Transmitter and receiver

Abstract

To provide a method enabling the increase of transmission capacity when implemented in combination with existing services.SOLUTION: A transmitting device is provided, comprising : bit interleaving portions 5231 and 3231 which generate a first bit sequence of a first data stream and a second bit sequence of a second data stream by performing bit interleaving, respectively; a mapping portion 5241 which generates a first modulation symbol sequence by mapping the first bit sequence; a mapping portion 3241 which generates a second modulation symbol sequence by mapping the second bit sequence; an addition portion 3261 which generates a multiplexed signal by superimposing the first and second modulation symbol sequences; and a TMCC / AC signal generation portion 5091 which generates a control signal from control information indicating a multiplexing method.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to wireless transmission technology.

Background Art

[0002] In Japanese terrestrial television broadcasting, analog broadcasting ended in July 2011, and it was completely shifted to digital broadcasting. In Japanese terrestrial television broadcasting, HDTV services are provided using the ISDB-T (ISDB-Terrestrial) system as the transmission standard. The ISDB-T system adopts the OFDM (Orthogonal Frequency Division Multiplexing) system (Non-Patent Document 1).

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, in wireless transmission, an increase in capacity is required. Therefore, an object of the present disclosure is to provide a transmission device, a reception device, a transmission method, and a reception method that can increase the transmission capacity compared to the current service without using other frequency bands when implemented in combination with the current service in wireless transmission.

Means for Solving the Problems

[0005] To achieve the above objective, a transmitting device according to one aspect of the present disclosure transmits a plurality of data sequences, including a first data sequence of a first hierarchy and a second data sequence of a second hierarchy, by multiplexing and superimposing coding, comprising: a first bit interleaving unit that generates a first bit sequence of the first data sequence by bit interleaving the first data sequence; a second bit interleaving unit that generates a second bit sequence of the second data sequence by bit interleaving the second data sequence; a first mapping unit that generates a first modulation symbol sequence of the first data sequence by mapping the first bit sequence of the first data sequence; and a mapping unit that maps the second bit sequence of the second data sequence. The system comprises: a second mapping unit that generates a second modulation symbol sequence of the second data sequence by pinging; a superposition unit that generates a multiplexed signal by superimposing the first modulation symbol sequence and the second modulation symbol sequence at a predetermined amplitude ratio; a control signal generation unit that generates a control signal from control information indicating the multiplexing method; and a transmission unit that transmits the multiplexed signal and the control signal, wherein the control signal is transmitted by the transmission unit without being superimposed on other signals, the control information includes information indicating that the second data sequence is multiplexed in the multiplexed signal, and the information is indicated by a flag set at a bit position in a predetermined bit array that is not used in the first communication standard and is used in a second communication standard different from the first communication standard. [Effects of the Invention]

[0006] According to the above-described transmitting device, when implemented in combination with existing services in wireless transmission, it is possible to increase the transmission capacity compared to existing services without using other frequency bands. [Brief explanation of the drawing]

[0007] [Figure 1] This figure shows the configuration of the transmitting device 3000 in Embodiment 1. [Figure 2] This figure shows the configuration of the hierarchical processing unit 3041 in Embodiment 1. [Figure 3] This figure shows a part of the definition of the TMCC signal in Embodiment 1. [Figure 4] This figure shows the configuration of an existing ISDB-T receiving device 3300 in Embodiment 1. [Figure 5] This figure shows the configuration of the multi-layer TS playback unit 3331 in Embodiment 1. [Figure 6] This figure shows the configuration of the FEC decoding unit 3333 in Embodiment 1. [Figure 7] This figure shows the configuration of the receiving device 3500 in Embodiment 1. [Figure 8] This figure shows the configuration of the FEC decoding unit 3533 in Embodiment 1. [Figure 9] This figure shows the configuration of the transmitting device 3600 in Embodiment 2. [Figure 10] This figure shows the configuration of the receiving device 3800 in Embodiment 2. [Figure 11] This figure shows the configuration of the transmitting device 4000 in Embodiment 3. [Figure 12] This figure shows the configuration of the receiving device 4600 in Embodiment 3. [Figure 13] This figure shows the configuration of the transmitting device 4100 in Embodiment 4. [Figure 14] This diagram shows the configuration of the hierarchical processing unit 4141 in Embodiment 4. [Figure 15] This figure shows a part of the definition of the TMCC signal in Embodiment 4. [Figure 16] This figure shows the configuration of the receiving device 4700 in Embodiment 4. [Figure 17] This figure shows the configuration of the transmitting device 4200 in Embodiment 5. [Figure 18] This figure shows the segment configuration in Embodiment 5. [Figure 19] This figure shows the configuration of the receiving device 4800 in Embodiment 5. [Figure 20]This is a diagram showing the configuration of the transmission device 4400 in Embodiment 6. [Figure 21] This is a diagram showing the SP signal arrangement pattern when the selection signal is "1" in Embodiment 6. [Figure 22] This is a diagram showing the configuration of the reception device 4900 in Embodiment 6. [Figure 23] This is a diagram showing the configuration of the transmission device 5000 in the ISDB-T system. [Figure 24] This is a diagram showing the configuration of the hierarchical processing unit 5041 in the ISDB-T system. [Figure 25] This is a diagram showing the configuration of the frequency interleaving unit 5071 in the ISDB-T system. [Figure 26] This is a diagram showing the segment configuration of the ISDB-T system.

Embodiments for Carrying out the Invention

[0008] FIG. 23 is a diagram showing the configuration of the transmission device 5000 in the ISDB-T system. The transmission device 5000 includes a TS (Transport Stream) remultiplexing unit 5011, an RS (Reed-Solomon) encoding unit 5021, a hierarchical division unit 5031, hierarchical processing units 5041-A to C, a hierarchical synthesis unit 5051, a time interleaving unit 5061, a frequency interleaving unit 5071, a pilot signal generation unit 5081, a TMCC (Transmission Multiplexing Configuration Control) / AC (Auxiliary Channel) signal generation unit 5091, a frame configuration unit 5101, an OFDM signal generation unit 5111, a D / A conversion unit 5121, and a frequency conversion unit 5131.

[0009] The operation of the transmitting device 5000 is described below. Multiple TSs output from the MPEG-2 multiplexing unit (not shown) are input to the TS remultiplexing unit 5011 to arrange the TS packets in a manner suitable for signal processing on a data segment basis. The TS remultiplexing unit 5011 converts the data into a single TS in a burst signal format of 188 bytes using a clock four times the FFT (Fast Fourier Transform) sample clock. The RS encoding unit 5021 performs RS encoding and adds 16 bytes of parity to the 188 bytes of information. When performing hierarchical transmission, the hierarchical division unit 5031 performs hierarchical division into up to three systems (A hierarchy, B hierarchy, C hierarchy) according to the specified hierarchical information.

[0010] Figure 24 shows the configuration of the hierarchical processing unit 5041. The hierarchical processing unit 5041 comprises an energy diffusion unit 5201, a byte interleaving unit 5211, a convolutional coding unit 5221, a bit interleaving unit 5231, and a mapping unit 5241. The hierarchical processing unit 5041 primarily performs digital data processing such as error correction coding and interleaving, as well as carrier modulation, on the input hierarchical data. Error correction, interleaving length, and carrier modulation method are set independently for each hierarchical level.

[0011] In Figure 23, the hierarchical synthesis unit 5051 performs hierarchical synthesis of up to three sets of data (A hierarchy, B hierarchy, and C hierarchy) output from the hierarchical processing units 5041-A to C.

[0012] Figure 25 shows the configuration of the frequency interleaving unit 5071. The frequency interleaving unit 5071 comprises a segment division unit 5301, inter-segment interleaving units 5311-D and S, intra-segment carrier rotation units 5321-P, D and S, and intra-segment carrier randomization units 5331-P, D and S. In order to effectively utilize the error correction coding capability against electric field fluctuations and multipath interference in mobile reception, the time interleaving unit 5061 performs intra-segment convolution interleaving on the output from the hierarchical synthesis unit 5051, and the frequency interleaving unit 5071 performs inter-segment and intra-segment interleaving. In the frequency interleaving unit 5071, the segment division unit 5301 assigns data segment numbers 0 to 12 in the following order: partial reception unit, differential modulation unit (segment where carrier modulation is specified as DQPSK), and synchronous modulation unit (segment where carrier modulation is specified as QPSK, 16QAM, or 64QAM). Regarding the relationship between the hierarchical structure and data segments, the data segments of each hierarchical level are arranged sequentially in numerical order, and the hierarchical levels are designated as A, B, and C, starting from the hierarchical level containing the smallest data segment number. Even if the hierarchical levels are different, interleaving is performed between data segments belonging to the same type of modulation section.

[0013] In Figure 23, the pilot signal generation unit 5081 generates a pilot signal for synchronous regeneration. To assist the demodulation and decoding of the receiving device in hierarchical transmission where multiple transmission parameters are mixed, the TMCC / AC signal generation unit 5091 generates a TMCC signal, which is control information, and an AC signal, which is additional information. The frame configuration unit 5101 constructs an ISDB-T transmission frame from the information data output from the frequency interleaving unit 5071, the pilot signal for synchronous regeneration output from the pilot signal generation unit 5081, and the TMCC signal output from the TMCC / AC signal generation unit 5091.

[0014] Figure 26 shows the segment configuration of the ISDB-T system, using the synchronous modulation section (QPSK, 16QAM, 64QAM) of Mode 1 (FFT size of 2k) as an example. Instead of transmitting the scattered pilot signal (hereinafter referred to as SP signal: Scattered Pilot signal) as a pilot signal for synchronous regeneration for each subcarrier, it is transmitted in the frequency (subcarrier) direction and the time (symbol) direction at a carrier position where the carrier number k satisfies k = 3(n mod 4) + 12p (mod represents the modulo operation, and p is an integer) for each symbol with symbol number n. That is, as shown in Figure 26, the SP signal is repeatedly placed with a period of 4 symbols, and each symbol is shifted by 3 carriers. The SP signal placed in this way is modulated to binary with a specific pattern determined by its carrier position and transmitted. In addition, the carriers of the TMCC signal and AC signal are randomly placed in the frequency direction to reduce the effect of periodic dips in the transmission path characteristics due to multipath. In the ISDB-T system, information transmission signals are transmitted using a carrier that does not contain SP, TMCC, or AC signals, and are modulated using modulation schemes such as QPSK, 16QAM, or 64QAM.

[0015] In Figure 23, the OFDM signal generation unit 5111 inserts IFFT (Inverse FFT) and GI (Guard Interval) into the ISDB-T transmission frame configuration output from the frame configuration unit 5101, and outputs an ISDB-T digital baseband transmission signal. The D / A conversion unit 5121 performs D / A conversion on the ISDB-T digital baseband transmission signal output from the OFDM signal generation unit 5111, and outputs an ISDB-T analog baseband transmission signal. The frequency conversion unit 5131 performs frequency conversion on the ISDB-T analog baseband transmission signal output from the D / A conversion unit 5121 to frequency channel Y, and outputs an ISDB-T analog RF transmission signal from a transmitting antenna (Tx-1) not shown.

[0016] Incidentally, in recent years, there has been much discussion about UHDTV (Ultra HDTV) services, which have a resolution exceeding that of HDTV services. In order to realize UHDTV services with high bitrates, it is important to consider transmission methods that enable high-capacity transmission with higher frequency utilization efficiency than the ISDB-T method. As one method of performing high-capacity transmission without using other frequency bands while continuing the current broadcasting service using the ISDB-T method, a method is being considered that applies the LDM (Layered Division Multiplexing) method to the current ISDB-T broadcasting service to increase transmission capacity (Non-Patent Literature 2).

[0017] Non-patent document 2 assigns a high signal level to the transmission RF signal of the current ISDB-T broadcasting system and a low signal level to the transmission RF signal of the new broadcasting system (using the same RF frequency as the ISDB-T system). The former is called UL (Upper Level) and the latter is called LL (Lower Level), and the UL and LL transmission RF signals are added together and output from the transmitting antenna.

[0018] The receiving device compatible with the new broadcasting system first decodes the UL data from the received RF signal, and then uses the transmission path estimate to reconstruct the RF received signal as if it were transmitted using only UL. Then, by subtracting the reconstructed UL RF received signal from the received RF signal, it extracts the RF received signal as if it were transmitted using only LL, and decodes the LL data.

[0019] Furthermore, when receiving only UL signals, LL signals can be considered noise, and therefore no special processing such as reconstruction or subtraction is necessary. This also applies to existing receiving equipment compatible with current broadcasting using the ISDB-T system.

[0020] Non-patent document 2 examines the possibility of continuing the current ISDB-T broadcasting system and achieving high-capacity transmission without using other frequency bands by applying this LDM method.

[0021] However, in applying this LDM method, it is necessary to construct a system that allows receiving equipment compatible with the new broadcasting system to accurately decode UL and LL signals, while also eliminating any adverse effects on existing receiving equipment compatible with the current broadcasting system. Furthermore, it is necessary to construct a system that takes into account the possibility that, several years after the practical application of this LDM method, the current broadcasting system using ISDB-T (UL signal) will be discontinued, and only the new broadcasting system using the new broadcasting system (LL signal) will remain.

[0022] The inventions described below in Embodiments 1 to 6 were made to solve the above-mentioned problems, and aim to provide a transmitting device, transmitting method, receiving device, receiving method, integrated circuit, and program that newly use the LDM method for current broadcasting.

[0023] Each embodiment will be described in detail below with reference to the drawings.

[0024] (Embodiment 1) <Transmitting device and transmission method> Figure 1 shows the configuration of the transmitting device 3000 in Embodiment 1 of the present invention. Components that are the same as those in a conventional transmitting device are given the same reference numerals and their descriptions are omitted.

[0025] The transmitting device 3000 shown in Figure 1 has a configuration in which the hierarchical processing units 5041-A to C are replaced with hierarchical processing units 3041-A to C, compared to the conventional transmitting device 5000 shown in Figure 23.

[0026] The operation of the transmitting device 3000 is described below. Multiple TS signals for the new broadcasting system output from the MPEG-2 multiplexing unit (not shown) are input as LL signals to the hierarchical processing units 3041-A to C, respectively. On the other hand, multiple TS signals for the ISDB-T system are input as UL signals to the TS remultiplexing unit 5011, and the TS remultiplexing unit 5011, RS encoding unit 5021, and hierarchical division unit 5031 perform the same processing as the conventional transmitting device 5000 shown in Figure 23.

[0027] Figure 2 shows the configuration of the hierarchical processing unit 3041. Compared to the conventional hierarchical processing unit 5041 shown in Figure 24, this configuration adds an energy diffusion unit 3201, a BCH coding unit 3211, an LDPC coding unit 3221, a bit interleaving unit 3231, a mapping unit 3241, a power difference control unit 3251, an adder unit 3261, and a power normalization unit 3271.

[0028] In the hierarchical processing unit 3041 shown in Figure 2, when a UL signal is input from the hierarchical division unit 5031, the energy diffusion unit 5201, byte interleaving unit 5211, convolution coding unit 5221, bit interleaving unit 5231, and mapping unit 5241 perform the same processing as the conventional hierarchical processing unit 5041 shown in Figure 24.

[0029] When an LL signal is input, the energy spreading unit 3201 collects the data contained in one or more TS packets and stores timing information in the header as information bits, and performs energy spreading processing only on the information bits. The BCH coding unit 3211 performs BCH coding, and the LDPC coding unit 3221 performs LDPC coding. The bit interleaving unit 3231 performs bit interleaving differently from the bit interleaving unit 5231 of the ISDB-T system shown in Figure 2 in order to bring out the capabilities of LDPC coding. The mapping unit 3241 applies, for example, NUQAM (Non-Uniform QAM) as carrier modulation to increase capacity.

[0030] Based on the LL signal power instruction signal, the power of the carrier modulation signal (LL) output from the mapping unit 3241 is reduced to the power of the carrier modulation signal (UL) output from the mapping unit 5241.

[0031] The summing unit 3261 adds the carrier modulation signals (UL and LL) output from the mapping unit 5241 and the power difference control unit 3251.

[0032] Based on the LL signal power instruction signal, the power of the output signal of the summing unit 3261 is normalized so that it is the same power as the power of the carrier modulation signal (UL) output from the mapping unit 5241.

[0033] In the transmitter 3000 shown in Figure 1, the hierarchical combining unit 5051 and subsequent units operate in the same manner as the conventional transmitter 5000 shown in Figure 23. However, as will be described later using Figure 3 (part of the definition of the TMCC signal), the definition of the TMCC signal for the ISDB-T system is partially modified in order to apply the LDM method performed in the hierarchical processing unit 3041 shown in Figure 2.

[0034] Figure 3 shows a part of the definition of the TMCC signal. Figures 3(a) and 3(b) show the definitions of B110 to B121 in the TMCC signal in the ISDB-T system and in this embodiment 1, respectively. As shown in Figure 3(b), in this embodiment 1, B110, which was undefined (all "1") in the ISDB-T system, is changed as follows.

[0035] ·B110: "0" indicates LDM transmission is enabled, "1" indicates LDM transmission is disabled (ISDB-T system only). This allows receiving equipment compatible with the new broadcasting system to recognize the presence or absence of LDM transmission without adversely affecting existing ISDB-T receiving equipment.

[0036] When B110 is "0", B111 to B121, which were undefined (all "1") in the ISDB-T method in this embodiment 1, are changed as follows.

[0037] B111~B112: Represents the UL / LL signal power ratio, where "00" is 17.5dB, "01" is 20dB, "10" is 22.5dB, and "11" is 25dB. B113 / B114 / B115: Represents the carrier modulation mapping scheme for each layer LL signal, where "0" is 256NUQAM and "1" is 1024QAM. ·B116~B117 / B118~B119 / B120~B121: Represents the LDPC coding rate of each layer LL signal, where "00" is 1 / 2, "01" is 2 / 3, "10" is 3 / 4, and "11" is 5 / 6.

[0038] With the above configuration, the hierarchical synthesis unit 5051 and beyond operate in the same manner as the ISDB-T system, and by assigning control information related to LDM transmission to the bit group that was undefined in the TMCC signal of the ISDB-T system, adverse effects on existing receiving equipment compatible with current broadcasts can be eliminated.

[0039] Furthermore, in Non-Patent Document 2, the UL and LL transmitted RF signals are simply added together, resulting in an LDM-based transmission signal with poor accuracy. On the other hand, in Embodiment 1, LDM addition is not performed on the SP signal in particular, so the transmitted signal has good accuracy as an LDM-based signal. Therefore, both existing receiving devices compatible with current broadcasting and receiving devices compatible with new broadcasting systems can accurately estimate the transmission path. As a result, receiving devices compatible with new broadcasting systems can accurately decode the UL and LL signals.

[0040] <Existing ISDB-T receiving equipment and receiving methods> Figure 4 shows the configuration of an existing ISDB-T receiver 3300. The ISDB-T receiver 3300 in Figure 4 corresponds to the transmitter 5000 in Figure 23 and reflects the functions of the transmitter 5000.

[0041] The ISDB-T receiving device 3300 comprises a tuner unit 3305, an A / D conversion unit 3308, a demodulation unit 3311, a frequency deinterleaving unit 3315, a time deinterleaving unit 3321, a multi-layer TS playback unit 3331, an FEC decoding unit 3333, and a TMCC signal decoding unit 3335.

[0042] The operation of the ISDB-T receiver 3300 is described below. When an analog RF transmission signal is input from the receiving antenna Rx-1 to the signal transmitted from the transmitter 5000 in Figure 23, the tuner unit 3305 selectively receives the signal of the selected frequency channel (CH-Y) and down-converts it to a predetermined bandwidth. The A / D converter unit 3308 performs A / D conversion and outputs the digital received signal. The demodulation unit 3311 performs OFDM demodulation and outputs the mapping data (cell) of the equalized I·Q coordinates and the transmission path estimate to the frequency deinterleaving unit 3315, while also outputting the FFT output before equalization to the TMCC signal decoding unit 3335.

[0043] The TMCC signal decoding unit 3335 performs differential BPSK demodulation on each carrier where the TMCC signal shown in Figure 26 is located, using the pre-equalization FFT output from the demodulation unit 3311. The demodulation results collected for each segment are then decoded by majority vote to decode the TMCC signal. The decoded TMCC signal is output to the demodulation unit 3311, the frequency deinterleaving unit 3315, the time deinterleaving unit 3321, the multi-layer TS regeneration unit 3331, and the FEC decoding unit 3333, and each unit performs operations based on the decoded TMCC signal.

[0044] The frequency deinterleaving unit 3315 performs frequency deinterleaving on the equalized I·Q coordinate mapping data and transmission path estimates output from the demodulation unit 3311 for the partial reception unit, differential modulation unit, and synchronous modulation unit, respectively. The time deinterleaving unit 3321 performs time deinterleaving on the output from the frequency deinterleaving unit 3315.

[0045] Figure 5 shows the configuration of the multi-layer TS regeneration unit 3331. The multi-layer TS regeneration unit 3331 comprises a demapping unit 3401, a bit deinterleaving unit 3411, a depuncture unit 3421, and a TS regeneration unit 3431. The demapping unit 3401 performs demapping processing based on the mapping data of the equalized I·Q coordinates rearranged by the frequency deinterleaving unit 3315 and the time deinterleaving unit 3321, and the transmission path estimate. The bit deinterleaving unit 3411 performs bit deinterleaving, and the depuncture unit 3421 performs depuncture processing. The TS regeneration unit 3431 performs TS regeneration for each layer on the output of the depuncture unit 3421.

[0046] Figure 6 shows the configuration of the FEC decoding unit 3333. The FEC decoding unit 3333 comprises a Viterbi decoding unit 3441, a byte deinterleaving unit 3451, an energy dediffusion unit 3461, and an RS decoding unit 3471. For the output from the multi-layer TS regeneration unit 3331, the Viterbi decoding unit 3441 performs Viterbi decoding, the byte deinterleaving unit 3451 performs byte deinterleaving, the energy dediffusion unit 3461 performs energy dediffusion, and the RS decoding unit 3471 performs RS decoding.

[0047] Through the above operation, the ISDB-T receiver 3300 in Figure 4 outputs TS for each layer of the ISDB-T system, including error correction and decoding, for the signal transmitted from the transmitter 5000 in Figure 23. Note that the components of the ISDB-T receiver 3300 in Figure 4, excluding the tuner unit 3305, may be included as an integrated circuit 3341.

[0048] As shown in Figure 3, the new broadcasting system (LL signal) has lower power than the ISDB-T system (UL signal), ranging from 17.5 dB to 25 dB. Since the current ISDB-T broadcasting system requires a C / N of approximately 20 dB, the new broadcasting system (LL signal) will be buried at a power level below the noise at reception points near the required C / N. Therefore, adverse effects on existing ISDB-T receiving equipment can be eliminated.

[0049] Furthermore, since LDM addition is not performed on the SP signal, existing ISDB-T receivers can accurately estimate the transmission path, and as a result, accurately decode the ISDB-T signal (UL signal).

[0050] <Receiving device and receiving method> Figure 7 shows the configuration of the receiving device 3500 in Embodiment 1 of the present invention. The receiving device 3500 in Figure 7 corresponds to the transmitting device 3000 in Figure 1 and reflects the functions of the transmitting device 3000. Components that are the same as those in existing ISDB-T receiving devices are given the same reference numerals and their descriptions are omitted.

[0051] The receiving device 3500 has a configuration that differs from the ISDB-T receiving device 3300 shown in Figure 4, in that the TMCC signal decoding unit 3335 is replaced with a TMCC signal decoding unit 3535. Furthermore, it has an additional UL received signal reconstruction unit 3551, a delay unit 3553, a subtraction unit 3555, and an FEC decoding unit 3533.

[0052] The operation of the receiving device 3500 will be described below. When an analog RF transmission signal is input from the receiving antenna Rx-1 to the signal transmitted from the transmitting device 3000 in Figure 1, the tuner unit 3305, A / D converter 3308, demodulator 3311, frequency deinterleaving unit 3315, time deinterleaving unit 3321, multi-layer TS regeneration unit 3331, and FEC decoding unit 3333 operate in the same manner as the ISDB-T receiving device 3300 shown in Figure 4, and the FEC decoding unit 3333 outputs TS (UL decoded signals) for each layer of the ISDB-T system, including error correction decoding.

[0053] The TMCC signal decoding unit 3535 operates in essentially the same way as the TMCC signal decoding unit 3335 in Figure 4, but it also has the function of outputting the new broadcasting system bit group B110~B121 in the TMCC signal shown in Figure 3 to the UL received signal construction unit 3551 and the FEC decoding unit 3533.

[0054] Next, the UL received signal reconstruction unit 3551 uses the transmission path estimate and the UL decoded signal output from the FEC decoding unit 3333 to reconstruct the received signal (mapping data of the equalized I·Q coordinates) as if it were transmitted using only UL.

[0055] The delay unit 3553 delays the mapping data of the equalized I·Q coordinates output from the time deinterleaving unit 3321 to synchronize its timing with the output of the UL received signal reconstruction unit 3551. The subtraction unit 3555 subtracts the output of the UL received signal reconstruction unit 3551 from the output of the delay unit 3553 and outputs the received signal (mapping data of the equalized I·Q coordinates) as if transmitted only by LL.

[0056] Figure 8 shows the configuration of the FEC decoding unit 3533. The FEC decoding unit 3533 consists of a demapping unit 3561, a bit deinterleaving unit 3563, an LDPC decoding unit 3565, a BCH decoding unit 3567, an energy dediffusion unit 3569, and a TS regeneration unit 3571.

[0057] When the received signal (mapping data of the equalized I·Q coordinates) transmitted only via LL is input from the subtraction unit 3555, the demapping unit 3561 performs demapping, the bit deinterleaving unit 3563 performs bit deinterleaving, the LDPC decoding unit 3565 performs LDPC decoding, the BCH decoding unit 3567 performs BCH decoding, the energy despreading unit 3569 performs energy despreading, and the TS regeneration unit 3571 performs TS regeneration. Through these operations, the receiving device 3500 in Figure 7 outputs TS (LL decoded signals) for each layer of the new broadcasting system, including error correction decoding, for the signal transmitted from the transmitting device 5000 in Figure 23. Note that the components of the receiving device 3500 in Figure 7, excluding the tuner unit 3305, may be included as an integrated circuit 3541.

[0058] With the above configuration, the receiving device compatible with the new broadcasting system can detect control information related to LDM transmission assigned to the bit group that was undefined in the ISDB-T TMCC signal, and decode the UL signal and LL signal.

[0059] Furthermore, since LDM addition is not performed on the SP signal, the receiving device compatible with the new broadcasting system can accurately estimate the transmission path, and as a result, accurately decode the UL signal and LL signal.

[0060] (Embodiment 2) <Transmitting device and transmission method> Figure 9 shows the configuration of the transmitter 3600 in Embodiment 2 of the present invention. Components that are the same as those in the conventional transmitter and the transmitter of Embodiment 1 are given the same reference numerals and their descriptions are omitted.

[0061] The transmitter 3600 in Figure 9 has a configuration that adds a TMCC / AC signal generation unit (for LL) 3691, a power difference control unit 3251, an adder 3261, and a power normalization unit 3271 compared to the transmitter 3000 in Embodiment 1 shown in Figure 1.

[0062] The TMCC / AC signal generation unit (for LL) 3691 generates a TMCC signal, which is control information, and an AC signal, which is additional information, for use in LL. The generated TMCC signal may be the same as the information shown in Figure 3(b), or the number of configurable patterns may be increased by increasing the number of bits for each parameter (UL / LL signal power ratio, etc.). Alternatively, the number of parameter types may be increased. The power difference control unit 3251, the adder 3261, and the power normalization unit 3271 perform the same operations as in Figure 2 on the outputs of the TMCC / AC signal generation unit 5091 and the TMCC / AC signal generation unit (for LL) 3691.

[0063] Furthermore, if the TMCC / AC signal generation unit 5091 generates at least B110 (presence or absence of LDM transmission) from the information shown in Figure 3(b), a receiving device compatible with the new broadcasting system can easily detect whether or not LDM transmission is being performed. However, all or some of B110 to B121 may also be generated.

[0064] The frame configuration unit 5101 constructs an ISDB-T transmission frame from the information data output from the frequency interleaving unit 5071, the pilot signal for synchronous regeneration output from the pilot signal generation unit 5081, and the TMCC signal output from the power normalization unit 3271.

[0065] Other operations are the same as those of the transmitter 3000 in Embodiment 1 shown in Figure 1.

[0066] With the above configuration, by applying the LDM method of summing to TMCC as well, the number of bits in TMCC (for LL) can be increased, thereby enhancing the flexibility of the new broadcasting system. On the other hand, for existing ISDB-T receiving equipment, the received C / N of information data and TMCC signals can be observed at the same level, so the received C / N detection value using the TMCC signal becomes equivalent to the received C / N of information data, eliminating any adverse effects.

[0067] <Existing ISDB-T receiving equipment and receiving methods> The operation of the ISDB-T receiver 3300 in Figure 4 in response to the signal transmitted from the transmitter 3600 in Figure 9 is the same as the operation in response to the signal transmitted from the transmitter 3000 in Figure 1 in Embodiment 1.

[0068] The signal transmitted from the transmitter 3600 in Figure 9 undergoes LDM summing with respect to the TMCC, but the TMCC (LL signal) of the new broadcasting system has lower power than the TMCC (UL signal) of the ISDB-T system, ranging from 17.5 dB to 25 dB. Since the required C / N for the TMCC of the current ISDB-T broadcasting system is approximately 10 dB, the TMCC (LL signal) of the new broadcasting system will be buried at a power level below the noise at reception points near the required C / N. Therefore, adverse effects on existing ISDB-T receiving equipment can be eliminated. Note that the range of the UL / LL signal power ratio for the TMCC is not limited to 17.5 dB to 25 dB; smaller values ​​may also be included in the range.

[0069] <Receiving device and receiving method> Figure 10 shows the configuration of the receiving device 3800 in Embodiment 2 of the present invention. The receiving device 3800 in Figure 10 corresponds to the transmitting device 3600 in Figure 9 and reflects the functions of the transmitting device 3600. Components that are the same as those in existing ISDB-T receiving devices and the receiving device of Embodiment 1 are given the same reference numerals and their descriptions are omitted.

[0070] The receiving device 3800 has a configuration that adds a UL received TMCC signal reconstruction unit 3851, a delay unit 3853, a subtraction unit 3855, and a TMCC signal decoding unit 3835 compared to the receiving device 3500 in Embodiment 1 shown in Figure 7.

[0071] The operation of the receiving device 3800 is described below. The UL received TMCC signal reconstruction unit 3851 uses the transmission path estimate and the UL TMCC decoded signal output from the TMCC signal decoding unit 3535 to reconstruct the received TMCC signal (FFT output before equalization) as if it were transmitted using only UL.

[0072] The delay unit 3853 delays the pre-equalization FFT output from the demodulation unit 3311 to synchronize its timing with the output of the UL received TMCC signal reconstruction unit 3851. The subtraction unit 3855 subtracts the output of the UL received TMCC signal reconstruction unit 3851 from the output of the delay unit 3853 and outputs the received TMCC signal (pre-equalization FFT output) as if transmitted only via LL.

[0073] The TMCC signal decoding unit 3835 operates in essentially the same way as the TMCC signal decoding unit 3535, but it also has the function of outputting the TMCC signal for LL to the UL received signal reconstruction unit 3551 and the FEC decoding unit 3533.

[0074] Other operations are the same as those of the receiving device 3500 in Embodiment 1 shown in Figure 7. Note that the components of the receiving device 3800 in Figure 10, excluding the tuner unit 3305, may be included as an integrated circuit 3841.

[0075] With the above configuration, the receiving device compatible with the new broadcasting system can decode TMCC with LDM summation applied, and decode UL signals and LL signals.

[0076] (Embodiment 3) <Transmitting device and transmission method> Figure 11 shows the configuration of the transmitting device 4000 in Embodiment 3 of the present invention. Components that are the same as those in the conventional transmitting device and the transmitting device of Embodiment 1 are given the same reference numerals and their descriptions are omitted.

[0077] The transmitter 4000 in Figure 11 has a configuration that adds a pilot signal generation unit (for LL addition) 4081, a power difference control unit 3251, an addition unit 3261, and a power normalization unit 3271 compared to the transmitter 3000 in Embodiment 1 shown in Figure 1.

[0078] In Figure 11, the pilot signal generation unit (for LL addition) 4081 generates a pilot signal for synchronous regeneration using a pseudo-random binary sequence different from that of the pilot signal generation unit 5081. The power difference control unit 3251, the adder 3261, and the power normalization unit 3271 perform the same operations as in Figure 2 for the outputs of the pilot signal generation unit 5081 and the pilot signal generation unit (for LL addition) 4081.

[0079] The frame configuration unit 5101 constructs an ISDB-T transmission frame from the information data output from the frequency interleaving unit 5071, the synchronous regeneration pilot signal output from the power normalization unit 3271, and the TMCC signal output from the TMCC / AC signal generation unit 5091.

[0080] Other operations are the same as those of the transmitter 3000 in Embodiment 1 shown in Figure 1.

[0081] With the above configuration, LDM summing is also applied to pilot signals such as SP signals. As a result, existing ISDB-T receivers can observe the received C / N of information data and pilot signals at the same level, so the received C / N detection value using pilot signals becomes equivalent to the received C / N of information data, eliminating adverse effects. On the other hand, for receivers compatible with the new broadcasting system, the pilot signal with LDM summing applied is known, so transmission path estimation can be performed with high accuracy, and as a result, UL signals and LL signals can be decoded with high accuracy.

[0082] <Existing ISDB-T receiving equipment and receiving methods> The operation of the ISDB-T receiver 3300 in Figure 4 in response to the signal transmitted from the transmitter 4000 in Figure 11 is the same as the operation in response to the signal transmitted from the transmitter 3000 in Figure 1 in Embodiment 1.

[0083] In Figure 11, the signal transmitted from the transmitter 4000 undergoes LDM summation even with pilot signals such as SP signals. However, existing ISDB-T receivers can observe the received C / N of information data and pilot signals at the same level. Therefore, the received C / N detection value using the pilot signal becomes equivalent to the received C / N of information data, eliminating any adverse effects.

[0084] <Receiving device and receiving method> Figure 12 shows the configuration of the receiving device 4600 in Embodiment 3 of the present invention. The receiving device 4600 in Figure 12 corresponds to the transmitting device 4000 in Figure 11 and reflects the functions of the transmitting device 4000. Components that are the same as those in existing ISDB-T receiving devices and the receiving devices of Embodiments 1 and 10 are given the same reference numerals and their descriptions are omitted.

[0085] The receiving device 4600 has a configuration in which the demodulation unit 3311 is replaced with the demodulation unit 4611 compared to the receiving device 3500 in Figure 7 in Embodiment 1.

[0086] In the receiving device 4600 shown in Figure 12, the demodulation unit 4611 performs OFDM demodulation as a known SP signal, taking into account that the SP signals of the ISDB-T system and the new broadcasting system, which are generated using different pseudo-random binary sequences, are added together with a power difference.

[0087] Other operations are the same as those of the receiving device 3500 in Embodiment 1 shown in Figure 7. Note that the components of the receiving device 4600 in Figure 12, excluding the tuner unit 3305, may be included as an integrated circuit 4641.

[0088] With the above configuration, the receiving device compatible with the new broadcasting system can perform OFDM demodulation using the pilot signal, which has been summed using the LDM method, as a known signal, and accurately decode the UL signal and LL signal.

[0089] (Embodiment 4) <Transmitting device and transmission method> Figure 13 shows the configuration of the transmitter 4100 in Embodiment 4 of the present invention. Components that are the same as those in conventional transmitters and the transmitters of Embodiments 1 to 3 are given the same reference numerals and their descriptions are omitted.

[0090] The transmitting device 4100 in Figure 13 has a configuration in which the hierarchical processing unit 3041 is replaced with the hierarchical processing unit 4141 compared to the transmitting device 3000 in Embodiment 1 shown in Figure 1.

[0091] Figure 14 shows the configuration of the hierarchical processing unit 4141. Compared to the hierarchical processing unit 3041 in Embodiment 1 shown in Figure 2, this configuration includes the addition of a selector 4145.

[0092] When the selection signal "0" is input to the hierarchical processing unit 4141 in Figure 14, the selector 4145 selects the output of the power normalization unit 3271. In other words, the output of the hierarchical processing unit 4141 becomes the same as the output in Figure 2.

[0093] On the other hand, when the selection signal "1" is input to the hierarchical processing unit 4141 in Figure 14, the selector 4145 selects the output of the mapping unit 3241. In other words, the output of the hierarchical processing unit 4141 is the carrier modulation signal (LL) of the new broadcasting system, but the power cannot be reduced.

[0094] Figure 15 shows a part of the definition of the TMCC signal. Figures 15(a) and 15(b) show the definitions of B20 to B21 in the TMCC signal in the ISDB-T system and in this embodiment 4, respectively. As shown in Figure 15(b), in this embodiment 4, B20 to B21 = "10", which was undefined in the ISDB-T system, is newly defined as "second-generation terrestrial digital television broadcasting system". Therefore, when B20 to B21 = "00", a selection signal "0" is input to the hierarchical processing unit 4141, and when B20 to B21 = "01", a selection signal "1" is input to the hierarchical processing unit 4141.

[0095] Other operations are the same as those of the transmitter 3000 in Embodiment 1 shown in Figure 1.

[0096] With the above configuration, the hierarchical processing unit can select between the LDM method from the transmitter 3000 in Embodiment 1 shown in Figure 1 and the new broadcast (LL signal) only from the new broadcast method. This makes it possible to construct a system that takes into account the possibility that, several years after the application of the LDM method is put into practical use, the current broadcast (UL signal) using the ISDB-T method will be discontinued and only the new broadcast (LL signal) from the new broadcast method will remain.

[0097] <Existing ISDB-T receiving equipment and receiving methods> Regarding the operation of the ISDB-T receiver 3300 in Figure 4 in response to the signal transmitted from the transmitter 4300 in Figure 13, only the differences from the operation in response to the signal transmitted from the transmitter 3000 in Figure 1 in Embodiment 1 will be explained.

[0098] In the transmitting device 4300 shown in Figure 13, if B20~B21 = "10" in the TMCC signal, the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 shown in Figure 4 interprets the transmitted signal as undefined and determines that reception is impossible.

[0099] On the other hand, in the case where B20~B21=“00” in the TMCC signal of the transmitting device 4300 in Figure 13, the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 in Figure 4 interprets the transmitted signal as a terrestrial digital television broadcasting system (ISDB-T) and performs the same operation as in Embodiment 1, outputting TS for each layer of the ISDB-T system up to error correction decoding.

[0100] <Receiving device and receiving method> Figure 16 shows the configuration of the receiving device 4700 in Embodiment 4 of the present invention. The receiving device 4700 in Figure 16 corresponds to the transmitting device 4100 in Figure 13 and reflects the functions of the transmitting device 4100. Components that are the same as those in existing ISDB-T receiving devices and the receiving devices of Embodiments 1 to 3 are given the same reference numerals and their descriptions are omitted.

[0101] The receiving device 4700 has a configuration that, compared to the receiving device 3500 in Embodiment 1 shown in Figure 7, replaces the TMCC signal decoding unit 3535 with a TMCC signal decoding unit 4735 and adds a selector 4145.

[0102] The operation of the receiver 4700 in the case where B20~B21 = "10" in the TMCC signal of the transmitter 4300 in Figure 13 will be described below. In this case, the TMCC signal decoding unit 4735 interprets the transmission signal as a second-generation terrestrial digital television broadcasting system and outputs a selection signal "1" to the selector 4145.

[0103] Selector 4145 selects the output of the time deinterleaving unit 3321. Specifically, the output of selector 4145 is the mapping data of the I·Q coordinates after equalization of the carrier modulation signal (LL) of the new broadcasting system and the transmission path estimate, which corresponds to the signal transmitted by the transmitter 4100 in Figure 13 without power reduction.

[0104] The FEC decoding unit 3533 performs the same operation as in Figure 7 and outputs TS for each layer of the new broadcasting system, including error correction decoding.

[0105] Other operations are the same as those of the receiving device 3500 in Embodiment 1 shown in Figure 7. Note that the components of the receiving device 4700 in Figure 16, excluding the tuner unit 3305, may be included as an integrated circuit 4741.

[0106] On the other hand, in the transmitting device 4300 in Figure 13, if B20~B21=“00” in the TMCC signal, the TMCC signal decoding unit 4735 interprets the transmitted signal as a terrestrial digital television broadcasting system and outputs a selection signal “0” to the selector 4145. Other operations are the same as those of the receiving device 3500 in Embodiment 1 shown in Figure 7, and it outputs TS (UL decoded signals) for each layer of the ISDB-T system and TS (LL decoded signals) for each layer of the new broadcasting system.

[0107] With the above configuration, the receiving device compatible with the new broadcasting system can output TS (LL decoded signals) for each layer of the new broadcasting system even if the current ISDB-T broadcasting (UL signal) is discontinued several years after the LDM method is put into practical use, and only the new broadcasting (LL signal) remains under the new broadcasting system. In particular, in this case, since the signal transmitted by the transmitting device 4100 in Figure 13 is received without reducing power, the area in which the new broadcasting system can be viewed by the receiving device 4700 will be expanded.

[0108] (Embodiment 5) <Transmitting device and transmission method> Figure 17 shows the configuration of the transmitter 4200 in Embodiment 5 of the present invention. Components that are the same as those in conventional transmitters and the transmitters of Embodiments 1 to 4 are given the same reference numerals and their descriptions are omitted.

[0109] The transmitter 4200 in Figure 17 is configured in a way that, compared to the transmitter 4100 in Embodiment 4 shown in Figure 13, the hierarchical synthesis unit 5051, time interleaving unit 5061, frequency interleaving unit 5071, pilot signal generation unit 5081, TMCC / AC signal generation unit 5091, frame configuration unit 5101, and OFDM signal generation unit 5111 are replaced with the hierarchical synthesis unit 4251, time interleaving unit 4261, frequency interleaving unit 4271, pilot signal generation unit 4281, TMCC / AC signal generation unit 4291, frame configuration unit 4301, and OFDM signal generation unit 4311, respectively. A selection signal is input to these processing units, and the processing is switched based on whether the value is "0" or "1".

[0110] When the selection signal is "0", these processing units operate in the same way as the transmitter 4100 in Embodiment 4 shown in Figure 3, with FFT size and GI values ​​corresponding to the same values ​​as the ISDB-T method (FFT size has three types: 2k, 4k, and 8k, and GI has four types: 1 / 4, 1 / 8, 1 / 16, and 1 / 32).

[0111] On the other hand, the operation of the transmitter 4200 when the selection signal is "1" is described below. In this case, only the new broadcast (LL signal) under the new broadcasting system will be used, and these processing units will operate in accordance with values ​​different from those of the ISDB-T system (for example, there are five types of FFT sizes: 2k, 4k, 8k, 16k, and 32k, and six types of GI: 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, and 1 / 128).

[0112] When the selection signal is "1", the hierarchical synthesis unit 4251, the time interleaving unit 4261, and the frequency interleaving unit 4271 also have processing functions for two types of FFT sizes: 16k and 32k.

[0113] Figure 18 shows the segment configuration of this embodiment 5, using a synchronous modulation section with an FFT size of 32k as an example, where the selection signal is "1". As shown in Figure 26, the segment of the synchronous modulation section with an FFT size of 2k consists of 108 carriers. On the other hand, as shown in Figure 18, when the FFT size is 32k, it consists of 1728 carriers, which is 16 times the FFT size. In Figure 18, the SP signal is arranged repeatedly with a period of 4 symbols, similar to Figure 26, and shifted by 3 carriers for each symbol. However, the arrangement pattern of the SP signal is not limited to this, and a configuration in which multiple types can be selected is also possible. In addition, the carriers of the TMCC signal and AC signal are arranged randomly in the frequency direction to reduce the effect of periodic dips in the transmission line characteristics due to multipath. The number of carriers per segment of the TMCC signal and AC signal is 16 times that when the FFT size is 2k, but the value is not limited to this. In this way, the pilot signal generation unit 4281 and the TMCC / AC signal generation unit 4291 generate a pilot signal for synchronous regeneration, such as the SP signal, and the TMCC / AC signal, respectively.

[0114] The frame constructor 4301 constructs a transmission frame from the information data output from the frequency interleaving unit 4271, the pilot signal for synchronous regeneration output from the pilot signal generation unit 4281, and the TMCC signal output from the TMCC / AC signal generation unit 4291. When the selection signal is "1", the frame constructor 4301 also has processing capabilities for two types of FFT sizes: 16k and 32k.

[0115] The OFDM signal generation unit 4311 inserts IFFT and GI (Guard Interval) into the transmission frame configuration output from the frame configuration unit 4301 and outputs a digital baseband transmission signal. When the selection signal is "1", the OFDM signal generation unit 4311 also has processing functions for two types of FFT sizes, 16k and 32k, and two types of GI, 1 / 64 and 1 / 128.

[0116] Other operations are the same as those of the transmitter 4100 in Embodiment 4 shown in Figure 13.

[0117] With the above configuration, when the transmitter 3000 in Embodiment 1 shown in Figure 1 can select between the LDM method and the new broadcast (LL signal) only signal from the new broadcast method, it is possible to construct a system that takes into account the possibility that, several years after the application of the LDM method is put into practical use, the current broadcast (UL signal) using the ISDB-T method will be discontinued and only the new broadcast (LL signal) using the new broadcast method will be used. In particular, when only the new broadcast (LL signal) using the new broadcast method is used, it will be possible to operate with FFT size and GI values ​​that correspond to different values ​​than those of the ISDB-T method.

[0118] <Existing ISDB-T receiving equipment and receiving methods> Regarding the operation of the ISDB-T receiver 3300 in Figure 4 in response to the signal transmitted from the transmitter 4200 in Figure 17, only the differences from the operation in response to the signal transmitted from the transmitter 4100 in Figure 13 in Embodiment 4 will be explained.

[0119] In the transmitter 4200 shown in Figure 17, when B20~B21 = "10" in the TMCC signal, the ISDB-T receiver 3300 cannot detect the signal transmitted with an FFT size different from that of the ISDB-T method (16k, 32k). The ISDB-T receiver 3300 can decode the TMCC signal for a signal transmitted with an FFT size the same as that of the ISDB-T method (2k, 4k, 8k), and determines that reception is impossible, as in Embodiment 4. In both cases, reception is determined to be impossible, but the former is determined by the inability to detect the signal, while the latter is determined by the TMCC signal decoding result.

[0120] On the other hand, in the case where B20~B21=“00” in the TMCC signal of the transmitting device 4300 in Figure 13, the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 in Figure 4 interprets the transmitted signal as a terrestrial digital television broadcasting system (ISDB-T) and performs the same operation as in Embodiment 1, outputting TS for each layer of the ISDB-T system up to error correction decoding.

[0121] <Receiving device and receiving method> Figure 19 shows the configuration of the receiving device 4800 in Embodiment 5 of the present invention. The receiving device 4800 in Figure 19 corresponds to the transmitting device 4200 in Figure 17 and reflects the functions of the transmitting device 4200. Components that are the same as those in existing ISDB-T receiving devices and the receiving devices of Embodiments 1 to 4 are given the same reference numerals and their descriptions are omitted.

[0122] The receiver 4800 has a configuration in which the demodulation unit 3311, frequency deinterleaving unit 3315, time deinterleaving unit 3321, and TMCC signal decoding unit 4735 are replaced with the demodulation unit 4811, frequency deinterleaving unit 4815, time deinterleaving unit 4821, and TMCC signal decoding unit 4835, respectively, compared to the receiver 4700 in Embodiment 4 shown in Figure 16. A selection signal is generated in the TMCC signal decoding unit 4835 and input to these processing units, and the processing is switched based on whether the value is "0" or "1".

[0123] When the selection signal is "0", these processing units operate in the same way as the receiving device 4700 in Embodiment 4 shown in Figure 16, with FFT size and GI values ​​corresponding to the same values ​​as the ISDB-T system (FFT size has three types: 2k, 4k, and 8k; GI has four types: 1 / 4, 1 / 8, 1 / 16, and 1 / 32). Therefore, the receiving device 4800 outputs the TS (UL decoded signal) for each layer of the ISDB-T system and the TS (LL decoded signal) for each layer of the new broadcasting system.

[0124] On the other hand, when the selection signal is "1", and only the new broadcast (LL signal) using the new broadcasting system is available, these processing units will also operate in response to values ​​different from those of the ISDB-T system (for example, five types of FFT size: 2k, 4k, 8k, 16k, and 32k; and six types of GI: 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, and 1 / 128).

[0125] When the selection signal is "1", the demodulator 4811 performs OFDM demodulation, but it also has processing capabilities for two types of FFT sizes, 16k and 32k, and two types of GI, 1 / 64 and 1 / 128.

[0126] The TMCC signal decoding unit 4835 decodes the TMCC signal from the pre-equalization FFT output output from the demodulation unit 4811, and also has processing capabilities for two types of FFT sizes: 16k and 32k. Based on the decoding result of the TMCC signal, the TMCC signal decoding unit 4835 generates and outputs a selection signal.

[0127] When the selection signal is "1", the frequency deinterleaving section 4815 and the time deinterleaving section 4821 also have processing capabilities for two types of FFT sizes: 16k and 32k.

[0128] Other operations are the same as those of the receiving device 4700 in Embodiment 4 shown in Figure 16, and it outputs TS for each layer of the new broadcasting system, including error correction decoding. Note that the components of the receiving device 4800 in Figure 17, excluding the tuner unit 3305, may be included as an integrated circuit 4841.

[0129] With the above configuration, the receiving device compatible with the new broadcasting system will output the TS (LL decoded signals) for each layer of the new broadcasting system even if the current ISDB-T broadcasting (UL signal) is discontinued several years after the LDM method is put into practical use, and only the new broadcasting (LL signal) remains. In particular, in this case, since the signal transmitted by the transmitting device 4200 in Figure 17 is received without reducing power, the area in which the new broadcasting system can be viewed by the receiving device 4800 will expand, and the receiving device 4800 will be able to operate with FFT size and GI values ​​that are different from those of the ISDB-T system.

[0130] (Embodiment 6) <Transmitting device and transmission method> Figure 20 shows the configuration of the transmitting device 4400 in Embodiment 6 of the present invention. Components that are the same as those in conventional transmitting devices and the transmitting devices of Embodiments 1 to 5 are given the same reference numerals and their descriptions are omitted.

[0131] The transmitter 4400 in Figure 20 is configured to be different from the transmitter 4100 in Embodiment 4 shown in Figure 13, by adding a time interleaving unit 4461, a frequency interleaving unit 4471, a pilot signal generation unit 4481, a frame configuration unit 4501, a signaling generation unit 4541, a preamble generation unit 4551, and two selectors 4445-1 to 4445-2, and replacing the OFDM signal generation unit 5111 with an OFDM signal generation unit 4311. Based on whether the value of the selection signal is "0" or "1", the output of the transmitter 4400 is selected to be either the LDM method signal from the transmitter 3000 in Embodiment 1 shown in Figure 1, or the signal for new broadcasting only using the new broadcasting method.

[0132] When the selection signal is "0", the LDM transmission signal from the transmitter 3000 in Embodiment 1 shown in Figure 1 is selected and output from the transmitter 4400. In this case, similar to the transmitter 4100 in Embodiment 4 shown in Figure 13, the FFT size and GI values ​​operate in accordance with the same values ​​as the ISDB-T method (FFT size has three types: 2k, 4k, and 8k, and GI has four types: 1 / 4, 1 / 8, 1 / 16, and 1 / 32).

[0133] On the other hand, the operation of the transmitter 4400 when the selection signal is "1" is explained below. In this case, it operates in accordance with values ​​different from those of the ISDB-T system (for example, five types of FFT size: 2k, 4k, 8k, 16k, and 32k, and six types of GI: 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, and 1 / 128). Furthermore, instead of dividing the multiple layers in the frequency direction using a segment structure, it is divided in the time direction using a structure that stores each layer in a subframe.

[0134] When the selection signal is "1", the time interleaving section 4461 and the frequency interleaving section 4471 perform interleaving using a subframe structure instead of interleaving using a segment structure. It also has processing capabilities for two FFT sizes: 16k and 32k.

[0135] Figure 21 shows the SP signal arrangement pattern of this embodiment 6 when the selection signal is "1". As shown in Figure 21, the SP signal is arranged repeatedly with a period of 4 symbols, similar to Figures 18 and 78, and shifted by 3 carriers for each symbol. However, the SP signal arrangement pattern is not limited to this, and a configuration that allows selection from multiple types is also possible. Also, the TMCC signal and AC signal carriers are not provided. In this way, the pilot signal generation unit 4481 generates a pilot signal for synchronous regeneration, such as the SP signal.

[0136] The frame configuration unit 4501 constructs a transmission frame from the information data output from the frequency interleaving unit 4471 and the pilot signal for synchronous regeneration output from the pilot signal generation unit 4481. In each transmission frame, the frame configuration unit 4501 stores the information data for each layer in subframes.

[0137] When the selection signal is "1", the selector 4445-1 selects and outputs the output of the frame component 4501.

[0138] The OFDM signal generation unit 4311 inserts IFFT and GI into the transmission frame configuration output from selector 4445-1 and outputs a digital baseband transmission signal. When the selection signal is "1", the OFDM signal generation unit 4311 also has processing capabilities for two types of FFT sizes, 16k and 32k, and two types of GI, 1 / 64 and 1 / 128.

[0139] The signaling generation unit 4541 generates signaling (control information similar to TMCC), which is control information. The preamble generation unit 4551 generates a preamble for transmitting the signaling and adds it to the beginning of the transmission frame.

[0140] When the selection signal is "1", the selector 4445-2 selects and outputs the output of the preamble generation unit 4551.

[0141] Other operations are the same as those of the transmitter 4100 in Embodiment 4 shown in Figure 13.

[0142] With the above configuration, when it is possible to select between the LDM method and the new broadcast (LL signal) only signal from the new broadcast method from the transmitter 3000 in Embodiment 1 shown in Figure 1, it is possible to construct a system that takes into account the possibility that the current broadcast (UL signal) using the ISDB-T method will be discontinued several years after the application method of the LDM method is put into practical use, and only the new broadcast (LL signal) using the new broadcast method will be used. In particular, when only the new broadcast (LL signal) using the new broadcast method is used, it will be possible to operate with FFT size and GI values ​​corresponding to different values ​​from the ISDB-T method, and it will also be possible to divide in the time direction using a structure that stores each layer in a subframe.

[0143] <Existing ISDB-T receiving equipment and receiving methods> Regarding the operation of the ISDB-T receiver 3300 in Figure 4 in response to the signal transmitted from the transmitter 4400 in Figure 20, only the differences from the operation in response to the signal transmitted from the transmitter 4100 in Figure 13 in Embodiment 4 will be explained.

[0144] In the transmitter 4400 shown in Figure 20, if the selection signal is "1", the ISDB-T receiver 3300 cannot detect the signal transmitted using a time-division frame structure with a preamble and subframe.

[0145] On the other hand, when the selection signal is "0" in the transmitting device 4400 in Figure 20, the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 in Figure 4 interprets the transmitted signal as a terrestrial digital television broadcasting system (ISDB-T) and performs the same operation as in Embodiment 1, outputting TS for each layer of the ISDB-T system, including error correction decoding.

[0146] <Receiving device and receiving method> Figure 22 shows the configuration of the receiving device 4900 in Embodiment 6 of the present invention. The receiving device 4900 in Figure 22 corresponds to the transmitting device 4400 in Figure 20 and reflects the functions of the transmitting device 4400. Components that are the same as those in existing ISDB-T receiving devices and the receiving devices of Embodiments 1 to 5 are given the same reference numerals and their descriptions are omitted.

[0147] Compared to the receiver 3500 in Embodiment 1 shown in Figure 7, the receiver 4900 has the addition of a frequency deinterleaving unit 4915, a time deinterleaving unit 4921, a preamble detection unit 4961, and a selector 4945, and the demodulation unit 3311 has been replaced with a demodulation unit 4811.

[0148] In the transmitter 4400 shown in Figure 20, when the selection signal is "0", the receiver 4900 shown in Figure 22 operates in the same manner as the receiver 3500 in Embodiment 1 shown in Figure 7, outputting the TS (UL decoded signal) for each layer of the ISDB-T system and the TS (LL decoded signal) for each layer of the new broadcasting system. The receiver 4900 operates in accordance with the same FFT size and GI values ​​as the ISDB-T system (FFT size has three types: 2k, 4k, and 8k; GI has four types: 1 / 4, 1 / 8, 1 / 16, and 1 / 32).

[0149] On the other hand, regarding the case where the selection signal is "1" in the transmitting device 4400 of Figure 20, the operation of the receiving device 4900 will be explained below.

[0150] The preamble detection unit 4961 detects the preamble from the digital received signal of the A / D conversion unit 3308 and outputs the signaling of the new broadcasting system contained in the preamble.

[0151] The demodulation unit 4811 performs OFDM demodulation, but also has processing capabilities for two types of FFT sizes, 16k and 32k, and two types of GI, 1 / 64 and 1 / 128.

[0152] The frequency deinterleaving section 4915 and the time deinterleaving section 4921 perform deinterleaving using a subframe structure on the output of the demodulation section 4811.

[0153] Selector 4945 selects and outputs the output of the time deinterleaving unit 4921.

[0154] Other operations are the same as those of the receiving device 3500 in Embodiment 1 shown in Figure 7, and output TS for each layer of the new broadcasting system, including error correction decoding. Note that the components of the receiving device 4900 in Figure 22, excluding the tuner unit 3305, may be included as an integrated circuit 4941.

[0155] With the above configuration, the receiving device compatible with the new broadcasting system will output the TS (LL decoded signals) of each layer of the new broadcasting system even if the current ISDB-T broadcasting (UL signal) is discontinued several years after the LDM method is put into practical use, and only the new broadcasting (LL signal) remains under the new broadcasting system. In particular, in this case, since the signal transmitted by the transmitter 4400 in Figure 20 is received without reducing power, the area in which the new broadcasting system can be viewed by the receiving device 4900 will expand, and the receiving device 4900 will be able to operate with FFT size and GI values ​​that are different from those of the ISDB-T system. Furthermore, in this case, the receiving device 4900 will be able to operate with transmitted signals that are divided in the time direction by using a structure that stores each layer in a subframe.

[0156] (supplement) This disclosure is not limited to what is described in Embodiments 1 to 6 above, and can be implemented in any form to achieve the purposes of this disclosure and any related or incidental purposes, for example, the following:

[0157] (1) In embodiments 1 to 6, the input to the transmission device for the new broadcasting system was set to TS, but it is not limited to this, and may also be IP packets, MMT (MPEG Media Transport), or packets encapsulated therein.

[0158] (2) In embodiments 1 to 5, the definitions of B110 to B121 in the TMCC signal are as shown in Figure 3, but are not limited to this. The UL / LL signal power ratio, the carrier modulation mapping scheme for each layer LL signal, and the LDPC coding rate of each layer LL signal may differ from those in Figure 3.

[0159] (3) In embodiments 4 to 6, the FFT size was set to 2k, 4k, 8k, 16k, and 32k (5 types) and the GI was set to 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, and 1 / 128 (6 types), which are different values ​​from the ISDB-T method. However, this is just an example and is not limited to these.

[0160] (4) In embodiments 1 to 6, the LDM method addition is performed immediately after the mapping unit, but the configuration is not limited to this. The LDM method addition can be performed between the mapping unit and the OFDM signal generation unit.

[0161] (5) Some of the embodiments 1 to 6 may be combined with each other.

[0162] (6) Embodiments 1 to 6 described above may relate to implementations using hardware and software. The embodiments described above may be implemented or executed using a computing device (processor). The computing device or processor may be, for example, a main processor / general-purpose processor, a digital signal processor (DSP), an ASIC (application-specific integrated circuit), an FPGA (field-programmable gate array), or other programmable logic devices. The embodiments described above may be executed or realized by combining these devices.

[0163] (7) Embodiments 1 to 6 may be implemented by a mechanism of software modules that are executed by a processor or directly by hardware. A combination of software modules and hardware implementations is also possible. The software modules may be stored in various types of computer-readable storage media, such as RAM, EPROM, EEPROM, flash memory, registers, hard disks, CD-ROMs, DVDs, etc. [Industrial applicability]

[0164] The transmitting device, transmitting method, receiving device, receiving method, integrated circuit, and program relating to this disclosure can be applied to wireless transmission systems. [Explanation of Symbols]

[0165] 3000, 3600, 4000, 4100, 4200, 4400, 5000 Transmitter 3500, 3800, 4600, 4700, 4800, 4900 receiving device 3341, 3541, 3841, 4641, 4741, 4841, 4941 Integrated Circuits 3300 ISDB-T receiver 5011 TS remultiplexer 5021 RS encoder 5031 Hierarchy division part 3041, 4141, 5041 Hierarchical Processing Unit 4251, 5051 Hierarchical Combination Unit 4261, 4461, 5061 Time Interleaved Sections 3321, 4821, 4921 hour deinterleave section 4271, 4471, 5071 frequency interleaving section 3315, 4815, 4915 frequency deinterleaving section 3081, 4281, 4481, 5081 Pilot signal generation unit 4081 Pilot signal generation unit (for LL addition) 4291, 5091 TMCC / AC signal generation section 3691 TMCC / AC signal generator (for LL) 4301, 4501, 5101 Frame components 4311, 5111 OFDM signal generation section 5121 D / A Conversion Unit 5131 Frequency conversion section 3201, 5201 Energy diffusion section 3461, 3569 Energy backdiffusion section 5211 Byte Interleaving Section 3451 Byte Deinterleaving Section 5221 Convolutional encoder 3231, 5231 bit interleaved section 3411, 3563, 3911 Bit Deinterleaving Section 3241, 5241 Mapping section 3401, 3561 Demapping section 3211 BCH encoder 3567 BCH Decoding Unit 3221 LDPC encoder 3565 LDPC decoding section 3251 Power Difference Control Unit 3261 Addition section 3271 Power normalization section 3305 Tuner section 3308 A / D conversion unit 4611, 4811 Demodulation Unit 3331 Multi-layer TS playback unit 3333, 3533 FEC-based conversion section 3335, 3535, 3835, 4735, 4835 TMCC signal decoding unit 3421 Depancture Department 3431, 3571 TS playback section 3441 Viterbi decoding unit 3551 UL Received Signal Reconstruction Unit 3851 UL Received TMCC Signal Reconstruction Unit 3555, 3855 Subtraction section 3553, 3853 Delay section 4145, 4445, 4945 4551 Preamble generation unit 4961 Preamble detection unit 5301 Segment division section 5311 Inter-segment interleaving section 5321 Segment-internal carrier rotation section 5331 Segment-specific carrier randomization section

Claims

1. A transmitting device that multiplexes and transmits a plurality of data sequences, including a first data sequence of a first layer and a second data sequence of a second layer, by superimposed coding, A first bit interleaving unit generates a first bit sequence of the first data sequence by performing bit interleaving on the first data sequence, A second bit interleaving unit generates a second bit sequence of the second data sequence by performing bit interleaving on the second data sequence, A first mapping unit generates a first modulation symbol sequence of the first data sequence by mapping the first bit sequence of the first data sequence, A second mapping unit generates a second modulation symbol sequence of the second data sequence by mapping the second bit sequence of the second data sequence, A superposition unit that generates a multiplexed signal by superimposing the first modulation symbol sequence and the second modulation symbol sequence at a predetermined amplitude ratio, A control signal generation unit that generates control signals from control information indicating the aforementioned multiplexing method, The system includes a transmitting unit that transmits the multiplexed signals and the control signals, The aforementioned control signal is transmitted by the transmitting unit without being superimposed on other signals. The control information includes information indicating that the second data sequence is multiplexed in the multiplexed signal, The aforementioned information is indicated by a flag set at a bit position in a predetermined bit array that is not used in the first communication standard and is used in a second communication standard that is different from the first communication standard. Transmitter.

2. A receiving device for receiving a transmission signal which includes a multiplexed signal obtained by superimposing coding a first modulation symbol sequence generated from a first data sequence of a first hierarchy and a second modulation symbol sequence generated from a second data sequence of a second hierarchy, and a control signal generated from control information indicating the multiplexing method, A receiving unit that receives the aforementioned transmission signal and acquires a received signal, A control information acquisition unit demodulates the received signal corresponding to the control signal and acquires the control information, A first demodulation unit that demodulates the received signal corresponding to the multiplexed signal based on the control information to obtain a first data sequence, A mapping unit generates a bit sequence from the output of the first demodulation unit, A bit interleaving unit that generates the first modulation symbol sequence by performing bit interleaving on the bit sequence, A delay unit that delays the received signal corresponding to the multiplexed signal for a predetermined time, A subtraction unit that subtracts the components of the first modulation symbol sequence from the received signal corresponding to the multiplexed signal that has been delayed by the delay unit, The system includes a second demodulation unit that demodulates the received signal corresponding to the multiplexed signal, in which the components of the first modulation symbol sequence have been subtracted based on the control information, to obtain a second data sequence, The control signal included in the aforementioned transmission signal is not superimposed with other signals. The control information includes information indicating that the second data sequence is multiplexed in the multiplexed signal, The aforementioned information is indicated by a flag set at a bit position in a predetermined bit array that is not used in the first communication standard and is used in a second communication standard that is different from the first communication standard. Receiving device.

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