Transmitting device, receiving device, and relay station

Abstract

To provide a transmitter, a receiver, and relay stations, capable of transmitting or receiving TxIDs, which are allocated to the respective relay stations, in a multiplexed manner in a broadcasting system using FDM.SOLUTION: In a broadcasting system for transmitting a broadcast signal using an FDM modulation system, a transmitter 101 or a relay station 300 multiplexes and transmits identification information for identifying the transmitter or the relay station on an FDM subcarrier on a frequency axis of the broadcast signal.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a transmitting device, a receiving device, and a relay station. [Background technology]

[0002] To improve the quality and functionality of terrestrial digital broadcasting, studies are underway on a next-generation terrestrial broadcasting transmission system (advanced terrestrial broadcasting system) that inherits the features of the current ISDB-T system (Non-Patent Document 1). ISDB-T is an abbreviation for Integrated Services Digital Broadcasting - Terrestrial. It is envisioned that the advanced terrestrial broadcasting system will also build a broadcasting network equivalent to that of the current terrestrial broadcasting system.

[0003] In Japan's current terrestrial broadcasting, a broadcasting network has been constructed using the Orthogonal Frequency Division Multiplexing (OFDM) modulation method, which enables the construction of a Single Frequency Network (SFN) in which radio waves are emitted at a single frequency from a master station and relay stations (Non-Patent Document 2). SFN is an abbreviation for Single Frequency Network. OFDM is an abbreviation for Orthogonal Frequency Division Multiplexing. In an SFN, the same channel and content are transmitted in multiple areas, enabling efficient use of frequencies. For the advanced terrestrial broadcasting system, the construction of a broadcasting network using the OFDM modulation method, which enables the construction of such an SFN, is also being considered. In addition, in ISDB-T, layers for fixed reception and mobile reception are multiplexed using Frequency Division Multiplexing (FDM). FDM is an abbreviation for Frequency Division Multiplexing.

[0004] On the other hand, ATSC3.0, the North American terrestrial broadcasting transmission standard, uses signal multiplexing by time division multiplexing (TDM). ATSC is an abbreviation for Advanced Television Systems Committee. TDM is an abbreviation for Time Division Multiplexing. In the ATSC3.0 system, a transmitting station can multiplex a TxID onto a preamble signal of a transmission signal and transmit it (Non-Patent Document 3). A TxID is an identification ID assigned individually to each relay station. By receiving a signal with a TxID, the receiving side can determine which relay station the signal is from. Therefore, by demodulating the TxID, a receiving point in the network can determine the delay with which radio waves from each relay station arrive. Note that in ATSC3.0, TxID multiplexing is optional, and whether or not to multiplex is decided by the broadcaster. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] NHK R&D, No.172, P.2~P.47, November 2018 [Non-patent document 2] ARIB STD-B31 Association of Radio Industries and Businesses [Non-patent document 3] ATSC 3.0 Standard: Physical Layer Protocol A / 322:2020 P245-249, Internet〈https: / / www.atsc.org / wp-content / uploads / 2020 / 01 / A322-2020-Physical-Layer-Protocol.pdf〉 Summary of the Invention [Problem to be solved by the invention]

[0006] When relay stations are installed in an SFN, they are designed so that the arrival time difference between two stations in the reception area falls within the OFDM guard interval. In an SFN area where radio waves from two relay stations arrive, the receiver can determine that two waves are arriving by acquiring a delay profile. However, the receiver cannot determine which wave is the main wave, or, if there are multipath components, which relay station the multipath is from. Therefore, even in the advanced terrestrial broadcasting system, it is possible to multiplex and transmit a TxID assigned to each relay station, allowing the receiver to identify the signal source.

[0007] However, ATSC3.0 uses TDM, while FDM transmission is being considered for the Advanced Terrestrial Broadcasting Standards, and the signal structures of the two are different. That is, ATSC3.0 uses TDM and multiplexes the TxID into the preamble, while the Advanced Terrestrial Broadcasting Standards, which use FDM, do not have a preamble. Therefore, the ATSC3.0 method cannot be applied directly to the Advanced Terrestrial Broadcasting Standards.

[0008] An object of the present disclosure is to provide a transmitting device, a receiving device, and a relay station that are capable of multiplexing and transmitting or receiving TxIDs assigned to each relay station in a broadcasting system using FDM. [Means for solving the problem]

[0009] A transmitting device according to one aspect of the present disclosure, in a broadcasting system that transmits broadcast signals using an FDM modulation method, multiplexes identification information for identifying the transmitting device onto FDM subcarriers on the frequency axis of the broadcast signals and transmits the multiplexed information.

[0010] In one embodiment, the transmitting device multiplexes the identification information with control data relating to a transmission method of the broadcast signal and transmits the same.

[0011] In one embodiment, the transmitting device multiplexes the identification information into a plurality of symbols starting from the first symbol of the control data and transmits the multiplexed identification information.

[0012] In one embodiment, the transmitting device multiplexes the identification information onto at least one of an LLch and a TMCC carrier, which are known signals, as the control data and transmits the same.

[0013] In one embodiment, the transmitting device multiplexes the identification information onto L0ch or L1ch, which is a known signal, as the control data and transmits the same.

[0014] In one embodiment, the transmitting device multiplexes the identification information onto the FDM subcarriers on the frequency axis of the broadcast signal and transmits the multiplexed information a number of times corresponding to the number of FFT samples used in modulation / demodulation processing.

[0015] A transmitting device according to one aspect of the present disclosure, in a broadcasting system that transmits broadcast signals using an FDM modulation method, multiplexes identification information for identifying the device itself onto FDM subcarriers on the time axis of the broadcast signals and transmits the multiplexed information.

[0016] In one embodiment, the transmitting device multiplexes the identification information onto FDM subcarriers on the time axis of the broadcast signal and transmits the identification information so that the bandwidth for transmitting the identification information is equal to or smaller than the partial reception bandwidth.

[0017] In one embodiment, the receiving device receives the broadcast signal from the transmitting device, and analyzes the received broadcast signal to obtain the identification information.

[0018] In one embodiment, the relay station receives the broadcast signal from the transmitting device, removes noise from the received broadcast signal, assigns identification information that identifies the relay station to the noise-removed broadcast signal, and transmits the broadcast signal with the identification information assigned. [Effects of the Invention]

[0019] According to one embodiment of the present disclosure, in a broadcasting system using FDM, it is possible to provide a transmitting device, a receiving device, and a relay station that are capable of multiplexing and transmitting or receiving TxIDs assigned to each relay station. [Brief explanation of the drawings]

[0020] [Figure 1A] FIG. 2 is a diagram illustrating a configuration example of a modulator of a transmission device according to an embodiment of the present disclosure. [Figure 1B] FIG. 2 is a diagram illustrating an example of the configuration of a BICM unit. [Figure 2] FIG. 10 is a diagram illustrating a process of assigning a TxID to each OFDM frame. [Figure 3] FIG. 2 is a diagram illustrating a configuration example of a TxID generation unit according to an embodiment of the present disclosure. [Figure 4] FIG. 1 is a diagram illustrating a configuration example of a receiving device according to an embodiment of the present disclosure. [Figure 5A] FIG. 2 is a diagram illustrating an example of a waveform of a received signal. [Figure 5B] FIG. 10 is a schematic diagram showing an example of the correlation between a received signal and a TxID. [Figure 6] FIG. 10 is a diagram illustrating a configuration example of a relay station according to an embodiment of the present disclosure. [Figure 7] FIG. 2 is a diagram illustrating a configuration example of a modulator of a transmission device according to an embodiment of the present disclosure. [Figure 8] FIG. 2 is a diagram illustrating a configuration example of a TxID generation unit according to an embodiment of the present disclosure. [Figure 9A] FIG. 10 is a diagram illustrating an example of the number of LLch carriers in one symbol. [Figure 9B] FIG. 10 is a diagram illustrating an example of the number of LLch carriers in one symbol. [Figure 10] FIG. 1 is a diagram illustrating a configuration example of a receiving device according to an embodiment of the present disclosure. [Figure 11] FIG. 10 is a diagram illustrating a configuration example of a relay station according to an embodiment of the present disclosure. [Figure 12] FIG. 2 is a diagram illustrating a configuration example of a TxID generation unit according to an embodiment of the present disclosure. [Figure 13]FIG. 1 is a diagram illustrating a configuration example of a receiving device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals. In the description of this embodiment, the description of the same or corresponding parts will be omitted or simplified as appropriate.

[0022] First Embodiment (Transmitting device) 1A is a block diagram showing an example configuration of a modulator of a transmitting device 100 according to a first embodiment of the present disclosure. The block diagram of the modulator of the transmitting device 100 in FIG. 1A shows from a data input interface to an IF signal output. The transmitting device 100 multiplexes a TxID onto an OFDM signal on the time axis, thereby enabling multiplexing and transmission or reception of TxIDs assigned to each relay station.

[0023] The modulator of the transmitting device 100 includes an input I / F (Interface) 10, a Bit-Interleaved Coded Modulation (BICM) unit 11, a level adjustment unit 14, a system separation unit 15, a hierarchical synthesis unit 16, a band division unit 17, a time interleave (IL) unit 18, a frequency interleave (IL) unit 19, a band synthesis unit 20, a multi-input single-output (MISO) coding unit 21, a transmission and multiplexing configuration control (TMCC) information bit generation unit 22, a synchronization bit generation unit 23, a TMCC generation unit 24, a pilot generation unit 25, an OFDM frame construction unit 26, an inverse fast fourier transform (IFFT) unit 27, a guard interval (GI) addition unit 28, a TxID generation unit 40a, and an attenuator 41a. Signal output 1 and IF signal output 2, which are outputs of the modulator, undergo predetermined modulation processing and are then output from different transmission systems (antennas). When the transmitting device 100 is realized by, for example, an FPGA (Field-Programmable Gate Array), each block of the transmitting device 100 operates on a common clock, so that signals can be synchronized between the blocks.

[0024] The input I / F (interface) 10 is an interface into which data to be transmitted is input, and various data such as data to be used as an image signal and control data related to a transmission method are input. For example, the data to be used as an image signal is divided into three layers, layer A, layer B, and layer C, as necessary, and output to the processing system of each layer. Furthermore, the control data is output as, for example, TMCC information or LLch (Low Latency Channel) data.

[0025] The BICM (Bit-Interleaved Coded Modulation) units 11 (11a, 11b, 11c) perform error correction coding and mapping to carrier symbols on the data sequences of layers A, B, and C. FIG. 1B shows the configuration of the BICM unit 11. The BICM unit 11 includes an energy dispersal unit 31, a BCH encoding unit 32, an LDPC encoding unit 33, and a mapping unit 34. The energy dispersal unit 31 converts data using a predetermined generator polynomial and performs signal processing to prevent specific frequency components of the modulated signal from increasing by reducing consecutive "0"s or "1"s. The BCH (Bose-Chaudhuri-Hocquenghem) encoding unit 32 performs BCH encoding on the data sequences of each layer that have been energy dispersed. The LDPC (Low-Density Parity-Check) encoding unit 33 performs LDPC encoding on the data sequences of each layer that have been BCH encoded. The mapping unit 34 maps the data onto the IQ plane for each predetermined number of bits based on the modulation method of each layer of data, and performs carrier conversion. That is, the mapping unit 34 converts the data into carrier symbols. The generated carrier symbols are output to the level adjustment unit 14.

[0026] 1A, the level adjustment units 14 (14a, 14b, 14c) adjust the levels of the carrier symbols for each layer. The adjusted carrier symbols are output to the demultiplexing unit 15.

[0027] The system separation unit 15 (15a, 15b, 15c) is a demultiplexer that separates input carrier symbols into multiple systems (two systems in this example). This system separation unit 15 operates only when the transmission method for that layer is a spatial division multiplexing MIMO (Multi-Input Multi-Output) transmission method. One of the separated carrier symbols for each layer is output to a layer combiner 161 for a first system (hereinafter simply referred to as "system 1"), and the other is output to a layer combiner 162 for a second system (hereinafter simply referred to as "system 2"). When the transmission method for that layer is the MISO method, the system separation unit 15 outputs all carrier symbols to the layer combiner 161 for system 1. When the MIMO transmission method is performed using three or more transmission systems, data is separated according to the number of transmission systems.

[0028] The layer combining unit 16 (161, 162) combines the carrier symbols of layers A, B, and C input from the system separating units 15a, 15b, and 15c, respectively. The layer combined carrier symbols are output to the band dividing unit 17 for each system.

[0029] The band dividing unit 17 (171, 172) divides the hierarchically combined carrier symbols into each band. For example, it divides a part of the C layer data into adjustment bands as necessary. The band-divided carrier symbols are output to the time IL unit 18.

[0030] The time IL (interleave) units 18 (181, 182) perform interleaving on the band-divided carrier symbols in the time direction (i.e., the direction in which the symbols are arranged in each carrier). The time-interleaved carrier symbols are output to the frequency IL unit 19.

[0031] The frequency IL (interleave) unit 19 (191, 192) performs interleaving in the carrier frequency direction. The frequency-interleaved carrier symbols are output to the band synthesis unit 20.

[0032] The band synthesis unit 20 (201, 202) synthesizes the carrier symbols of the frequency-interleaved partial reception band, non-partial reception band, and adjustment band to form a data segment. When the space division multiplexing MIMO system is adopted, the band synthesis unit 201 for the first system outputs a first system carrier symbol x1, and the band synthesis unit 202 for the second system outputs a second system carrier symbol x2 that is different from the first system.

[0033] The MISO encoding unit 21 performs space-time encoding (STBC (Space Time Block Code) encoding or SFBC (Space Frequency Block Code) encoding) on the data of the 1-system carrier symbol x1 to generate the 2-system carrier symbol x2. Note that in STBC encoding (hereinafter sometimes simply referred to as "STBC"), two data symbols are paired in the time direction, and the complex conjugate and sign inversion of the data carrier symbol is performed. In SFBC encoding (hereinafter sometimes simply referred to as "SFBC"), two data symbols are paired in the frequency direction, and the complex conjugate and sign inversion of the data carrier symbol is performed.

[0034] Based on the transmission method of each layer or each segment, a switch (selector) selects data and outputs it as 2-system carrier symbol x2. In the case of the MIMO method, the output from the 2-system band combiner 202 is output as 2-system carrier symbol x2, and in the case of the MISO method, the output from the MISO encoder 21 is output as 2-system carrier symbol x2. This switching is linked to the processing of the system separator 15. These carrier symbols x1 and x2 are output to the OFDM frame constructor 26.

[0035] A TMCC information (Transmission and Multiplexing Configuration Control Information) bit generator 22 receives TMCC information (various control information) from the input I / F 10, generates TMCC information bits, and outputs the TMCC information bits to a TMCC generator 24.

[0036] The synchronization bit generator 23 generates a synchronization bit that becomes part of the TMCC and outputs it to the TMCC generator 24.

[0037] The TMCC generation unit 24 receives the TMCC information bits from the TMCC information bit generation unit 22, the synchronization bits from the synchronization bit generation unit 23, and FEC (Forward Error Correction) pointer information, and generates a TMCC. The generated TMCC is output to the OFDM frame configuration unit 26.

[0038] The pilot generation unit 25 generates pilot signals (such as SP (Scattered Pilot) signals and CP (Continual Pilot) signals) to be incorporated into the OFDM frame. The generated pilot signals are output to the OFDM frame configuration unit .

[0039] The OFDM frame constructing units 26 (261, 262) construct an OFDM frame by adding a TMCC, a pilot signal, and an LLch signal to the input carrier symbol (data segment). The OFDM frame constructing unit 261 for system 1 generates an OFDM frame for system 1 based on the carrier symbol x1 for system 1, and the OFDM frame constructing unit 262 for system 2 generates an OFDM frame for system 2 based on the carrier symbol x2 for system 2. The generated OFDM frames are each output to the IFFT unit 27.

[0040] The IFFT units 27 (271, 272) perform IFFT (inverse fast Fourier transform) processing on the input OFDM frame to generate an effective symbol signal. The generated effective symbol signal is output to the GI adding unit .

[0041] The GI adding unit 28 (281, 282) adds a guard interval, which is a signal obtained by copying a portion of the end of the effective symbol signal, to the beginning of the effective symbol signal input from the IFFT unit 27. The guard interval is set so that the delay time of the multipath delay wave does not exceed the guard interval length. The signal of the first system to which the guard interval has been added has a TxID added in an adder 42a and is output as signal output 1. The signal of the second system to which the guard interval has been added is output as signal output 2. In this embodiment, the OFDM frame constructing unit 26, the IFFT unit 27, and the GI adding unit 28 may be collectively referred to as an "OFDM modulation unit."

[0042] In this embodiment, the adder 42a multiplexes the TxID output from the attenuator 41a onto the OFDM symbols of the main system (OFDM symbols including data carriers) for each OFDM frame. FIG. 2 is a diagram schematically illustrating the process of assigning a TxID to each OFDM frame. As shown in FIG. 2, the adder 42a assigns a TxID to the first few symbols of each OFDM frame. While FIG. 2 illustrates an example in which a TxID is assigned once for each OFDM frame, the number of times the TxID is assigned is not limited to this. Generally, when multiplexing is performed over the first few symbols, the greater the number of symbols, the greater the impact of degradation of the reception characteristics of the main system. Therefore, for example, the adder 42a may assign a TxID every few frames rather than every frame. In this case, although it takes longer to detect the TxID, it is possible to reduce the impact on the main system. Alternatively, depending on the application or purpose, the adder 42a may assign a TxID multiple times to one OFDM frame. In this case, the receiving side can receive the TxID signal multiple times in a short period of time, thereby improving the accuracy of detecting the TxID itself. Because the TxID is usually received as a low-level signal, the receiving side adds and averages multiple signals to improve the accuracy of detecting the TxID. Therefore, by transmitting and receiving the TxID multiple times in a short period of time, the receiving side can detect the TxID with high accuracy in a short period of time. Even when the communication characteristics of the transmission path fluctuate gradually over time, attaching the TxID multiple times enables more accurate TxID detection than the configuration in which the TxID is transmitted once per OFDM frame as shown in FIG. 2. Furthermore, by setting the interleave time IL long, the effect of TxID attachment on the main line signal degradation can be mitigated. In this way, the transmitting device 100 attaches a TxID to the OFDM signal on the time axis to identify itself. As will be described later, the relay station 300 also attaches a TxID to the OFDM signal on the time axis to identify itself. Therefore, the receiving side can identify the transmitting device 100 or relay station 300 that transmitted the received signal.Therefore, the receiving side can determine the delay time of the signal for each transmitting device 100 or relay station 300.

[0043] Returning to the explanation of FIG. 1A, the TxID generation unit 40a generates a TxID, which is identification information for identifying its own device (the transmitting device 100 in the example of FIG. 1A). FIG. 3 is a diagram showing an example of the configuration of the TxID generation unit 40a. The TxID generation unit 40a generates a TxID based on a Gold sequence, but may use a code other than the Gold sequence that has excellent autocorrelation and cross-correlation values. As shown in FIG. 3, the TxID generation unit 40a generates a TxID based on a Gold sequence. 1 ~x 13 Therefore, the TxID generator 40a assigns a TxID to a maximum of 8192 (=2 13 ) transmitters 100 or relay stations 300, each of which can be assigned a unique TxID. The period of the Gold sequence is 8191, and the generated 8191 sequence is BPSK (Binary Phase Shift Keying) modulated and output to the attenuator 41a. The example in FIG. 3 shows a case where the initial value is 13 bits, i.e., a case where a 13th-order atomic polynomial is used, but the Gold sequence may also be generated using an atomic polynomial of a higher order. This increases the number of TxIDs that can be assigned.

[0044] The clock rate of the TxID can be the same as that of the main line system (6.32 (512 / 81) MHz for the terrestrial broadcasting advanced standard). In this case, if band-limiting is performed using an ideal filter (roll-off rate α = 9), the bandwidth will be 3.16 MHz. Alternatively, band-limiting can be performed by reducing the clock rate of only the TxID so that the bandwidth is equal to or less than the partial reception bandwidth (1.5 MHz). This can reduce the impact on the main line system caused by assigning the TxID.

[0045] Returning to the explanation of FIG. 1A, the attenuator 41a attenuates the signal level (signal power) of the TxID signal output from the TxID generation unit 40a. Since the TxID signal acts as an interference component for the main line signal, it is sufficiently attenuated before multiplexing. The attenuator 41a can attenuate the TxID signal to a sufficiently low level, such as 20 dB (1 / 100) compared to the signal power of the main line signal. This makes it possible to mitigate the effect of degradation of the main line signal due to the assignment of the TxID. The TxID signal attenuated by the attenuator 41a is output to the adder 42a.

[0046] Signal outputs 1 and 2 undergo predetermined modulation processing and are then output from different antennas (transmission systems).

[0047] The modulator of the transmitting device 100 according to the first embodiment is configured as described above. The transmitting device 100 according to this embodiment multiplexes an ID (TxID) unique to the transmitting station onto the OFDM signal on the time axis. Therefore, according to the configuration of this embodiment, in a digital broadcasting system using FDM, it is possible to multiplex and transmit a TxID for identifying the device itself. Furthermore, as will be described later, the relay station 300 also multiplexes an ID (TxID) of its own device (unique to the transmitting station) onto the OFDM signal on the time axis. Therefore, even when signal waves from a plurality of transmitting devices 100 or relay stations 300 are mixed, the receiving side can distinguish the arrival times of each signal wave from the transmitting device 100 and the relay station 300 by correlating with the TxID.

[0048] (receiving device) 4 is a block diagram showing an example configuration of a receiving device 200 according to the first embodiment of the present disclosure. The receiving device 200 includes a receiving unit 51, a correlation calculation unit 52, and a TxID generation unit 53. The receiving unit 51 receives a signal transmitted by the transmitting device 100. The received signal received by the receiving unit 51 is output to the correlation calculation unit 52. The TxID generation unit 53 has a configuration similar to that of the TxID generation unit 40a included in the transmitting device 100, and generates a TxID. The generated TxID signal is output to the correlation calculation unit 52. The correlation calculation unit 52 correlates the received signal received by the receiving unit 51 with the TxID generated by the TxID generation unit 53, and identifies the TxID of the received signal received by the receiving unit 51.

[0049] FIG. 5A shows the delay profile of a received signal. The delay profile can be obtained by performing an inverse Fourier transform (IFFT) on the transfer function of the frequency characteristics, and indicates the level and delay of a delayed wave relative to the main wave. The horizontal axis represents time, and the vertical axis represents level. Although the delay profile (transmission delay characteristic) can be determined from the waveform of the delay profile, it is not possible to determine from the delay profile alone which transmitting device 100 or relay station 300 a radio wave was transmitted from. Therefore, the correlation calculation unit 52 of the receiving device 200 calculates the correlation between the received signal and the unique TxID generated by the TxID generation unit 53, and calculates the magnitude of the correlation and the position of the peak for each TxID. That is, the TxID generation unit 53 sequentially generates 8,192 different TxIDs, and the correlation calculation unit 52 calculates the correlation coefficient between the signal of each TxID generated by the TxID generation unit 53 and the received signal. The correlation calculation unit 52 identifies the signal of a TxID whose calculated correlation coefficient exceeds a predetermined value as the TxID of the received signal. This makes it possible to identify the TxID of the received signal and identify the transmitting device 100 or relay station 300 that transmitted the received signal.

[0050] FIG. 5B is a schematic diagram showing an example of the correlation between a received signal and a TxID. In FIG. 5B, the horizontal axis represents time, and the vertical axis represents the value of the correlation coefficient between the received signal and the unique TxID generated by the TxID generation unit 53. FIG. 5B also shows a schematic example of a correlation coefficient calculated for a received signal containing a mixture of signals from two transmitting devices 100 or relay stations 300. The first received signal exhibits a high correlation with Tx#1, which is the first TxID, and the second received signal exhibits a high correlation with Tx#2, which is the second TxID. Therefore, it can be seen that the first received signal is a signal transmitted from the transmitting device 100 or relay station 300 identified by Tx#1, and the second received signal is a signal transmitted from the transmitting device 100 or relay station 300 identified by Tx#2.

[0051] For example, if the FFT size is 8192 and the effective symbol length is 1296 μs, changing the number of samples to be moved from 0 to 800 corresponds to a delay of about 0 to 126 μs. Therefore, the FFT sample clock is 8192 / 1296 = 6.32 MHz, and the time required to calculate the correlation of 800 samples is 800 / 6.32 = 126.56 μs.

[0052] (Relay station) 6 is a diagram illustrating an exemplary configuration of a relay station 300 according to an embodiment of the present disclosure. The relay station 300 includes a receiving unit 61, an FFT (Fast Fourier Transform) unit 62, a channel estimating unit 63, an equalization and symbol determining unit 64, an IFFT unit 65, a GI adding unit 66, a TxID generating unit 67, an attenuator 68, and an adder 69.

[0053] The receiving unit 61 receives a signal transmitted by the transmitting device 100 or another relay station 300. The signal received by the receiving unit 61 is output to the FFT unit 62.

[0054] The FFT unit 62 performs FFT (Fast Fourier Transform) processing on the signal input from the receiving unit 61. The FFT-transformed received signal becomes a frequency-domain OFDM signal. The FFT-transformed received signal is output to a transmission path estimation unit 63 and an equalization / symbol decision unit 64.

[0055] The transmission path estimation unit 63 estimates the transmission path characteristics (distortion of the transmission path) from the SP signal (known signal) in the OFDM frame output from the FFT unit 62.

[0056] The equalization and symbol decision unit 64 performs equalization and symbol decision processing. Equalization is the process of dividing the FFT output signal by a transmission channel estimation value. This process removes distortion from the transmission channel. Symbol decision is the process of rearranging the equalized signal to the closest constellation point. This process removes noise added in the transmission channel. This equalization and symbol decision process deletes the TxID signal information of the master station. The OFDM frame signal with noise and other additives added is output to the IFFT unit 65. Thereafter, the relay station 300 adds a TxID that identifies the relay station to the OFDM signal after IFFT and GI addition.

[0057] The IFFT unit 65 performs IFFT (Inverse Fast Fourier Transform) processing on the input OFDM frame to generate an effective symbol signal, which is output to the GI adding unit .

[0058] The GI adding units 28 (281, 282) add a guard interval, which is a signal obtained by copying a portion of the end of the effective symbol signal, to the beginning of the effective symbol signal input from the IFFT unit 27. The guard interval is set so that the delay time of the multipath delay wave does not exceed the guard interval length. The signal to which the guard interval has been added has a TxID added in an adder 69, and is output as a signal output.

[0059] The TxID generation unit 67 generates a TxID, which is identification information for identifying the own device (relay station 300). The generated TxID is BPSK modulated and output to the attenuator 68. The attenuator 68 attenuates the signal level (signal power) of the TxID signal output from the TxID generation unit 67. The functions and processing contents of the TxID generation unit 67, attenuator 68, and adder 69 are similar to those of the TxID generation unit 40a, attenuator 41a, and adder 42a of the transmitting device 100.

[0060] As described above, in a broadcasting system that transmits broadcast signals using the FDM modulation method, the transmitting device 100 and the relay station 300 multiplex identification information for identifying their own devices onto FDM subcarriers on the time axis of the broadcast signal and transmit the multiplexed information. Therefore, according to this embodiment, the receiving side of the broadcast signal can identify the device that transmitted or relayed the broadcast signal.

[0061] Furthermore, the transmitting device 100 and the relay station 300 multiplex the identification information onto FDM subcarriers on the time axis of the broadcast signal so that the bandwidth for transmitting the identification information is equal to or less than the partial reception bandwidth, and transmit the identification information. Therefore, according to this embodiment, it is possible to reduce the impact on the main line system caused by assigning the identification information.

[0062] Furthermore, receiving device 200 receives a broadcast signal from transmitting device 100 or relay station 300, analyzes the received broadcast signal, and acquires identification information, thereby being able to identify transmitting device 100 that transmitted the broadcast signal or relay station 300 that relayed the broadcast signal. When receiving broadcast signals from multiple transmitting devices 100 or relay stations 300, receiving device 200 can identify transmitting device 100 or relay station 300 that transmitted each signal by calculating the correlation between each broadcast signal and the signal of the identification information, and can also determine the signal level and arrival time.

[0063] Relay station 300 also receives the broadcast signal transmitted from transmitting device 100 and corrects distortion in the transmission path from the received broadcast signal to remove noise, thereby removing the identification information of transmitting device 100 that was added by transmitting device 100. Relay station 300 adds identification information that identifies itself to the broadcast signal from which noise has been removed, and transmits the broadcast signal with the added identification information. Therefore, receiving device 200 that receives the broadcast signal relayed by relay station 300 can identify relay station 300 that relayed the broadcast signal by the identification information.

[0064] Second Embodiment (Transmitting device) FIG. 7 is a diagram showing an example of the configuration of a modulator in the transmitting device 101 that adds a TxID according to the second embodiment. In the second embodiment, the transmitting device 101 multiplexes the TxID onto an OFDM signal on the frequency axis. Furthermore, taking into consideration the impact on the data carrier, the transmitting device 101 multiplexes only onto the LLch (Low Latency Channel) carrier. The LLch corresponds to the AC (Auxiliary Channel) carrier of the current terrestrial broadcasting (ISDB-T). However, since the TxID signal acts as an interference component for the LLch signal, it is sufficiently attenuated before multiplexing. The LLch includes L0ch, a partial reception band, and L1ch, a non-partial reception band, and two types of content are transmitted via the LLch.

[0065] 7, the same components as those in FIG. 1A are assigned the same reference numerals, and detailed description thereof will be omitted. The configuration of the BICM unit 11 is shown in FIG. 1B, similar to that of the transmitting device 100. In the configuration of FIG. 1A, the transmitting device 100 assigns a TxID to the output of the GI adding unit 281. In contrast, the transmitting device 101 in FIG. 7 assigns a TxID to the LLch signal input to the input I / F unit 10.

[0066] The TxID generation unit 40b generates a TxID, which is identification information for identifying its own device (the transmitting device 101 in the example of FIG. 7). The TxID generated by the TxID generation unit 40b is BPSK modulated and output to the attenuator 41b. The attenuator 41b attenuates the signal level (signal power) of the TxID signal output from the TxID generation unit 40b. The attenuated TxID signal is added to the LLch by the adder 42b and output to the OFDM frame configuration units 261 and 262.

[0067] FIG. 8 is a diagram illustrating a detailed configuration example of the TxID generation unit 40b. In the configuration of FIG. 8, the TxID generation unit 40b includes a TxID signal generation unit 44, an error correction encoding unit 45, and a BPSK unit 46. The TxID signal generation unit 44 generates a TxID signal using individual bits rather than a code such as a Gold sequence. The error correction encoding unit 45 performs error correction encoding on the TxID signal. The BPSK unit 46 BPSK-modulates the error correction-encoded TxID signal and outputs it to the attenuator 41b. The functions and processing contents of the attenuator 41b and the adder 42b are similar to those of the attenuator 41a and the adder 42a of the transmitting device 100.

[0068] In this embodiment, the TxID is multiplexed onto the LLch carrier of the first symbol of the OFDM frame. Since the LLch is subjected to differential modulation in the symbol direction, the beginning of the OFDM frame is defined as a differential reference symbol (known signal). Therefore, the TxID is multiplexed onto the known signal.

[0069] 9A and 9B are diagrams showing an example of the number of LLch carriers in one symbol. FIG. 9A shows an example of the number of LLch carriers in compatible mode and normal mode when the FFT size is 8k (8192) points, 16k (16384) points, and 32k (32768) points. FIG. 9B shows an example of the number of L0ch and L1ch carriers in compatible mode and normal mode when the FFT size is 8k (8192) points. There are at least 66 LLch carriers in one symbol, and BPSK-modulated TxIDs are added to these carriers. One possible use of the 66 carriers (66 bits) is to use 14 bits as TxID information bits, perform error correction coding on these 14 bits, and use the remaining 52 bits as parity bits. Furthermore, since the number of carriers doubles in the cases of 16k and 32k, the transmitting device 101 may transmit the 66-bit TxID two or four times. Furthermore, the transmitting device 101 may multiplex the TxID onto only one of the L0ch and L1ch.

[0070] Although the method using the LLch carrier has been described here, multiplexing can also be performed on a TMCC carrier in the same manner. In this case, a TxID is assigned to the TMCC generated in the TMCC generation unit 24, and the TMCC to which the TxID has been assigned is output to the OFDM frame configuration units 261 and 262.

[0071] The modulator of the transmitting device 101 according to the second embodiment is configured in this manner. According to the transmitting device 101 according to this embodiment, the ID (TxID) specific to the transmitting station is multiplexed on the LLch rather than the mainline OFDM signal on the time axis, so that the TxID for identifying the device itself can be assigned to the signal without degrading the mainline signal. On the other hand, because the signals are multiplexed on the frequency axis, when signal waves from multiple stations are mixed, the receiving side cannot distinguish the delay time of each wave. Furthermore, it is possible to distinguish only the TxID of the wave with the highest level.

[0072] (receiving device) 10 is a diagram showing an example of the configuration of a receiving device 201 according to the second embodiment. The receiving device 201 includes a receiving unit 71, an FFT unit 72, a channel estimating unit 73, an LLch extracting unit 74, an equalizing unit 75, an LLch replica unit 76, an LLch replica removing unit 77, a TxID signal demodulating unit 78, and a TxID signal error correction decoding unit 79.

[0073] The receiver 71 receives broadcast waves, extracts OFDM symbols, and outputs them to the FFT unit 72. The FFT unit 72 performs OFDM demodulation processing on the OFDM symbols using FFT. As a result, the received signal is converted into a frequency-domain signal using FFT. The transmission path estimation unit 73 estimates transmission path characteristics (transmission path distortion) from the SP signal (known signal) in the output signal of the FFT unit 72. The estimation result is output to the equalization unit 75. The LLch extraction unit 74 extracts the LLch signal from the output signal of the FFT unit 72. Since the LLch is assigned to the subcarrier of the first symbol of a specific OFDM frame, it can be extracted by referencing that subcarrier. The equalization unit 75 performs equalization processing by dividing the LLch signal included in the output signal of the FFT unit 72 by the transmission path estimation value estimated by the transmission path estimation unit 73. The divided LLch signal is output to the LLch replica removal unit 77 as an equalized LLch signal.

[0074] The LLch replica unit 76 generates the LLch of the first symbol of the OFDM frame. The LLch of the first symbol of the OFDM frame is a known signal. The LLch replica removal unit 77 removes the LLch replica by subtracting the LLch replica generated by the LLch replica unit 76 from the LLch signal that has been equalized by the equalization unit 75. This extracts the TxID signal. The TxID signal demodulation unit 78 performs BPSK demodulation of the TxID extracted by the LLch replica removal unit 77. The TxID signal error correction decoding unit 79 performs error correction demodulation of the TxID.

[0075] (Relay station) 11 is a diagram showing an example of the configuration of a relay station 301 in the second embodiment. The relay station 301 includes a receiving unit 81, an FFT unit 82, a channel estimating unit 83, an equalization and symbol decision unit 84, a TxID generating unit 85, an attenuator 86, an adder 87, an IFFT unit 88, and a GI adding unit 89. Similar to the relay station 300 described with reference to FIG. 6, the relay station 301 performs equalization and symbol decision on the received signal to delete information on the TxID signal of the master station. Thereafter, by multiplexing the TxID of the relay station 301 onto the LL channel carrier, it becomes possible to assign a TxID for identifying each relay station 301.

[0076] The receiving unit 81, FFT unit 82, transmission channel estimating unit 83, equalization and symbol decision unit 84, TxID generating unit 85, attenuator 86, adder 87, IFFT unit 88, and GI adding unit 89 have the same functions as the receiving unit 61, FFT unit 62, transmission channel estimating unit 63, equalization and symbol decision unit 64, TxID generating unit 67, attenuator 68, adder 69, IFFT unit 65, and GI adding unit 66 of the relay station 300. However, the relay station 300 in FIG. 6 performs an inverse Fourier transform in the IFFT unit 65 and adds a TxID to the signal to which a GI has been added in the GI adding unit 66. In contrast, the relay station 301 in FIG. 11 adds a TxID to a symbol after the equalization decision in the equalization and symbol decision unit 84 and before the inverse Fourier transform in the IFFT unit 88.

[0077] As described above, in a broadcasting system that transmits broadcast signals using an FDM modulation scheme, the transmitting device 101 according to this embodiment multiplexes identification information for identifying itself onto FDM subcarriers on the frequency axis of the broadcast signal and transmits the identification information. Specifically, the transmitting device 101 multiplexes the identification information onto control data related to the transmission method of the LL channel or the broadcast signal, such as at least one of the LL channel and the TMCC carrier, which are known signals, and transmits the identification information. The relay station 301 also multiplexes the identification information of its own device onto control data related to the transmission method of the LL channel or the broadcast signal, such as at least one of the LL channel and the TMCC carrier, which are known signals, and transmits the identification information. Therefore, according to this embodiment, the identification information of the transmitting device 101 or the relay station 301 can be transmitted without degrading the main line signal.

[0078] The transmitting device 101 and the relay station 301 may multiplex the identification information onto L0ch or L1ch, which is a known signal, as control data and transmit the same. The transmitting device 101 and the relay station 301 may also multiplex the identification information onto FDM subcarriers on the frequency axis of the broadcast signal a number of times corresponding to the number of FFT samples used in modulation / demodulation processing and transmit the same.

[0079] Furthermore, as described above, LLch includes L0ch, which is a partial reception band, and L1ch, which is a non-partial reception band. The transmitting device 101 and relay station 301 may multiplex TxID only onto L0ch. This allows the identification information of the transmitting device 101 or relay station 301 to be transmitted without degrading the signal of L1ch, which is not multiplexed with TxID. In this case, the transmitting device 101 and relay station 301 may apply a band limit by reducing the clock rate of only TxID so that the bandwidth is equal to or less than the partial reception bandwidth (1.5 MHz). This reduces the impact on L0ch caused by assigning TxID.

[0080] <Third embodiment> (Transmitting device) The configuration of the transmitting device 101 according to the third embodiment is shown in FIG. 7, similarly to the second embodiment. FIG. 12 is a diagram illustrating an example of the configuration of a TxID generation unit according to this embodiment. As described with reference to FIG. 8, the TxID signal generation unit 44 of the TxID generation unit 40b according to the second embodiment generates a TxID signal using individual bits rather than a code such as a Gold sequence. In contrast, the TxID signal generation unit 44 of the TxID generation unit 40c according to the third embodiment generates a TxID signal using a code such as a Gold sequence that has excellent autocorrelation and cross-correlation values. Furthermore, in the transmitting device 101 according to the second embodiment, the TxID is multiplexed onto the LLch carrier of the first symbol of the OFDM frame. In contrast, in the transmitting device 101 according to this embodiment, the TxID is multiplexed across multiple OFDM symbols. The BPSK unit 46 has the same function as the BPSK unit 46 described with reference to FIG. 8.

[0081] As shown in FIG. 12, the TxID generation unit 40c includes a TxID signal generation unit 44 and a BPSK unit 46. The TxID is assigned by multiplexing it onto LLch carriers of several symbols starting from the first symbol of the OFDM frame. The TxID is also multiplexed onto signals other than known LLch signals. The TxID signal generation unit 44 generates a code with high autocorrelation, such as the Gold sequence (8191 bits) shown in FIG. 3. For example, when using 8kFFT in compatible mode, there are at least 66 LLch carriers within one symbol (see FIG. 9A), so the TxID signal generation unit 44 multiplexes over 125 symbols from the beginning of the frame (8191 / 66 = 124.1...). The TxID signal generation unit 44 may multiplex the TxID onto only either L0ch or L1ch. The TxID signal generation unit 44 may also multiplex onto LLch only within the partial reception band.

[0082] The modulator of the transmitting device 101 according to the third embodiment is configured as described above. According to the transmitting device 101 according to this embodiment, a transmitting station-specific ID (TxID) is multiplexed onto LLch on the time axis, rather than onto the mainline OFDM signal. Similarly, the relay station 301 multiplexes its own ID (TxID) onto LLch on the time axis, rather than onto the mainline OFDM signal. Therefore, a TxID for identifying the own device can be assigned to a signal without degrading the mainline signal. Furthermore, in this embodiment, since correlation values are calculated across multiple symbols, even when signal waves from multiple transmitting devices 101 or relay stations 301 are mixed, it is possible to identify the TxIDs of the multiple arriving transmitting devices 101 or relay stations 301, as well as their individual signal levels and delay times. In other words, it is possible to distinguish not only the wave with the highest level but also each of the multiple mixed signal waves, and to identify the signal level and delay time of each signal wave, as well as the transmitting device 101 or relay station 301 that output the signal wave.

[0083] (receiving device) 13 is a diagram showing an example of the configuration of a receiving device 202 according to this embodiment. The receiving device 202 includes a receiving unit 91, an FFT unit 92, a transmission channel estimating unit 93, an LLch extracting unit 94, an equalizing unit 95, an LLch demodulating / LLch replica creating unit 96, an LLch replica removing unit 97, a correlation calculating unit 98, a TxID generating unit 99, and a phase rotating unit 105. The receiving unit 91, the FFT unit 92, the transmission channel estimating unit 93, the LLch extracting unit 94, and the equalizing unit 95 have the same functions as the receiving unit 71, the FFT unit 72, the transmission channel estimating unit 73, the LLch extracting unit 74, and the equalizing unit 75 described with reference to FIG.

[0084] That is, the FFT unit 92 converts the received signal received by the receiver 91 into a frequency-domain signal. Next, the transmission channel estimation unit 93 performs transmission channel estimation processing using the SP carrier on the received signal converted into the frequency-domain signal. In parallel with this, the LLch extraction unit 94 extracts the LLch carrier from the received signal. The equalization unit 95 performs equalization processing by dividing the LLch carrier by the transmission channel estimation value. The LLch demodulation / LLch replica creation unit 96 demodulates the LLch from the equalized signal to create an LLch replica. That is, the LLch demodulation / LLch replica creation unit 96 generates the LLch (known signal) of the first symbol of the OFDM frame. Furthermore, the LLch demodulation / LLch replica creation unit 96 performs BPSK demodulation on symbols other than the first symbol. The LLch replica removal unit 97 removes this replica from the equalized signal to extract the TxID signal.

[0085] On the other hand, the TxID generation unit 99 generates a TxID using a code with excellent autocorrelation and cross-correlation values, such as the Gold sequence described with reference to Fig. 3. Furthermore, the TxID generation unit 99 performs BPSK modulation on the generated TxID.

[0086] The phase rotation unit 105 rotates the phase of the TxID generated by the TxID generation unit. That is, the phase rotation unit 105 rotates the phase of the TxID signal. jθ Multiplying by this gives the phase rotation. Here, θ=2πki / N, k is the variable (number of samples) that determines the rotation angle, i is the subcarrier number, and N is the FFT size. For example, if the FFT size is 8192 and the effective symbol length is 1296 μs, changing k from 0 to 800 corresponds to a delay of approximately 0 to 126 μs. This is because the FFT sample clock is 6.32...(=8192 / 1296) [MHz], and for a sample count of 800, the delay is 800 / 6.32=126.56 [μs].

[0087] The correlation calculation unit 98 calculates a different correlation value for each TxID by calculating the correlation between the TxID signal extracted by the LLch replica removal unit 97 and the unique TxID generated by the TxID generation unit 99 while changing the phase of the TxID. The correlation calculation is performed by adding the product of two signals. The difference between these correlation values indicates the level from the transmitting device 101 or relay station 301. Furthermore, the phase difference between the TxIDs for which correlation is detected corresponds to the delay time between the stations.

[0088] In a broadcasting system that transmits broadcast signals using an FDM modulation scheme, the transmitting device 101 according to this embodiment multiplexes identification information for identifying itself onto FDM subcarriers on the frequency axis of the broadcast signal and transmits the multiplexed information. Specifically, the transmitting device 101 multiplexes its identification information onto multiple symbols, starting from the first symbol of control data related to the transmission method of the broadcast signal, and transmits the multiplexed information. Similarly, the relay station 301 multiplexes its identification information onto multiple symbols, starting from the first symbol of control data related to the transmission method of the broadcast signal, and transmits the multiplexed information. Therefore, according to this embodiment, it is possible to transmit the identification information of the transmitting device 101 or the relay station 301 without degrading the mainline signal. Furthermore, according to this embodiment, when multiple signals are transmitted from the transmitting device 101 and the relay station 301, the receiving side can identify the transmitting device 101 and the relay station 301 that transmitted each signal and determine the signal level and arrival time.

[0089] Furthermore, relay station 301 receives the broadcast signal transmitted from transmitting device 101, removes noise from the received broadcast signal, assigns identification information for identifying itself to the noise-removed broadcast signal, and transmits the broadcast signal with the added identification information. Therefore, receiving devices 201 and 202 that receive the broadcast signal relayed by relay station 301 can identify relay station 301 that relayed the broadcast signal by the identification information.

[0090] The transmitting device 101 and the relay station 301 may multiplex the identification information onto L0ch or L1ch, which is a known signal, as control data and transmit the same. The transmitting device 101 and the relay station 301 may also multiplex the identification information onto FDM subcarriers on the frequency axis of the broadcast signal a number of times corresponding to the number of FFT samples used in modulation / demodulation processing and transmit the same. The configuration of this embodiment is applicable to digital broadcasting systems that use FDM, and is applicable to ISDB-T as well as the Advanced Terrestrial Broadcasting Standard.

[0091] The transmitting devices 100, 101 and relay stations 300, 301 in the above embodiments assign TxIDs to identify themselves and multiplex them onto transmission signals. In FDM, there is no preamble signal, and OFDM symbols containing data carriers are always transmitted. Therefore, in this embodiment, the TxID is multiplexed onto several symbols at the beginning of an OFDM frame. Specifically, the TxID is multiplexed onto a signal on the time axis or a signal on the frequency axis. Therefore, in an advanced terrestrial broadcasting system using FDM, it is possible to determine from which transmitting device 100, 101 or relay station 300, 301 a received broadcast wave has arrived, using the TxID. Therefore, each embodiment is effective for investigating interference within a broadcast area.

[0092] The present disclosure is not limited to the above-described embodiments. For example, multiple blocks shown in the block diagrams may be integrated, or one block may be divided. Multiple steps shown in the flowcharts may be executed in parallel or in a different order depending on the processing capabilities of the device executing each step, or as needed, instead of being executed in chronological order as described. Other modifications are possible without departing from the spirit of the present disclosure. [Explanation of symbols]

[0093] 10 Input I / F 11 BICM Department 14 Level adjustment section 15 System separation section 16 Layer synthesis section 17 Band division section 18 hour IL part 19 Frequency IL section 20 Band synthesis section 21 MISO encoder 22 TMCC information bit generator 23 Synchronous bit generator 24 TMCC generation section 25 Pilot Generation Unit 26 OFDM frame configuration section 27,65,88 IFFT section 28,66,89 GI adduct 31 Energy diffusion section 32 BCH encoder 33 LDPC encoding section 34 Mapping section 40a,40b,67,85,99 TxID generation section 41a, 41b, 68, 86 Attenuators 42a, 42b, 69, 87 adder 44 TxID signal generation section 45 Error correction coding section 46 BPSK section 61,71,81,91 Receiver 62,72,82,92 FFT section 63,73,83,93 Transmission path estimation section 64,84 Equalization and symbol decision section 74,94 LLch outlet 75,95 Equalization section 76 LLch replica part 77,97 LLch replica removal section 78 TxID signal demodulation section 79 TxID signal error correction decoding unit 96 LLch demodulation / LLch replica creation section 98 Correlation Calculation Unit 100,101 Transmitting device 105 Phase Rotation Unit 200, 201, 202 receiving device 300,301 relay station

Claims

1. In a broadcasting system that transmits broadcast signals using an FDM modulation method, Identification information for identifying the device itself is control data relating to a transmission method of the broadcast signal in FDM subcarriers on the frequency axis of the broadcast signal, and is multiplexed onto at least one of LLch and TMCC carriers, which are known signals, and transmitted. Transmitting device.

2. The transmitting device according to claim 1 , wherein the identification information is multiplexed into a plurality of symbols starting from the first symbol of the control data and transmitted.

3. 3. The transmitting device according to claim 1, wherein the identification information is multiplexed onto a known signal, L0ch or L1ch, as the control data and transmitted.

4. 4. The transmitting device according to claim 1, wherein the identification information is multiplexed onto the FDM subcarriers on the frequency axis of the broadcast signal a number of times corresponding to the number of FFT samples used in modulation / demodulation processing and transmitted.

5. In a broadcasting system that transmits broadcast signals using an FDM modulation method, Identification information for identifying the device itself is control data relating to a transmission method of the broadcast signal in FDM subcarriers on the time axis of the broadcast signal, and is multiplexed onto at least one of LLch and TMCC carriers, which are known signals, and transmitted. Transmitting device.

6. 6. The transmitting device according to claim 5, wherein the identification information is multiplexed onto FDM subcarriers on the time axis of the broadcast signal and transmitted so that the bandwidth for transmitting the identification information is equal to or less than a partial reception bandwidth.

7. receiving the broadcast signal from the transmitting device according to any one of claims 1 to 6; analyzing the received broadcast signal to obtain the identification information; Receiving device.

8. receiving the broadcast signal transmitted from the transmitting device according to any one of claims 1 to 6; removing noise from the received broadcast signal; control data relating to a transmission method of the broadcast signal in FDM subcarriers on a frequency axis or a time axis of the broadcast signal from which the noise has been removed, the control data being multiplexed and assigned to at least one of an LLch and a TMCC carrier, which are known signals, and identification information for identifying the device itself; transmitting the broadcast signal to which the identification information is assigned; Relay station.

Images