KR20090097611A - Apparatus and method for inserting/detecting transmitter information in digital broadcasting system - Google Patents

Abstract

An apparatus for inserting/detecting transmitter information in a digital broadcasting system and a method thereof are provided to extract and collect transmitter information which can be received within a service area from a single frequency network service area. An apparatus for inserting/detecting transmitter information in a digital broadcasting system comprises a field sync generating unit(101), a transmitter identification information generating unit(103), a transmitter identification information combining unit(105) and a multiplexer. The field sync generating unit produces a field synchronization signal. The transmitter identification information generating unit produces transmitter identification information(TXID) which is the intrinsic information of a transmitter. The transmitter identification information combining unit inserts the transmitter identification information into the field synchronization signal.

Description

Apparatus and method for inserting / detecting transmitter information in a digital broadcasting system {APPARATUS AND METHOD FOR INSERTING / DETECTING TRANSMITTER INFORMATION IN DIGITAL BROADCASTING SYSTEM}

The present invention relates to an apparatus and method for inserting / detecting transmitter information in a digital broadcasting system. More particularly, the present invention relates to more efficiently extracting transmitter information that can be received in a service area to provide a satisfactory performance in a single frequency network service area. An apparatus and method for inserting / detecting transmitter information in a digital broadcasting system for collecting.

Recently developed digital broadcasting technology provides various information forms such as video, voice, sound, text, graphics, etc., and is a breakthrough technology that can provide high quality service through various media such as TV receiver, computer monitor and PDA. In particular, technologies for high quality digital TV signal transmission using a network composed of multiple transmitters have been actively studied. There are two methods of composing a network using multiple transmitters, a multiple frequency network (MFN) method and a single frequency network (SFN) method. The formed single frequency network method is more efficient in terms of frequency use than the multiple frequency network method.

That is, the digital broadcasting system uses a single frequency network to improve the efficiency of frequency use and to receive digital broadcasting in a mobile and indoor multipath environment, but has a disadvantage of being interfered by signals from neighboring transmitters. have. TXID (Transmitter Identification) technology is emerging as one of the ways to solve this problem. The TXID technology uses a low amplitude value for watermarking a spreading code, which is a pseudo noise sequence (PN), for each transmitter in the transmission data stream of each transmitter that is considered for distributed transmission. The transmitter recovers the spreading code of the transmitting end through auto-correlation operation using the sequential device and discriminates the transmitter using the restored spreading code. This transmitter identification technology uses a long spreading code with a spreading factor of tens of thousands of chips in the data field for each transmitter or repeater so that the receiver performs watermarking at a low power value that does not affect broadcast data demodulation. At the receiving end, the transmitter performs identification using a correlation value of a fairly long period, and acquires additional information accordingly.

However, this transmitter identification technique takes a long time to derive the correlation characteristics of the receiver for a very long period, and there is a problem in configuring the hardware for real-time correlation processing for system commercialization.

In addition, the single frequency network scheme has a disadvantage in that reception equalization performance is degraded due to strong (0 dB) pre / post ghost and ghost channel delay spreads caused by multiple transmitters. As a result, a wider service area can be formed by using a high performance channel equalizer. In addition, by providing a certain level of signal-to-noise ratio (SNR) in a wide coverage area including a shaded area, it is possible to provide high quality digital TV service anytime and anywhere.

However, considering the commercially available 8-VSB (8-VSGI) digital TV receiver chip and the developed range of ghost cancellation and dynamic ghost size of the equalizer, the single frequency network service area It does not always guarantee acceptable signal-to-noise ratio (SNR) and performance within.

In order to solve this problem, after estimating the information (TXID (Transmitter Identification), transmitter power (transmitter power, etc.) of each transmitter from the signal received in each service area, the transmission time of the corresponding transmitter (Transmission) time-offset) and how to adjust the size.

For example, a method of estimating information of a transmitter from a signal received in a single frequency network service area is an RF watermark technique (A / 110). RF-Watermarks (RF-Watermarks) technique, as described above, adds a low power two-level Pseudo-Random Sequence according to the WBR (Watermark Bury Ratio) to the existing A / 53 8-level residual sideband signal. send.

At this time, in order to estimate the transmitter information from the received signal, the transmitter information is estimated by using a correlation power obtained by taking a correlation between the transmitter-specific identification code stored in the receiver and the received signal and the unique identification code used. .

However, since RF-watermarks estimate the transmitter information by using correlation of identification codes, degradation of detection performance may occur due to relatively large in-band 8 level signal. have. In addition, in order to obtain accurate transmitter information required, a large amount of two-level identification codes must be received and processed, which is a problem that becomes more severe when measuring a plurality of transmitter information.

Accordingly, there is a need for a transmitter information detection technique for efficient transmitter information estimation in a short time.

The present invention has been made to improve the above-described prior art, and an object thereof is to provide an apparatus and method for inserting / detecting transmitter information in a digital broadcasting system.

Another object of the present invention is to provide an apparatus and method for inserting / detecting transmitter information in a digital broadcasting system for extracting and collecting transmitter information receivable in a service area in a single frequency network service area.

Another object of the present invention is to provide an apparatus and method for inserting / detecting transmitter information in a digital broadcasting system for extracting and collecting transmitter information receivable in a service area in a single frequency network service area.

The object of the present invention is not limited to the above-mentioned objects, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

The present invention relates to an apparatus and method for inserting / detecting transmitter information in a digital broadcasting system. In particular, the present invention relates to extracting and collecting transmitter information receivable in a service area in order to always provide satisfactory performance in a single frequency network service area. An apparatus and method for inserting / detecting transmitter information in a digital broadcasting system are disclosed.

According to a first aspect of the present invention for achieving the above objects, an apparatus for inserting transmitter information in a digital broadcasting system comprises: a field sync generator for generating a field sync signal; A transmitter identification information generation unit generating transmitter identification information TXID which is information unique to the transmitter; A transmitter identification information combining unit which inserts the transmitter identification information into the field synchronization signal; And a multiplexer for generating a data frame including the field synchronization signal into which the transmitter identification information is inserted.

According to a second aspect of the present invention for achieving the above objects, an apparatus for detecting transmitter information in a digital broadcasting system includes: a transmitter identification information detecting unit for detecting transmitter identification information in a field synchronization signal of a data frame to be received; A transmitter identification information providing unit providing preset transmitter identification information of each transmitter; And a correlator performing a correlation operation on the detected transmitter identification information and the provided transmitter identification information and outputting a result.

According to a third aspect of the present invention for achieving the above objects, a method of inserting transmitter information in a digital broadcasting system is to generate a field synchronization signal and transmitter identification information (TXID) when detecting the occurrence of a transmission event of data. step; Inserting the transmitter identification information into a reserved area of the field sync signal; And generating a data frame including the field synchronization signal into which the transmitter identification information is inserted.

According to a fourth aspect of the present invention for achieving the above objects, a method for detecting transmitter information in a digital broadcasting system comprises: receiving a data frame; Detecting transmitter identification information from a field synchronization signal of the data frame; Providing preset transmitter identification information of each transmitter; And detecting transmitter information based on the detected transmitter identification information and the received transmitter identification information.

Specific details of other embodiments are included in the detailed description and the accompanying drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only the present embodiments to make the disclosure of the present invention complete, and common knowledge in the art to which the present invention pertains. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

The present invention provides a transmitter identification information detecting unit for detecting transmitter identification information from a field synchronization signal of a received data frame; A transmitter identification information providing unit providing preset transmitter identification information of each transmitter; And a correlator for performing a correlation operation on the detected transmitter identification information and the provided transmitter identification information and outputting a result thereof, the apparatus and method for detecting transmitter information in a digital broadcasting system. Since the information is watermarked and not received, the noise is low and the retrieval of transmitter identification information has an excellent effect.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention; If it is determined that the gist of the present invention may be unnecessarily obscured, detailed description thereof will be omitted.

The present invention relates to an apparatus and method for detecting transmitter information in a digital broadcasting system in which transmitter identification information is easily detected in a receiver by inserting and transmitting transmitter identification information in a field sync signal region of a data frame in a transmitter of a digital broadcasting system. The structure of the transmitter of the present invention will be described below with reference to FIG. 1.

1 is a diagram illustrating a structure of a transmitter in a digital broadcasting system according to an embodiment of the present invention. Referring to FIG. 1, the transmitter of the present invention includes a field sync generator 101, a transmitter identification information (TXID) generator 103, a transmitter identification information (TXID) combiner 105, and a multiplexer (MUX) ( 107, a pilot inserting unit 109, a modulator 111, and a frequency up-conversion unit 113.

The field sync generator 101 generates a field sync signal, which is a field header part of the frame, and provides the field sync signal to the TXID combiner 105. The TXID generation unit 103 generates the transmitter identification information TXID according to a preset method and provides the TXID combining unit 105 to the TXID combining unit 105. (For example, the TXID using the same Kasami Code generator as the ATSC A / 111 standard. Creates.)

Then, the TXID combiner 105 inserts the TXID generated by the TXID generator 103 into the reserved area of the field sync signal generated by the field sync generator 101 and provides it to the multiplexer 107. do.

The multiplexer 107 combines the symbol data, the segment synchronizing signal, and the field synchronizing signal including the TXID to generate a Vestigial Side Band (VSB) data frame and transmits it to the pilot inserting unit 109. The form of the VSB data frame will be described later with reference to FIG. 2 below.

The pilot inserter 109 inserts a pilot signal for frequency and time synchronization into a symbol signal of a VSB data frame received from the multiplexer 107 and provides the pilot signal to the modulator 111.

The modulator 111 modulates the signal into which the pilot signal received from the pilot inserter 109 is inserted into a VSB signal, and the frequency up-converter 113 converts the VSB modulated signal into an RF signal and transmits the signal.

2 is a diagram illustrating a structure of a data frame transmitted from a transmitter according to an embodiment of the present invention.

FIG. 2 illustrates a VSB data frame into which a segment synchronization signal and a field synchronization signal are inserted in a digital broadcasting system for 8-VSB. As shown, one frame is composed of two fields and one field is composed of one field sync signal 220, 240 and 312 data segments, which are the first segments. In addition, one segment corresponds to one MPEG-2 packet in a VSB data frame, and one segment includes four symbol segment sync 210 and 828 data symbols 230 and 240. .

In FIG. 2, the segment synchronization signal 210 and the field synchronization signals 220 and 240 which are synchronization signals are used for synchronization and equalization at the digital broadcast receiver. That is, the field synchronizing signal and the segment synchronizing signal are data already known between the digital broadcast transmitter and the receiver and used as reference signals when performing equalization at the receiver side.

In addition, according to the present invention, the reserved area of the field sync signals 220 and 240 includes the TXID generated by the TXID generator 103. Then, the configuration of the field sync signals 220 and 240 according to the present invention will be described below with reference to FIG. 3.

3 is a diagram illustrating a configuration of a field synchronization signal in a data frame transmitted by a transmitter according to an embodiment of the present invention. Referring to FIG. 3, the synchronization signal 301, the PN511 303, the PN63 305, 307, and 309, the VSB Mode 311, the PN Sync 313, the TXID 315, and the Precode 317 are described. Include.

Here, Sync 301 is a reference signal for time synchronization of a signal received with a receiver, PN511 303 and PN63 305, 307, and 309 are PN reference signals for driving a receiver equalizer, and VSB Mode 311. Is information on the type of VSB indicating whether it is an 8VSB or 16VSB signal, and Precode 317 is the last 12 symbols of all segments.

The remaining components except for the PN Sync 313 and the TXID 315 in the field synchronization signal are standard technologies known in the ATSC A / 111 standard, and thus will not be described in detail.

Then, the PN Sync 313 added to the reserved area according to the present invention is a starting point indication and time synchronization reference signal of the Truncated PN sequence 315, and the TXID PN Sequence 315 is a transmitter identification information (TXID) signal. As the size increases, the signal detection accuracy of the TXID increases.

4 is a diagram illustrating a structure of a receiver in a digital broadcasting system according to an embodiment of the present invention.

Referring to FIG. 4, the receiver of the present invention includes a tuner 401, an IF filter 403, a synchronization signal detector 405, a synchronizer 407, an NTSC cancellation filter 409, and a transmitter identification information (TXID) detector ( 411, a transmitter identification information (TXID) providing unit 413, a correlator 415, and a storage unit 417.

Here, the tuner 401 selects a desired channel frequency from the received signal and then transitions the VSB signal of the radio frequency band carried on the channel frequency to a fixed intermediate frequency (IF) band, and an IF (Intermediate Frequency) filter. 403 filters only a desired band of the received signal converted into IF, and the synchronization signal detector 405 detects a synchronization signal necessary for frequency / time synchronization based on the filtered signal, and the detected synchronization signal is synchronized with the synchronization unit 407. The VSB data frame provided by the RN and the synchronous signal is removed is transmitted to the NTSC cancellation filter 409.

The synchronization unit 407 synchronizes the frequency / time reference of the receiver with the received signal by using the transmitted synchronization signal, and the NTSC cancellation filter 409 receives NTSC signals that may be weakly received in the received VSB data frame. It removes and transmits it to the transmitter identification information (TXID) detection part 411. At this time, the configuration of the NTSC removal filter 409 can be operated without the optional (Optional).

Then, according to the present invention, the transmitter identification information (TXID) detection unit 411 checks PN Sync, which is the starting point of the TXID in the VSB data frame, detects the transmitter identification information (TXID) and transmits it to the correlator 415, and identifies the transmitter. The information (TXID) providing unit 413 generates a unique TXID of the transmitters according to a preset transmitter identification information (TXID) generation rule, or retrieves the stored TXIDs of the transmitters and transmits them to the correlator 415.

The correlator 415 calculates and outputs a correlation between the transmitter identification information TXID received from the TXID detector 411 and the transmitter identification information TXID received from the TXID provider 413.

The storage unit 417 stores the correlation calculation result of the correlator 415 and then provides the transmission time-offset and the size of the transmitter to adjust the setting.

Hereinafter, a transmitter information detection method for detecting transmitter identification information in a field sync signal region of a data frame according to the present invention configured as described above will be described with reference to the drawings.

5 is a flowchart illustrating a process of generating and transmitting a data frame including transmitter identification information in a field sync signal region in a transmitter according to an embodiment of the present invention.

Referring to FIG. 5, when the transmitter of the present invention detects the occurrence of a data transmission event in step 501, the transmitter proceeds to step 503 to generate a field sync signal and transmitter identification information (TXID). In step 507, the TXID is inserted into the reserved area, the data frame including the TXID is generated in the field synchronization signal. In step 509, the pilot symbol is inserted into the data frame. The signal is modulated into a residual side band (VSB) signal, and the process proceeds to step 513 to be transmitted to the receiver.

6 is a flowchart illustrating a process of identifying a transmitter by detecting transmitter identification information in a field sync signal region of a data frame in a receiver according to an embodiment of the present invention.

Referring to FIG. 6, when the receiver of the present invention receives a signal in step 601, the receiver proceeds to step 603 to transition the received signal to an intermediate frequency (IF) band and detects a data frame that is a signal of a desired band. In step 605, the synchronization signal required for frequency / time synchronization is detected from the received signal, and the frequency / time reference of the receiver is synchronized with the received signal. In step 607, the NTSC signal that can be weakly received in the data frame is performed. In step 609, the transmitter identification information (TXID) is detected in the field sync signal region of the data frame. In step 611, the transmitter identification information (TXID) generated by the storage or preset method is received. Perform the correlation operation on the transmitter identification information (TXID), go to step 613 to store the correlation operation result and use the result. It controls the set such as the transfer time (Transmission time-offset) and the amount of wear.

While specific embodiments of the present invention have been described so far, various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the claims below, but also by the equivalents of the claims.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above-described embodiments, which can be variously modified and modified by those skilled in the art to which the present invention pertains. Modifications are possible. Accordingly, the spirit of the present invention should be understood only by the claims set forth below, and all equivalent or equivalent modifications thereof will belong to the scope of the present invention.

1 is a diagram illustrating a structure of a transmitter in a digital broadcasting system according to an embodiment of the present invention;

2 is a diagram illustrating a structure of a data frame transmitted by a transmitter according to an embodiment of the present invention;

3 is a diagram illustrating a configuration of a field sync signal in a data frame transmitted by a transmitter according to an embodiment of the present invention;

4 is a diagram illustrating the structure of a receiver in a digital broadcasting system according to an embodiment of the present invention;

5 is a flowchart illustrating a process of generating and transmitting a data frame including transmitter identification information in a field sync signal region in a transmitter according to an embodiment of the present invention;

6 is a flowchart illustrating a process of identifying a transmitter by detecting transmitter identification information in a field sync signal region of a data frame in a receiver according to an embodiment of the present invention.

Claims (17)

A field sync generator for generating a field sync signal; A transmitter identification information generation unit generating transmitter identification information TXID which is information unique to the transmitter; A transmitter identification information combining unit which inserts the transmitter identification information into the field synchronization signal; And And a multiplexer for generating a data frame including the field synchronization signal into which the transmitter identification information is inserted. The method of claim 1, wherein the transmitter identification information combining unit, And inserting transmitter information into the field synchronization signal and inserting a start reference signal (PN Sync) informing that the transmitter identification information has been inserted before the transmitter identification information. Device. The method of claim 1, wherein the transmitter identification information combining unit, And inserting the transmitter identification information into the reserved area of the field synchronization signal. A transmitter identification information detector for detecting transmitter identification information from a field synchronization signal of a received data frame; A transmitter identification information providing unit providing preset transmitter identification information of each transmitter; And And a correlator configured to perform a correlation operation between the detected transmitter identification information and the provided transmitter identification information and output a result thereof. The method of claim 4, wherein the transmitter identification information detection unit, And detecting the transmitter identification information inserted into the reserved area of the field synchronization signal. The method of claim 4, wherein the transmitter identification information detection unit, And detecting the inserted transmitter identification information by using a start reference signal (PN Sync) indicating that the transmitter identification information has been inserted later in the field synchronization signal. The method of claim 4, wherein the transmitter identification information providing unit, And storing and providing the preset transmitter identification information. The method of claim 4, wherein the transmitter identification information providing unit, And transmitting the preset transmitter identification information in a predetermined manner to provide transmitter information. Generating a field sync signal and transmitter identification information (TXID) when a transmission event of data is detected; Inserting the transmitter identification information into the field synchronization signal; And And generating a data frame including the field synchronization signal into which the transmitter identification information is inserted. The method of claim 9, wherein inserting the transmitter identification information comprises: And inserting the transmitter identification information into the field synchronization signal and additionally inserting a start reference signal (PN Sync) indicating that the transmitter identification information has been inserted before the transmitter identification information. How to insert transmitter information. The method of claim 9, wherein inserting the transmitter identification information comprises: And inserting transmitter identification information into a reserved area of the field synchronization signal. Receiving a data frame; Detecting transmitter identification information from a field synchronization signal of the data frame; Providing preset transmitter identification information of each transmitter; And And detecting transmitter information based on the detected transmitter identification information and the provided transmitter identification information. 13. The method of claim 12, wherein a correlation operation between the detected transmitter identification information and the provided transmitter identification information is performed, and a transmission time-offset and a size of the corresponding transmitter are set using the result of the correlation operation. The method of claim 1, further comprising adjusting the transmitter. The method of claim 12, wherein the detecting of the transmitter identification information comprises: And detecting the transmitter identification information inserted into the reserved area of the field synchronization signal. The method of claim 12, wherein the detecting of the transmitter identification information comprises: And detecting the inserted transmitter identification information by using a start reference signal (PN Sync) indicating that the transmitter identification information has been inserted later in the field synchronization signal. The method of claim 12, wherein providing the transmitter identification information comprises: And transmitting and storing the preset transmitter identification information. The method of claim 12, wherein providing the transmitter identification information comprises: And generating the preset transmitter identification information in a predetermined manner and providing the preset transmitter identification information.

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