KR101590013B1 - Transmitting/receiving system and method of processing data in the transmitting/receiving system - Google Patents

Abstract

A transmission / reception system and a data processing method for transmitting and receiving mobile service data are disclosed. The receiving system may include a demodulator, a pre-signaling decoder, a post-signaling decoder, and a block decoder. One transmission frame is composed of a plurality of subframes, one subframe is made up of a plurality of slots, and the demodulator is allocated to some segments of at least one slot based on the decoded pre-signaling data, Demodulate the data. The pre-signaling decoder decodes the pre-signaling data allocated to the first slot of the sub-frame and outputs the decoded pre-signaling data to the demodulator. The post signaling decoder decodes the post signaling data allocated and received after the pre-signaling data. And the block decoder turbo decodes the demodulated mobile service data based on the decoded post signaling data.

Description

TECHNICAL FIELD [0001] The present invention relates to a transmission / reception system and a data processing method,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission system for transmitting digital broadcasting, a reception system for receiving digital broadcasting transmitted from a transmission system, and a data processing method for the transmission / reception system.

VSB (Vestigial Sideband) transmission system adopted as a digital broadcasting standard in North America and Korea in digital broadcasting is a single carrier system, so reception performance of a receiving system may be deteriorated in a poor channel environment. Particularly, in the case of a portable or mobile broadcasting receiver, robustness against channel change and noise is further required. Therefore, when the mobile service data is transmitted in the VSB transmission method, the reception performance of the receiving system is further reduced.

It is an object of the present invention to provide a transmission / reception system and a data processing method that are robust against channel changes and noise.

Another object of the present invention is to provide a transmission / reception system and a data processing method for improving the reception performance of a receiving system by inserting known data known by the promise of a transmitting / .

It is another object of the present invention to provide a transmission / reception system and a data processing method for providing mobile services of different formats.

It is still another object of the present invention to provide a transmission / reception system and a data processing method for providing a mobile service using a full channel.

In order to achieve the above object, a receiving system according to an embodiment of the present invention may include a demodulator, a pre-signaling decoder, a post signaling decoder, and a block decoder. One transmission frame is composed of a plurality of subframes, one subframe is made up of a plurality of slots, and the demodulator is allocated to some segments of at least one slot based on the decoded pre-signaling data, Demodulate the data. The pre-signaling decoder decodes the pre-signaling data allocated to the first slot of the sub-frame and outputs the decoded pre-signaling data to the demodulator. The post signaling decoder decodes the post signaling data allocated and received after the pre-signaling data. And the block decoder turbo decodes the demodulated mobile service data based on the decoded post signaling data.

The last segment of the slot to which the mobile service data is allocated is allocated with a predetermined known data sequence by the promise of the transmitting / receiving side.

Wherein when the mobile service data is data for a second mobile service and data for a first mobile service is allocated to a segment of a slot to which the mobile service data is allocated, / A predetermined known data sequence is assigned and received by the appointment of the receiving side.

The block decoder performs trellis decoding on mobile service data for the second mobile service, and then performs turbo decoding on a PCCC (Parallel Concatenated Convolutional Code) method.

A data processing method of a receiving system according to an embodiment of the present invention is characterized in that one transmission frame is composed of a plurality of subframes, one subframe is composed of a plurality of slots, Demodulating mobile service data received and assigned to some segment of a slot; Decoding pre-signaling data allocated and received in a first slot of the sub-frame; Decoding the post signaling data allocated and received after the pre-signaling data; And turbo decoding the demodulated mobile service data based on the decoded post signaling data.

Other objects, features and advantages of the present invention will become apparent from the detailed description of embodiments with reference to the accompanying drawings.

The transmission / reception system and the data processing method according to the present invention are advantageous in error when transmitting mobile service data through a channel. Particularly, the present invention is advantageous in that mobile service data can be received without error even in a channel with ghost and severe noise. The present invention can improve reception performance of a receiving system in an environment where a channel change is severe by inserting and transmitting known data at a specific location in a data area.

In addition, the present invention can process not only data for a first mobile service received through a part of a channel but also data for a second mobile service received through a full channel to service the user.

Particularly, the present invention is more effective when applied to portable and mobile receivers where channel changes are severe and robustness against noise is required.

1 is a diagram showing an example of an FC-M / H frame structure for transmission and reception of mobile service data according to the present invention;
2 is a diagram showing an example of a general VSB frame structure;
FIG. 3 is a diagram illustrating a mapping example of the first 4 M / H slot positions of an M / H subframe for one VSB frame in the spatial domain
4 is a diagram showing an embodiment of a structure of a data group after data interleaving according to the present invention.
5 is an enlarged view of a part of Fig. 4
6 is a diagram showing an example of a data grouping order allocated to one M / H subframe among five M / H subframes constituting an FC-M / H frame according to the present invention.
7 is a diagram showing an example of allocating data for a first mobile service of a single parade to one FC-M / H frame according to the present invention
8 is a diagram showing an example of allocating data for a first mobile service of three parades to one M / H subframe according to the present invention
9 is a view showing an example of allocating data for a first mobile service of three parades to one M / H subframe according to the present invention and allocating base data for a second mobile service
10 is a diagram showing an example of a known data sequence for a second mobile service having a two-segment length according to the present invention;
11A and 11B are diagrams for explaining a method for allocating data for a first mobile service and a known data sequence for a second mobile service in one M / H subframe according to the present invention, A drawing showing an example of allocating data for a mobile service
12 is a block diagram showing an example of a transmission system according to the present invention
13 is a detailed block diagram illustrating an example of a first RS frame encoder according to the present invention.
14A to 14C are diagrams showing an example of a process of performing error correction coding and error detection coding on an RS frame payload according to the present invention
15 is a view showing an example of an RS frame payload structure according to the present invention;
16 is a diagram showing an example of an M / H header structure in an M / H service data packet according to the present invention.
17 (a) and 17 (b) are views showing an embodiment of a process of dividing an RS frame for a first mobile service according to the present invention
18 is a detailed block diagram illustrating an example of a second RS frame encoder according to the present invention.
19 is a diagram showing an example of an RS frame for a second mobile service in which error correction coding and error detection coding are performed according to the present invention;
20 (a) and 20 (b) are views showing an embodiment of a process of dividing an RS frame for a second mobile service according to the present invention
21 is a block diagram showing an embodiment of a second block processor according to the present invention
22 (a) and 22 (b) are diagrams showing an example of a pre-signaling data structure used for detecting a training mode according to the present invention
23 is a diagram showing an example of allocating known data, pre-signaling data, and post-signaling data for an M / H subframe according to the present invention to an M / H subframe
24 is a block diagram showing an embodiment of a second signaling code according to the present invention.
25 is a block diagram showing an embodiment of a demodulation unit in a reception system according to the present invention

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The structure and operation of the present invention shown in the drawings and described by the drawings are described as at least one embodiment, and the technical ideas and the core structure and operation of the present invention are not limited thereby.

Definitions of terms used in the present invention

The terms used in the present invention are selected from general terms that are widely used in the present invention while considering the functions of the present invention. However, the terms may vary depending on the intention or custom of the artisan or the emergence of new technology. Also, in certain cases, there may be a term selected arbitrarily by the applicant, in which case the meaning thereof will be described in detail in the description of the corresponding invention. Therefore, it is to be understood that the term used in the present invention should be defined based on the meaning of the term rather than the name of the term, and on the contents of the present invention throughout.

Among the terms used in the present invention, main service data may include audio / video (A / V) data as data that can be received by a fixed receiving system. That is, the main service data may include HD (High Definition) or SD (Standard Definition) A / V data, and various data for data broadcasting may be included. The known data is previously known data by the promise of the transmitting / receiving side.

Among the terms used in the present invention, M / H (or MH) is the first letter of each of a mobile and a handheld, and is a concept opposite to a fixed type. The M / H service data includes at least one of mobile service data and handheld service data. For convenience of explanation, the M / H service data is also referred to as mobile service data. At this time, the mobile service data may include not only M / H service data but also service data indicating movement or carrying, so that the mobile service data will not be limited to the M / H service data.

The mobile service data defined above may be data having information such as a program executable file, stock information, etc., or A / V data. In particular, the mobile service data may be service data for a portable or mobile terminal (or broadcast receiver), and may be A / V data having a smaller resolution and smaller data rate than the main service data. For example, if the A / V codec used for the existing main service is an MPEG-2 codec, the A / V codec for mobile service may be MPEG-4 Advanced Video Coding (AVC), and Scalable Video Coding (SVC). Also, any kind of data can be transmitted with the mobile service data. For example, TPEG (Transport Protocol Expert Group) data for broadcasting traffic information in real time can be transmitted as mobile service data.

The data service using the mobile service data may include a weather service, a traffic service, a securities service, a viewer participation quiz program, a real-time opinion survey, an interactive education broadcast, a game service, a plot of a drama, Providing information on programs by service, media, hourly, or topic that enables information service for information, information on past competitions of sports, profiles and grades of athletes, and product information and orders Or the like, and the present invention is not limited thereto.

The present invention can transmit data for a mobile service using a part of a channel capacity in which data for a main service is transmitted, or transmit data for a mobile service using all channel capacity, Data may be transmitted.

For convenience of explanation, the mobile service provided by using a part of the channel capacity like the former is referred to as a first mobile service (or M / H 1.0 service), and the mobile service data at this time is referred to as a first mobile service data (Or M / H 1.0 service data). (Or M / H 2.0 service), and the mobile service data at this time is referred to as a second mobile service data (or M / H 2.0 service data) .

The data for the first mobile service is data necessary for the first mobile service, including the first mobile service data, the known data for the first mobile service, and the signaling data for the first mobile service. The signaling data includes transmission parameter channel (TPC) data and fast information channel (FIC) data.

The data for the second mobile service is data necessary for the second mobile service, including the second mobile service data, the known data for the second mobile service, and the signaling data for the second mobile service. The signaling data includes pre-signaling data and post signaling data, and the post-signaling data includes TPC data and FIC data. In addition, the TPC data includes common-TPC data and parade-TPC data. A detailed description of each signaling data will be described later.

The present invention may transmit only the data for the second mobile service or simultaneously transmit the data for the first mobile service and the data for the second mobile service.

The transmission unit of the data for the first mobile service and the data for the second mobile service is an FC-M / H frame (also referred to as an M / H frame). For example, only data for the second mobile service may exist on one FC-M / H frame, and data for the first mobile service and data for the second mobile service may coexist.

At this time, one FC-M / H frame is composed of K1 M / H subframes (or subframes), one M / H subframe is composed of K2 VSB frames, one VSB frame is K3 (Or slot) M / H slots. In the present invention, K1 is set to 5, K2 is set to 4, and K3 is set to 4. The values of K1, K2, and K3 suggested by the present invention are preferred embodiments or merely examples, and the scope of the present invention is not limited to the above values.

FIG. 1 shows an embodiment of an FC-M / H frame structure for transmitting / receiving data for first and second mobile services according to the present invention. 1 shows that one FC-M / H frame is composed of five M / H subframes, one M / H subframe is composed of four VSB frames, one VSB frame is composed of four M / H slots As shown in FIG. In this case, one FC-M / H frame includes five M / H subframes, 20 VSB frames, and 80 M / H slots.

And one M / H slot is made up of 156 segments (or segments). This is half the size of the VSB field. At this time, two VSB fields are gathered to form one VSB frame.

FIG. 2 shows an example of a VSB frame structure. One VSB frame includes two fields (i.e., an odd field and an even field). Each field is composed of one field sync segment and 312 segments. That is, it can be seen that two M / H slots are gathered to form one field, and two fields are gathered to form one VSB frame. Therefore, one M / H slot includes 156 segments.

FIG. 3 shows an embodiment of an M / H slot structure according to the present invention. The M / H slot is a basic time period for multiplexing data for a first mobile service and data for a second mobile service. One M / H slot may contain only data for the second mobile service or all of the data for the first and second mobile services.

FIG. 3 shows a mapping example of the first 4 M / H slot positions of an M / H subframe in a space region for one VSB frame.

3, the first segment (# 0) of the first M / H slot (M / H Slot # 0) is mapped to the first segment of the odd VSB field and the second M / H slot 1) is mapped to the 157th segment of the odd VSB field. Also, the first segment (# 0) of the third M / H slot (M / H Slot # 2) is mapped to the first segment of the even VSB field, The first segment (# 0) is mapped to the 157th segment of the even VSB field. Likewise, the remaining 12 M / H slots in the corresponding M / H subframe are mapped in the same way to the following VSB frame.

In one embodiment, if only data for a second mobile service is transmitted in one FC-M / H frame, a second mobile service is assigned to each M / H slot (i.e., 156 segments) in the FC-M / Data can be allocated and transmitted.

In another embodiment, if data for the first mobile service and data for the second mobile service are transmitted together in one FC-M / H frame, data for the first mobile service is transmitted to the FC-M / And allocates data for the second mobile service to the remaining area in the FC-M / H frame, and transmits the data.

Here, data for the first mobile service is allocated to a part of a specific M / H slot in the FC-M / H frame according to a predetermined rule and transmitted. The data for the first mobile service may be allotted to 80 M / H slots in the FC-M / H frame or may be allocated to some M / H slots among 80 M / H slots. At this time, data for the first mobile service is allocated to a certain segment of the corresponding M / H slot.

For example, if data for the first mobile service is assigned to the first M / H slot of each M / H subframe and the 96th segment of the fifth M / H slot in the FC-M / H frame, Data for the first M / H sub-frame and the remaining 60 segments of the 5th M / H slot in each M / H sub-frame in the FC-M / It can be assigned to 156 segments of M / H slot.

According to an embodiment of the present invention, the data for the first mobile service constitutes a data group, and one data group is allocated to one M / H slot.

One data group can be divided into one or more layered areas, and each area in the data group can be classified based on reception performance in a data group, for example.

In the present invention, one data group is divided into A, B, C, and D regions as an embodiment.

FIG. 4 is a diagram in which one data group is divided into a plurality of segments, and FIG. 5 is an enlarged view of a portion of the data group of FIG. 4 for better understanding of the present invention.

That is, the data structure as shown in FIG. 4 is transmitted to the receiving system. FIG. 4 shows an example in which one data group is distributed over 170 segments.

FIG. 4 shows an example in which a data group is divided into 10 M / H blocks (M / H blocks B1 to B10). And each M / H block has a length of 16 segments. In FIG. 4, only the RS parity data position holders are allocated to some of the five segments preceding the M / H block B1 and the five segments after the M / H block B10, which are excluded from the A region to the D region of the data group do.

That is, assuming that one data group is divided into A, B, C, and D regions, each M / H block is divided into any one of the A region to the D region according to the characteristics of each M / Can be included.

In the case of M / H block B4 to M / H block B7 in the data group of Fig. 4, a long known data row is inserted before and after each M / H block. (= B4 + B5 + B6 + B7) including the M / H block B4 to the M / H block B7 having the known data sequence. As described above, in the case of the A region having the known data sequence for each M / H block back and forth, the receiving system can perform equalization using the channel information obtained from the known data. Thus, the most robust equalization Performance can be obtained.

In the case of the M / H block B3 and the M / H block B8 in the data group of FIG. 4, there is a long known data row only on one side of each M / H block. That is, in the M / H block B3, a long known data sequence exists only after the corresponding M / H block, and the M / H block B8 has a long known data sequence only in front of the corresponding M / H block. In the present invention, the B region (= B3 + B8) including the M / H block B3 and the M / H block B8 will be described. As described above, in the case of the B region in which the known data sequence exists in only one of the M / H blocks, the receiving system can perform equalization using the channel information obtained from the known data, A strong equalizing performance can be obtained.

In the case of the M / H block B2 and the M / H block B9 in the data group of FIG. 4, it is impossible to insert a long known data row back and forth in both M / H blocks. In the present invention, a C region (= B2 + B9) including the M / H block B2 and the M / H block B9 will be described.

Likewise, in the case of the M / H block B1 and the M / H block B10 in the data group of Fig. 4, it is impossible to insert a long known data row back and forth in both M / H blocks. In the present invention, the D region (= B1 + B10) including the M / H block B1 and the M / H block B10 will be described. Since the C / D region is far away from the known data sequence, the reception performance may be poor if the channel changes rapidly.

The size of the data group, the number of layered areas in the data group and the size of each area, the number of M / H blocks included in each area, the size of each M / H block, The present invention is not limited to the above-mentioned examples.

6 shows an example of a data group allocation procedure to be assigned to one M / H subframe among five M / H subframes constituting an FC-M / H frame. As an example, the method of allocating data groups may be applied equally to all FC-M / H frames and may be different for each FC-M / H frame. It is also applicable to all M / H subframes within one FC-M / H frame, or may be applied to each M / H subframe differently. At this time, assuming that the allocation of the data group is equally applied to all M / H subframes in the FC-M / H frame, the number of data groups allocated to one FC-M / H frame is a multiple of 5.

And consecutive multiple data groups are allocated as far as possible from each other in the M / H subframe. This makes it possible to strongly respond to burst errors that may occur in one M / H subframe.

For example, assuming that three groups are allocated to one M / H subframe, the first M / H slot (M / H Slot # 0), the fifth M / H slot M / H Slot # 4) and the ninth M / H slot (M / H Slot # 8).

6 shows an example in which 16 data groups are allocated to one M / H subframe by applying the allocation rule, and 0, 8, 4, 12, 1, 5, , 6, 14, 3, 11, 7, and 15 in the order of 16 M / H slots.

Equation (1) is a mathematical expression of rules for assigning data groups to one M / H subframe as described above.

Where O = 0 if i < 4,

        O = 2 else if i <8,

        O = 1 else if i <12,

        O = 3 else.

The j is an M / H slot number in one M / H subframe, and may have a value between 0 and 15. The i is a data group number, and may have a value between 0 and 15.

When allocating one data group to one M / H slot by applying the allocation rule shown in Equation (1), only the data of the A / B area in the data group, that is, data corresponding to the 96 segments, / H &lt; / RTI &gt;

For example, assuming that three data groups are allocated to one M / H subframe, the first M / H slot (M / H Slot # 0), the fifth M / H slot The data of the A / B area in the corresponding data group is allocated to each of the 96 segments of the M / H slot # 4 (M / H Slot # 4) and the ninth M / H slot (M / H Slot # 8).

Meanwhile, the present invention refers to a group of data groups having the same FEC parameter in the FC-M / H frame and mapped to the same RS frame as a parade for the first mobile service (i.e., M / H 1.0 service) .

A group of segments having the same FEC parameter in the FC-M / H frame and mapped to the same RS frame will be referred to as a parade for the second mobile service (i.e., M / H 2.0 service).

That is, the parade for the first mobile service is also mapped to one RS frame, and the parade for the second mobile service is also mapped to one RS frame.

In addition, the first mobile service data in one RS frame may be all allocated to the A / B / C / D area in the data group, or may be allocated to only the A / B area and the C / D area. That is, in the latter case, the RS frame allocated to the A / B area in the data group is different from the RS frame allocated to the C / D area. For convenience of explanation, the RS frame allocated to the A / B area in the data group is referred to as a primary RS frame, and the RS frame allocated to the C / D area is referred to as a secondary RS frame frame. Also, the RS frame allocated to the A / B / C / D area in the data group may be referred to as a primary RS frame.

The present invention allocates the first mobile service data in one RS frame to the A / B area in the data group as one embodiment.

That is, in the RS frame mode, one parade transmits the primary RS frame allocated to all of the A / B / C / D areas in the data group, the primary RS frame allocated to the A / B area in the data group And transmits at least one of the RS frame and the secondary RS frame allocated to the C / D area.

Table 1 below shows an example of the RS frame mode.

In Table 1, 2 bits are allocated to indicate the RS frame mode. Referring to Table 1, when the RS frame mode value is 00, it indicates that one parade transmits primary RS frames all allocated to the A / B / C / D areas in the data group. When the RS frame mode value is 01, it indicates that one parade transmits at least one of a primary RS frame allocated to the A / B area in the data group and a secondary RS frame allocated to the C / D area. One or more parades are sent in one FC-M / H frame.

7 is a diagram showing an example of transmitting a single parade in one FC-M / H frame for the first mobile service. That is, FIG. 7 shows an embodiment in which a single parade with three data groups included in one M / H subframe is allocated to one FC-M / H frame.

Referring to FIG. 7, three data groups are sequentially allocated in one M / H subframe at a period of 4 M / H slots, and this process is performed for five M / H subframes in the corresponding FC-M / , 15 data groups are allocated to one FC-M / H frame. Here, the 15 data groups are data groups included in one parade. Therefore, one M / H subframe is composed of four VSB frames, but one M / H subframe includes three data groups. Therefore, one VSB frame among four VSB frames in one M / H subframe The data group of the parade is not allocated.

On the other hand, if a plurality of parades are transmitted in one FC-M / H frame for the first mobile service, it is also possible to assign parades away from each other as far as possible in the M / H subframe For example. That is, data groups in other parades assigned to one FC-M / H frame are also allocated to each 4 M / H slot period.

At this time, the data group of another parade may be allocated in a circular manner from the M / H slot to which the data group of the previous parade is not allocated. For example, assuming that the allocation of the data group for one parade is made as shown in FIG. 7, the data group for the next parade is allocated from the 12th M / H slot in one M / H subframe. This is one example, and for another example, the data group of the next parade may be sequentially transmitted from one M / H subframe to another M / H slot, for example, from a third M / H slot to a 4 M / H slot period It can also be assigned.

This makes it possible to strongly respond to burst errors that may occur in one M / H subframe.

And the parade allocation method can be applied differently for FC-M / H frame based on FC-M / H frame, and can be applied to all FC-M / H frames equally. It is also applicable to all M / H subframes within one FC-M / H frame, or may be applied to each M / H subframe differently. The present invention is applicable to all M / H subframes within one FC-M / H frame, and may be applied to all FC-M / H frames. That is, the FC-M / H frame structure can be changed in units of FC-M / H frames, which enables frequent and flexible adjustment of the ensemble data rate.

When data groups for at least one parade are allocated for a first mobile service in one FC-M / H frame, data for the second mobile service is allocated between the data group and the data group.

8 shows an example of a case where three parades (Parade # 0, Parade # 1, Parade # 1, and Parade # 2) are provided for a first mobile service in one M / H subframe among five M / H subframes constituting one FC- 2) is allocated to the second parade, the data for the second mobile service is allocated between the data groups of the first to third parades.

Assuming that the first parade (# 1) includes three data groups per M / H subframe (NOG = 3), the positions of the groups in the M / H subframe are 0 to 2 . &Lt; / RTI &gt; That is, the data groups of the first parade are sequentially arranged in the first, fifth, and ninth M / H slots (M / H Slot # 0, M / H Slot # 4, M / H Slot # . Assuming that the second parade (# 2) also includes three data groups per M / H subframe (NOG = 3), the positions of the groups in the M / H subframe are 3 to 5 Can be obtained by substitution. That is, the data groups of the second parade are sequentially arranged in the third, seventh and seventh M / H slots (M / H Slot # 12, M / H Slot # 2, M / H Slot # 6) in the M / H subframe . Assuming that the third parade (# 3) includes four groups per M / H subframe (NOG = 4), the positions of the groups in the M / H subframe are 6 to 9 in the i value of the above- Can be obtained by substitution. In other words, the eleventh, fifteenth, second and sixth M / H slots (M / H Slot # 10, M / H Slot # 14, M / H Slot # 1, M / H Slot # ) Are sequentially assigned to the data groups of the third parade. In this manner, data groups for a plurality of parades can be allocated to one FC-M / H frame, and allocation of data groups in one M / H subframe has a group space of 4 M / H slots, Is being performed in serial.

Therefore, the number of groups of one parade per sub-frame (NOG) that can be allocated to one M / H subframe can be any one of integers from 1 to 8 . In this case, since one FC-M / H frame includes 5 M / H subframes, the number of data groups of one parade that can be allocated to one FC-M / H frame is 5 to 40 Or a multiple of &lt; / RTI &gt;

At this time, only the data of the A / B area in the data group is allocated to the corresponding M / H slot. Therefore, in the case of the M / H slot to which the data group is allocated, the first mobile service is allocated to 96 segments out of the total 156 segments of the corresponding M / Lt; / RTI &gt; Then, the data for the second mobile service may be allocated to the remaining segments in the M / H slot, that is, 60 segments. 8, M / H Slots # 0 to # 2, M / H Slots # 4 to # 7, and M / The data for the second mobile service may be allocated to 60 segments of the M / H slots # 6, M / H Slot # 8, M / H Slot # 10, M / H Slot # 12, and M / H Slot # 14.

Data for the second mobile service is also allocated to the M / H slot to which data for the first mobile service is not allocated. 8, for example, the fourth, eighth, tenth, twelfth, fourteenth and sixteenth M / H slots (M / H Slot # 3, M / H Slot # 7, M / H Slot # Data for the second mobile service may be allocated to 156 segments of the M / H Slot # 11, the M / H Slot # 13, and the M / H Slot # 15.

In the present invention, the data assignment for the first mobile service and the data assignment method for the second mobile service may be different for each FC-M / H frame, but in one FC-M / H frame It is an embodiment that the same holds for all M / H subframes.

When there is a data group for the first mobile service, data for the second mobile service is allocated to 60 segments of the M / H slot, and if not, the M Data for the second mobile service is allocated to the 156 segments of the / H slot.

The data for the second mobile service includes not only the second mobile service data but also a known data sequence (or training signal) for channel equalization. That is, the receiving system estimates the channel impulse response (CIR) using the known data sequence at the time of channel equalization.

The known data sequence for CIR estimation has a two-segment length.

The known data sequence for CIR estimation is inserted every 16 or 12 segments in the M / H slot to which data for the second mobile service is allocated.

9 shows a case where a known data sequence for CIR estimation of the second mobile service is allocated to an M / H slot of one M / H subframe among five M / H subframes constituting one FC-M / H frame For example.

According to the present invention, a method of allocating a base data sequence for CIR estimation of the second mobile service is differently applied depending on whether data for a first mobile service exists in an M / H slot to which data for a second mobile service is allocated As an embodiment.

For example, if data for a first mobile service exists in an M / H slot to which data for a second mobile service is allocated, a known data sequence is inserted in the first two segments of the 60 segments of the M / H slot , The known data sequence is inserted into the next two segments of the 12-segment. After the process of inserting the known data sequence into the next two segments of the 14 segments is repeated twice, the known data sequence is inserted into the last two segments of the next 2 segments of the 10 segments, that is, 60 segments.

As another example, when there is no data for the first mobile service in the M / H slot to which the data for the second mobile service is allocated, the base data string in the next two segments of the 14 segments of the 156 segments of the M / After the insertion process is repeated 9 times, the known data sequence is inserted into the last two segments of the next 2 segments of the 10 segments, that is, the 156 segments.

Thus, the known data sequence for the second mobile service is inserted every 16 or 12 segments in the M / H slot to which the data for the second mobile service is allocated. If 60 segments or 156 segments in one M / H slot are used for the second mobile service, the base data string is inserted into the last two segments of every 16 segments, and the base data string is inserted into the last two segments of the remaining 12 segments .

However, if 60 segments in one M / H slot are used for the second mobile service, i.e., if there is data for the first mobile service, the first two segments, immediately following the data for the first mobile service, In addition to the two segments, the known data row is inserted. At this time, FEC (Forward Error Correction) -coded second mobile service data is allocated to the remaining segments except the segments to which the known data sequence is allocated.

In the present invention, the first 24 symbols of each known data sequence are used for memory initialization of the intra-transmission-system trellis encoder as shown in FIG.

At this time, the states of all trellis encoders are zeroed by the pattern itself without special state termination at the end of each known data sequence. That is, at the end of each known data sequence, the memories of all trellis encoders are zeroed by the pattern of the corresponding known data sequence without any apparent trellis state termination (all memories of trellis encoder (or TCM encoder) become zeros by its pattern without any explicit trellis state termination).

Also, when there is only data for the second mobile service, the length of the known data sequence and the insertion period can be varied.

On the other hand, the data for the first mobile service is allocated (or arranged) in each M / H subframe in one FC-M / H frame, and the base data stream for the second mobile service And then allocates remaining data for the second mobile service to the remaining segments.

11A and 11B show an example in which data for the second mobile service is allocated in one M / H subframe.

For convenience of explanation, the present invention allocates the remaining area after allocating the data for the first mobile service and the known data sequence for the second mobile service in each M / H subframe in one FC-M / H frame 2 &lt; / RTI &gt; mobile service. 11A, for example, the white area becomes the data area for the second mobile service. 11, there is a data area for the first mobile service shown in FIG. 10, but this is not shown for convenience of explanation.

The data for the second mobile service further includes pre-signaling data and post signaling data as well as second mobile service data, known data. The post signaling data is composed of TPC data and FIC data.

At this time, pre-signaling data is allocated to the front of the data area for the second mobile service in every M / H subframe, and TPC data and FIC data are sequentially allocated thereafter. And allocates second mobile service data after the FIC data. If allocation of the second mobile service data and an area remaining in the data area for the second mobile service occurs, dummy data is assigned to that area as an embodiment. For example, if pre-signaling data, post-signaling data, and second mobile service data are assigned to the data area for the second mobile service and the area corresponding to the two segments remains, the dummy data is allocated to the two segments.

The second mobile service data corresponds to actual A / V data, and may be configured as a Type 1 parade and a Type 2 parade as shown in FIG. 11 (b). In this case, the second mobile service data of the type 1 parade is allocated after the FIC data in the data area for the second mobile service, and the second mobile service data of the type 2 parade is allocated after the mobile service data of the first type parade do.

The Type 1 Parade refers to having one slice in the M / H subframe, that is, one parade being transmitted one at a time in the M / H subframe. For example, assuming that there are three parades (Prd0, Prd1, and Prd2), after all the second mobile service data of Prd0 is allocated after the FIC data in the data area for the second mobile service, Prd1 All of the second mobile service data of the second mobile communication terminal. And finally allocates all the second mobile service data of Prd2.

The Type 2 parade refers to a parade having two or more slices in an M / H subframe. In this case, the length of each slice in the type 2 parade is the same, and the number and period of slices are the same in M / H subframes in one FC-M / H frame. That is, the second mobile service data of each parade is divided into the corresponding slice sizes by the number of slices, and then distributed and distributed to the respective slices.

For example, assuming that there are two parades (Prd3, Prd4) and three slices, the second mobile service data of Prd3 and the second mobile service data of Prd4 are allocated as shown in FIG. 11 (b) And are sequentially divided into three slices of the parade. At this time, the slice for Prd3 and the slice for Prd4 are alternately positioned and transmitted.

12 is a configuration block diagram showing an embodiment of a transmission system for transmitting data for the first mobile service and data for the second mobile service described up to now.

12, a first mobile service processor 110, a second mobile service processor 120, a symbol multiplexer 131, a trellis encoder 132, a synchronous multiplexer 133, a pilot inserter 134, a modulator 135, and an up-converter 136. A pre-equalizer filter may optionally be included.

The first mobile service processor 110 includes a first RS frame encoder 111, a first block processor 112, a group formatting module 113, a first signaling encoder 114, A data generator 115, a position holder generator 116, and a byte-to-symbol converter 117.

The second mobile service processing unit 120 includes a second RS frame encoder 121, a second block processor 122, a segment multiplexer 123, a second signaling encoder 124, a second known data generator 125, , And a bit-to-symbol converter (127).

In the transmission system configured as described above, the first mobile service data is input to the first RS frame encoder 111 of the first mobile service processing unit 110. The first mobile service data is in the IP datagram format.

The first RS frame encoder 111 forms an RS frame payload for the first mobile service after data input of the first mobile service data, and performs coding for error correction in units of an RS frame payload Thereby forming an RS frame. The first RS frame encoder 111 may be provided in parallel with the number of parades for the first mobile service in the FC-M / H frame.

The data of the error-correction-coded RS frame is allocated to a corresponding area of a plurality of data groups. That is, the data in the error-correction-coded RS frame may be all allocated to the A / B / C / D area in the plurality of data groups, or may be allocated to the A / B area and the C / D area.

In the present invention, the RS frame data for the first mobile service is allocated to the A / B area in the plurality of data groups. In this case, the RS frame mode value becomes 01.

In order to allocate the data of the RS frame to the A / B area of the plurality of data groups, the first RS frame encoder 111 separates the error-correction-encoded RS frame into several portions. Each portion of the RS frame corresponds to an amount of data that can be transmitted by the A / B area in one data group.

13 is a detailed block diagram illustrating an embodiment of a first RS frame encoder 111 according to the present invention.

The first RS frame encoder 111 may include a data randomizer 211, an RS-CRC encoder 212, and an RS frame divider 213.

That is, the data renderer 211 of the first RS frame encoder 111 receives and renders the first mobile service data, and outputs it to the RS-CRC encoder 212.

The RS-CRC encoder 212 combines the rendered first mobile service data to form an RS frame payload, and transmits at least one of RS (Reed-Solomon) and CRC (Cyclic Redundancy Check) codes to the RS frame payload (Forward Error Correction) coding using one of them to form an RS frame, and then outputs the RS frame to the RS frame divider 213. The FEC refers to a technique for correcting an error occurring in a transmission process.

That is, the RS-CRC encoder 212 writes the first mobile service data input from the left to the right and from top to bottom so as to have the RS frame payload size for the first mobile service, 1 RS frame payload for mobile services.

And performs at least one of an error correction encoding process and an error detection encoding process in units of an RS frame payload. In this way, robustness is imparted to the first mobile service data, and a crowded error that may be caused by a radio wave environment change is reduced, so that it is possible to cope with extremely poor and rapidly changing radio wave environment.

In addition, the RS-CRC encoder 212 may combine a plurality of RS frame payloads to form a super frame, and perform row permutation on a super frame basis. The low permutation is also referred to as low interleaving. That is, when the RS-CRC encoder 212 performs a process of mixing each row of the super frame with a preset rule, the positions of the rows before and after the low-mix are different in the super frame. Even if an error that can not be corrected is contained in one RS frame to be decoded because a section in which a large number of errors occur is very long in the super-frame-by-super-frame blurring, these errors are distributed throughout the super frame, The decoding capability is improved. The low shuffling process is optional.

The RS-CRC encoder 212 applies RS coding for error correction coding and CRC (Cyclic Redundancy Check) coding for error detection coding. When the RS coding is performed, parity data to be used for error correction is generated, and CRC coding is performed to generate CRC data to be used for error detection. The CRC data generated by the CRC encoding can be used to indicate whether the first mobile service data is transmitted through the channel and is damaged by an error. The present invention may use other error detection coding methods other than CRC coding, or may increase the overall error correction capability on the receiving side by using an error correction coding method.

The RS frame payload for the first mobile service generated by the RS-CRC encoder 212 has a size of N (row) x 187 (column) bytes as shown in FIG. 14 (a) For example. N is the length of the row (i.e., the number of columns), and 187 is the length of the column (i.e., the number of rows). The RS-CRC encoder 212 performs RS coding on each column of the RS frame payload having a size of Nx187 bytes as shown in FIG. 14 (b), adds P1 pieces of parity data to each column, (c), CRC coding is performed on each row, and a 2-byte CRC checksum is added to each row to form an RS frame.

Table 2 below shows an example of the RS encoding information, that is, the RS code mode.

RS Code mode (2 bits) Description 00 (211, 187) RS code, P1 = 24 01 (223, 187) RS code, P1 = 36 10 (235, 187) RS code, P1 = 48 11 Reserved

In Table 2, two bits are allocated to indicate the RS code mode. For example, if the RS code mode value is 01, (223, 187) -RS encoding is performed on the corresponding RS frame payload, and 36 bytes of RS parity data is added for each column. That is, the RS code mode indicates the number of parity (P1) of the corresponding RS frame payload.

Here, the RS-CRC encoder 212 performs RS frame coding, RS coding, CRC coding, superframe construction, and low-frame mixing at the superframe by referring to preset transmission parameters and / or transmission parameters provided from the outside can do.

In the present invention, when the RS frame payload for the first mobile service before error correction coding has a size of Nx187 bytes as shown in FIG. 15, each of the N bytes of the N bytes is referred to as M / H service data Packet. The M / H service data packet may be composed of 2 bytes of M / H header and N-2 bytes of M / H payload. Here, the allocation of the M / H header area to 2 bytes is only one embodiment, and this can be changed by the designer, so the present invention is not limited to the above embodiment.

In this case, the first mobile service data is an IP datagram. The RS frame payload may include table information and IP datagrams for the first mobile service. For example, IP datagrams and table information of two kinds of first mobile service data, such as news (e.g., IP datagram for mobile service 1) and securities (for example, IP datagram for mobile service 2) RS frame payload.

That is, table information of a section structure may be allocated to the M / H payload in the M / H service data packet constituting the RS frame payload, or an IP datagram of the first mobile service data may be allocated.

Alternatively, the IP datagram of the table information may be allocated to the M / H payload in the M / H service data packet constituting the RS frame payload, or the IP datagram of the first mobile service data may be allocated.

At this time, it may happen that the M / H service data packet does not become N bytes including the M / H header.

In this case, a stuffing byte may be allocated to the remaining payload portion of the corresponding M / H service data packet. For example, after assigning program table information to one M / H service data packet, if the length of the M / H service data packet is N-20 bytes including the M / H header, You can allocate bytes.

16 shows an example of fields allocated to an M / H header field in an M / H service data packet according to the present invention, and may include a type_indicator field, an error_indicator field, a stuff_indicator field, and a pointer field.

The type_indicator field may allocate 3 bits in one embodiment and indicate the type of data allocated to the payload in the corresponding M / H service data packet. That is, it indicates whether the data of the M / H payload is an IP datagram or signaling information including table information. At this time, each data type constitutes one logical channel. In a logical channel transmitting an IP datagram, a plurality of mobile services are multiplexed and transmitted, and each mobile service is demultiplexed in the IP layer.

The error_indicator field may allocate 1 bit in one embodiment and indicates whether the corresponding M / H service data packet is erroneous. For example, if the value of the error_indicator field is 0, it means that there is no error in the corresponding M / H service data packet, and if it is 1, it means that there is an error.

The stuff_indicator field may allocate 1 bit in one embodiment, and indicates whether there is a stuffing byte in the payload of the corresponding M / H service data packet. For example, if the stuff_indicator field value is 0, it means that there is no stuffing byte in the corresponding M / H service data packet, and if it is 1, it means that there is a stuffing byte.

The pointer field may allocate 11 bits in one embodiment and indicate location information where new data (i.e., new signaling information or a new IP datagram) starts in the corresponding M / H service data packet.

For example, if an IP datagram for mobile service 1 and an IP datagram for mobile service 2 are allocated to the first M / H service data packet in the RS frame payload as shown in FIG. 15, Field value indicates the start position of the IP datagram for mobile service 2 in the corresponding M / H service data packet.

If there is no new data to start in the corresponding M / H service data packet, the pointer field value is displayed as a maximum value. In the present invention, 11 bits are allocated to the pointer field. Thus, if 2047 is indicated in the pointer field value, it means that there is no data to be newly started. The point indicated when the pointer field is 0 may be changed according to the type_indicator field value and the stuff_indicator field value.

The order, location, and meaning of the fields allocated to the M / H header in the M / H service data packet shown in FIG. 16 are merely examples for facilitating understanding of the present invention. The order, location, meaning, and the number of fields to which additional fields are allocated can be easily changed by those skilled in the art, so that the present invention is not limited to the above embodiments.

Meanwhile, as shown in FIG. 14 (c), the data of the RS frame in which the RS encoding and the CRC encoding are performed is output to the RS frame divider 213.

The RS frame divider 213 divides an RS frame having a size of (N + 2) x (187 + P1) into PLs (PL is the RS frame portion length) 1 block processor 112 as shown in FIG.

At this time, the PL value may be changed according to the RS frame mode, the SCCC block mode, and the SCCC outer code mode. In the present invention, the data of the RS frame for the first mobile service is allocated to the A / B area in the data group and is transmitted. Therefore, the RS frame mode should be set to 01, and the SCCC block mode should be set to 00. Therefore, the PL value is determined as shown in Table 3 below.

That is, Table 3 shows an example of the PL value of the RS frame, which varies according to the SCCC outer code mode value when the RS frame mode value is 01 and the SCCC block mode value is 00. [

                      SCCC outer code mode                      PL for Region A for Region B 00 00 7644 00 01 6423 01 00 5043 01 01 3822 Others Reserved

For example, if the SCCC outer code mode value of the A / B area is 00 each, the first mobile service data of 7644 bytes in the primary RS frame may be allocated to the A / B area of the corresponding data group.

In addition, the total number of bytes of the RS frame in which RS and CRC coding are performed is equal to or slightly smaller than 5 x NoG x PL. In this case, the RS frame is divided into ((5 x NoG) -1) pots of PL size and one pot of PL size or smaller size. That is, the size of each potion except the last potion among the potions divided from one RS frame is equal to PL.

If the size of the last portion is less than PL, stuffing bytes (or dummy bytes) are inserted into the last portion for the shortest number of bytes so that the size of the last portion is finally PL.

17A and 17B show that when dividing the RS frame of size (N + 2) x (187 + P1) into (5 x NoG) potions having a PL size, S stuffing bytes As shown in FIG.

That is, as shown in FIG. 17A, RS and CRC-encoded RS frames are divided into a plurality of potions as shown in FIG. 17B. The number of potions to be divided from the RS frame is (5 x NoG). The first ((5 x NoG) - 1) potions include the PL size, but the last one potion may be equal to or less than the PL size. If the PL is smaller than the PL size, S1 stuffing bytes can be obtained and filled in as shown in Equation (2) below so that the last portion is PL size.

Each potion including the PL size data is output to the first block processor 112.

The data of each portion output from the first RS frame encoder 111 includes at least one of pure first mobile service data, RS parity data, CRC data, and stuffing data. In a broad sense, data for the first mobile service admit. Therefore, all the data of each portion will be described as first mobile service data.

The first block processor 112 performs SCCC outlier encoding on the output of the first RS encoder 111. That is, the first block processor 112 encodes the data of each portion, which is error-correction-coded and input, into a 1 / H (H is a natural number of 2 or more) code rate and outputs the data to the group formatting unit 113. The present invention is characterized in that the input data is encoded by either encoding at 1/2 coding rate (or 1/2 coding) or encoding at 1/4 coding rate (or 1/4 coding) As an example.

The first block processor 112 may perform 1 / H encoding on a SCCC block basis. The SCCC block includes at least one M / H block.

At this time, if 1 / H encoding is performed in units of one M / H block, the M / H block and the SCCC block are the same. For example, the B1 M / H block can perform coding at a 1/2 coding rate, the B2 M / H block at a 1/4 coding rate, and the B3 M / H block at a 1/2 coding rate. The same is true for the remaining M / H blocks.

When 1 / H encoding is performed in the first block processor 112 as described above, the SCCC related information must be transmitted to the receiving system in order to accurately recover the first mobile service data.

Table 4 below shows an example of the SCCC block information, that is, the SCCC block mode.

 SCCC block mode (2 bits)              Description            00  SCCC block is identical with M / H block            01                 Reserved            10                 Reserved            11                 Reserved

In Table 4, two bits are allocated to indicate the SCCC block mode. For example, if the SCCC block mode value is '00', it indicates that the SCCC block and the M / H block are identical.

Table 5 below shows code rate information of the SCCC block, that is, an example of the SCCC outer code mode.

In Table 5, 2 bits are allocated to indicate the coding rate information of the SCCC block. For example, if the SCCC outer code mode value is 00, the code rate of the corresponding SCCC block indicates 1/2, and if it is 01, 1/4 is indicated.

If the SCCC block mode value in Table 4 indicates 00, the SCCC outer code mode can display the coding rate of each M / H block corresponding to each M / H block.

The group formatting unit 113 receives the 1 / H-encoded RS frame data from the first block processor 112 and inserts the data into the A / B area in the plurality of data groups.

The group formatting unit 113 receives the signaling data (for example, FIC data, TPC data) encoded by the first signaling encoder 114 and inserts the signaling data into the corresponding region of the data group.

The group formatting unit 113 receives the known data generated by the first known data generator 115 according to a predetermined method, and inserts the known data into a corresponding area of the data group.

In addition to the first mobile service data encoded by the first block processor 112, the group formatting unit 113 may include an MPEG header position holder, an unstructured RS parity position holder, a main service data position holder, A holder or the like is received from the first position holder generator 116 and inserted into the corresponding area of the data group.

The TPC data includes an M / H-Ensemble ID, an M / H-Subframe Number, a TNoG (Total Number of M / H-Groups), an RS frame Continuity Counter, a Column Size of RS- RS coding related information, SCCC coding related information, and FC-M / H frame related information. The TPC data is merely an example for facilitating understanding of the present invention, and addition and deletion of the signaling information included in the TPC can be easily changed by those skilled in the art, so the present invention is not limited to the above embodiments. The FIC data is provided to enable a fast service acquisition at a receiver, and includes cross-layer information between a physical layer and an upper layer.

For example, when the data group includes six known data streams as shown in FIG. 4, the signaling data stream is located between the first known data stream and the second known data stream. Therefore, the TPC data and the FIC data are inserted into the signaling information area. Also, the first known data sequence is inserted into the last two segments of the M / H block B3 in the data group, and the second known sequence data sequence is inserted into the second and third segments of the M / H block B4. And the third to sixth known data streams are inserted into the last two segments of the M / H blocks B4, B5, B6 and B7, respectively. The first, third, and sixth to sixth known data streams are separated by 16 segments.

The output of the group formatting unit 113 is byte-by-byte. The 12-way TCM is converted into a symbol unit by the byte-to-symbol converter 117 and then output to the symbol multiplexer 131.

Meanwhile, the second RS frame encoder 121 of the second mobile service processing unit 120 forms a RS frame payload for the second mobile service after data-re-inputting the input second mobile service data, And performs encoding for error correction on a load-by-load basis. The second mobile service data is in the IP datagram format. The second RS frame encoder 121 may be provided in parallel to the number of parades for the second mobile service in the FC-M / H frame.

FIG. 18 is a detailed block diagram of an embodiment of a second RS frame encoder 121 according to the present invention, and is basically the same as the first RS frame encoder 111. FIG.

The second RS frame encoder 121 may also include a data randomizer 311, an RS-CRC encoder 312, and an RS frame divider 313.

That is, the data renderer 311 of the second RS frame encoder 121 receives and renders the second mobile service data, and outputs it to the RS-CRC encoder 312.

The RS-CRC encoder 312 forms an RS frame payload for the second mobile service by gathering the second mobile service data that has been rendered, performs FEC (Forward Error Correction) coding on the formed RS frame payload, And outputs it to the RS frame divider 313. The FEC refers to a technique for correcting an error occurring in a transmission process.

That is, the RS-CRC encoder 312 writes the second mobile service data input from the left to the right and from top to bottom so as to have the RS frame payload size for the second mobile service, 2 forms an RS frame payload for the mobile service.

And performs at least one of an error correction encoding process and an error detection encoding process in units of an RS frame payload. In this way, robustness is imparted to the first mobile service data, and a crowded error that may be caused by a radio wave environment change is reduced, so that it is possible to cope with extremely poor and rapidly changing radio wave environment.

In addition, the RS-CRC encoder 312 may collect a plurality of RS frame payloads to form a super frame, and perform row permutation on a super frame basis. Even if an error that can not be corrected is contained in one RS frame to be decoded because a section in which a large number of errors occur is very long in the super-frame-by-super-frame blurring, these errors are distributed throughout the super frame, The decoding capability is improved. The low shuffling process is optional.

The RS-CRC encoder 312 applies RS coding for error correction coding and CRC (Cyclic Redundancy Check) coding for error detection coding. When the RS coding is performed, parity data to be used for error correction is generated, and CRC coding is performed to generate CRC data to be used for error detection. The CRC data generated by the CRC encoding may be used to indicate whether or not the second mobile service data is transmitted through the channel and is corrupted by an error. The present invention may use other error detection coding methods other than CRC coding, or may increase the overall error correction capability on the receiving side by using an error correction coding method.

The RS frame payload for the second mobile service generated by the RS-CRC encoder 312 has an N (row) x M (column) byte size as shown in FIG. Where N is the length of the row (i.e., the number of columns) and M is the length of the column (i.e., the number of rows). The M may be 187 or may be a value other than 187.

In addition, the RS-CRC encoder 312 RS-codes each column of the RS frame payload having the size of NxM bytes, adds P2 parity data to each column, performs CRC encoding on each row, A 2-byte CRC checksum is added to each RS frame to form an RS frame for the second mobile service.

The RS encoding information for the second mobile service, that is, the RS code mode, may be set for the RS frame for the second mobile service, as shown in Table 2 above.

Here, the RS-CRC encoder 312 refers to an RS frame configuration, a RS encoding, a CRC encoding, a super frame configuration, a super frame unit, and a super frame configuration for a second mobile service by referring to preset transmission parameters and / And the like can be performed.

Also in the RS frame payload for the second mobile service, each row of N bytes is referred to as an M / H service data packet for convenience of explanation. The M / H service data packet may be composed of 2 bytes of M / H header and N-2 bytes of M / H payload. Here, the allocation of the M / H header area to 2 bytes is only one embodiment, and this can be changed by the designer, so the present invention is not limited to the above embodiment.

The M / H header field may include a type_indicator field, an error_indicator field, a stuff_indicator field, and a pointer field.

And the second mobile service data is in the form of IP datagram. The RS frame payload may include table information and an IP datagram for the second mobile service. That is, the table information of the section structure may be allocated to the M / H payload in the M / H service data packet constituting the RS frame payload, or the IP datagram of the second mobile service data may be allocated. Alternatively, the IP datagram of the table information may be allocated to the M / H payload in the M / H service data packet constituting the RS frame payload, or the IP datagram of the second mobile service data may be allocated.

A description of each field allocated to the M / H header and a description of data allocated to the M / H payload will be omitted from FIG. 15, as described above.

On the other hand, as shown in FIG. 19, the data of the RS frame in which the RS encoding and the CRC encoding are performed is output to the RS frame divider 313.

The RS frame divider 313 divides an RS frame having a size of (N + 2) x (M + P2) bytes into a plurality of portions. That is, it is divided into a number of potions corresponding to the number of M / H subframes included in one FC-M / H frame. Therefore, in the present invention, it is divided into five potions as shown in FIG. 20 (b). And the data of each divided portion is transmitted through each M / H subframe. That is, since data of one RS frame is allocated to one FC-M / H frame, five pieces of potion data classified from the RS frame are allocated to five M / H subframes.

At this time, the size of the RS frame output from the second block processor 122 for the second mobile service is determined by the code rate of the second RS frame encoder 121 and the second block processor 122, The number of allocated segments, and the like. When dividing the RS frame by the RS frame divider 313, stuffing data of S2 bits may be added as shown in FIG. 20 (a) for equal halftoning.

That is, in (b) of FIG. 20, NoS is the number of segments assigned to the corresponding parade in one M / H subframe. And the output bit of the second RS frame encoder 121 is 5 x (NoS x 1656 (sym / seg) x 2 x CodeRate). Also, (N + 2) x (M + P2) x 8 + S2 bit_stuff is equal to 8280 x NoS x CodeRate. The S2 bit_stuff can be found by floor (8280 x NoS x CodeRate / 8 / (M + P)) - 2.

The data of each portion divided by the RS frame divider 313 is input to the second block processor 122. The second block processor 122 performs encoding using a parallel turbo code (i.e., a parallel concatenated convolutional code (PCCC)).

FIG. 21 is a detailed block diagram showing an embodiment of a second block processor 122 according to the present invention, in which a second block processor 122 and a Trellis encoder 132 are shown in a connected state. Actually, in the transmission system, a plurality of blocks exist between the second block processor 122 and the trellis encoder 132. In the receiving system, however, decoding is performed considering that two blocks are concatenated.

The second block processor 122 may include a bit-to-symbol converter 511, K interleavers 521 to 52K configured in parallel, and K + 1 convolutional encoders 530 to 53K configured in parallel. The bit-to-symbol converter 511 is optional.

That is, the second block processor 122 having the 1 / H code rate has a total of K + 1 branches including the branch or path to which the original input data is directly transferred to the convolutional encoder 530. [ K convolutional encoders 531 to 53K are connected to output ends of the K interleavers 521 to 52K, respectively. At this time, the interleavers 521 to 52K may be composed of different types of symbol interleavers. Each of the convolutional encoders may encode input data at any one of 1, 1/2, 1/3, 1/4, 1/5, and 1/6 coding rates and output the encoded data.

In the present invention, K is equal to or smaller than 12 as one embodiment. If K is 12, the output of the 12th convolutional encoder can be arranged to be input to the 12th trellis encoder of the trellis encoder 132. [ If K is 3, the output bytes of the convolutional encoder 530 are input to the first through fourth trellis coder of the trellis encoder 132, and the output bytes of the convolutional encoder 531 are input to the trellis And the output bytes of the convolutional encoder 532 are input to the 9th to 12th trellis coder of the trellis encoder 132 Can be controlled. That is, each convolutional encoder is paired with a specific trellis encoder of a legacy VSB system.

The number of trellis encoders, the number of convolutional encoders, and the number of interleavers presented in the present invention are preferred embodiments or merely examples, and the scope of the present invention is not limited to the numerical values.

At this time, the trellis encoder 132 symbolizes the input data and divides the data into the trellis coder according to a predefined scheme. Then, each trellis encoder precodes the upper bits of the input symbols and outputs them to the uppermost output bit C2, and the lower bits are Trellis-encoded to output the two output bits C1 and C0.

That is, the second mobile service data encoded with the 1 / H code rate in the second block processor 122 is output to the segment multiplexer 123. The signaling data encoded by the second signaling encoder 124 and the known data stream generated by the second known data generator 125 are also output to the segment multiplexer 123. The signaling data is composed of pre-signaling data and post signaling data, and the post signaling data is composed of FIC data and TPC data. The TPC data for the second mobile service also includes an M / H-Ensemble ID, an M / H-Subframe Number, a TNoG (Total Number of M / H-Groups), an RS frame Continuity Counter, FIC Version Number, RS encoding related information, PCCC encoding related information, and FC-M / H frame related information. The TPC data is merely an example for facilitating understanding of the present invention, and addition and deletion of signaling information included in the TPC can be easily changed by those skilled in the art, so the present invention is not limited to the above embodiments. The FIC data is provided to enable fast service acquisition in a receiving system and includes cross-layer information between a physical layer and an upper layer.

The segment multiplexer 123 allocates the second mobile service data, the signaling data, and the known data sequence to the corresponding segment of each M / H subframe in the FC-M / H frame according to the predetermined segment multiplexing rule.

11, the pre-signaling data is allocated at the head of the data area for the second mobile service in every M / H subframe, and then TPC data and FIC data are sequentially allocated. And allocates second mobile service data after the FIC data. If allocation of the second mobile service data and an area remaining in the data area for the second mobile service occurs, dummy (or stuffing) data is assigned to the area as an embodiment.

The pre-signaling data is used for detecting a training mode, that is, a length of a known data sequence for CIR estimation and an insertion period. The pre-signaling data has a two-segment length, and the training mode value is repeatedly allocated.

For example, when the training mode is composed of four bits, there is a known data sequence for a training mode having a 0.5-segment length corresponding to 0 and 1 for each bit as shown in FIG. 22 (a) A training mode is represented by a 4-bit word. At this time, the end of each known data row is patterned to be zero. By doing so, memories of the trellis encoder are initialized to zero at the end of each known data sequence for the training mode.

The meaning of the 4-bit word expressing the training mode is determined in advance by the promise of the transmitting / receiving side. For example, as shown in FIG. 9, a training mode for transmitting a known data sequence for channel equalization having two segment lengths per 16 segments or 12 segments can be defined as "1001 ". As another example, a training mode for transmitting a known data sequence for channel equalization of one segment length per 12 segments may be defined as "0011 ".

Assuming that the training mode value is "1001 ", the known data sequences of the Seq # 2 Seq # 3 Seq # 5 Seq # 8 pattern are combined to construct a known data sequence for the training mode of 2 segments long , And is allocated to the pre-signaling data area in the M / H sub-frame. That is, the pre-signaling data allocated to the two-segment pre-signaling data area is a pattern in which the pattern of Seq # 2 Seq # 3 Seq # 5 Seq # 8 Seq # 2 Seq # 3 Seq # 5 Seq # 8 is repeated.

As another example, assuming that the training mode value is "0011 ", the known data sequences of the Seq # 1 Seq # 3 Seq # 6 Seq # 8 pattern are combined to constitute a base data sequence for the training mode of two segments length And is allocated to the pre-signaling data area in the M / H sub-frame. That is, the pre-signaling data allocated to the two-segment pre-signaling data area is a pattern in which the pattern Seq # 1 Seq # 3 Seq # 6 Seq # 8 Seq # 1 Seq # 3 Seq # 6 Seq # 8 is repeated.

At this time, the patterns of at least two known data sequences among the known data streams of the Seq # 1 to Seq # 8 patterns are different from one another. It is also assumed that the pattern of each known data sequence is a pattern previously known by an appointment in the transmitting / receiving system.

Therefore, the receiving system can determine the training mode by determining how the pre-signaling data received in the pre-signaling data area is a combined pattern. Knowing the training mode value, the length and the insertion period of the known data sequence transmitted for CIR estimation can be known.

Since the pre-signaling data is always inserted in the M / H subframe after the known data sequence for CIR estimation, it is not necessary to initialize the memory of the trellis encoder. In other words, it is not necessary to initialize the memory of the separate trellis encoder for generating the known data sequence after the trellis coding.

At the end of the pre-signaling data, all the memories of the trellis encoder become zero according to the characteristics of the pattern itself. That is, by patterning the end of the pre-signaling data to zero, all memories of the trellis encoder are zeroed at the end of the pre-signaling data according to the characteristics of the pattern itself without any apparent trellis state termination.

The pre-signaling data may be used for frame acquisition since the pre-signaling data is a combination of patterns already known in the receiving system. Or, the pre-signaling data may be used for carrier recovery by estimating a frequency offset.

23 is a diagram showing an example of allocating signaling data in a data area for a second mobile service in an M / H subframe.

The post signaling data is composed of TPC data and FIC data, and the TPC data is again composed of common-TPC data and parade-TPC data.

The common-TPC data includes transmission parameters commonly applied to the paradises of all second mobile services.

The common-TPC data has a fixed length of two segments as shown in FIG. 23, and is allocated after the pre-signaling data. The last 24 symbols of the common-TPC data are used for initializing the trellis encoder.

The parade-TPC data and the FIC data may have different lengths in FC-M / H frames and the coding rates may be different. Information about this is included in the common-TPC data and transmitted. However, one M / H subframe in one FC-M / H frame has the same length and coding rate. The Parade-TPC data transmits the information of the individual parade of the second mobile service. In the case where a known data sequence or training signal for CIR estimation is inserted in the middle of the parade-TPC data, the PCCC block of the parade-TPC data includes a parity- It is divided by known data stream.

For example, when the length of the parade-TPC data is 8 or more segments and the first mobile service exists in the M / H subframe, the PCCC block of the parade-TPC data is divided based on the known data sequence. 23 shows an example in which the PCCC block of the parade-TPC data is divided into BL1 and BL2 based on the known data sequence.

When the memory of the trellis encoder is terminated at the end of the Common-TPC data and at the end of the known data string and the memory of the PCCC encoder is set to zero at the beginning of the parade-TPC data block, the start state of each block is always It becomes zero. FIC data is allocated after the parade-TPC data. The FIC data may be different between M / H subframes in one FC-M / H frame. That is, the FIC data can transmit different contents for each M / H subframe.

24 is a detailed block diagram of an embodiment of a second signaling encoder 124 for a second mobile service according to the present invention.

The second signaling encoder 124 of FIG. 24 comprises two paths, a path for encoding TPC data and a path for encoding FIC data.

The path for coding the TPC data may include a randomizer 611, an RS encoder 612, a block interleaver 613, a byte-to-bit converter 614, and a PCCC encoder 616. Bit converter 614 and the PCCC encoder 616. The bit-to-bit converter 614 and the PCCC encoder 616 may be connected to the known data inserter 615. [ The known data inserter 615 may be used to rob TPC data more error-prone, and its use is optional. In other words, if known bit data bits are inserted according to the promise of the transmitting / receiving system, the receiving system can know what bit is inserted at which position of the TPC data, thereby improving the receiving performance of the receiving system .

That is, the TPC data is input to the renderer 611 and rendered, and then input to the RS encoder 612 and RS-encoded. The common-TPC data of the RS-coded TPC data is output to the byte-to-bit converter 614. The parade-TPC data is interleaved in the block interleaver 613 and then output to the byte-to-bit converter 614, . Bit TPC data output from the byte-to-bit converter 614 is input to the PCCC encoder 616, encoded by the PCCC method, and then output to the segment multiplexer 123. In this case, both the Common-TPC data and the Parade-TPC data may be input to the known data inserter 615 in some cases, and the known data bits may be inserted in the middle, to implement the code rate. For example, if one known data bit is inserted for every four bits and the 1/4 PCCC encoding is performed in the PCCC encoder 6116, the result is encoded at a 1/5 code rate.

The path for FIC data encoding may include a renderer 621, an RS encoder 622, a byte-to-bit converter 623, and a PCCC encoder 624.

That is, the FIC data is input to the Renderer 621, rendered by the Renderer 621, input to the RS encoder 622, and RS-encoded. The RS encoded FIC data is output to the byte-to-bit converter 623, converted into bits, input to the PCCC encoder 624, encoded in PCCC format, and then output to the segment multiplexer 123. The segment multiplexer 123 multiplexes the RS frame data encoded in the second block processor 122, the signaling data encoded in the second signaling encoder 124, and the known data generated in the known data generator 125 And outputs the multiplexed signal according to a predetermined segment multiplexing rule. For example, the segment multiplexer 123 outputs a 2-segment known data sequence, then outputs 2-segment length pre-signaling data, and outputs the common-TPC data, parade- Data and FIC data sequentially, and then outputs the data of the RS frame. The data multiplexed and output by the segment multiplexer 123 is converted into a symbol unit by the bit-to-symbol converter 127 and output to the symbol multiplexer 131.

The symbol multiplexer 131 receives symbol-by-symbol data for the first mobile service from the byte-to-symbol converter 117 and receives symbol-by-symbol data for the second mobile service from the bit- And outputs the multiplexed signal according to a predetermined symbol multiplexing rule. For example, if data for the first mobile service and data for the second mobile service are transmitted together in the first M / H slot in the M / H subframe, then the first mobile during the 96th segment of the first M / Outputs the data symbols for the service, and then outputs the data symbols for the second mobile service for the 60 segments.

The output of the symbol multiplexer 131 is input to the trellis encoder 132. The trellis encoder 132 performs 12-way interleaving on the data input on a symbol-by-symbol basis and performs trellis encoding on the data, and outputs the data to the synchronous multiplexer 133. The trellis encoder 132 operates in the same manner as the existing VSB system and performs memory initialization according to input data.

The synchronous multiplexer 133 inserts field synchronization and segment synchronization into the output of the trellis encoder 132 and outputs it to the pilot inserter 134.

The pilot inserted data in the pilot inserter 134 is modulated by a modulator 135 in a predetermined modulation scheme, for example, a VSB scheme, and then transmitted to each reception system via an RF up-converter 136.

In the receiving system Demodulator

25 is a block diagram showing an embodiment of a demodulation unit in a reception system according to the present invention. In the demodulation unit of FIG. 25, the reception performance can be improved by receiving the known data, signaling data, and the like transmitted from the transmission system and using it for carrier recovery, timing recovery, frame synchronization recovery, and channel equalization.

The demodulator according to the present invention includes a demodulator 711, an equalizer 712, a block decoder 713, an RS frame decoder 714, a pre-signaling decoder 721, a training signal detector 722 and a post- (723).

That is, the broadcast signal of the specific channel tuned through the tuner is down-converted to an intermediate frequency (IF) signal, and the down-converted signal is output to the demodulator 711 and the pre-signaling decoder 721. At this time, the down-converted signal is input to a demodulator 711 and a pre-signaling decoder 721 through an analog / digital converter (ADC) (not shown) for converting an analog IF signal of a pass band into a digital IF signal As an embodiment.

The broadcast signal received by the tuner may include only data for the second mobile service, or may include all data for the first and second mobile services. That is, only data for the second mobile service may be received in units of FC-M / H frames, and data for the first and second mobile services may all be received.

The data for the first mobile service includes first mobile service data, known data for the first mobile service, TPC data, and FIC data.

The data for the second mobile service includes a second mobile service data, a known data sequence (or a training signal) for CIR estimation of the second mobile service, pre-signaling data, and post signaling data. The post signaling data includes TPC data and FIC data.

The demodulator 711 performs automatic gain control, carrier recovery, and timing recovery on a digital IF signal of an input passband to generate a baseband signal, and then generates an equalizer 712, a pre-signaling decoder 721, And outputs it to the signal detector 722. The demodulator 711 demodulates the pre-signaling data decoded by the pre-signaling decoder 721 and the training signal detected by the training signal detector 722, for example, when performing automatic gain control, carrier recovery, and timing recovery, By using the known data, demodulation performance can be improved.

The equalizer 712 compensates for the distortion on the channel included in the demodulated signal, and outputs the compensated signal to the block decoder 713 and the post signaling decoder 723. [ The equalizer 712 uses the pre-signaling data decoded by the pre-signaling decoder 721 and the known data detected by the training signal detector 722 to compensate for the distortion on the channel included in the demodulated signal, Channel equalization performance can be improved. For example, the equalizer 712 estimates a channel impulse response (CIR) to perform channel equalization. The present invention can more reliably perform channel equalization by estimating the CIR using known data and / or field synchronization known to the location and contents by the promise of the transmitting / receiving side.

When the input data is data for the first mobile service, the equalizer 712 may use one of the CIRs estimated in the known data interval as it is according to the characteristics of each region of the data group, Or CIR generated by extrapolation may be used.

When the input data is data for the second mobile service, the equalizer 712 may use one of the CIRs estimated in the known data interval as it is, interpolates at least a plurality of CIRs, Extrapolation is used to generate the CIR.

Here, interpolation is a function value at a certain point between Q and S when a function value F (Q) at a point Q and a function value F (S) at a point S are known for a certain function F (x) And the most simple example of the interpolation is linear interpolation. The linear interpolation technique is the simplest example of a number of interpolation techniques, and various other interpolation techniques may be used in addition to the above-mentioned method. Therefore, the present invention is not limited to the above example.

Also, extrapolation is a process that determines the function value F (Q) at time Q and the function value F (S) at time S for a certain function F (x) It means to estimate the function value at the time point. The simplest example of such extrapolation is linear extrapolation. The linear extrapolation technique is the simplest example of a number of extrapolation techniques, and various extrapolation techniques can be used in addition to the above-described method, so that the present invention is not limited to the above example.

The pre-signaling decoder 721 receives at least one of the pre / post signals of the demodulator 711 and is allocated in front of the data area for the second mobile service in each M / H subframe in the FC-M / H frame And decodes the received pre-signaling data. For example, the pre-signaling decoder 721 estimates a training mode by determining a combination of known patterns of pre-signaling data. And decodes the length of the known data and the insertion period for the second mobile service according to the estimated training mode. The known pattern constituting the pre-signaling data can be used to correct frame acquisition and frequency offset.

The decoded pre-signaling data is output to a demodulator 711, an equalizer 712, a training signal detector 722, and a post signaling decoder 723.

The training signal detector 722 detects the known data information known by the promise of the transmitting / receiving side from the demodulation pre / post signal and outputs it to the demodulator 711 and the equalizer 712. If the known data is the known data for the second mobile service, the training signal detector 722 refers to the pre-signaling data decoded by the pre-signaling decoder 721, i.e., Data information can be detected.

The demodulator 711 uses the output of the training signal detector 722 if the user has selected the first mobile service and the pre-signaling data decoded by the pre-signaling decoder 721 if the user selects the second mobile service And performs timing recovery, carrier recovery, and the like on the digital IF signal of the pass band to be input.

The post signaling decoder 723 uses the signal with the channel distortion compensated by the equalizer 712 and the training mode input from the pre-signaling decoder 721 (i.e., the length of the known data sequence and the insertion period) Decodes the common / TPC data, parade-TPC data, FIC data, and the like to demodulator 711, block decoder 713, and RS frame decoder 714. The demodulator 711 can determine the frame structure using the TPC data of the decoded post signaling data.

The post-signaling decoder 723 decodes the post-signaling data according to the PCCC scheme. For example, if the user selects the first mobile service, the TPC data, the FIC data, and the like are decoded by performing a reverse process of the first signaling encoder of FIG. If the second mobile service is selected, PCCC decoding is performed in the reverse procedure of FIG. 24 to decode common / TPC data, parade-TPC data, FIC data, etc., allocated and received after the pre-signaling data.

The decrypted common-TPC data includes transmission parameters commonly applied to all parades of the second mobile service. The parade-TPC data and the FIC data may have different lengths in FC-M / H frames and the coding rates may be different. Information about this can be found by parsing common-TPC data. The decoded Parade-TPC data includes information of individual parades of the second mobile service.

The block decoder 713 can use the decoded TPC data to distinguish whether data input from the equalizer 712 is data for a first mobile service or data for a second mobile service.

If the user selects the first mobile service, the block decoder 713 decodes the data for the first mobile service from the data output from the equalizer 712 based on the turbo decoding related information in the decoded TPC data And performs turbo decoding of the SCCC scheme in the reverse process of the transmission system. In this case, the data output from the block decoder 713 may include RS frame data of the parade of the first mobile service to be received (i.e., first mobile service data inserted in the corresponding RS frame payload, RS parity, and CRC data). That is, the block decoder 713 performs trellis decoding and SCCC type block decoding on the data for the first mobile service, inversely to the transmitting side. At this time, the first block processor 112 on the transmission side can be regarded as an external encoder, and the trellis encoder 132 can be regarded as an internal encoder. In order to maximize the decoding performance of the outer code in decoding the concatenated code, it is preferable to output the soft decision value in the decoder of the inner code.

On the other hand, if the user selects the second mobile service, the block decoder 713 extracts data for the second mobile service from the data output from the equalizer 712, based on the turbo decoding related information in the decoded TPC data And performs PCCC turbo decoding as an inverse process of the transmission system. At this time, the data output from the block decoder 713 may include RS frame data of the parade of the second mobile service to be received (i.e., second mobile service data inserted in the corresponding RS frame payload, RS parity, and CRC data). That is, the block decoder 713 performs trellis decoding and PCCC type block decoding inversely to the transmitting side. At this time, the second block processor 122 on the transmission side can be regarded as an external encoder, and the trellis encoder 132 can be regarded as an internal encoder. In order to maximize the decoding performance of the outer code in decoding the concatenated code, it is preferable to output the soft decision value in the decoder of the inner code.

The turbo decoded data in the block decoder 713 is input to the RS frame decoder 714.

If the turbo decoded data is the data for the first mobile service, the RS frame decoder 714 refers to the RS frame related information included in the TPC data of the first mobile service, Performs an inverse procedure to correct errors generated in the first mobile service data received in the RS frame payload.

If the turbo decoded data is the data for the second mobile service, the RS frame decoder 714 refers to the RS frame related information included in the TPC data of the second mobile service, To correct errors generated in the second mobile service data received in the RS frame payload. For example, if the turbo decoded data is the data for the second mobile service, the RS frame decoder 714 decodes the RS frame based on the RS frame related information among the TPC data decoded by the post signaling decoder 723, The data for the second mobile service, which is turbo decoded and output in the block decoder 713, is collected during one FC-M / H frame, and then the CRC check and the laser RS decoding are performed. By doing so, the RS frame decoder 714 finally outputs the error-corrected second mobile service data.

In the present invention, the error-corrected second mobile service data is an IP datagram.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, .

Claims (10)

Processing packets including broadcast service data for a broadcast service;
Encoding the broadcast service data included in the processed packets at a specific code rate;
Rendering signaling data for signaling the broadcast service data;
Encoding the randomized signaling data; And
Mapping the encoded broadcast service data and the encoded signaling data to a frame and transmitting the frame;
Wherein each of the packets comprises a header and a payload, the header includes stuffing indication information indicating whether stuffing data is included in the packet, the payload including the broadcast service data,
Wherein the frame is divided into a signaling region including the coded signaling data and a data region including the broadcast service data,
Wherein the signaling region is located in front of the data region,
Wherein the signaling data comprises first signaling data and second signaling data,
The length of the first signaling data is fixed, the length of the second signaling data is variable,
Wherein the first signaling data includes information for identifying a length of the second signaling data,
Wherein the second signaling data includes code rate information of the broadcast service data. The method according to claim 1,
Wherein the broadcast service data is divided into a first type broadcast service data and a second type broadcast service data according to a mapping method. 3. The method of claim 2,
Wherein the broadcast service data of the first type is first mapped to the data area, and then the broadcast service data of the second type is mapped to the data area. delete delete A data processor for processing packets including broadcast service data for a broadcast service;
A first coder for coding the broadcast service data included in the processed packets at a specific code rate;
A randomizer for randomizing signaling data for signaling the broadcast service data;
A second encoder for encoding the rendered signaling data; And
And a transmitter for mapping the encoded broadcast service data and the encoded signaling data to a frame for transmission,
Wherein each of the packets comprises a header and a payload, the header includes stuffing indication information indicating whether stuffing data is included in the packet, the payload including the broadcast service data,
Wherein the frame is divided into a signaling region including the coded signaling data and a data region including the broadcast service data,
Wherein the signaling region is located in front of the data region,
Wherein the signaling data comprises first signaling data and second signaling data,
The length of the first signaling data is fixed, the length of the second signaling data is variable,
Wherein the first signaling data includes information for identifying a length of the second signaling data,
Wherein the second signaling data includes code rate information of the broadcast service data. The method according to claim 6,
Wherein the broadcast service data is divided into a first type broadcast service data and a second type broadcast service data according to a mapping method. 8. The method of claim 7,
Wherein the broadcast service data of the first type is first mapped to the data area, and then the broadcast service data of the second type is mapped to the data area. delete delete

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