmitted in the TMCC section of the current frame.

[0118] Figures 21 and 22 illustrate an example of a frame configuration according to a modification of the third embodiment in which the leading and central portions of each frame are transmitted in the TMCC section of the next frame. Figure 21 shows the subcarrier of subframe 1 before time interleaving in the B layer when partial reception bandwidth is present according to the modification of the third embodiment. Figure 22 shows the frame configuration (after time interleaving) output from the time-division multiplexed frame configuration unit 24 of subframe 1 in the B layer when partial reception bandwidth is present according to the modification of the third embodiment.

[0119] Figures 21 and 22 show examples where the leading and middle portions after primary modulation are transmitted in the TMCC section. However, other portions may be transmitted in the TMCC section, or one or more portions may be selected and transmitted in the TMCC section.

[0120] Figures 18 to 22 illustrate the example using subframe 1's B layer, but other layers or other subframes may also be used.

[0121] Furthermore, it is possible to set different time interleaving depths for each layer.

[0122] Regarding the A layer, the number of subcarriers in the TMCC section is less than the number of OFDM symbols. Therefore, as shown in Figure 18, the beginning and middle portions can be transmitted in the TMCC section, but the effect is relatively small. For this reason, the B layer was used as an example instead of the A layer for this explanation.

[0123] [Transmitting device according to the third embodiment] In the first embodiment, when there is no partial receiving band as shown in Figure 4, the number of subcarriers of each layer occupying the TMCC section is less than 1 OFDM symbol, and the number of subcarriers that are not time-interleaved is small. When there is a partial receiving band as shown in Figure 11, the number of subcarriers of each layer of the partial receiving band occupying the TMCC section is less than 1 OFDM symbol, and the number of subcarriers that are not time-interleaved is small.

[0124] On the other hand, the number of subcarriers in each layer of the non-partial reception band within the TMCC interval can be one symbol or more. In that case, the number of subcarriers that are not time-interleaved is large. That is, the number of subcarriers that are not time-interleaved in the non-partial reception band (layers B to H) when a partial reception band is present can be large.

[0125] Figure 23 is a block diagram illustrating an example of the subframe section generation units 18, 20 and Lch separation unit 22 of the transmission device according to the third embodiment. Parts corresponding to the first embodiment shown in Figure 3 are given the same reference numerals, and detailed explanations are omitted. The modulation unit in Figure 23 has a subframe division buffer unit 180 added to the modulation unit in Figure 3.

[0126] The subframe division unit 36 ​​receives the number of subcarriers for each layer of subframe 1 from the sub-carrier number calculation unit 38, and receives the signals after primary modulation from the primary modulation units 34a, 34b, ... 34h of each layer. Each signal after primary modulation corresponds to a subcarrier included in the OFDM symbol. The subframe division unit 36 ​​outputs only the number of subcarriers for each layer that were input to the TMCC section generation unit 16, and outputs the remaining subcarriers to the level adjustment units 40a, 40b, ... 40h of the same layer as the input layer. For example, if the number of subcarriers for layer A input from the sub-carrier number calculation unit 38 is C A Therefore, starting from the beginning of the input A-level subcarrier, the number of subcarriers C A The subcarrier is / 2, and the number of subcarriers C is the number of subcarriers from the center of the input A-level subcarrier. A The / 2 subcarrier is output to the subframe splitting buffer 180. The same process is performed for other layers.

[0127] The subframe splitting buffer unit 180 receives subcarriers from each layer from the subframe splitting unit 36. The subframe splitting buffer unit 180 receives subcarriers from each layer twice per frame and stores the signals. After one frame, i.e., after receiving subcarriers from a certain layer twice, it outputs the input signal to the TMCC section generation unit 16. For example, when the subframe splitting buffer unit 180 receives the subcarriers from the middle of frame (a-1) and the beginning of frame a of layer B, it outputs the input signal to the TMCC section generation unit 16.

[0128] The subframe splitting buffer unit 180 may receive a trigger signal from the TMCC section generation unit 16 and output a stored signal immediately after receiving the trigger signal.

[0129] In this example, the subframe splitting buffer 180 is described as receiving subcarriers from the beginning and the center of each layer twice per frame. However, it may also receive other parts or a different number of inputs. These may be predetermined or notified by a frame synchronization signal or the like.

[0130] Hierarchical signals transmitted in subframes are time-interleaved, but control signals are not. The transmitting device according to the third embodiment has a subframe division buffer 180, which allows the hierarchical signals to be divided and transmitted using the remaining subcarriers in the TMCC section, thus enabling time interleaving. This makes it possible to simultaneously improve communication performance and the transmission capacity of hierarchical signals as described in the first and second embodiments.

[0131] [Fourth Embodiment] Figure 24 is a block diagram illustrating an example of the TMCC demodulation unit 108 of the receiver according to the fourth embodiment. Parts corresponding to Figure 13 (second embodiment) are given the same reference numerals, and detailed explanations are omitted. The TMCC demodulation unit 108 in Figure 24 has a subcarrier splitting buffer unit 184 added to the TMCC demodulation unit 108 in Figure 13.

[0132] The subcarrier splitting unit 122 splits a portion of the input subcarrier after phase reversal based on the value input from the subframe subcarrier number calculation unit 124, outputs the split portion of the subcarrier to the subcarrier splitting buffer unit 184, and outputs the remaining subcarrier to the carrier synthesis unit 126.

[0133] The subcarrier splitting buffer unit 184 extracts the number of subcarriers C from the subcarrier splitting unit 122 for each frame. B Input and store the subcarrier for each minute. Also, for each frame, the first half of the input subcarrier (C B ( / 2) and the latter half of the subcarrier of the subcarrier input one frame earlier (C B The output ( / 2) is sent to the time adjustment unit 158 ​​of the subframe 1 demodulation unit 110.

[0134] The subcarrier splitting buffer section 184 may also be included in the subframe demodulation sections 110 and 112.

[0135] The subcarrier splitting buffer unit 184 may change its processing based on the information contained in the demodulation result of the frame synchronization signal. For example, for each frame, the subcarrier (C) of the leading part of the subcarrier input in that frame may be split. B / 3) and the central subcarrier of the subcarrier input one frame earlier (C B / 3) and the end portion of the subcarrier input two frames ago (C B / 3) may be output to the subframe demodulation units 110 and 112.

[0136] The receiving device according to the fourth embodiment receives the remaining subcarriers (time-interleaved) in the TMCC section as a hierarchical signal. This makes it possible to simultaneously improve communication performance and the transmission capacity of the hierarchical signal described in the first and second embodiments.

[0137] [Fifth Embodiment] Figure 25 is a diagram illustrating an example of a frame configuration with partial receiving bandwidth according to the fifth embodiment. The difference from Figure 22 (third embodiment) is that the number of subcarriers in the TMCC of the (a+1)th frame is different. Due to changes in transmission parameters such as the number of information bits transmitted in the TMCC and the number of repetitions of the repetition code, the number of subcarriers in the TMCC may differ from frame to frame, and therefore the number of remaining subcarriers in the TMCC section may differ from frame to frame. Figure 25 shows an example where the number of repetitions of the TMCC repetition code has been changed from 2 to 1. As a result, it is not possible to transmit all of the B-layer subcarriers of subframe 1 of frame a, which would normally be transmitted in the TMCC section of the (a+1)th frame. The number of subcarriers that cannot be transmitted is C B_no Let's assume that.

[0138] The configuration of the transmitting device according to the fifth embodiment is the same as that of the transmitting device according to the first embodiment. The modulation section of the TMCC section generation unit according to the fifth embodiment is the same as the modulation section of the TMCC section generation unit 16 according to the first embodiment (Figure 10). Referring to Figure 10, the subcarrier synthesis section 84 of the modulation section of the TMCC section generation unit 16 according to the fifth embodiment will be described. The processing of the other parts is the same as the processing in Figure 10.

[0139] The subcarrier combining unit 84 combines the signal input from the carrier modulation unit 82 and the signal input from the subframe section generation unit 18. If the number of combined signals exceeds the number of subcarriers that can be transmitted in the TMCC section, the subcarrier combining unit 84 combines only the number of subcarriers that can be transmitted and discards the remaining subcarriers. For example, the subcarriers to be discarded are those with the last C among the subcarriers input from the subframe section generation unit. B_no It will be used as a subcarrier for minutes.

[0140] On the other hand, the opposite case shown in Figure 25 can also occur. That is, the number of repetitions of the TMCC repeat code changes from 1 to 2. This allows all of the B-layer subcarriers of subframe 1 of frame a, which would normally be transmitted in the TMCC section of frame (a+1), to be transmitted, and furthermore, the number of subcarriers CB_no This C can transmit subcarriers for a certain number of minutes. B_no A dummy subcarrier is transmitted as a subcarrier for the duration of the subcarrier. A dummy subcarrier is a subcarrier with a predetermined specific amplitude and phase. Alternatively, instead of a dummy subcarrier, the beginning of the B-layer subcarrier transmitted in the same TMCC section is C B_no You may send a subcarrier of minutes (repetition).

[0141] The subcarrier synthesis unit 84 may recognize the timing of changes in the parameters transmitted by the TMCC based on the countdown_index (transmission parameter switching index), which is part of the information transmitted by the TMCC, and may change the processing of the remaining subcarriers in the TMCC section at that switching timing. When switching the parameters transmitted by the TMCC, the transmission parameter switching index is counted down, decreasing by 1 each frame from 31 frames before the switch, and current information and next information are transmitted alternately. After 0, it returns to 31. The switching timing is synchronized with the next frame that outputs 0. That is, the new transmission parameters are applied from the frame in which the index returns to 1. Based on this information, the subcarrier synthesis unit 84 may calculate the remaining subcarriers after the switching timing and transmit the subcarriers of the subframe using those subcarriers, or it may repeat the TMCC subcarriers in the frames before and after the switch instead of sending the subcarriers of the subframe using the remaining subcarriers.

[0142] The number of bits in the control signal transmitted in one frame is not always the same and may vary from frame to frame. In such cases, it may be impossible to transmit the required number of bits, or the required number of bits may be insufficient. The transmitting device according to the fifth embodiment performs the following actions: thinning out the subcarriers of the hierarchical signal and then combining them with the subcarriers of the control signal; adding dummy subcarriers to combine the subcarriers of the hierarchical signal and the subcarriers of the control signal; or repeating a portion of the subcarriers of the hierarchical signal and combining them with the subcarriers of the control signal. As a result, even if the number of remaining subcarriers in the TMCC section differs from frame to frame, these subcarriers can be effectively utilized, thereby improving the transmission capacity of the hierarchical signal.

[0143] [Sixth Embodiment] The receiving device of the sixth embodiment will be described using the frame configuration (fifth embodiment) shown in Figure 25. The configuration of the receiving device according to the sixth embodiment is the same as the configuration of the receiving device according to the second embodiment. The configuration of the TMCC demodulation unit according to the sixth embodiment is the same as the configuration of the TMCC demodulation unit 108 according to the fourth embodiment shown in Figure 24. The configuration of the subframe 1 demodulation unit according to the sixth embodiment is the same as the configuration of the subframe 1 demodulation unit 110 according to the second embodiment shown in Figure 14. In the (a+1)th frame of Figure 25, the subcarrier that should originally be transmitted in the TMCC section is C B_no It is short by [number] minutes. Referring to Figures 24 and 14, the handling of the receiving device in such a case will be explained. Note that some parts of the explanation regarding Figures 24 and 13, which are the same as those described above, will be omitted.

[0144] The subframe subcarrier number calculation unit 124 in Figure 24 calculates the number of subcarriers for each layer of the subframe included in the output of the phase reversal rotation unit 120 based on the demodulation result of the frame synchronization signal, and outputs the number of subcarriers for each layer to the subcarrier division unit 122. The subframe subcarrier number calculation unit 124 also has a storage unit that stores the number of subcarriers for each layer calculated one frame earlier. The subframe subcarrier number calculation unit 124 also has a calculation unit that calculates the difference between the number of subcarriers for each layer and the stored number of subcarriers for each layer, and outputs this difference to the subframe demodulation units 110 and 112.

[0145] The time adjustment unit 158 ​​in Figure 13 receives the number of subcarriers for each layer and the difference in the number of subcarriers for each layer from the previous frame, input from the subcarrier splitting unit 122 of the TMCC demodulation unit 108, inputs parameters from the parameter extraction unit 132 of the TMCC demodulation unit 108, and outputs the subcarriers for each layer to the subframe synthesis unit 152 after adjusting their output timing based on the input parameters.

[0146] The subframe merging unit 152 merges the input from the time-de-IL unit 150 and the input from the time adjustment unit 158. If the difference in the number of subcarriers at each layer from the previous frame is negative (i.e., there are not enough subcarriers that should be received), the subframe merging unit 152 generates dummy subcarriers to the extent that there are not enough. The likelihood of the dummy subcarriers is set to, for example, 0. If the difference in the number of subcarriers at each layer from the previous frame is positive (i.e., there are fewer subcarriers than should be received), the subframe merging unit 152 generates dummy subcarriers to the extent that there are not enough. B_no (If there is only one extra subcarrier) The last subcarrier C among the subcarriers input from the time adjustment unit 158 B_no It discards the last subcarrier C among the subcarriers input from the time adjustment unit 158. B_no and the leading subcarrier C B_no The two are synthesized, and the resulting subcarrier is taken from the beginning C B_no Replace it with the subcarrier.

[0147] Note that the sub-frame synthesizing unit 152 may recognize the timing when the parameters transmitted by TMCC are changed based on the countdown_index (transmission parameter switching index), which is part of the information transmitted by TMCC, and change the processing for the remaining sub-carriers in the TMCC section at that switching timing. Based on this information, the sub-frame synthesizing unit 152 may calculate the number of remaining sub-carriers in the TMCC section after the switching timing as the processing for the remaining sub-carriers in the TMCC section, and process to receive the sub-carriers of the sub-frame with that number of sub-carriers. Alternatively, the sub-frame synthesizing unit 152 may receive the sub-carriers of the TMCC section as repetitions of the TMCC sub-carriers instead of receiving the sub-carriers of the sub-frame with the remaining sub-carriers in the frames before and after the switching, and perform iterative decoding and demodulation.

[0148] The receiving apparatus according to the sixth embodiment calculates the number of remaining sub-carriers in the TMCC section and receives the hierarchical signal with the remaining sub-carriers. Therefore, even when the number of remaining sub-carriers in the TMCC section differs for each frame, the sub-carriers can be effectively utilized, and the transmission capacity of the hierarchical signal can be improved.

[0149] [Embodiment 7] FIG. 26 is a diagram for explaining an example of the segment configuration according to the seventh embodiment. As shown in FIG. 26, Segment No. 0 is allocated to the central frequency band. The next segment number is allocated to two frequency bands adjacent to the frequency band to which the segment number is allocated. Note that the younger segment number is allocated to the higher frequency band of the two frequency bands.

[0150] FIG. 27 is a diagram for explaining an example of a frame configuration in the case of no partial reception band according to the seventh embodiment. The difference between the frame configuration according to the seventh embodiment and the frame configuration according to the first embodiment (FIG. 4) is the frequency arrangement of the A layer in subframe 1. In the first embodiment (FIG. 4), in the A layer of subframe 1, segment No. 0 is assigned to the highest frequency band, and then segments No. 1, No. 2,... are assigned in order of higher frequency bands. In the seventh embodiment (FIG. 27), in the A layer of subframe 1, segment No. 0 is assigned to the central frequency band, and segments No. 1, No. 2,... are assigned in order of a higher frequency band and a lower frequency band adjacent to the assigned band.

[0151] The configuration of the transmission device according to the seventh embodiment is the same as the configuration of the transmission device according to the first embodiment. The configuration of the divided sub-carrier number calculation unit of the subframe section generation unit according to the seventh embodiment is the same as the configuration of the divided sub-carrier number calculation unit 38 of the subframe section generation units 18 and 20 according to the first embodiment shown in FIG. 3. An example of the calculation method of the divided sub-carrier number calculation unit 38 according to the seventh embodiment is shown.

[0152] Number of information bits of TMCC: K T Number of parity bits of BCH code: P o (=168) Number of information bits of LDPC code: K i (=252) Number of parity bits of LDPC code: P L (=972,2196) Number of repetition code times: R Modulation multilevel number: M(=1 (BPSK), 2 (QPSK)) Signal (sub-carrier number) N after primary modulation of information bits of TMCC transmitted in one frame TMCC_MOD Is expressed by Equation 15.

[0153] N TMCC_MOD =ceil((K T +P o ) / K i )×(K i +PL )×R / M formula 15 Number of subcarriers per segment in TMCC: C seg (=216(8k),432(16k),864(32k)) Number of pilots per segment in TMCC: C P (=4,36,72,144,288) Number of Lch per segment of TMCC: C L (=4,8,16) Number of segments: S (=35) Number of primary modulated signals C that can be transmitted in one OFDM symbol in a TMCC section TMCC_CAP This is expressed by equation 16.

[0154] C TMCC_CAP =(C seg -C p -C L )×S Equation 16 The number of OFDM symbols Os3 in the TMCC section transmitted in one frame is expressed by Equation 17.

[0155] Os3=ceil(N TMCC_MOD / C TMCC_CAP ) Equation 17 The total number of subcarriers C across all layers is output from the subframe division unit 36 ​​of the subframe interval generation unit to the TMCC interval generation unit 16. all_lay This is calculated as shown in Equation 18.

[0156] C all_lay =Os3×C TMCC_CAP -N TMCC_MOD =ceil(N TMCC_MOD / C TMCC_CAP )×C TMCC_CAP -N TMCC_MOD =ceil((ceil((K T +P o ) / K i )×(K i +P L )×R / M) / ((C seg -C p -C L)×S))×((C seg -C p -C L )×S)-(ceil((K T +P o ) / K i )×(K i +P L )×R / M) Equation 18 Number of segments in the X hierarchy of subframe 1: S 1X (X represents the hierarchy from A to H) Number of subcarriers C in the TMCC section that can be transmitted with the number of segments in layer A of subframe 1 TMCC_1A This is calculated as shown in Equation 19.

[0157] C TMCC_1A =(C seg -C p -C L )×S 1A formula 19 Number of subcarriers C in the TMCC section that can be transmitted with the number of segments in layer B of subframe 1 TMCC_1B This is calculated as shown in Equation 20.

[0158] C TMCC_1B =(C seg -C p -C L )×S 1B formula 20 S is the number of segments with lower frequencies in the B layer of subframe 1. 1B_LOW This is calculated as shown in Equation 21.

[0159] S 1B_LOW =ceil(S 1B / 2) Equation 21 S is the number of higher frequency segments in the B layer of subframe 1. 1B_UP This is calculated as shown in Equation 22.

[0160] S 1B_UP =S 1B -ceil(S 1B / 2) Equation 22 C all_lay ≤(C seg -C p -C L )×S1B_UP In this case, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the A layer of sub-frame 1 to the TMCC interval generation unit 16 is 0, and the number of sub-carriers output from the B layer to the TMCC interval generation unit 16 is C all_lay is.

[0161] (C seg -C p -C L )×S 1B_UP <C all_lay ≦(C seg -C p -C L )×(S 1B_UP +S 1A ) In this case, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the A layer of sub-frame 1 to the TMCC interval generation unit 16 is C all_lay -(C seg -C p -C L )×S 1B_UP is, and the number of sub-carriers output from the B layer to the TMCC interval generation unit 16 is (C seg -C p -C L )×S 1B_UP is.

[0162] (C seg -C p -C L )×(S 1B_UP +S 1A )<C all_lay In this case, in the sub-frame division unit 36 of the sub-frame interval generation unit, the number of sub-carriers output from the A layer of sub-frame 1 to the TMCC interval generation unit 16 is C TMCC_1A is, and the number of sub-carriers output from the B layer to the TMCC interval generation unit 16 is C all_lay -C TMCC_1A is.

[0163] Hereinafter, the C layer, D layer, E layer, F layer, G layer, and H layer can be calculated in the same manner.

[0164] Note that the number of segments used by each hierarchical level is not necessarily an integer; it may be an integer multiple of 1 / 3 of a segment, or any other number.

[0165] In this example, the subcarriers generated by the carrier modulation unit 82 of the TMCC section generation unit 16 are frequency-arranged in ascending order of frequency. However, they may also be frequency-arranged in ascending order of frequency, or alternately from the middle (the center frequency of segment No. 0) to the lower and higher frequencies, or any other arrangement method may be used.

[0166] The same calculation can be performed even if a partial receiving bandwidth is present.

[0167] Similar to the subcarrier count calculation unit 38 of the modulator, the subframe subcarrier count calculation unit 124 of the demodulation unit can calculate the number of subcarriers for each layer of the subframe included in the output of the phase reversal rotation unit 120.

[0168] The transmitting device according to the seventh embodiment provides the same effects and advantages as the transmitting devices according to the first, third, and fifth embodiments.

[0169] Each component of the transmitting and receiving devices may be implemented in software by a CPU, rather than being implemented by multiple hardware blocks.

[0170] It should be noted that the present invention is not limited to the embodiments described above, and the components can be modified and implemented in practice without departing from the spirit of the invention. Furthermore, various inventions can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiments. Moreover, components from different embodiments may be appropriately combined. [Explanation of Symbols]

[0171] 14...Frame synchronization signal section generation unit, 16...TMCC section generation unit, 18,20...Subframe section generation unit, 22...Lch separation unit, 24...Time-division multiplexed frame configuration unit, 36...Subframe division unit, 38...Division subcarrier number calculation unit.

Claims

1. A subframe modulation means that performs primary modulation using Phase Shift Keying (PSK) or Quadrature Amplitude Modulation (QAM) and secondary modulation using Orthogonal Frequency Division Multiplexing (OFDM) for one or more hierarchical signals used in a broadcasting system, The system includes a control signal modulation means that performs primary modulation using PSK or QAM and secondary modulation using OFDM for a control signal used for at least one of synchronization and control in broadcast transmission, independently of the hierarchical signal. The subframe modulation means further comprises a subframe division means, The control signal modulation means further comprises a subcarrier synthesis means, The subframe splitting means outputs one or more subcarriers from the multiple subcarriers of the one or more hierarchical signals after primary modulation to the subcarrier combining means. The subcarrier synthesis means frequency multiplexes one or more subcarriers of the control signal after primary modulation and one or more subcarriers input from the subframe division means to generate one OFDM symbol. A transmitting device that transmits the output of the subframe modulation means and the output of the control signal modulation means by time-division multiplexing within a frame.

2. The transmitting device according to claim 1, further comprising a subframe division means for calculating the number of subcarriers that can be output from the subframe division means to the subcarrier synthesis means.

3. The transmitting device according to claim 1, further comprising a subframe splitting buffer that stores the one or more subcarriers output by the subframe splitting means and outputs the one or more stored subcarriers to the subcarrier combining means.

4. The aforementioned subcarrier synthesis means is If the number of subcarriers input from the subframe division means is less than the number of subcarriers that the transmitting device can transmit, then the number of subcarriers is thinned out and then frequency multiplexed with the number of subcarriers of the control signal after primary modulation. The transmitting device according to claim 1, claim 2, or claim 3, wherein when the number of one or more subcarriers input from the subframe division means is greater than the number of subcarriers that the transmitting device can transmit, the transmitting device frequency multiplexes one or more subcarriers of the control signal after primary modulation with one or more subcarriers input from the subframe division means and a dummy subcarrier, or repeats a part of the one or more subcarriers input from the subframe division means and frequency multiplexes it with one or more subcarriers of the control signal after primary modulation.

5. Control signal demodulation means for demodulating control signals used for at least one of synchronization and control in broadcast transmission, It includes a subframe demodulation means for demodulating a subframe modulated signal containing one or more hierarchical signals used in a broadcasting system, The control signal demodulation means further includes subcarrier splitting means, The subframe demodulation means further comprises a subframe synthesis means, The subcarrier splitting means splits the multiple subcarriers included in the OFDM symbol of the control signal after equalization processing into subcarriers of the control signal and subcarriers of the subframe signal, and outputs the subcarriers of the subframe signal to the subframe synthesis means. The subframe synthesis means is a receiving device that synthesizes the subcarriers of the hierarchical signal after equalization processing with the subcarriers of the subframe signal input from the subcarrier splitting means.

6. The receiving device according to claim 5, further comprising: a time adjustment means connected between the subframe combining means and the subcarrier splitting means, which adjusts the timing at which the subcarriers of the subframe signal are input to the subframe combining means.

7. The receiving device according to claim 6, further comprising a subcarrier splitting buffer means for splitting the subcarriers of a plurality of subframes output from the subcarrier splitting means and outputting them to the time adjustment means.

8. The subcarrier splitting buffer means is A dummy subcarrier is added to the subcarrier of the input subframe and output to the time adjustment means. Discard a portion of the subcarriers of the input subframe and output it to the time adjustment means, or The receiving device according to claim 7, which combines a portion of the subcarrier of an input subframe with another portion, replaces the portion or the other portion with the combined subcarrier, and outputs it to the time adjustment means.

9. A subframe modulation means that performs primary modulation using Phase Shift Keying (PSK) or Quadrature Amplitude Modulation (QAM) and secondary modulation using Orthogonal Frequency Division Multiplexing (OFDM) for one or more hierarchical signals used in a broadcasting system, A transmission method for a transmitting device having a control signal modulation means that performs primary modulation with PSK or QAM and secondary modulation with OFDM on a control signal used for at least one of synchronization and control in broadcast transmission, independently of the hierarchical signal, The subframe modulation means outputs one or more subcarriers of the one or more hierarchical signals after the first modulation to the control signal modulation means. The control signal modulation means frequency multiplexes one or more subcarriers of the control signal after primary modulation and one or more subcarriers of the one or more hierarchical signals after primary modulation to generate one OFDM symbol. A transmission method that transmits the output of the subframe modulation means and the output of the control signal modulation means by time-division multiplexing within a frame.

10. Control signal demodulation means for demodulating control signals used for at least one of synchronization and control in broadcast transmission, A receiving method for a receiving device having subframe demodulation means for demodulating a subframe modulated signal that includes one or more hierarchical signals used in a broadcasting system, The control signal demodulation means divides the multiple subcarriers included in the OFDM symbol of the control signal after equalization processing into subcarriers of the control signal and subcarriers of the subframe signal, and outputs the subcarriers of the subframe signal to the subframe demodulation means. A receiving method comprising using the subframe demodulation means to combine the subcarriers of the hierarchical signal after equalization processing with the subcarriers of the subframe signal input from the control signal demodulation means.

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