Transmitting device and receiving device

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 has been 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 employs 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 object, a transmission device according to an aspect of the present disclosure is a transmission 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, wherein a first bit interleaving unit that generates a first bit string of the first data sequence by performing bit interleaving on the first data sequence, a second bit interleaving unit that generates a second bit string of the second data sequence by performing bit interleaving on the second data sequence, a first mapping unit that generates a first modulated symbol string of the first data sequence by mapping the first bit string of the first data sequence, a second mapping unit that generates a second modulated symbol string of the second data sequence by mapping the second bit string of the second data sequence, a superimposing unit that generates a multiplexed signal by superimposing the first modulated symbol string and the second modulated symbol string at a predetermined amplitude ratio, a control signal generation unit that generates a control signal from control information indicating the multiplexing method, 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 that is not used in a first communication standard and is used in a second communication standard different from the first communication standard among a predetermined bit array.

Advantages of the Invention

[0006] According to the above transmission device, in wireless transmission, when implemented in combination with an existing service, the transmission capacity can be increased compared to the existing service without using another frequency band.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

Figure 22

Figure 23

Figure 24

Figure 25

Figure 26

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 transmission device 5000 will be described below. A plurality of TSs output from an MPEG-2 multiplexing unit (not shown) are input to the TS remultiplexing unit 5011 to have a TS packet arrangement suitable for signal processing in data segment units. The TS remultiplexing unit 5011 converts them into a burst signal format in units of 188 bytes and a single TS by a clock that is 4 times the FFT (Fast Fourier Transform) sample clock. The RS encoding unit 5021 performs RS encoding and adds 16-byte parity to the information of 188 bytes. When performing hierarchical transmission, the hierarchical division unit 5031 performs hierarchical division of up to three systems (A layer, B layer, C layer) in accordance with the specification of hierarchical information.

[0010] FIG. 24 is a diagram showing the configuration of the hierarchical processing unit 5041. The hierarchical processing unit 5041 includes an energy dispersal unit 5201, a byte interleaving unit 5211, a convolutional encoding unit 5221, a bit interleaving unit 5231, and a mapping unit 5241. The hierarchical processing unit 5041 mainly performs digital data processing such as error correction encoding and interleaving, and carrier modulation on the input hierarchical data. The error correction, interleaving length, and carrier modulation method are set independently for each layer.

[0011] In FIG. 23, the hierarchical composition unit 5051 performs hierarchical composition of data of up to three systems (A layer, B layer, C layer) output from the hierarchical processing units 5041-A to C.

[0012] FIG. 25 is a diagram showing the configuration of the frequency interleaving section 5071. The frequency interleaving section 5071 includes a segment division section 5301, an inter-segment interleaving section 5311-D and S, an intra-segment carrier rotation section 5321-P and D and S, and an intra-segment carrier randomization section 5331-P and D and S. In order to effectively exert the error correction coding ability against electric field fluctuations and multipath interference in mobile reception, the time interleaving section 5061 performs intra-segment convolutional interleaving on the output from the hierarchical synthesis section 5051, and the frequency interleaving section 5071 performs interleaving between segments and within segments. In the frequency interleaving section 5071, the segment division section 5301 assigns data segment numbers 0 to 12 in the order of the partial reception section, the differential modulation section (the segment in which the carrier modulation is specified as DQPSK), and the synchronous modulation section (the segment in which the carrier modulation is specified as QPSK, 16QAM, or 64QAM). Regarding the relationship between the hierarchical configuration and the data segments, the data segments of each hierarchy are arranged continuously in ascending order of numbers, and the hierarchies are A hierarchy, B hierarchy, and C hierarchy starting from the hierarchy including the data segment with the smallest number. Even when the hierarchies are different, inter-segment interleaving is performed on the data segments belonging to the same type of modulation section.

[0013] In FIG. 23, the pilot signal generation section 5081 generates a pilot signal for synchronous reproduction. In order to assist the demodulation and decoding of the receiving apparatus for hierarchical transmission in which a plurality of transmission parameters are mixed, the TMCC / AC signal generation section 5091 generates a TMCC signal which is control information and an AC signal which is additional information. The frame configuration section 5101 configures an ISDB-T system transmission frame from the information data output from the frequency interleaving section 5071, the pilot signal for synchronous reproduction output from the pilot signal generation section 5081, and the TMCC signal output from the TMCC / AC signal generation section 5091.

[0014] Fig. 26 shows the segment configuration of the ISDB-T system, taking the synchronization modulation section (QPSK, 16QAM, 64QAM) in Mode 1 (FFT size is 2k) as an example. Instead of transmitting the scattered pilot signal (hereinafter referred to as the SP signal: Scattered Pilot signal) as a pilot signal for synchronous playback for each subcarrier, in the frequency (subcarrier) direction and the time (symbol) direction, for the symbol with symbol number n, the carrier position where the carrier number k satisfies k = 3(n mod 4)+12p (mod represents the remainder operation, and p is an integer) is used for transmission. That is, as shown in Fig. 26, the SP signals are repeatedly arranged in a cycle of 4 symbols, and are arranged with a shift of 3 carriers for each symbol. The SP signals arranged in this way are modulated into binary values in a specific pattern determined by their carrier positions and then transmitted. Also, the carriers of the TMCC signal and the AC signal are randomly arranged in the frequency direction in order to reduce the influence of the periodic dips in the transmission path characteristics due to multipath. In the ISDB-T system, the information transmission signal is modulated using modulation methods such as QPSK, 16QAM, and 64QAM by using the carriers where the SP signal, the TMCC signal, and the AC signal are not arranged, and then transmitted.

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

[0016] By the way, in recent years, there has been an active discussion on Ultra HDTV (UHDTV) services that exceed the resolution of HDTV services. In order to realize UHDTV services with a high bit rate, it is important to study a transmission method that enables high-capacity transmission with higher frequency utilization efficiency than the ISDB-T method. As a method of performing high-capacity transmission without using other frequency bands while continuing the current broadcast service using the ISDB-T method, a method of applying the LDM (Layered Division Multiplexing) method to the current ISDB-T broadcast service to increase the transmission capacity has been studied (Non-Patent Document 2).

[0017] In Non-Patent Document 2, a large signal level is assigned to the transmission RF signal of the current broadcast by the ISDB-T method, and a small signal level is assigned to the transmission RF signal by the new broadcast method (the same RF frequency as the ISDB-T method). The former is called UL (Upper Level), and the latter is called LL (Lower Level). The transmission RF signals of UL and LL are added and output from the transmission antenna.

[0018] A receiving device compatible with the new broadcast method first decodes the UL data from the received RF signal, and also reconstructs the RF received signal when transmitted only by UL using the transmission path estimation value at that time. Then, by subtracting the reconstructed UL RF received signal from the received RF signal, the RF received signal when transmitted only by LL is extracted and the LL data is decoded.

[0019] When receiving only the UL signal, since the LL signal can be regarded as noise, no special processing such as the above reconstruction and subtraction is necessary. Therefore, this also applies to existing receiving devices compatible with the current broadcast by the ISDB-T method.

[0020] In Non-Patent Document 2, the possibility of continuing the current broadcast by the ISDB-T method and performing high-capacity transmission without using other frequency bands is studied by such an application method of the LDM method.

[0021] However, in such an application method of the LDM system, a method must be constructed such that a receiver compatible with the new broadcast system can accurately decode the UL signal and the LL signal, and the method must eliminate the adverse effects on existing receivers compatible with the current broadcast. In addition, it is necessary to construct a method that anticipates that the current broadcast (UL signal) by the ISDB-T system will be stopped several years after such an application method of the LDM system is put into practical use, and only the new broadcast (LL signal) by the new broadcast system will remain.

[0022] The inventions according to Embodiments 1 to 6 described below are made to solve the above problems, and an object thereof is to provide a transmission device, a transmission method, a reception device, a reception method, an integrated circuit, and a program that newly use the LDM system for the current broadcast.

[0023] Hereinafter, each embodiment will be described in detail with reference to the drawings.

[0024] (Embodiment 1) <Transmission Device and Transmission Method> FIG. 1 is a diagram showing the configuration of a transmission device 3000 according to Embodiment 1 of the present invention. The same components as those of the conventional transmission device are denoted by the same reference numerals, and the description thereof is omitted.

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

[0026] Hereinafter, the operation of the transmission device 3000 will be described. A plurality of TSs for the new broadcast system output from an MPEG-2 multiplexing unit (not shown) are input to the hierarchical processing units 3041-A to C as LL signals, respectively. On the other hand, a plurality of TSs for the ISDB-T system are input to the TS remultiplexing unit 5011 as UL signals, and the TS remultiplexing unit 5011, the RS encoding unit 5021, and the hierarchical division unit 5031 perform the same processing as the conventional transmission device 5000 shown in FIG. 23.

[0027] FIG. 2 is a diagram showing the configuration of the hierarchical processing unit 3041. Compared with the conventional hierarchical processing unit 5041 shown in FIG. 24, it is a configuration in which an energy diffusion unit 3201, a BCH encoding unit 3211, an LDPC encoding unit 3221, a bit interleaving unit 3231, a mapping unit 3241, a power difference control unit 3251, an addition unit 3261, and a power normalization unit 3271 are added.

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

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

[0030] The power difference control unit 3251 reduces the power of the carrier modulation signal (LL) output from the mapping unit 3241 below the power of the carrier modulation signal (UL) output from the mapping unit 5241 based on the LL signal power instruction signal.

[0031] The addition 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 indication signal, the power normalization unit 3271 normalizes the power of the output signal of the addition unit 3261 so that it becomes the same power as the power of the carrier modulation signal (UL) output from the mapping unit 5241.

[0033] In the transmission device 3000 of FIG. 1, after the hierarchical synthesis unit 5051, the same operations as those of the conventional transmission device 5000 shown in FIG. 23 are performed. However, as will be described later using FIG. 3 (a part of the definition of the TMCC signal), in order to apply the LDM method performed by the hierarchical processing unit 3041 in FIG. 2, a partial change is made from the definition of the TMCC signal of the ISDB-T method.

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

[0035] · B110: "0" indicates the presence of LDM transmission, "1" indicates the absence of LDM transmission (only for the ISDB-T method). Thus, without adversely affecting existing ISDB-T receiving devices, receiving devices compatible with the new broadcast method can recognize the presence or absence of LDM transmission.

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

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

[0038] With the above configuration, after the hierarchical synthesis unit 5051, the same operations as in the ISDB-T system are performed, and by allocating control information related to LDM transmission to the bit groups that were undefined in the TMCC signal of the ISDB-T system, it is possible to eliminate the adverse effects on existing receiving devices compatible with current broadcasts.

[0039] Also, in Non-Patent Document 2, since the transmission RF signals of UL and LL are simply added, the added transmission signal has poor accuracy as an LDM system. On the other hand, in the first embodiment, since the addition of the LDM system is not performed particularly for the SP signal, the transmission signal has good accuracy as an LDM system. Therefore, accurate channel estimation can be performed for both existing receiving devices compatible with current broadcasts and receiving devices compatible with the new broadcast system. As a result, particularly for receiving devices compatible with the new broadcast system, accurate decoding of UL signals and LL signals can be performed.

[0040] <Existing ISDB-T Receiving Device and Receiving Method> FIG. 4 is a diagram showing the configuration of an existing ISDB-T receiving device 3300. The ISDB-T receiving device 3300 in FIG. 4 corresponds to the transmitting device 5000 in FIG. 23 and reflects the functions of the transmitting device 5000.

[0041] The ISDB-T receiving device 3300 includes 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 reproduction unit 3331, an FEC decoding unit 3333, and a TMCC signal decoding unit 3335.

[0042] The operation of the ISDB-T receiving apparatus 3300 will be described below. When an analog RF transmission signal is input from the receiving antenna Rx-1 to the signal transmitted from the transmission apparatus 5000 in Fig. 23, the tuner unit 3305 selectively receives the signal of the selected frequency channel (CH-Y), and down-converts it to a predetermined band. The A / D conversion unit 3308 performs A / D conversion and outputs a digital reception signal. The demodulation unit 3311 performs OFDM demodulation, and outputs the mapping data (cell) in the I-Q coordinates after equalization and the transmission path estimation value to the frequency deinterleaving unit 3315, and outputs the FFT output before equalization to the TMCC signal decoding unit 3335.

[0043] The TMCC signal decoding unit 3335 performs differential BPSK demodulation on the FFT output before equalization output from the demodulation unit 3311 for each carrier where the TMCC signal shown in Fig. 26 is arranged, and majority-decodes the demodulation results collected for each segment 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 reproduction unit 3331, and the FEC decoding unit 3333, and operations based on the TMCC signal decoded by each unit are performed.

[0044] The frequency deinterleaving unit 3315 performs frequency deinterleaving on the mapping data in the I-Q coordinates after equalization and the transmission path estimation value output from the demodulation unit 3311 for the partial reception unit, the differential modulation unit, and the synchronization modulation unit, respectively. The time deinterleaving unit 3321 performs time deinterleaving on the output from the frequency deinterleaving unit 3315.

[0045] FIG. 5 is a diagram showing the configuration of the multi-layer TS reproduction unit 3331. The multi-layer TS reproduction unit 3331 includes a demapping unit 3401, a bit deinterleaving unit 3411, a de-puncturing unit 3421, and a TS reproduction 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 estimation value. The bit deinterleaving unit 3411 performs bit deinterleaving, and the de-puncturing unit 3421 performs de-puncturing processing. The TS reproduction unit 3431 performs TS reproduction for each layer with respect to the output of the de-puncturing unit 3421.

[0046] FIG. 6 is a diagram showing the configuration of the FEC decoding unit 3333. The FEC decoding unit 3333 includes a Viterbi decoding unit 3441, a byte deinterleaving unit 3451, an energy despreading unit 3461, and an RS decoding unit 3471. With respect to the output from the multi-layer TS reproduction unit 3331, the Viterbi decoding unit 3441 performs Viterbi decoding, the byte deinterleaving unit 3451 performs byte deinterleaving, the energy despreading unit 3461 performs energy despreading, and the RS decoding unit 3471 performs RS decoding.

[0047] By the above operations, the ISDB-T receiving apparatus 3300 in FIG. 4 outputs the TSs of each layer of the ISDB-T system that have been subjected to error correction decoding for the signal transmitted from the transmitting apparatus 5000 in FIG. 23. Note that, among the components of the ISDB-T receiving apparatus 3300 in FIG. 4, the components excluding the tuner unit 3305 may be integrated as an integrated circuit 3341.

[0048] As shown in FIG. 3, the new broadcast system (LL signal) has lower power compared to the ISDB-T system (UL signal), and the range is from 17.5 dB to 25 dB. Since the required C / N of the current broadcast by the ISDB-T system is about 20 dB, the new broadcast system (LL signal) will be buried at a power level below the noise at the reception point near the required C / N. Therefore, the adverse effects on the existing ISDB-T receiving apparatus can be eliminated.

[0049] In addition, since addition in the LDM method is not performed on the SP signal, an existing ISDB-T receiver can perform accurate channel estimation, and as a result, decoding of the ISDB-T system (UL signal) can be performed accurately.

[0050] <Receiver and receiving method> FIG. 7 is a diagram showing the configuration of the receiver 3500 according to Embodiment 1 of the present invention. The receiver 3500 in FIG. 7 corresponds to the transmitter 3000 in FIG. 1 and reflects the functions of the transmitter 3000. The same components as those of the existing ISDB-T receiver are denoted by the same reference numerals, and the description thereof is omitted.

[0051] The receiver 3500 has a configuration in which the TMCC signal decoder 3335 is replaced with a TMCC signal decoder 3535 as compared with the ISDB-T receiver 3300 shown in FIG. 4. Further, a UL received signal reconstruction unit 3551, a delay unit 3553, a subtraction unit 3555, and an FEC decoder 3533 are added.

[0052] Hereinafter, the operation of the receiver 3500 will be described. When an analog RF transmission signal is input from the reception antenna Rx-1 to the signal transmitted from the transmitter 3000 in FIG. 1, the tuner unit 3305, the A / D conversion unit 3308, the demodulation unit 3311, the frequency deinterleaving unit 3315, the time deinterleaving unit 3321, the multi-layer TS reproduction unit 3331, and the FEC decoder 3333 perform the same operations as those of the ISDB-T receiver 3300 shown in FIG. 4, and output the TSs (UL decoded signals) of each layer of the ISDB-T system that have been subjected to error correction decoding from the FEC decoder 3333.

[0053] The TMCC signal decoder 3535 performs basically the same operation as the TMCC signal decoder 3335 in FIG. 4, and also has a function of outputting to the UL received signal construction unit 3551 and the FEC decoder 3533 including the new broadcast system bit groups B110 to B121 in the TMCC signal shown in FIG. 3.

[0054] Next, the UL received signal reconstruction unit 3551 reconstructs the received signal (the mapping data of the equalized I·Q coordinates) when transmitted only by UL, using the transmission path estimated value and the UL decoded signal output from the FEC decoder 3333.

[0055] The delay unit 3553 delays the equalized I·Q coordinate mapping data output from the time deinterleaver 3321 to align the 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 it as the received signal (the mapping data of the equalized I·Q coordinates) when transmitted only by LL.

[0056] FIG. 8 is a diagram showing the configuration of the FEC decoder 3533. The FEC decoder 3533 includes a demapping unit 3561, a bit deinterleaver 3563, an LDPC decoder 3565, a BCH decoder 3567, an energy despreading unit 3569, and a TS reproduction unit 3571.

[0057] When the received signal (the mapping data of the equalized I·Q coordinates) when transmitted only by LL is input from the subtraction unit 3555, the demapping unit 3561 performs demapping processing, the bit deinterleaver 3563 performs bit deinterleaving, the LDPC decoder 3565 performs LDPC decoding, the BCH decoder 3567 performs BCH decoding, the energy despreading unit 3569 performs energy despreading, and the TS reproduction unit 3571 performs TS reproduction. Through the above operations, the receiving apparatus 3500 in FIG. 7 outputs the TS (LL decoded signal) of each layer of the new broadcast system that has been subjected to error correction decoding for the signal transmitted from the transmitting apparatus 5000 in FIG. 23. Note that, among the components of the receiving apparatus 3500 in FIG. 7, the components excluding the tuner unit 3305 may be integrated as an integrated circuit 3541.

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

[0059] In addition, since addition in the LDM method is not performed on the SP signal, a receiving apparatus compatible with the new broadcast method can accurately perform transmission path estimation, and as a result, can accurately decode the UL signal and the LL signal.

[0060] (Embodiment 2) <Transmitting Apparatus and Transmitting Method> FIG. 9 is a diagram showing the configuration of a transmitting apparatus 3600 according to Embodiment 2 of the present invention. The same components as those of the conventional transmitting apparatus and the transmitting apparatus of Embodiment 1 are denoted by the same reference numerals, and the description thereof is omitted.

[0061] Compared with the transmitting apparatus 3000 in Embodiment 1 shown in FIG. 1, the transmitting apparatus 3600 in FIG. 9 has a configuration in which a TMCC / AC signal generation unit (for LL) 3691, a power difference control unit 3251, an addition unit 3261, and a power normalization unit 3271 are added.

[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 LL. The generated TMCC signal may be the same as the information shown in FIG. 3(b), or the number of bits of each parameter (such as the UL / LL signal power ratio) may be increased to increase the settable patterns. Alternatively, the types of parameters may be increased. The power difference control unit 3251, the addition unit 3261, and the power normalization unit 3271 perform the same operations as those in FIG. 2 on the outputs of the TMCC / AC signal generation unit 5091 and the TMCC / AC signal generation unit (for LL) 3691.

[0063] Note that if the TMCC / AC signal generation unit 5091 generates at least B110 (presence / absence of LDM transmission) among the information shown in FIG. 3(b), a receiving apparatus compatible with the new broadcast method can easily detect the presence / absence of LDM transmission. However, all or part of B110 to B121 may be generated.

[0064] The frame component 5101 constitutes an ISDB-T system transmission frame from the information data output from the frequency interleaving unit 5071, the pilot signal for synchronous reproduction 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 transmission device 3000 in the first embodiment shown in FIG. 1.

[0066] With the above configuration, by performing LDM addition on TMCC as well, the number of bits of TMCC (for LL) can be increased, and the flexibility of the new broadcast system can be enhanced. On the other hand, for existing ISDB-T receiving devices, since the received C / N of the information data and the TMCC signal can be observed at the same level, the detected received C / N value using the TMCC signal becomes the same level as the received C / N of the information data, and the adverse effects are eliminated.

[0067] <Existing ISDB-T Receiving Devices and Receiving Methods> The operation of the ISDB-T receiving device 3300 in FIG. 4 with respect to the signal transmitted from the transmission device 3600 in FIG. 9 is the same as the operation with respect to the signal transmitted from the transmission device 3000 in FIG. 1 in the first embodiment.

[0068] For the signal transmitted from the transmission device 3600 in FIG. 9, LDM addition is also performed on TMCC. However, the new broadcast system's TMCC (LL signal) has lower power compared to the ISDB-T system's TMCC (UL signal), and the range is from 17.5 dB to 25 dB. Since the required C / N for the current broadcast's TMCC by the ISDB-T system is approximately 10 dB, the new broadcast system's TMCC (LL signal) will be buried at a power level below the noise at the receiving point near the required C / N. Therefore, the adverse effects on existing ISDB-T receiving devices can be eliminated. Note that the range of the UL / LL signal power ratio for TMCC is not limited to 17.5 dB to 25 dB, and values smaller than this range may also be included in the range.

[0069] <Receiving Devices and Receiving Methods> FIG. 10 is a diagram showing the configuration of the receiving apparatus 3800 according to Embodiment 2 of the present invention. The receiving apparatus 3800 in FIG. 10 corresponds to the transmitting apparatus 3600 in FIG. 9 and reflects the functions of the transmitting apparatus 3600. The same components as those in the existing ISDB-T receiving apparatus and the receiving apparatus according to Embodiment 1 are denoted by the same reference numerals, and the description thereof is omitted.

[0070] Compared with the receiving apparatus 3500 according to Embodiment 1 shown in FIG. 7, the receiving apparatus 3800 has a configuration in which a UL received TMCC signal reconstruction unit 3851, a delay unit 3853, a subtraction unit 3855, and a TMCC signal decoding unit 3835 are added.

[0071] The operation of the receiving apparatus 3800 will be described below. The UL received TMCC signal reconstruction unit 3851 reconstructs a received TMCC signal (FFT output before equalization) in the case of transmission using only UL by using the channel estimation value and the UL TMCC decoded signal output from the TMCC signal decoding unit 3535.

[0072] The delay unit 3853 delays the FFT output before equalization output from the demodulation unit 3311 to match the 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 it as a received TMCC signal (FFT output before equalization) in the case of transmission using only LL.

[0073] The TMCC signal decoding unit 3835 performs basically the same operation as the TMCC signal decoding unit 3535, but also has a 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 apparatus 3500 according to Embodiment 1 shown in FIG. 7. Note that, among the components of the receiving apparatus 3800 in FIG. 10, components excluding the tuner unit 3305 may be integrated as an integrated circuit 3841.

[0075] With the above configuration, the receiving apparatus compatible with the new broadcast system can perform decoding of TMCC in which LDM addition is performed, and can decode the UL signal and the LL signal.

[0076] (Embodiment 3) <Transmitting Apparatus and Transmitting Method> FIG. 11 is a diagram showing the configuration of a transmitting apparatus 4000 according to Embodiment 3 of the present invention. The same components as those of the conventional transmitting apparatus and the transmitting apparatus of Embodiment 1 are denoted by the same reference numerals, and the description thereof is omitted.

[0077] The transmitting apparatus 4000 in FIG. 11 has a configuration in which 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 are added as compared with the transmitting apparatus 3000 in Embodiment 1 shown in FIG. 1.

[0078] In FIG. 11, the pilot signal generation unit (for LL addition) 4081 generates a pilot signal for synchronous reproduction using a pseudo-random binary sequence different from that of the pilot signal generation unit 5081. The power difference control unit 3251, the addition unit 3261, and the power normalization unit 3271 perform the same operations as those in FIG. 2 on 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 configures an ISDB-T system transmission frame from the information data output from the frequency interleaving unit 5071, the pilot signal for synchronous reproduction 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 transmitting apparatus 3000 in Embodiment 1 shown in FIG. 1.

[0081] With the above configuration, addition in the LDM method is also performed on pilot signals such as the SP signal. As a result, existing ISDB-T receivers can observe the reception C / N of information data and pilot signals at the same level. Therefore, the reception C / N detection value using the pilot signal becomes the same level as the reception C / N of information data, and adverse effects are eliminated. On the other hand, for receivers compatible with the new broadcast method, since the pilot signal on which the LDM method addition has been performed is known, channel estimation can be performed accurately, and as a result, decoding of the UL signal and the LL signal can be performed accurately.

[0082] <Existing ISDB-T Receiver and Reception Method> The operation of the ISDB-T receiver 3300 in FIG. 4 with respect to the signal transmitted from the transmitter 4000 in FIG. 11 is the same as the operation with respect to the signal transmitted from the transmitter 3000 in FIG. 1 in Embodiment 1.

[0083] The signal transmitted from the transmitter 4000 in FIG. 11 has addition in the LDM method performed on pilot signals such as the SP signal. However, for existing ISDB-T receivers, the reception C / N of information data and pilot signals can be observed at the same level. Therefore, the reception C / N detection value using the pilot signal becomes the same level as the reception C / N of information data, and adverse effects are eliminated.

[0084] <Receiver and Reception Method> FIG. 12 is a diagram showing the configuration of the receiver 4600 in Embodiment 3 of the present invention. The receiver 4600 in FIG. 12 corresponds to the transmitter 4000 in FIG. 11 and reflects the functions of the transmitter 4000. The same components as those of the existing ISDB-T receiver and the receivers in Embodiments 1 and 10 are denoted by the same reference numerals, and the description thereof is omitted.

[0085] The receiver 4600 has a configuration in which the demodulation unit 3311 is replaced with a demodulation unit 4611 as compared with the receiver 3500 in FIG. 7 in Embodiment 1.

[0086] In the receiving apparatus 4600 of FIG. 12, the demodulation unit 4611 performs OFDM demodulation using a known SP signal in consideration of the fact that the SP signals of the ISDB-T system and the new broadcast system generated using different pseudo-random binary sequences are added with a power difference.

[0087] Other operations are the same as those of the receiving apparatus 3500 in the first embodiment shown in FIG. 7. Note that, among the components of the receiving apparatus 4600 in FIG. 12, components excluding the tuner unit 3305 may be integrated as an integrated circuit 4641.

[0088] With the above configuration, the receiving apparatus compatible with the new broadcast system can perform OFDM demodulation using the pilot signal subjected to LDM system addition as a known signal, and can accurately decode the UL signal and the LL signal.

[0089] (Embodiment 4) <Transmitting Apparatus and Transmitting Method> FIG. 13 is a diagram showing the configuration of a transmitting apparatus 4100 according to Embodiment 4 of the present invention. The same components as those of the conventional transmitting apparatus and the transmitting apparatuses of Embodiments 1 to 3 are denoted by the same reference numerals, and the description thereof is omitted.

[0090] The transmitting apparatus 4100 in FIG. 13 has a configuration in which the hierarchical processing unit 3041 is replaced with a hierarchical processing unit 4141 as compared with the transmitting apparatus 3000 in the first embodiment shown in FIG. 1.

[0091] FIG. 14 is a diagram showing the configuration of the hierarchical processing unit 4141. As compared with the hierarchical processing unit 3041 in the first embodiment shown in FIG. 2, a selector 4145 is added.

[0092] When a selection signal “0” is input to the hierarchical processing unit 4141 in FIG. 14, the selector 4145 selects the output of the power normalization unit 3271. That is, the output of the hierarchical processing unit 4141 is the same as the output in FIG. 2.

[0093] When a selection signal "1" is input to the hierarchical processing unit 4141 in FIG. 14, the selector 4145 selects the output of the mapping unit 3241. That is, the output of the hierarchical processing unit 4141 is a carrier modulation signal (LL) of the new broadcast system, but the power cannot be reduced.

[0094] FIG. 15 shows a part of the definition of the TMCC signal. FIGS. 15(a) and 15(b) respectively show the definitions of B20 to B21 in the TMCC signal in the ISDB-T system and in the fourth embodiment. As shown in FIG. 15(b), in the fourth embodiment, for B20 to B21 = "10" which was undefined in the ISDB-T system, it is newly defined as the "Second-generation terrestrial digital television broadcast 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 transmission device 3000 in the first embodiment shown in FIG. 1.

[0096] With the above configuration, the hierarchical processing unit can select one of the signals of only the LDM method by the transmission device 3000 in the first embodiment shown in FIG. 1 and the new broadcast (LL signal) by the new broadcast method. Thus, it is possible to construct a system that anticipates that several years after the practical application of the LDM method, the current broadcast (UL signal) by the ISDB-T system will be stopped and only the new broadcast (LL signal) by the new broadcast method will remain.

[0097] <Existing ISDB-T receiving devices and receiving methods> Regarding the operation of the ISDB-T receiving device 3300 in FIG. 4 with respect to the signal transmitted from the transmission device 4300 in FIG. 13, only the differences from the operation with respect to the signal transmitted from the transmission device 3000 in FIG. 1 in the first embodiment will be described.

[0098] In the transmission device 4300 of FIG. 13, when B20 - B21 = "10" in the TMCC signal, the TMCC signal decoder 3335 in the ISDB-T reception device 3300 of FIG. 4 interprets the transmission signal as undefined and determines that reception is impossible.

[0099] On the other hand, in the transmission device 4300 of FIG. 13, when B20 - B21 = "00" in the TMCC signal, the TMCC signal decoder 3335 in the ISDB-T reception device 3300 of FIG. 4 interprets the transmission signal as a terrestrial digital television broadcast system (ISDB-T), performs the same operations as in Embodiment 1, and outputs the TS of each layer of the ISDB-T system that has been error-corrected and decoded up to error correction decoding.

[0100] <Reception Device and Reception Method> FIG. 16 is a diagram showing the configuration of the reception device 4700 in Embodiment 4 of the present invention. The reception device 4700 in FIG. 16 corresponds to the transmission device 4100 in FIG. 13 and reflects the functions of the transmission device 4100. The same components as those in the existing ISDB-T reception device and the reception devices of Embodiments 1 to 3 are denoted by the same reference numerals, and the description thereof is omitted.

[0101] The reception device 4700 has a configuration in which the TMCC signal decoder 3535 is replaced with a TMCC signal decoder 4735 and a selector 4145 is added as compared with the reception device 3500 in Embodiment 1 shown in FIG. 7.

[0102] Hereinafter, the operation of the reception device 4700 when B20 - B21 = "10" in the TMCC signal in the transmission device 4300 of FIG. 13 will be described. In this case, the TMCC signal decoder 4735 interprets the transmission signal as a second-generation terrestrial digital television broadcast system and outputs a selection signal "1" to the selector 4145.

[0103] The selector 4145 selects the output of the time deinterleaver 3321. That is, the output of the selector 4145 is the mapping data of the I·Q coordinates after equalization of the carrier modulation signal (LL) of the new broadcast system and the channel estimation value, and corresponds to the signal transmitted without reducing the power in the transmission device 4100 of FIG. 13.

[0104] The FEC decoding unit 3533 performs the same operation as in FIG. 7 to output the TS of each layer of the new broadcast system that has been subjected to error correction decoding.

[0105] Other operations are the same as those of the receiving apparatus 3500 in the first embodiment shown in FIG. 7. Note that, among the components of the receiving apparatus 4700 in FIG. 16, components excluding the tuner unit 3305 may be integrated as an integrated circuit 4741.

[0106] On the other hand, in the transmitting apparatus 4300 of FIG. 13, when B20 - B21 = “00” in the TMCC signal, the TMCC signal decoding unit 4735 interprets the transmission signal as a terrestrial digital television broadcast system and outputs a selection signal “0” to the selector 4145. Other operations are the same as those of the receiving apparatus 3500 in the first embodiment shown in FIG. 7, and the TS (UL decoded signal) of each layer of the ISDB-T system and the TS (LL decoded signal) of each layer of the new broadcast system are output.

[0107] With the above configuration, even when the current broadcast (UL signal) by the ISDB-T system is stopped several years after the practical application of the LDM method application method for the new broadcast system, and only the new broadcast (LL signal) by the new broadcast system remains, the receiving apparatus compatible with the new broadcast system can output the TS (LL decoded signal) of each layer of the new broadcast system. In particular, in this case, since the signal transmitted without reducing the power in the transmitting apparatus 4100 of FIG. 13 is received, the viewable area of the new broadcast system by the receiving apparatus 4700 is expanded.

[0108] (Embodiment 5) <Transmitting Apparatus and Transmitting Method> FIG. 17 is a diagram showing the configuration of a transmitting apparatus 4200 according to Embodiment 5 of the present invention. The same components as those of the conventional transmitting apparatus and the transmitting apparatuses of Embodiments 1 to 4 are denoted by the same reference numerals, and the description thereof is omitted.

[0109] The transmission device 4200 in FIG. 17 has a configuration in which the hierarchical synthesis unit 5051, the time interleaving unit 5061, the frequency interleaving unit 5071, the pilot signal generation unit 5081, the TMCC / AC signal generation unit 5091, the frame configuration unit 5101, and the OFDM signal generation unit 5111 are respectively replaced with the hierarchical synthesis unit 4251, the time interleaving unit 4261, the frequency interleaving unit 4271, the pilot signal generation unit 4281, the TMCC / AC signal generation unit 4291, the frame configuration unit 4301, and the OFDM signal generation unit 4311, as compared with the transmission device 4100 in Embodiment 4 shown in FIG. 13. 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 corresponding to the same values of the FFT size and GI as in the ISDB-T system (the FFT size has three types: 2k, 4k, 8k, and the GI has four types: 1 / 4, 1 / 8, 1 / 16, 1 / 32), similar to the transmission device 4100 in Embodiment 4 shown in FIG. 3.

[0111] On the other hand, for the case where the selection signal is "1", the operation of the transmission device 4200 will be described below. In this case, only the new broadcast (LL signal) by the new broadcast system is involved, and these processing units also operate corresponding to values different from the ISDB-T system (as an example, the FFT size has five types: 2k, 4k, 8k, 16k, 32k, and the GI has six types: 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, 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] Fig. 18 shows the segment configuration of the fifth embodiment by taking the synchronous modulation section with a selection signal of "1" and an FFT size of 32k as an example. As shown in Fig. 26, the segment of the synchronous modulation section with an FFT size of 2k is composed of 108 carriers. On the other hand, as shown in Fig. 18, when the FFT size is 32k, it is composed of 1728 carriers, which is 16 times that of the case with an FFT size of 2k. In Fig. 18, similar to Fig. 26, the SP signal is repeatedly arranged at a period of 4 symbols, and shifted by 3 carriers for each symbol. However, the arrangement pattern of the SP signal is not limited to this, and it may also be configured to be selected from multiple types. Also, the carriers of the TMCC signal and the AC signal are randomly arranged in the frequency direction in order to reduce the influence of the periodic dips in the transmission path characteristics due to multipath. The number of carriers per segment of the TMCC signal and the AC signal is 16 times that of the case with an FFT size of 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 respectively generate pilot signals for synchronous reproduction such as the SP signal and the TMCC / AC signal.

[0114] The frame configuration unit 4301 constitutes a transmission frame from the information data output from the frequency interleaving unit 4271, the pilot signal for synchronous reproduction 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 configuration unit 4301 also has processing functions for two types with FFT sizes of 16k and 32k.

[0115] The OFDM signal generation unit 4311 performs IFFT and inserts a GI (Guard Interval) on 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 with FFT sizes of 16k and 32k and two types with GIs of 1 / 64 and 1 / 128.

[0116] Other operations are the same as those of the transmission device 4100 in the fourth embodiment shown in Fig. 13.

[0117] With the above configuration, when it is possible to select either the LDM method by the transmission device 3000 in Embodiment 1 shown in FIG. 1 or only the signal of the new broadcast (LL signal) by the new broadcast method, several years after the practical application of the application method of the LDM method, the current broadcast (UL signal) by the ISDB-T method is stopped, and it is possible to construct a method anticipating that there will be only the new broadcast (LL signal) by the new broadcast method. In particular, when there is only the new broadcast (LL signal) by the new broadcast method, it becomes possible to operate with values of the FFT size and GI different from those of the ISDB-T method.

[0118] <Existing ISDB-T receiving device and receiving method> Regarding the operation of the ISDB-T receiving device 3300 in FIG. 4 with respect to the signal transmitted from the transmission device 4200 in FIG. 17, only the differences from the operation with respect to the signal transmitted from the transmission device 4100 in FIG. 13 in Embodiment 4 will be described.

[0119] In the transmission device 4200 in FIG. 17, when B20 - B21 = "10" in the TMCC signal, the ISDB-T receiving device 3300 cannot detect a signal transmitted with an FFT size different from that of the ISDB-T method (16k, 32k). The ISDB-T receiving device 3300 can perform TMCC signal decoding on a signal transmitted with an FFT size the same as that of the ISDB-T method (2k, 4k, 8k) and determines that it is impossible to receive, which is the same as in Embodiment 4. In both cases, it is determined that reception is impossible, but the former is determined due to the impossibility of signal detection, and the latter is determined based on the TMCC signal decoding result.

[0120] On the other hand, in the transmission device 4300 in FIG. 13, when B20 - B21 = "00" in the TMCC signal, the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 in FIG. 4 interprets the transmission signal as a terrestrial digital television broadcast system (ISDB-T), performs the same operation as in Embodiment 1, and outputs the TS of each layer of the ISDB-T method that has been subjected to error correction decoding.

[0121] <Receiving device and receiving method> FIG. 19 is a diagram showing the configuration of the receiving apparatus 4800 according to Embodiment 5 of the present invention. The receiving apparatus 4800 in FIG. 19 corresponds to the transmitting apparatus 4200 in FIG. 17 and reflects the functions of the transmitting apparatus 4200. The same components as those of the existing ISDB-T receiving apparatus and the receiving apparatuses according to Embodiments 1 to 4 are denoted by the same reference numerals, and the description thereof is omitted.

[0122] Compared with the receiving apparatus 4700 in Embodiment 4 shown in FIG. 16, the receiving apparatus 4800 has a configuration in which the demodulation unit 3311, the frequency deinterleaving unit 3315, the time deinterleaving unit 3321, and the TMCC signal decoding unit 4735 are replaced with a demodulation unit 4811, a frequency deinterleaving unit 4815, a time deinterleaving unit 4821, and a TMCC signal decoding unit 4835, respectively. A selection signal is generated by 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 manner as the receiving apparatus 4700 in Embodiment 4 shown in FIG. 16, and the values of the FFT size and the GI correspond to the same values as those in the ISDB-T system (the FFT size has three types: 2k, 4k, and 8k, and the GI has four types: 1 / 4, 1 / 8, 1 / 16, and 1 / 32). Therefore, the receiving apparatus 4800 outputs the TS (UL decoded signal) of each layer in the ISDB-T system and the TS (LL decoded signal) of each layer in the new broadcast system.

[0124] On the other hand, when the selection signal is "1" and only the new broadcast (LL signal) according to the new broadcast system is received, these processing units also operate corresponding to values different from those in the ISDB-T system (as an example, the FFT size has five types: 2k, 4k, 8k, 16k, and 32k, and the GI has six types: 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, and 1 / 128).

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

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

[0127] When the selection signal is "1", the frequency deinterleaving unit 4815 and the time deinterleaving unit 4821 also have processing functions 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 FIG. 16, and output the TS of each layer of the new broadcast system that has been subjected to error correction decoding. Note that, among the components of the receiving device 4800 in FIG. 17, components excluding the tuner unit 3305 may be included as the integrated circuit 4841.

[0129] With the above configuration, even when the current broadcast (UL signal) by the ISDB-T system is stopped several years after the practical application of the application method of the LDM system, and only the new broadcast (LL signal) by the new broadcast system remains, the receiving device compatible with the new broadcast system outputs the TS (LL decoded signal) of each layer of the new broadcast system. In particular, in this case, since the signal transmitted without reducing the power in the transmitting device 4200 in FIG. 17 is received, the viewable area of the new broadcast system by the receiving device 4800 is expanded, and the receiving device 4800 can operate corresponding to values of the FFT size and the GI different from those of the ISDB-T system.

[0130] (Embodiment 6) <Transmitting Device and Transmitting Method> FIG. 20 is a diagram showing the configuration of the transmitting device 4400 in Embodiment 6 of the present invention. The same components as those of the conventional transmitting device and the transmitting devices in Embodiments 1 to 5 are denoted by the same reference numerals, and the description thereof is omitted.

[0131] Compared with the transmission device 4100 in the fourth embodiment shown in FIG. 13, the transmission device 4400 in FIG. 20 adds a time interleaver 4461, a frequency interleaver 4471, a pilot signal generator 4481, a frame configurator 4501, a signaling generator 4541, a preamble generator 4551, and two selectors 4445-1 to 4445-2, and replaces the OFDM signal generator 5111 with the OFDM signal generator 4311 respectively. Based on whether the value of the selection signal is "0" or "1", either the signal of the LDM method by the transmission device 3000 in the first embodiment shown in FIG. 1 or only the signal of the new broadcast by the new broadcast method is selected as the output of the transmission device 4400.

[0132] When the selection signal is "0", the transmission signal of the LDM method by the transmission device 3000 in the first embodiment shown in FIG. 1 is selected and output from the transmission device 4400. In this case, similar to the transmission device 4100 in the fourth embodiment shown in FIG. 13, the values of the FFT size and the GI operate corresponding to the same values as the ISDB-T method (the FFT size has three types: 2k, 4k, 8k, and the GI has four types: 1 / 4, 1 / 8, 1 / 16, 1 / 32).

[0133] On the other hand, regarding the operation of the transmission device 4400 when the selection signal is "1", it will be described below. In this case, it also operates corresponding to values different from the ISDB-T method (as an example, the FFT size has five types: 2k, 4k, 8k, 16k, 32k, and the GI has six types: 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, 1 / 128). Furthermore, multiple layers are not divided in the frequency direction using the segment structure, but are divided in the time direction using a structure in which each layer is stored in a subframe.

[0134] When the selection signal is "1", the time interleaver 4461 and the frequency interleaver 4471 perform interleaving using the subframe structure instead of the interleaving using the segment structure. Note that it also has processing functions for two types of FFT sizes: 16k and 32k.

[0135] Fig. 21 shows the SP signal arrangement pattern of Embodiment 6 when the selection signal is "1". As shown in Fig. 21, similar to Figs. 18 and 78, the SP signals are arranged repeatedly with a period of 4 symbols, and are shifted and arranged by 3 carriers for each symbol. However, the arrangement pattern of the SP signals is not limited to this, and it may also be configured to be selected from multiple types. Also, carriers for the TMCC signal and the AC signal are not provided. In this way, the pilot signal generation unit 4481 generates a pilot signal for synchronous reproduction such as the SP signal.

[0136] The frame configuration unit 4501 configures a transmission frame from the information data output from the frequency interleaving unit 4471 and the pilot signal for synchronous reproduction output from the pilot signal generation unit 4481. In each transmission frame, the frame configuration unit 4501 stores the information data of each layer in sub-frames.

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

[0138] The OFDM signal generation unit 4311 performs IFFT and GI insertion on the transmission frame configuration output from the 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 functions for two types with FFT sizes of 16k and 32k and two types with GIs of 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 head 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 transmission device 4100 in Embodiment 4 shown in Fig. 13.

[0142] With the above configuration, when it is possible to select either the LDM method by the transmission device 3000 in Embodiment 1 shown in FIG. 1 or only the signal of the new broadcast (LL signal) by the new broadcast method, several years after the practical application of the application method of the LDM method, the current broadcast (UL signal) by the ISDB-T method is stopped, and it is possible to construct a method that anticipates that there will be only the new broadcast (LL signal) by the new broadcast method. In particular, when there is only the new broadcast (LL signal) by the new broadcast method, it becomes possible to operate with values of the FFT size and GI different from those of the ISDB-T method, and it is also possible to divide in the time direction using a structure in which each layer is stored in a subframe.

[0143] <Existing ISDB-T Receiving Device and Receiving Method> Regarding the operation of the ISDB-T receiving device 3300 in FIG. 4 with respect to the signal transmitted from the transmission device 4400 in FIG. 20, only the differences from the operation with respect to the signal transmitted from the transmission device 4100 in FIG. 13 in Embodiment 4 will be described.

[0144] When the selection signal is "1" in the transmission device 4400 in FIG. 20, the ISDB-T receiving device 3300 cannot detect the signal transmitted in the time-division frame structure using the preamble and subframe.

[0145] On the other hand, when the selection signal is "0" in the transmission device 4400 in FIG. 20, the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 in FIG. 4 interprets the transmission signal as a terrestrial digital television broadcast system (ISDB-T), performs the same operation as in Embodiment 1, and outputs the TS of each layer of the ISDB-T method that has been subjected to error correction decoding.

[0146] <Receiving Device and Receiving Method> FIG. 22 is a diagram showing the configuration of the receiving apparatus 4900 in Embodiment 6 of the present invention. The receiving apparatus 4900 in FIG. 22 corresponds to the transmitting apparatus 4400 in FIG. 20 and reflects the functions of the transmitting apparatus 4400. The same components as those of the existing ISDB-T receiving apparatus and the receiving apparatuses in Embodiments 1 to 5 are denoted by the same reference numerals, and the description thereof is omitted.

[0147] Compared with the receiving apparatus 3500 in Embodiment 1 shown in FIG. 7, the receiving apparatus 4900 adds a frequency deinterleaving unit 4915, a time deinterleaving unit 4921, a preamble detection unit 4961, and a selector 4945, and has a configuration in which the demodulation unit 3311 is replaced with a demodulation unit 4811.

[0148] When the selection signal is “0” in the transmitting apparatus 4400 in FIG. 20, the receiving apparatus 4900 in FIG. 22 performs the same operation as the receiving apparatus 3500 in Embodiment 1 shown in FIG. 7, and outputs the TS (UL decoded signal) of each layer of the ISDB-T system and the TS (LL decoded signal) of each layer of the new broadcast system. Note that the receiving apparatus 4900 operates corresponding to the same values of the FFT size and the GI as those of the ISDB-T system (the FFT size has three types: 2k, 4k, and 8k, and the 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 apparatus 4400 in FIG. 20, the operation of the receiving apparatus 4900 will be described below.

[0150] The preamble detection unit 4961 detects a preamble from the digital reception signal of the A / D conversion unit 3308, and outputs the signaling of the new broadcast system included in the preamble.

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

[0152] With respect to the output of the demodulation unit 4811, the frequency deinterleaving unit 4915 and the time deinterleaving unit 4921 perform deinterleaving using a subframe structure.

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

[0154] For other operations, the same operations as those of the receiving apparatus 3500 in the first embodiment shown in FIG. 7 are performed, and the TSs of each layer of the new broadcast system that have been subjected to error correction decoding are output. Note that, among the components of the receiving apparatus 4900 in FIG. 22, components excluding the tuner unit 3305 may be integrated as an integrated circuit 4941.

[0155] With the above configuration, even when the current broadcast (UL signal) by the ISDB-T system is stopped several years after the practical application of the application method of the LDM system and only the new broadcast (LL signal) by the new broadcast system remains, the receiving apparatus compatible with the new broadcast system outputs the TSs (LL decoded signals) of each layer of the new broadcast system. In particular, in this case, since the signal transmitted without reducing the power by the transmitting apparatus 4400 in FIG. 20 is received, the viewable area of the new broadcast system by the receiving apparatus 4900 is expanded, and the receiving apparatus 4900 can operate corresponding to values of the FFT size and the GI different from those of the ISDB-T system. Further, in this case, the receiving apparatus 4900 can also operate corresponding to the transmitted signal divided in the time direction using a structure in which each layer is stored in a subframe.

[0156] (Supplementary Note) The present disclosure is not limited to the contents described in the above first to sixth embodiments, and can be implemented in any form for achieving the object of the present disclosure and related or incidental objects thereto. For example, the following may be applicable.

[0157] (1) In the first to sixth embodiments, the input to the transmitting apparatus for the new broadcast system is the TS, but the present disclosure is not limited thereto. For example, IP packets, MMT (MPEG Media Transport), or packets encapsulating them may be used.

[0158] (2) In Embodiments 1 to 5, the definitions of B110 to B121 in the TMCC signal are as shown in FIG. 3, but are not limited thereto. The UL / LL signal power ratio, the carrier modulation mapping method of each layer LL signal, and the value of the LDPC coding rate of each layer LL signal may be different from those in FIG. 3.

[0159] (3) In Embodiments 4 to 6, as values different from the ISDB-T method, the FFT sizes are five types: 2k, 4k, 8k, 16k, and 32k, and the GIs are six types: 1 / 4, 1 / 8, 1 / 16, 1 / 32, 1 / 64, and 1 / 128. However, this is only an example and is not limited thereto.

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

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

[0162] (6) The above Embodiments 1 to 6 may relate to an implementation using hardware and software. The above embodiments 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 above embodiments may be executed or realized by the combination of these devices.

[0163] (7) Embodiments 1 to 6 may be implemented by a software module mechanism executed by a processor or directly by hardware. Also, a combination of software modules and hardware implementation is possible. The software module may be stored in various types of computer-readable storage media, such as RAM, EPROM, EEPROM, flash memory, registers, hard disk, CD-ROM, DVD, etc.

Industrial Applicability

[0164] The transmission device, transmission method, reception device, reception method, integrated circuit, and program according to the present disclosure can be applied to wireless transmission systems.

Explanation of Signs

[0165] 3000, 3600, 4000, 4100, 4200, 4400, 5000 Transmission device 3500, 3800, 4600, 4700, 4800, 4900 Reception device 3341, 3541, 3841, 4641, 4741, 4841, 4941 Integrated circuit 3300 ISDB-T reception device 5011 TS remultiplexing unit 5021 RS encoding unit 5031 Hierarchical division unit 3041, 4141, 5041 Hierarchical processing unit 4251, 5051 Hierarchical synthesis unit 4261, 4461, 5061 Time interleaving unit 3321, 4821, 4921 Time deinterleaving unit 4271, 4471, 5071 Frequency interleaving unit 3315, 4815, 4915 Frequency deinterleaving unit 3081, 4281, 4481, 5081 Pilot signal generation unit 4081 Pilot signal generation unit (for LL addition) 4291, 5091 TMCC / AC signal generation unit 3691 TMCC / AC Signal Generation Unit (for LL) 4301, 4501, 5101 Frame Composition Unit 4311, 5111 OFDM Signal Generation Unit 5121 D / A Conversion Unit 5131 Frequency Conversion Unit 3201, 5201 Energy Diffusion Unit 3461, 3569 Energy Inverse Diffusion Unit 5211 Byte Interleaving Unit 3451 Byte Deinterleaving Unit 5221 Convolution Encoding Unit 3231, 5231 Bit Interleaving Unit 3411, 3563, 3911 Bit Deinterleaving Unit 3241, 5241 Mapping Unit 3401, 3561 Demapping Unit 3211 BCH Encoding Unit 3567 BCH Decoding Unit 3221 LDPC Encoding Unit 3565 LDPC Decoding Unit 3251 Power Difference Control Unit 3261 Addition Unit 3271 Power Normalization Unit 3305 Tuner Unit 3308 A / D Conversion Unit 4611, 4811 Demodulation Unit 3331 Multi - layer TS Reproduction Unit 3333, 3533 FEC Decoding Unit 3335, 3535, 3835, 4735, 4835 TMCC Signal Decoding Unit 3421 Depuncturing Unit 3431, 3571 TS Reproduction Unit 3441 Viterbi Decoding Unit 3551 UL Received Signal Reconstruction Unit 3851 UL Received TMCC Signal Reconstruction Unit 3555, 3855 Subtraction Unit 3553, 3853 Delay Unit 4145, 4445, 4945 Selector 4551 Preamble Generation Unit 4961 Preamble Detection Unit 5301 Segment Division Unit 5311 Inter - segment Interleaving Unit 5321 In - segment Carrier Rotation Unit 5331 In - segment Carrier Randomization Unit

Claims

1. A transmission 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 superposition coding, a first bit interleaving unit that generates a first bit sequence of the first data sequence by performing bit interleaving on the first data sequence; a second bit interleaving unit that generates a second bit sequence of the second data sequence by performing bit interleaving on the second data sequence; a first mapping unit that generates a first modulated symbol sequence of the first data sequence by mapping the first bit sequence of the first data sequence; a second mapping unit that generates a second modulated 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 superposing the first modulated symbol sequence and the second modulated 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 that is not used in a first communication standard and is used in a second communication standard different from the first communication standard among a predetermined bit array. Transmission device.

2. A receiving device that receives a transmission signal including a multiplexed signal in which a first modulated symbol sequence generated from a first data sequence of a first layer and a second modulated symbol sequence generated from a second data sequence of a second layer are multiplexed by superposition coding, and a control signal generated from control information indicating the multiplexing method, a receiving unit that receives the transmission signal to obtain a received signal; a control information acquisition unit that demodulates the received signal corresponding to the control signal to obtain 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 that generates a bit sequence from the output of the first demodulation unit; a bit interleaving unit that generates the first modulated symbol sequence by performing bit interleaving on the bit sequence. a delay unit that delays a received signal corresponding to the multiplexed signal by a predetermined time delay; a subtraction unit that subtracts components of the first modulated symbol sequence from the received signal corresponding to the multiplexed signal delayed by the delay unit; a second demodulation unit that demodulates the received signal corresponding to the multiplexed signal from which the components of the first modulated symbol sequence have been subtracted based on the control information to obtain a second data sequence; and the control signal included in the transmission signal is not superimposed on other signals; the control information includes information indicating that the second data sequence is multiplexed on the multiplexed signal; the information is indicated by a flag set at a bit position that is not used in a first communication standard and is used in a second communication standard different from the first communication standard among a predetermined bit array; a receiving device.

Images