JP7670748B2 - Transmitting device, receiving device, and program - Google Patents

Description

The present invention relates to wireless transmission technology.

Analogue terrestrial television broadcasting in Japan ended in July 2011 and has been completely switched to digital broadcasting. In Japan, HDTV services are provided using the ISDB-Terrestrial (ISDB-Terrestrial) system as the transmission standard. The ISDB-T system uses the Orthogonal Frequency Division Multiplexing (OFDM) system (Non-Patent Document 1).

ARIB Standard ARIB STD-B31 Version 2.2 (March 2014): Transmission method for terrestrial digital television broadcasting "A Study on the Application of LDM System to Digital Terrestrial TV Broadcasting", EIGA Technical Report, Vol. 40, No. 35, pp. 1-4, (Oct. 2016)

In general, there is a demand for larger capacity in wireless transmission. Therefore, the present disclosure aims to provide a transmitting device, a receiving device, a transmitting method, and a receiving method that, when implemented in combination with a current service in wireless transmission, can increase the transmission capacity compared to the current service without using other frequency bands.

In order to achieve the above object, a transmitting device according to an aspect of the present disclosure includes: a TMCC signal generating unit that generates a parameter for identifying a broadcasting system, the parameter being provided in a Transmission Multiplexing Configuration Control (TMCC) signal; and a transmitting unit that transmits a signal to be broadcasted and the TMCC signal. When the TMCC signal generating unit sets a first value indicating a first broadcasting system to the parameter, the transmitting unit transmits the signal of the first broadcasting system as an Upper Multiplexing (Upper Multiplexing) signal.
a signal generated in a Layered Division Multiplexing (LDM) scheme in which a signal of a first broadcasting system is a Lower Level (UL) signal and a signal of a second broadcasting system that will be standardized after the standardization of the first broadcasting system is a Lower Level (LL) signal, and when the TMCC signal generating unit sets a second value indicating the second broadcasting system to the parameter, the transmitting unit transmits only the signal of the second broadcasting system.

When the above-mentioned transmitting device is used in combination with an existing service in wireless transmission, it is possible to increase the transmission capacity compared to the existing service without using other frequency bands.

A diagram showing the configuration of a transmitting device 3000 in embodiment 1. FIG. 2 is a diagram showing a configuration of a hierarchy processing unit 3041 in the first embodiment. FIG. 2 is a diagram showing a part of the definition of a TMCC signal in the first embodiment. FIG. 33 is a diagram showing the configuration of an existing ISDB-T receiving device 3300 in the first embodiment. A diagram showing the configuration of a multi-layer TS playback unit 3331 in embodiment 1. FIG. 13 is a diagram showing a configuration of an FEC decoding unit 3333 in the first embodiment. A diagram showing the configuration of a receiving device 3500 in embodiment 1. FIG. 13 is a diagram showing a configuration of an FEC decoding unit 3533 in the first embodiment. A diagram showing the configuration of a transmitting device 3600 in embodiment 2. A diagram showing the configuration of a receiving device 3800 in embodiment 2. A diagram showing the configuration of a transmitting device 4000 in embodiment 3. A diagram showing the configuration of a receiving device 4600 in embodiment 3. A diagram showing the configuration of a transmitting device 4100 in embodiment 4. FIG. 13 is a diagram showing the configuration of a hierarchy processing unit 4141 in the fourth embodiment. A figure showing part of the definition of a TMCC signal in embodiment 4. A diagram showing the configuration of a receiving device 4700 in embodiment 4. A diagram showing the configuration of a transmitting device 4200 in embodiment 5. A diagram showing a segment configuration in embodiment 5. A diagram showing the configuration of a receiving device 4800 in embodiment 5. A diagram showing the configuration of a transmitting device 4400 in embodiment 6. A figure showing an SP signal arrangement pattern when the selection signal in embodiment 6 is "1". A diagram showing the configuration of a receiving device 4900 in embodiment 6. A diagram showing the configuration of a transmitting device 5000 in the ISDB-T system. A diagram showing the configuration of a hierarchical processing unit 5041 in the ISDB-T system. A diagram showing the configuration of a frequency interleaving unit 5071 in the ISDB-T system. FIG. 1 is a diagram showing the segment configuration of the ISDB-T system.

Figure 23 is a diagram showing the configuration of a 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 generating unit 5081, a TMCC (Transmission Multiplexing Configuration Control)/AC (Auxiliary Channel) signal generating unit 5091, a frame configuration unit 5101, an OFDM signal generating unit 5111, a D/A conversion unit 5121, and a frequency conversion unit 5131.

The operation of the transmitting device 5000 will be described below. Multiple TSs output from an MPEG-2 multiplexing unit (not shown) are input to a TS remultiplexing unit 5011 to arrange the TS packets in a manner suitable for signal processing in data segment units. The TS remultiplexing unit 5011 converts the TS into a single TS in a burst signal format in 188-byte units 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 a maximum of three systems (hierarchical layer A, hierarchical layer B, and hierarchical layer C) in accordance with the hierarchical information.

Figure 24 is a diagram showing the configuration of the hierarchical processing unit 5041. The hierarchical processing unit 5041 includes 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 mainly performs digital data processing such as error correction coding and interleaving, and carrier modulation on the input hierarchical data. Error correction, interleave length, and carrier modulation method are set independently for each hierarchical layer.

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

Figure 25 is a diagram showing the configuration of the frequency interleaving unit 5071. The frequency interleaving unit 5071 includes a segment division unit 5301, an inter-segment interleaving unit 5311-D and S, an intra-segment carrier rotation unit 5321-P, D and S, and an intra-segment carrier randomization unit 5331-P, D and S. In order to effectively utilize the capabilities of error correction coding against electric field fluctuations and multipath interference in mobile reception, the time interleaving unit 5061 performs convolution interleaving within the segment on the output from the hierarchical synthesis unit 5051, and the frequency interleaving unit 5071 performs interleaving between and within the segment. 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 (segments in which carrier modulation is specified as DQPSK), and synchronous modulation unit (segments in which 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 layer are arranged consecutively in numerical order, with the layers containing the smallest data segment numbers being layer A, layer B, and layer C. Even if the layers are different, interleaving is performed on data segments that belong to the same type of modulation unit.

In FIG. 23, pilot signal generator 5081 generates a pilot signal for synchronous reproduction. For hierarchical transmission in which multiple transmission parameters are mixed, TMCC/AC signal generator 5091 generates a TMCC signal, which is control information, and an AC signal, which is additional information, to assist the receiving device in demodulating and decoding. Frame constructor 5101 constructs an ISDB-T transmission frame from the information data output from frequency interleaving unit 5071, the pilot signal for synchronous reproduction output from pilot signal generator 5081, and the TMCC signal output from TMCC/AC signal generator 5091.

Figure 26 shows the segment configuration of the ISDB-T system, taking the synchronous modulation section (QPSK, 16QAM, 64QAM) of mode 1 (FFT size is 2k) as an example. Scattered pilot signals (hereinafter SP signals: Scattered Pilot signals) as pilot signals for synchronous reproduction are not transmitted for each subcarrier, but are transmitted in the frequency (subcarrier) direction and time (symbol) direction at carrier positions where carrier number k satisfies k = 3 (n mod 4) + 12p (mod represents modulus operation, and p is an integer) for the symbol with symbol number n. That is, as shown in Figure 26, the SP signal is repeatedly arranged with a period of 4 symbols, and is shifted by 3 carriers for each symbol. The SP signal arranged in this way is modulated to two values with a specific pattern determined by the carrier position, and then transmitted. The carriers of the TMCC signal and the AC signal are also arranged randomly 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 modulated and transmitted using modulation methods such as QPSK, 16QAM, and 64QAM using carriers that do not contain SP signals, TMCC signals, and AC signals.

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

In recent years, there has been active research into UHDTV (Ultra HDTV) 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 large-capacity transmission with higher frequency utilization efficiency than the ISDB-T method. As a method for performing large-capacity transmission without using other frequency bands while continuing the current broadcasting services using the ISDB-T method, a method is being studied that applies the LDM (Layered Division Multiplexing) method to the current ISDB-T broadcasting services to increase transmission capacity (Non-Patent Document 2).

In Non-Patent Document 2, a large signal level is assigned to the transmission RF signal of the current broadcast using the ISDB-T system, and a small signal level is assigned to the transmission RF signal of the new broadcast system (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.

A receiving device compatible with the new broadcasting standard first decodes the UL data from the received RF signal, and then uses the transmission path estimation value at that time to reconstruct the RF received signal as it would be if it were transmitted only via UL.The reconstructed UL RF received signal is then subtracted from the received RF signal to extract the RF received signal as it would be if it were transmitted only via LL, and the LL data is decoded.

When receiving only UL signals, the LL signals can be considered as noise, so no special processing such as the reconstruction or subtraction mentioned above is required. Therefore, this also applies to existing receiving devices that are compatible with current broadcasts using the ISDB-T standard.

In Non-Patent Document 2, the possibility of applying this type of LDM method to continue current broadcasting using the ISDB-T system and transmitting large volumes of data without using other frequency bands is examined.

However, in order to apply this type of LDM method, a method must be developed that allows receivers compatible with the new broadcasting system to accurately decode UL and LL signals, and that method must also eliminate any adverse effects on existing receivers compatible with the current broadcasting system. In addition, it is necessary to develop a method that takes into account the possibility that several years after this type of LDM method is put into practical use, the current broadcasting (UL signals) using the ISDB-T system will be discontinued, and only new broadcasting (LL signals) using the new broadcasting system will be available.

The inventions according to the first to sixth embodiments described below have been made to solve the above-mentioned problems, and aim to provide a transmitting device, a transmitting method, a receiving device, a receiving method, an integrated circuit, and a program that use the new LDM method for current broadcasting.

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

(Embodiment 1)
<Transmitting device and transmitting method>
1 is a diagram showing the configuration of a transmission device 3000 according to a first embodiment of the present invention. The same components as those in a conventional transmission device are given the same reference numerals, and the description thereof will be omitted.

Compared to the conventional transmitting device 5000 shown in FIG. 23, the transmitting device 3000 shown in FIG. 1 has a configuration in which the hierarchical processing units 5041-A to C are replaced with hierarchical processing units 3041-A to C.

The operation of the transmitting device 3000 will be described below. Multiple TSs for the new broadcasting system output from an MPEG-2 multiplexing unit (not shown) are input as LL signals to the hierarchical processing units 3041-A to 3041-C, respectively. On the other hand, multiple TSs 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 FIG. 23.

Figure 2 is a diagram showing the configuration of the hierarchical processing unit 3041. Compared to the conventional hierarchical processing unit 5041 shown in Figure 24, the configuration adds an energy dispersal 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.

In the hierarchical processing unit 3041 in FIG. 2, when a UL signal is input from the hierarchical division unit 5031, the energy diffusion unit 5201, the byte interleaving unit 5211, the convolutional coding unit 5221, the bit interleaving unit 5231, and the mapping unit 5241 perform processing similar to that of the conventional hierarchical processing unit 5041 shown in FIG. 24.

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

Based on the LL signal power instruction signal, the power difference control unit 3251 reduces the power of the carrier modulation signal (LL) output from the mapping unit 3241 to be lower than the power of the carrier modulation signal (UL) output from the mapping unit 5241.

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

The power normalization unit 3271 normalizes the power of the output signal of the addition unit 3261 based on the LL signal power instruction signal so that the power is the same as the power of the carrier modulation signal (UL) output from the mapping unit 5241.

In the transmitting device 3000 in Fig. 1, the hierarchical synthesis unit 5051 and subsequent units operate in the same manner as the conventional transmitting device 5000 shown in Fig. 23. However, as will be described later with reference to Fig. 3 (part of the definition of the TMCC signal), some changes are made to the definition of the TMCC signal in the ISDB-T system in order to apply the LDM method performed by the hierarchical processing unit 3041 in Fig. 2.

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

- B110: "0" indicates that LDM transmission is present, and "1" indicates that LDM transmission is not present (ISDB-T system only). This allows receivers compatible with the new broadcasting system to recognize the presence or absence of LDM transmission without adversely affecting existing ISDB-T receivers.

When B110 is "0", in this embodiment 1, B111 to B121, which are undefined (all "1") in the ISDB-T system, are changed as follows:

B111 to B112: 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: Represents the carrier modulation mapping method of 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.

With the above configuration, the hierarchical synthesis unit 5051 and subsequent units operate in the same way as the ISDB-T system, and by assigning control information related to LDM transmission to bit groups that were undefined in the TMCC signal of the ISDB-T system, it is possible to eliminate adverse effects on existing receiving devices that are compatible with current broadcasting.

In addition, in Non-Patent Document 2, the UL and LL transmission RF signals are simply added together, so the added transmission signal has poor accuracy for the LDM method. On the other hand, in this embodiment 1, LDM method addition is not performed on the SP signal in particular, so the transmission signal has good accuracy for the LDM method. Therefore, both existing receiving devices compatible with current broadcasting and receiving devices compatible with the new broadcasting method can perform transmission path estimation with high accuracy. As a result, receiving devices compatible with the new broadcasting method in particular can decode UL and LL signals with high accuracy.

<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.

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.

The operation of the ISDB-T receiving device 3300 will be described below. When an analog RF transmission signal is input from the receiving antenna Rx-1 in response to the signal transmitted from the transmitting device 5000 in FIG. 23, the tuner unit 3305 selects and receives the signal of the selected frequency channel (CH-Y) and down-converts it to a specified band. The A/D conversion unit 3308 performs A/D conversion and outputs a digital received signal. The demodulation unit 3311 performs OFDM demodulation, and outputs the mapping data (cell) of 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.

The TMCC signal decoding unit 3335 performs differential BPSK demodulation on each carrier on which the TMCC signal shown in FIG. 26 is placed on the FFT output before equalization output from the demodulation unit 3311, and performs majority voting decoding on 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 each unit performs an operation based on the decoded TMCC signal.

The frequency deinterleaving unit 3315 performs frequency deinterleaving on the equalized I/Q coordinate mapping data and transmission path estimation value output from the demodulation unit 3311 for the partial reception unit, differential modulation unit, and synchronous modulation unit. The time deinterleaving unit 3321 performs time deinterleaving on the output from the frequency deinterleaving unit 3315.

Figure 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 depuncturing unit 3421, and a TS reproduction unit 3431. The demapping unit 3401 performs demapping processing based on the mapping data of the I and Q coordinates after equalization rearranged by the frequency deinterleaving unit 3315 and the time deinterleaving unit 3321 and the transmission channel estimation value. The bit deinterleaving unit 3411 performs bit deinterleaving, and the depuncturing unit 3421 performs depuncturing. The TS reproduction unit 3431 performs TS reproduction for each layer from the output of the depuncturing unit 3421.

Figure 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. For the output from the multi-layer TS playback 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.

By the above operation, the ISDB-T receiving device 3300 in FIG. 4 outputs TS of each layer of the ISDB-T system that has been subjected to error correction decoding for the signal transmitted from the transmitting device 5000 in FIG. 23. Note that the components of the ISDB-T receiving device 3300 in FIG. 4, excluding the tuner unit 3305, may be included in an integrated circuit 3341.

As shown in Figure 3, the new broadcasting system (LL signal) has a lower power than the ISDB-T system (UL signal), ranging from 17.5 dB to 25 dB. Since the required C/N for current ISDB-T broadcasting is approximately 20 dB, the new broadcasting system (LL signal) will be buried at a power level below the noise at receiving points near the required C/N. This makes it possible to eliminate any adverse effects on existing ISDB-T receiving equipment.

In addition, since no LDM method addition is performed on the SP signal, existing ISDB-T receiving devices can perform transmission path estimation with high accuracy, and as a result, can decode the ISDB-T system (UL signal) with high accuracy.

<Receiving device and receiving method>
Fig. 7 is a diagram showing the configuration of a receiving device 3500 in the first embodiment of the present invention. The receiving device 3500 in Fig. 7 corresponds to the transmitting device 3000 in Fig. 1, and reflects the functions of the transmitting device 3000. The same components as those in the existing ISDB-T receiving device are designated by the same reference numerals, and the description thereof will be omitted.

Compared to the ISDB-T receiving device 3300 shown in FIG. 4, the receiving device 3500 has a configuration in which the TMCC signal decoding unit 3335 is replaced with a TMCC signal decoding unit 3535. In addition, a UL received signal reconstruction unit 3551, a delay unit 3553, a subtraction unit 3555, and an FEC decoding unit 3533 are added.

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 in response to the signal transmitted from the transmitting device 3000 in FIG. 1, the tuner unit 3305, A/D conversion unit 3308, demodulation unit 3311, frequency deinterleaving unit 3315, time deinterleaving unit 3321, multi-layer TS reproduction unit 3331, and FEC decoding unit 3333 perform the same operations as the ISDB-T receiving device 3300 shown in FIG. 4, and the FEC decoding unit 3333 outputs the TS (UL decoded signal) of each layer of the ISDB-T system that has been subjected to error correction decoding.

Note that the TMCC signal decoding unit 3535 basically performs the same operation as the TMCC signal decoding unit 3335 in FIG. 4, but also has the function of outputting the new broadcasting system bit group B110 to B121 in the TMCC signal shown in FIG. 3 to the UL received signal construction unit 3551 and the FEC decoding unit 3533.

The UL received signal reconstruction unit 3551 then 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 I and Q coordinates after equalization) when transmitted only via UL.

The delay unit 3553 delays the mapping data of the equalized I and Q coordinates output from the time deinterleaving unit 3321, and aligns 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 the result as the received signal (mapping data of the equalized I and Q coordinates) when transmitted only by LL.

Figure 8 shows the configuration of the FEC decoding unit 3533. The FEC decoding unit 3533 is composed of a demapping unit 3561, a bit deinterleaving unit 3563, an LDPC decoding unit 3565, a BCH decoding unit 3567, an energy despreading unit 3569, and a TS reproduction unit 3571.

When the received signal (mapping data of I and Q coordinates after equalization) transmitted only by LL is input from the subtraction unit 3555, the demapping unit 3561 performs demapping processing, 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 reproduction unit 3571 performs TS reproduction. Through the above operations, the receiving device 3500 in FIG. 7 outputs TS (LL decoded signal) of each layer of the new broadcasting method that has been subjected to error correction decoding for the signal transmitted from the transmitting device 5000 in FIG. 23. Note that the components of the receiving device 3500 in FIG. 7 except for the tuner unit 3305 may be included in the integrated circuit 3541.

With the above configuration, a receiving device compatible with the new broadcasting system can detect control information related to LDM transmission that is assigned to bit groups that were undefined in the TMCC signal of the ISDB-T system, and decode the UL signal and LL signal.

In addition, since no LDM method addition is performed on the SP signal, a receiving device compatible with the new broadcasting system can perform transmission path estimation with high accuracy, and as a result, can decode the UL signal and LL signal with high accuracy.

(Embodiment 2)
<Transmitting device and transmitting method>
9 is a diagram showing the configuration of a transmission device 3600 according to the second embodiment of the present invention. The same components as those in the conventional transmission device and the transmission device according to the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

Compared to the transmitting device 3000 in the first embodiment shown in FIG. 1, the transmitting device 3600 in FIG. 9 has a configuration in which a TMCC/AC signal generating unit (for LL) 3691, a power difference control unit 3251, an adding unit 3261, and a power normalization unit 3271 are added.

The TMCC/AC signal generator (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 settable patterns may be increased by increasing the number of bits of each parameter (UL/LL signal power ratio, etc.). Alternatively, the number of types of parameters may be increased. The power difference controller 3251, adder 3261, and power normalizer 3271 perform the same operations as in FIG. 2 on the outputs of the TMCC/AC signal generator 5091 and the TMCC/AC signal generator (for LL) 3691.

When the TMCC/AC signal generating unit 5091 generates at least B110 (presence or absence of LDM transmission) of the information shown in FIG. 3(b), a receiving device compatible with the new broadcasting system can easily detect the presence or absence of LDM transmission. However, it may generate all or part of B110 to B121.

The frame configuration unit 5101 configures an ISDB-T 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.

Other operations are the same as those of the transmitting device 3000 in embodiment 1 shown in Figure 1.

With the above configuration, by adding the LDM method to TMCC as well, the number of bits for TMCC (for LL) can be increased, enhancing the flexibility of the new broadcasting method. On the other hand, for existing ISDB-T receiving devices, the received C/N ratios of information data and TMCC signals can be observed at the same level, so the received C/N ratio detection value using the TMCC signal is at the same level as the received C/N ratio of information data, eliminating any adverse effects.

<Existing ISDB-T receiving device and receiving method>
The operation of ISDB-T receiving apparatus 3300 in FIG. 4 for a signal transmitted from transmitting apparatus 3600 in FIG. 9 is the same as the operation for a signal transmitted from transmitting apparatus 3000 in FIG. 1 in the first embodiment.

The signal transmitted from the transmitting device 3600 in FIG. 9 has TMCC also added by the LDM method, but the TMCC (LL signal) of the new broadcasting method has lower power than the TMCC (UL signal) of the ISDB-T method, ranging from 17.5 dB to 25 dB. Since the required C/N for TMCC of the current broadcasting by the ISDB-T method is about 10 dB, the TMCC (LL signal) of the new broadcasting method will be buried at a power level below the noise at a receiving point near the required C/N. This makes it possible to eliminate adverse effects on existing ISDB-T receiving devices. Note that the range of the UL/LL signal power ratio for TMCC is not limited to 17.5 dB to 25 dB, and may include values smaller than this range.

<Receiving device and receiving method>
Fig. 10 is a diagram showing the configuration of a receiving device 3800 in the second embodiment of the present invention. The receiving device 3800 in Fig. 10 corresponds to the transmitting device 3600 in Fig. 9, and reflects the functions of the transmitting device 3600. The same components as those in the existing ISDB-T receiving device and the receiving device in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

Compared to the receiving device 3500 in the first embodiment shown in FIG. 7, the receiving device 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.

The operation of the receiving device 3800 will be described below. The UL received TMCC signal reconstruction unit 3851 uses the transmission path estimation value and the UL TMCC decoded signal output from the TMCC signal decoding unit 3535 to reconstruct the received TMCC signal (FFT output before equalization) when transmitted only via UL.

The delay unit 3853 delays the pre-equalization FFT output output from the demodulation unit 3311 to align the timing with the output of the UL reception TMCC signal reconstruction unit 3851. The subtraction unit 3855 subtracts the output of the UL reception TMCC signal reconstruction unit 3851 from the output of the delay unit 3853, and outputs the result as the received TMCC signal (pre-equalization FFT output) when transmitted only by LL.

The TMCC signal decoding unit 3835 basically performs the same operation as the TMCC signal decoding unit 3535, but 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.

Other operations are the same as those of the receiving device 3500 in the first embodiment shown in FIG. 7. Note that the components of the receiving device 3800 in FIG. 10, excluding the tuner unit 3305, may be included to form an integrated circuit 3841.

With the above configuration, a receiving device compatible with the new broadcasting system can decode TMCC that has been added using the LDM system, and decode UL and LL signals.

(Embodiment 3)
<Transmitting device and transmitting method>
11 is a diagram showing the configuration of a transmission device 4000 according to the third embodiment of the present invention. The same components as those in the conventional transmission device and the transmission device according to the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

Compared to the transmitting device 3000 in the first embodiment shown in FIG. 1, the transmitting device 4000 in FIG. 11 has a configuration in which a pilot signal generating unit (for LL addition) 4081, a power difference control unit 3251, an adding unit 3261, and a power normalization unit 3271 are added.

In FIG. 11, pilot signal generator (for LL addition) 4081 generates a pilot signal for synchronous reproduction using a pseudo-random binary sequence different from that of pilot signal generator 5081. Power difference controller 3251, adder 3261, and power normalizer 3271 perform the same operations as in FIG. 2 on the outputs of pilot signal generator 5081 and pilot signal generator (for LL addition) 4081.

The frame configuration unit 5101 configures an ISDB-T 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.

Other operations are the same as those of the transmitting device 3000 in embodiment 1 shown in Figure 1.

With the above configuration, LDM method addition is also performed on pilot signals such as SP signals. As a result, existing ISDB-T receiving devices can observe the reception C/N of information data and pilot signals at the same level, so the reception C/N detection value using the pilot signal is at the same level as the reception C/N of information data, eliminating any adverse effects. On the other hand, for receiving devices compatible with the new broadcasting system, the pilot signal to which LDM method addition has been performed is already 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.

<Existing ISDB-T receiving device and receiving method>
The operation of ISDB-T receiving apparatus 3300 in FIG. 4 for a signal transmitted from transmitting apparatus 4000 in FIG. 11 is similar to the operation for a signal transmitted from transmitting apparatus 3000 in FIG. 1 in the first embodiment.

The signal transmitted from the transmitting device 4000 in FIG. 11 has pilot signals such as SP signals added using the LDM method, but since existing ISDB-T receiving devices can observe the received C/N of information data and pilot signals at the same level, the received C/N detection value using the pilot signal is at the same level as the received C/N of information data, eliminating any adverse effects.

<Receiving device and receiving method>
Fig. 12 is a diagram showing the configuration of a receiving device 4600 in the third embodiment of the present invention. The receiving device 4600 in Fig. 12 corresponds to the transmitting device 4000 in Fig. 11, and reflects the functions of the transmitting device 4000. The same components as those in the existing ISDB-T receiving device and the receiving devices in the first and tenth embodiments are given the same reference numerals, and the description thereof will be omitted.

Compared to the receiving device 3500 in FIG. 7 of embodiment 1, the receiving device 4600 has a configuration in which the demodulation unit 3311 is replaced with a demodulation unit 4611.

In the receiving device 4600 of FIG. 12, the demodulation unit 4611 performs OFDM demodulation on the SP signal 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 with a power difference.

Other operations are the same as those of the receiving device 3500 in the first embodiment shown in FIG. 7. Note that the components of the receiving device 4600 in FIG. 12, excluding the tuner unit 3305, may be included to form an integrated circuit 4641.

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

(Embodiment 4)
<Transmitting device and transmitting method>
13 is a diagram showing a configuration of a transmission device 4100 according to the fourth embodiment of the present invention. The same components as those in the conventional transmission device and the transmission devices according to the first to third embodiments are given the same reference numerals, and the description thereof will be omitted.

The transmitting device 4100 in FIG. 13 has a configuration in which the hierarchical processing unit 3041 is replaced with a hierarchical processing unit 4141 compared to the transmitting device 3000 in the first embodiment shown in FIG. 1.

Figure 14 shows the configuration of the hierarchical processing unit 4141. Compared to the hierarchical processing unit 3041 in the first embodiment shown in Figure 2, this configuration adds a selector 4145.

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. In other words, the output of the hierarchical processing unit 4141 is the same as the output in FIG. 2.

On the other hand, 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. In other words, the output of the hierarchical processing unit 4141 is a carrier modulation signal (LL) of the new broadcasting system, but the power cannot be reduced.

Figure 15 shows part of the definition of the TMCC signal. Figures 15(a) and (b) respectively show the definitions of B20 to B21 in the TMCC signal in the ISDB-T system and in this embodiment 4. 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 digital terrestrial television broadcasting system". Therefore, when B20 to B21 = "00", a selection signal "0" is input to the hierarchy processing unit 4141, and when B20 to B21 = "01", a selection signal "1" is input to the hierarchy processing unit 4141.

Other operations are the same as those of the transmitting device 3000 in embodiment 1 shown in Figure 1.

The above configuration allows the hierarchical processing unit to select either the LDM method by the transmitting device 3000 in embodiment 1 shown in Figure 1 or a signal that is only new broadcast (LL signal) by the new broadcast method. This makes it possible to build a system that anticipates that several years after the application method of the LDM method is put into practical use, the current broadcast (UL signal) by the ISDB-T method will be stopped and only new broadcast (LL signal) by the new broadcast method will be used.

<Existing ISDB-T receiving device and receiving method>
Regarding the operation of ISDB-T receiving apparatus 3300 in FIG. 4 for a signal transmitted from transmitting apparatus 4300 in FIG. 13, only the points different from the operation for a signal transmitted from transmitting apparatus 3000 in FIG. 1 in the first embodiment will be explained.

When B20 to B21 in the TMCC signal in the transmitting device 4300 in FIG. 13 = "10", the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 in FIG. 4 interprets the transmitted signal as undefined and determines that it cannot be received.

On the other hand, when B20 to B21 in the TMCC signal are "00" in the transmitting device 4300 in FIG. 13, the TMCC signal decoder 3335 in the ISDB-T receiving device 3300 in FIG. 4 interprets the transmitted signal as a terrestrial digital television broadcasting system (ISDB-T) and performs the same operation as in embodiment 1 to output a TS for each layer of the ISDB-T system that has been subjected to error correction decoding.

<Receiving device and receiving method>
Fig. 16 is a diagram showing the configuration of a receiving device 4700 in the fourth embodiment of the present invention. The receiving device 4700 in Fig. 16 corresponds to the transmitting device 4100 in Fig. 13, and reflects the functions of the transmitting device 4100. The same components as those in the existing ISDB-T receiving device and the receiving devices in the first to third embodiments are given the same reference numerals, and the description thereof will be omitted.

Compared to the receiving device 3500 in the first embodiment shown in FIG. 7, the receiving device 4700 has a configuration in which the TMCC signal decoding unit 3535 is replaced with a TMCC signal decoding unit 4735 and a selector 4145 is added.

The following describes the operation of the receiving device 4700 in the transmitting device 4300 in Figure 13 when B20 to B21 = "10" in the TMCC signal. 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.

The selector 4145 selects the output of the time deinterleaving unit 3321. In other words, the output of the selector 4145 is the mapping data of the I and Q coordinates and the transmission path estimation value after equalization of the carrier modulation signal (LL) of the new broadcasting system, but corresponds to the signal transmitted without reducing the power by the transmitting device 4100 in FIG. 13.

The FEC decoding unit 3533 performs the same operation as shown in FIG. 7 and outputs the TS for each layer of the new broadcasting method that has undergone error correction decoding.

Other operations are the same as those of the receiving device 3500 in the first embodiment shown in FIG. 7. Note that the components of the receiving device 4700 in FIG. 16, excluding the tuner unit 3305, may be included to form an integrated circuit 4741.

On the other hand, in the case of the transmitting device 4300 in FIG. 13, when B20 to B21 in the TMCC signal are "00", 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. The rest of the operation is the same as that of the receiving device 3500 in the first embodiment 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 broadcasting system.

With the above configuration, a receiving device compatible with the new broadcasting system can output TS (LL decoded signal) of each layer of the new broadcasting system even if the current broadcasting (UL signal) according to the ISDB-T system is stopped several years after the application method of the LDM system is put into practical use, and only new broadcasting (LL signal) according to the new broadcasting system is available. In particular, in this case, the signal transmitted by the transmitting device 4100 in Figure 13 is received without reducing the power, so the area in which the new broadcasting system can be viewed by the receiving device 4700 is expanded.

(Embodiment 5)
<Transmitting device and transmitting method>
17 is a diagram showing the configuration of a transmission device 4200 according to the fifth embodiment of the present invention. The same components as those in the conventional transmission device and the transmission devices according to the first to fourth embodiments are given the same reference numerals, and the description thereof will be omitted.

Compared to the transmitting device 4100 in the fourth embodiment shown in FIG. 13, the transmitting 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 generating unit 5081, the TMCC/AC signal generating unit 5091, the frame constructing unit 5101, and the OFDM signal generating unit 5111 are replaced with the hierarchical synthesis unit 4251, the time interleaving unit 4261, the frequency interleaving unit 4271, the pilot signal generating unit 4281, the TMCC/AC signal generating unit 4291, the frame constructing unit 4301, and the OFDM signal generating unit 4311, respectively. A selection signal is input to these processing units, and processing is switched based on whether the value is "0" or "1".

When the selection signal is "0", these processing units operate in the same manner as the transmitting device 4100 in the fourth embodiment shown in FIG. 3, with the FFT size and GI values corresponding to the same values as the ISDB-T system (FFT size: three types, 2k, 4k, 8k, GI: four types, 1/4, 1/8, 1/16, 1/32).

The operation of the transmitting device 4200 when the selection signal is "1" will be described below. In this case, only new broadcasts (LL signals) according to the new broadcasting system are received, and these processing units also operate to accommodate values different from 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).

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.

Figure 18 shows the segment configuration of this embodiment 5, taking the synchronous modulation section with an FFT size of 32k as an example when the selection signal is "1". As shown in Figure 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 Figure 18, when the FFT size is 32k, it is composed of 16 times as many, 1728 carriers. In Figure 18, the SP signal is arranged repeatedly with a period of 4 symbols as in Figure 26, and is arranged by shifting 3 carriers for each symbol. However, the arrangement pattern of the SP signal is not limited to this, and may be selected from multiple types. In addition, the carriers of the TMCC signal and the AC signal are arranged randomly in the frequency direction to reduce the influence of 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 when the FFT size is 2k, but the value is not limited to this. In this way, the pilot signal generator 4281 and the TMCC/AC signal generator 4291 respectively generate pilot signals for synchronous playback such as SP signals and TMCC/AC signals.

The frame configuration unit 4301 configures 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 the processing function for two types of FFT sizes: 16k and 32k.

The OFDM signal generation unit 4311 performs IFFT and inserts a 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 size, 16k and 32k, and two types of GI, 1/64 and 1/128.

Other operations are the same as those of the transmitting device 4100 in embodiment 4 shown in Figure 13.

With the above configuration, when it is possible to select either the LDM method by the transmitting device 3000 in embodiment 1 shown in Figure 1 or a signal only of new broadcast (LL signal) by the new broadcast method, it is possible to construct a method that anticipates the possibility that several years after the application method of the LDM method is put into practical use, the current broadcast (UL signal) by the ISDB-T method will be stopped and only new broadcast (LL signal) by the new broadcast method will be used. In particular, when only new broadcast (LL signal) by the new broadcast method is used, it will be possible to operate with FFT size and GI values that correspond to values different from those of the ISDB-T method.

<Existing ISDB-T receiving device and receiving method>
Regarding the operation of ISDB-T receiving apparatus 3300 in FIG. 4 for a signal transmitted from transmitting apparatus 4200 in FIG. 17, only the points that differ from the operation for a signal transmitted from transmitting apparatus 4100 in FIG. 13 in embodiment 4 will be explained.

In the transmitting device 4200 in FIG. 17, when B20 to B21 in the TMCC signal are "10", the ISDB-T receiving device 3300 cannot detect a signal transmitted with an FFT size that is different from that of the ISDB-T system (16k, 32k). The ISDB-T receiving device 3300 can decode a TMCC signal and determines that a signal cannot be received if the FFT size is the same as that of the ISDB-T system (2k, 4k, 8k), as in embodiment 4. In both cases, it determines that a signal cannot be received, but in the former case it does so because it is not possible to detect the signal, and in the latter case it does so based on the TMCC signal decoding result.

On the other hand, when B20 to B21 in the TMCC signal are "00" in the transmitting device 4300 in FIG. 13, the TMCC signal decoder 3335 in the ISDB-T receiving device 3300 in FIG. 4 interprets the transmitted signal as a terrestrial digital television broadcasting system (ISDB-T) and performs the same operation as in embodiment 1 to output a TS for each layer of the ISDB-T system that has been subjected to error correction decoding.

<Receiving device and receiving method>
Fig. 19 is a diagram showing the configuration of a receiving device 4800 in the fifth embodiment of the present invention. The receiving device 4800 in Fig. 19 corresponds to the transmitting device 4200 in Fig. 17, and reflects the functions of the transmitting device 4200. The same components as those in the existing ISDB-T receiving device and the receiving devices in the first to fourth embodiments are given the same reference numerals, and the description thereof will be omitted.

Compared to the receiving device 4700 in the fourth embodiment shown in FIG. 16, the receiving device 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 in the TMCC signal decoding unit 4835 and input to these processing units, and processing is switched based on whether the value is "0" or "1".

When the selection signal is "0", these processing units operate in the same manner as the receiving device 4700 in the fourth embodiment shown in FIG. 16, with the FFT size and GI values corresponding to the same values as the ISDB-T system (three types of FFT size: 2k, 4k, and 8k, and four types of GI: 1/4, 1/8, 1/16, and 1/32). Therefore, the receiving device 4800 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 broadcasting system.

On the other hand, when the selection signal is "1", and only new broadcasts (LL signals) are being received using the new broadcasting system, these processing units also operate in response to values different from the ISDB-T system (for example, five types of FFT size: 2k, 4k, 8k, 16k, and 32k, and six types of GI: 1/4, /8, 1/16, 1/32, 1/64, and 1/128).

When the selection signal is "1", the demodulation unit 4811 performs OFDM demodulation, but also has the processing function for two types of FFT size, 16k and 32k, and two types of GI, 1/64 and 1/128.

The TMCC signal decoding unit 4835 decodes the TMCC signal from the pre-equalized FFT output output from the demodulation unit 4811, and also has processing capabilities 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.

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

Other operations are the same as those of the receiving device 4700 in the fourth embodiment shown in FIG. 16, and output TS for each layer of the new broadcasting system that has undergone error correction decoding. Note that the components of the receiving device 4800 in FIG. 17, excluding the tuner unit 3305, may be included in an integrated circuit 4841.

With the above configuration, a receiving device compatible with the new broadcasting system will output TS (LL decoded signal) for each layer of the new broadcasting system even if the current broadcasting (UL signal) using the ISDB-T system is stopped several years after the application method of the LDM system is put into practical use, and only new broadcasting (LL signal) using the new broadcasting system is used. In particular, in this case, the transmitting device 4200 in FIG. 17 receives the signal transmitted without reducing the power, so the area in which the receiving device 4800 can view the new broadcasting system is expanded, and the receiving device 4800 can operate with FFT size and GI values that are different from those of the ISDB-T system.

(Embodiment 6)
<Transmitting device and transmitting method>
20 is a diagram showing the configuration of a transmission device 4400 according to the sixth embodiment of the present invention. The same components as those in the conventional transmission device and the transmission devices according to the first to fifth embodiments are given the same reference numerals, and the description thereof will be omitted.

Compared to the transmitting device 4100 in the fourth embodiment shown in FIG. 13, the transmitting device 4400 in FIG. 20 has a configuration in which a time interleaving unit 4461, a frequency interleaving unit 4471, a pilot signal generating unit 4481, a frame constructing unit 4501, a signaling generating unit 4541, a preamble generating unit 4551, and two selectors 4445-1 to 4445-2 have been added, and the OFDM signal generating unit 5111 has been replaced with an OFDM signal generating unit 4311. Depending on whether the value of the selection signal is "0" or "1", either the LDM method of the transmitting device 3000 in the first embodiment shown in FIG. 1 or a signal of only new broadcasting by the new broadcasting method is selected as the output of the transmitting device 4400.

When the selection signal is "0", the LDM transmission signal by the transmitting device 3000 in the first embodiment shown in FIG. 1 is selected and output from the transmitting device 4400. In this case, like the transmitting device 4100 in the fourth embodiment shown in FIG. 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).

The operation of the transmitting device 4400 when the selection signal is "1" will be described below. In this case, it also operates in response to values different from 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, multiple layers are not divided in the frequency direction using a segment structure, but are divided in the time direction using a structure that stores each layer in a subframe.

When the selection signal is "1", the time interleaving unit 4461 and the frequency interleaving unit 4471 perform interleaving using a subframe structure rather than interleaving using a segment structure. In addition, it also has processing capabilities for two types of FFT sizes: 16k and 32k.

Figure 21 shows the SP signal arrangement pattern of this embodiment 6 when the selection signal is "1". As shown in Figure 21, similar to Figures 18 and 78, the SP signal is arranged repeatedly with a period of 4 symbols, and is arranged by shifting 3 carriers for each symbol. However, the arrangement pattern of the SP signal is not limited to this, and a configuration in which a selection is made from multiple types is also possible. Also, no carriers are provided for the TMCC signal and the AC signal. In this way, the pilot signal generation unit 4481 generates pilot signals for synchronous reproduction of SP signals, etc.

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 a subframe.

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

The OFDM signal generator 4311 performs IFFT and inserts GI into 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 generator 4311 also has the processing function for two types of FFT size, 16k and 32k, and two types of GI, 1/64 and 1/128.

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.

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

Other operations are the same as those of the transmitting device 4100 in embodiment 4 shown in Figure 13.

With the above configuration, when it is possible to select either the LDM method by the transmitting device 3000 in embodiment 1 shown in Figure 1 or a signal only of new broadcast (LL signal) by the new broadcast method, it is possible to construct a method that anticipates the possibility that several years after the application method of the LDM method is put into practical use, the current broadcast (UL signal) by the ISDB-T method will be stopped and only new broadcast (LL signal) by the new broadcast method will be used. In particular, when only new broadcast (LL signal) by the new broadcast method is used, it will be possible to operate with FFT size and GI values that correspond to values different from those of the ISDB-T method, and it will also be possible to divide it in the time direction using a structure that stores each layer in a subframe.

<Existing ISDB-T receiving device and receiving method>
Regarding the operation of ISDB-T receiving apparatus 3300 in FIG. 4 for a signal transmitted from transmitting apparatus 4400 in FIG. 20, only the points that differ from the operation for a signal transmitted from transmitting apparatus 4100 in FIG. 13 in embodiment 4 will be explained.

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

On the other hand, when the selection signal is "0" in the transmitting device 4400 in FIG. 20, the TMCC signal decoding unit 3335 in the ISDB-T receiving device 3300 in FIG. 4 interprets the transmitted signal as a terrestrial digital television broadcasting system (ISDB-T) and performs the same operation as in embodiment 1 to output a TS for each layer of the ISDB-T system that has been subjected to error correction decoding.

<Receiving device and receiving method>
Fig. 22 is a diagram showing the configuration of a receiving device 4900 in the sixth embodiment of the present invention. The receiving device 4900 in Fig. 22 corresponds to the transmitting device 4400 in Fig. 20, and reflects the functions of the transmitting device 4400. The same components as those in the existing ISDB-T receiving device and the receiving devices in the first to fifth embodiments are given the same reference numerals, and the description thereof will be omitted.

Compared to the receiving device 3500 in the first embodiment shown in FIG. 7, the receiving device 4900 has a configuration in which a frequency deinterleaving unit 4915, a time deinterleaving unit 4921, a preamble detection unit 4961, and a selector 4945 are added, and the demodulation unit 3311 is replaced with a demodulation unit 4811.

When the selection signal is "0" in transmitting device 4400 in Fig. 20, receiving device 4900 in Fig. 22 operates in the same manner as receiving device 3500 in embodiment 1 shown in Fig. 7, and outputs TS (UL decoded signal) of each layer of the ISDB-T system and TS (LL decoded signal) of each layer of the new broadcasting system. Note that receiving device 4900 operates in response to the same FFT size and GI values as the ISDB-T system (three types of FFT size: 2k, 4k, 8k, and four types of GI: 1/4, 1/8, 1/16, 1/32).

On the other hand, the operation of the receiving device 4900 when the selection signal is "1" in the transmitting device 4400 in FIG. 20 will be described below.

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

The demodulation unit 4811 performs OFDM demodulation, but also has the processing function for two types of FFT size, 16k and 32k, and two types of GI, 1/64 and 1/128.

The frequency deinterleaving unit 4915 and the time deinterleaving unit 4921 perform deinterleaving using a subframe structure on the output of the demodulation unit 4811.

The selector 4945 selects and outputs the output of the time deinterleaving unit 4921.

Other operations are the same as those of the receiving device 3500 in the first embodiment shown in FIG. 7, and the TS of each layer of the new broadcasting method that has undergone error correction decoding is output. Note that the components of the receiving device 4900 in FIG. 22, excluding the tuner unit 3305, may be included in an integrated circuit 4941.

With the above configuration, a receiving device compatible with the new broadcasting system will output TS (LL decoded signal) of each layer of the new broadcasting system even if the current broadcasting (UL signal) according to the ISDB-T system is stopped several years after the application method of the LDM system is put into practical use, and only new broadcasting (LL signal) according to the new broadcasting system is available. In particular, in this case, the transmitting device 4400 in FIG. 20 receives the signal transmitted without reducing the power, so the receiving device 4900 can expand the viewing area of the new broadcasting system, and the receiving device 4900 can operate with FFT size and GI values different from those of the ISDB-T system. Furthermore, in this case, the receiving device 4900 can operate in response to a transmission signal divided in the time direction using a structure that stores each layer in a subframe.

(supplement)
The present disclosure is not limited to the contents described in the above embodiments 1 to 6, and may be implemented in any form for achieving the object of the present disclosure and related or incidental objects, for example, as follows.

(1) In the first to sixth embodiments, the input to the transmitting device for the new broadcasting system is a TS, but this is not limited to this. For example, IP packets, MMT (MPEG Media Transport), or packets encapsulating these may also be used.

(2) In the first to fifth embodiments, the definition of B110 to B121 in the TMCC signal is as shown in FIG. 3, but is not limited to this. The UL/LL signal power ratio, the carrier modulation mapping method of each layer LL signal, and the LDPC coding rate of each layer LL signal may be different from those shown in FIG. 3.

(3) In the fourth to sixth embodiments, the values different from the ISDB-T system are 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. However, these are merely examples and are not limiting.

(4) In the first to sixth embodiments, the addition in the LDM method is performed immediately after the mapping unit, but this is not limited to the above. The addition in the LDM method can be performed between the mapping unit and the OFDM signal generation unit.

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

(6) The above embodiments 1 to 6 may relate to implementations 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 application specific integrated circuit (ASIC), a field programmable gate array (FPGA), other programmable logic devices, etc. The above embodiments may be executed or realized by a combination of these devices.

(7) The first to sixth embodiments may be realized by a mechanism of software modules executed by a processor or directly by hardware. A combination of software modules and hardware implementation 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.

The transmitting device, transmitting method, receiving device, receiving method, integrated circuit, and program disclosed herein can be applied to wireless transmission methods.

3000, 3600, 4000, 4100, 4200, 4400, 5000 transmitter 3500, 3800, 4600, 4700, 4800, 4900 receiver 3341, 3541, 3841, 4641, 4741, 4841, 4941 integrated circuit 3300 ISDB-T receiver 5011 TS remultiplexing section 5021 RS encoding section 5031 layer division section 3041, 4141, 5041 layer processing section 4251, 5051 layer synthesis section 4261, 4461, 5061 time interleaving section 3321, 4821, 4921 time deinterleaving section 4271, 4471, 5071 frequency interleaving section 3315, 4815, 4915 Frequency deinterleaving unit 3081, 4281, 4481, 5081 Pilot signal generating unit 4081 Pilot signal generating unit (for LL addition)
4291, 5091 TMCC/AC signal generation section 3691 TMCC/AC signal generation section (for LL)
4301, 4501, 5101 Frame configuration unit 4311, 5111 OFDM signal generation unit 5121 D/A conversion unit 5131 Frequency conversion unit 3201, 5201 Energy diffusion unit 3461, 3569 Energy de-diffusion unit 5211 Byte interleaving unit 3451 Byte de-interleaving unit 5221 Convolutional coding unit 3231, 5231 Bit interleaving unit 3411, 3563, 3911 Bit de-interleaving unit 3241, 5241 Mapping unit 3401, 3561 De-mapping unit 3211 BCH coding unit 3567 BCH decoding unit 3221 LDPC coding 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 interleave unit 5321 Intra-segment carrier rotation unit 5331 Intra-segment carrier randomization unit

Claims (7)

a Transmission Multiplexing Configuration Control (TMCC) signal generating unit that generates a parameter for identifying a broadcasting system, the parameter being included in a TMCC signal;
A transmitter that transmits a signal to be broadcast and the TMCC signal,
When the TMCC signal generating unit sets a first value indicating a first broadcasting system to the parameter, the transmitting unit transmits a signal generated in a Layered Division Multiplexing (LDM) format in which a signal of the first broadcasting system is an Upper Level (UL) signal and a signal of a second broadcasting system that is standardized after the standardization of the first broadcasting system is a Lower Level (LL) signal;
When the TMCC signal generating unit sets the parameter to a second value indicating the second broadcasting system, the transmitting unit transmits only a signal of the second broadcasting system.
Transmitting device. the transmitting unit generates the LL signal by reducing power of a signal of the second broadcasting system when the first value is set to the parameter;
When the second value is set to the parameter, the transmission unit transmits the signal of the second broadcasting system without reducing power.
2. The transmitting device according to claim 1. a receiving unit for receiving a broadcast signal and a Transmission Multiplexing Configuration Control (TMCC) signal;
a TMCC signal decoding unit that decodes the TMCC signal,
The TMCC signal is provided with a parameter for identifying a broadcasting system,
When a first value indicating a first broadcasting system is set in the parameter, the receiving unit performs Layered Division Multiplex (LDM) signal transmission in which a signal of the first broadcasting system is an Upper Level (UL) signal and a signal of a second broadcasting system that is standardized after the standardization of the first broadcasting system is a Lower Level (LL) signal.
Receive a signal generated by the LDM (Light Detection and Messaging) method,
When a second value indicating the second broadcasting system is set in the parameter, the receiving unit receives only a signal of the second broadcasting system.
Receiving device. When the first value is set to the parameter,
receiving the LL signal generated by reducing the power of a signal of the second broadcasting system;
When the second value is set to the parameter,
receiving the signal of the second broadcasting system transmitted without reducing the power of the signal of the second broadcasting system;
4. The receiving device according to claim 3. a TMCC signal decoding unit that outputs a Transmission Multiplexing Configuration Control (TMCC) signal by decoding a received signal;
a decoding unit that outputs a signal of a second broadcasting system by decoding the received signal when a second value indicating a second broadcasting system that is standardized after the standardization of the first broadcasting system is set in a parameter for identifying a broadcasting system and that is provided in the TMCC signal;
The decoding unit is
When a first value is set to the parameter, it is determined that a signal generated in a Layered Division Multiplexing (LDM) format in which a signal of the first broadcasting system is an Upper Level (UL) signal and a signal of a second broadcasting system that is standardized after the standardization of the first broadcasting system is a Lower Level (LL) signal is transmitted as the received signal .
Receiving device. When the second value is set to the parameter, the decoding unit generates a signal of the second broadcasting system without performing subtraction processing on the UL signal.
6. The receiving device according to claim 5. Decoding the received signal to output a Transmission Multiplexing Configuration Control (TMCC) signal;
When a second value indicating a second broadcasting system that is standardized after the standardization of the first broadcasting system is set in a parameter for identifying a broadcasting system and that is provided in the TMCC signal, the received signal is decoded to output a signal of the second broadcasting system;
When a first value is set to the parameter, it is determined that a signal generated in a Layered Division Multiplexing (LDM) format in which a signal of the first broadcasting system is an Upper Level (UL) signal and a signal of a second broadcasting system that is standardized after the standardization of the first broadcasting system is a Lower Level (LL) signal is transmitted as the received signal .
Make the computer do something
program.

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