This application claims priority from Korean Patent Application No. 10-2009-17270, filed on Feb. 27, 2009, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to a common broadcast receiver and a method for receiving a broadcast signal, and more particularly, to a broadcast receiver for receiving and processing a cable broadcast signal, a terrestrial broadcast signal, and a mobile broadcast signal all together, and a method for processing the received signals.
2. Description of the Related Art
Thanks to the advance of digital technologies, digital video processing systems, such as digital TVs, are widely provided. In addition, various digital broadcasting standards for processing the digital broadcast signals are suggested.
Among the various digital broadcasting standards, in the digital broadcasting of the U.S.A., the terrestrial broadcasting conforms to ATSC A. 53 (8-VSB) broadcasting standard and the cable broadcasting confirms to ITU-T J. 83 (QAM scheme) broadcasting standard.
Digital broadcasting allows for high-quality broadcasting and features higher propagation efficiency than analog broadcasting, to thus transmit and receive more information. Disadvantageously, digital broadcasting suffers from broadcast interruption when the transport stream is compromised by an ambient magnetic field or obstacle.
Recently, the above-stated problem has gotten worse in various mobile devices such as cellular phones, PDAs, PMPs, and MP3 players, receiving digital broadcasts. In this respect, ATSC Mobile/Handheld (M/H) broadcasting standard has been introduced for digital broadcasting using mobile devices in the U.S.A.
In this regard, a common receiver is needed for receiving and detecting cable broadcasts, terrestrial broadcasts, and mobile broadcasts.
Exemplary embodiments of the present invention overcome the above disadvantages and other disadvantages not described above. Also, the present invention is not required to overcome the disadvantages described above, and an exemplary embodiment of the present invention may not overcome any of the problems described above.
The present invention provides a common broadcast receiver for receiving a cable broadcast signal, a terrestrial broadcast signal, and a mobile broadcast signal all together, and a broadcast receiving method thereof.
Consistent with an aspect of the present invention, a common broadcast receiver for receiving and processing a plurality of broadcast signals, includes a synchronizer for receiving any one of a cable broadcast signal, a terrestrial broadcast signal, and a mobile broadcast signal including a training signal generated by a Deterministic Trellis Reset (DTR) and inserted in a data region, and synchronizing the received broadcast signal; and a signal detector for detecting any one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal from the synchronized broadcast signal.
The signal detector may include a broadcasting mode determiner for determining which one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal is the synchronized broadcast signal; an equalizer for equalizing the synchronized broadcast signal according to the determined broadcasting mode; and an Forward Error Correction (FEC) part for correcting error of the equalized signal.
The equalizer and the FEC part each may include a plurality of equalizers and a plurality of FEC parts corresponding to the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal respectively.
The equalizer and the FEC part each may include a common equalizer and a common FEC part capable of processing the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal all together.
The broadcasting mode determiner may determine the synchronized broadcast signal as the cable broadcast signal when a 1-byte sync signal is repeatedly detected from the synchronized broadcast signal in a preset cycle.
The broadcasting mode determiner may determine the synchronized broadcast signal as the cable broadcast signal when a field sync signal region is not detected from the synchronized broadcast signal.
The broadcasting mode determiner may determine that the field sync signal region is detected when the synchronized broadcast signal includes any one of a Pseudo Noise (PN) sequence in a preset form, a Vestigial SideBand (VSB) mode, and a reserved region.
The broadcasting mode determiner may determine the synchronized broadcast signal as the mobile broadcast signal when a training signal is inserted to a data region of the synchronized broadcast signal.
The broadcasting mode determiner may determine whether the synchronized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, according to a feature code value in a field sync signal region of the synchronized broadcast signal.
The broadcasting mode determiner may determine the synchronized broadcast signal as the mobile broadcast signal when a PN sequence in a preset size exists in a reserved region of a field sync signal region of the synchronized broadcast signal.
The broadcasting mode determiner may determine the synchronized broadcast signal as the mobile broadcast signal when a FEC coding is performed on symbols of a preset size in a reserved region of a field sync signal region of the synchronized broadcast signal.
The broadcasting mode determiner may assume that the synchronized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, output an error-corrected signal when the error-corrected signal is a normal signal, and modify the assumption and carry out the equalization and the error correction in order when the error-corrected signal is an error signal.
The signal detector may include an equalizer for equalizing the synchronized broadcast signal; a broadcasting mode determiner for determining which one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal is the equalized broadcast signal; and an FEC part for correcting error according to the determined broadcast signal.
The broadcasting mode determiner may determine whether the equalized broadcast signal is the cable broadcast signal according to a constellation of the equalized broadcast signal.
The broadcasting mode determiner may determine the equalized broadcast signal as the cable broadcast signal when a 1-byte sync signal is repeatedly detected from the equalized broadcast signal in a preset cycle.
The broadcasting mode determiner may determine the equalized broadcast signal as the cable broadcast signal when a field sync signal region is not detected from the equalized broadcast signal.
The broadcasting mode determiner may determine that the field sync signal region is detected, when the equalized broadcast signal includes any one of a PN sequence in a preset form, a VSB mode, and a reserved region.
The broadcasting mode determiner may determine the equalized broadcast signal as the mobile broadcast signal when a training signal is inserted to a data region of the equalized broadcast signal.
The broadcasting mode determiner may determine whether the equalized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, according to a feature code value in a field sync signal region of the equalized broadcast signal.
The broadcasting mode determiner may determine the equalized broadcast signal as the mobile broadcast signal when a PN sequence of a preset size exists in a reserved region of a field sync signal region of the equalized broadcast signal.
The broadcasting mode determiner may determine the equalized broadcast signal as the mobile broadcast signal when a FEC coding is performed on symbols of a preset size in a reserved region of a field sync signal region of the equalized broadcast signal.
The broadcasting mode determiner may assume that the equalized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, output an error-corrected signal when the error-corrected signal is a normal signal, and modify the assumption and carry out the equalization and the error correction in order when the error-corrected signal is an error signal.
Consistent with another aspect of the present invention, a method for processing a received signal of a common broadcast receiver which receives and processes a plurality of broadcast signals, includes receiving any one of a cable broadcast signal, a terrestrial broadcast signal, and a mobile broadcast signal including a training signal generated by a DTR and inserted in a data region, and synchronizing the received broadcast signal; and detecting any one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal from the synchronized broadcast signal.
The detecting operation may include determining which one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal is the synchronized broadcast signal; equalizing the synchronized broadcast signal according to the determined broadcasting mode; and correcting error of the equalized signal.
The determining operation may determine the synchronized broadcast signal as the cable broadcast signal when a 1-byte sync signal is repeatedly detected from the synchronized broadcast signal in a preset cycle.
The determining operation may determine the synchronized broadcast signal as the cable broadcast signal when a field sync signal region is not detected from the synchronized broadcast signal.
The determining operation may determine that the field sync signal region is detected when the synchronized broadcast signal includes any one of a PN sequence in a preset form, a VSB mode, and a reserved region.
The determining operation may determine the synchronized broadcast signal as the mobile broadcast signal when a training signal is inserted to a data region of the synchronized broadcast signal.
The determining operation may determine whether the synchronized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, according to a feature code value in a field sync signal region of the synchronized broadcast signal.
The determining operation may determine the synchronized broadcast signal as the mobile broadcast signal when a PN sequence in a preset size exists in a reserved region of a field sync signal region of the synchronized broadcast signal.
The determining operation may determine the synchronized broadcast signal as the mobile broadcast signal when a FEC coding is performed on symbols of a preset size in a reserved region of a field sync signal region of the synchronized broadcast signal.
The determining operation may assume that the synchronized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, output an error-corrected signal when the error-corrected signal is a normal signal, and modify the assumption and carry out the equalization and the error correction in order when the error-corrected signal is an error signal.
The detecting operation may include equalizing the synchronized broadcast signal; determining which one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal is the equalized broadcast signal; and correcting error according to the determined broadcast signal.
The determining operation may determine whether or not the equalized broadcast signal is the cable broadcast signal according to a constellation of the equalized broadcast signal.
The determining operation may determine the equalized broadcast signal as the cable broadcast signal when a 1-byte sync signal is repeatedly detected from the equalized broadcast signal in a preset cycle.
The determining operation may determine the equalized broadcast signal as the cable broadcast signal when a field sync signal region is not detected from the equalized broadcast signal.
The determining operation may determine that the field sync signal region is detected, when the equalized broadcast signal includes any one of a PN sequence in a preset form, a VSB mode, and a reserved region.
The determining operation may determine the equalized broadcast signal as the mobile broadcast signal when a training signal is inserted to a data region of the equalized broadcast signal.
The determining operation may determine whether the equalized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, according to a feature code value in a field sync signal region of the equalized broadcast signal.
The determining operation may determine the equalized broadcast signal as the mobile broadcast signal when a PN sequence of a preset size exists in a reserved region of a field sync signal region of the equalized broadcast signal.
The determining operation may determine the equalized broadcast signal as the mobile broadcast signal when a FEC coding is performed on symbols of a preset size in a reserved region of a field sync signal region of the equalized broadcast signal.
The determining operation may assume that the equalized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal, output an error-corrected signal when the error-corrected signal is a normal signal, and modify the assumption and carry out the equalization and the error correction in order when the error-corrected signal is an error signal.
Additional and/or other aspects of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
The above and/or other aspects of the present invention will be more apparent by describing certain exemplary embodiments of the present invention with reference to the accompanying drawings, in which:
Certain exemplary embodiments of the present invention will now be described in greater detail with reference to the accompanying drawings.
In the following description, the same drawing reference numerals are used for the same elements even in different drawings. The matters defined in the description, such as detailed construction and elements, are provided to assist in a comprehensive understanding of the invention. Thus, it is apparent that the exemplary embodiments of the present invention can be carried out without those specifically defined matters. Also, well-known functions or constructions are not described in detail since they would obscure the invention with unnecessary detail.
The synchronizer 110 receives any one of a cable broadcast signal, a terrestrial broadcast signal, and a mobile broadcast signal including a training signal generated by a Deterministic Trellis Reset (DTR) and inserted in a data region, and synchronizes the received broadcast signal.
The signal detector 120 detects any one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal from the synchronized broadcast signal.
Although it is not illustrated in
Although it is not illustrated in
The common broadcast receiver 100 can be implemented in the form of a single chip, equipped to a hand phone, a navigator, an MP3 player, a PMP, and so on, and embedded to the broadcast receiver of a desktop computer, TV, or a set-top box.
Prior to the descriptions on the common broadcast receiver 100 according to an exemplary embodiment of the present invention, the cable broadcast signal, the terrestrial broadcast signal, the mobile broadcast signal transmitted from the transmitting side to the common broadcast receiver 100 are explained in detail.
A structure of a transmitter for transmitting the cable broadcast signal from the transmitting side and a structure of a transmitter for transmitting the terrestrial broadcast signal from the transmitting side, which are well known to one skilled in the art, shall be omitted here. A structure of a transmitter for transmitting the mobile broadcast signal from the transmitting side and the mobile broadcast signal including the inserted training signal generated by the DTR are now elucidated by referring to the drawings.
In the 104 symbols of the reserved region of
The MUX 910 generates a transport stream including a normal data stream and an additional data stream. The normal data stream represents a data stream transmitted for the broadcast in a conventional digital broadcasting system. The additional data stream represents a stream robust to error, which can be processed at a mobile device, and processed by applying a coding rate using a coding scheme different from the normal data stream. Ultimately, the terrestrial broadcast signal does not include the additional data stream, whereas the mobile broadcast signal can include the additional data stream in addition to the normal data stream.
The MUX 910 can generate the transport stream by properly formatting and inserting the additional data stream to the normal data stream.
In more detail, the MUX 910 can sequentially insert one or more additional data streams over the normal data stream units in a preset pattern in an alternating manner. Herein, the stream unit indicates the unit defined to distinguish the normal data and can be a segment unit or a packet unit.
The exciter 920 processes the transport stream generated at the MUX 910 and transmits the processed transport stream in the channel. The exciter 920 performs trellis encoding on the transport stream, resets memories used for the trellis encoding at a certain time point, and inserts the training signal, which is known between the transmitter and the receiver, to the transport stream. That is, the exciter 920 can carry out the DTR which resets the memories used for the trellis encoding at a certain time point. It is noted that the DTR is performed only on the mobile broadcast signal.
Herein, the training signal is inserted to the data region of the transport stream and can be generated in the size greater than the field sync signal. As shown in
The MUX 912 generates the transport stream by inserting the one or more additional data streams T output from the additional data processor 911 to the normal data stream N.
The additional data processor 911 can include a single preprocessor or a plurality of preprocessors (not shown) according to the number of the additional data. The preprocessor (not shown) can include an RS-encoder (not shown), an interleaver (not shown), and a packet formatter (not shown). Through the RS encoding, the interleaving, and the packet formatting, the additional data streams can be made to be robust to errors.
The additional data stream input to the preprocessor (not shown) is encoded at the RS-encoder (not shown) and interleaved by the interleaver (not shown). The packet formatter (not shown) packet-formats the additional data stream output from the interleaver.
A randomizer 921 randomizes the generated transport stream.
A training signal inserter 922 inserts the training signal, which is known to the receiving side, into the transport stream. The inserted training signal can be used by the receiving side to determine whether or not the received transport stream contains the additional data stream. Also, the inserted training signal can be used for the demodulation or the equalization of the receiving side to thus enhance the reception performance. Herein, the training signal is in the size greater than the field sync signal and can be inserted over two segments. Accordingly, the training signal can be a long training symbol.
An RS encoder 923 encodes the transport stream including the inserted training signal. An interleaver 924 interleaves the encoded transport stream and provides the interleaved transport stream to a trellis encoder 925.
The trellis encoder 925 trellis-encodes the interleaved transport stream and outputs the trellis-encoded transport stream to a sync MUX 927.
The trellis encoder 925 can perform the trellis resetting at a proper time according to the insertion of the training signal. In further detail, the trellis encoder 925 can employ a plurality of internal memories (e.g., 3 shift registers) in the trellis encoding. When the trellis encoding is conducted on the training signal, known data values can be modified by values pre-stored to the internal memories. To avoid this, prior to the processing of the training signal, it is advantageous to perform the trellis resetting which resets the interval memories to their initial values. When the trellis resetting is carried out, parity correction may be conducted to avoid incorrectness of the parity in accordance with the trellis resetting. In this case, an RS re-encoder (not shown) can be further provided, which shall be described in more detail by referring to
A field sync generator 926 generates the field sync signal to be inserted to the transport stream.
According to the field sync signal generated at the field sync generator 926, the mobile broadcast signal can be generated in the form different from the cable broadcast signal and the terrestrial broadcast signal.
The sync MUX 927 inserts the field sync signal generated at the field sync generator 926 and the segment sync signal into the trellis-encoded transport stream.
A modulator 928 modulates the transport stream processed at the sync MUX 927 and transmits the modulated transport stream over the channel. More specifically, the modulator 928 can convert the transport stream to an RF channel signal through VSB modulation, RF modulation, and so forth.
In various exemplary embodiments, other various components than the components of
In various embodiments, some of the components of
Referring to
The trellis encoder 925 of
The MUX 330 can function in one of an operation mode for trellis-encoding each packet of the input transport stream (hereinafter, referred to as a normal mode), and an operation mode for trellis-encoding the packets added by the adder 320 (hereafter, referred to as a parity correction mode). The operation mode of the MUX 330 is determined by a control signal received from the RS re-encoder 310.
In the normal mode, the MUX 330 forwards the input transport stream to the trellis encoder block 350. By contrast, in the parity correction mode, the MUX 330 forwards the stream output from the adder 320 to the trellis encoder block 350.
The trellis encoder block 350 trellis-encodes the packets received from the MUX 330. The trellis encoder block 350 can trellis-encode the packets according to the external control signal. Advantageously, the above-stated training signal is initialized right before the trellis encoding. To prevent the training signal from being distorted by the pre-stored value of its memory, the trellis encoder block 350 initializes the training signal before the trellis encoding by locating the insertion position of the training signal.
The RS re-encoder 310 re-generates the parity corresponding to the changed packet using the initial value calculated in the initialization of the trellis encoder block 350.
The adder 320 adds the parity re-generated by the RS re-encoder 310 and the packet fed from the outside and provides the added packets to the MUX 330. Herein, the addition is conducted as follows.
A. omitted . . . 101001010111001010101011AAAAA . . . omitted
B. omitted . . . 000000000000010000000000BBBBB . . . omitted
C. omitted . . . 101001010111011010101011CCCCC . . . omitted
A) shows the packet input from the outside, B) shows the RS-re-encoded packet, and C) shows the result of the Exclusive OR of A) and B) using the adder 320. When the underlined part in the packet A) is input to the trellis encoder block 350, the initialization is performed. In this case, the value corresponding to the value pre-stored to the trellis encoder block 350 is provided to the RS re-encoder 310 and the RS re-encoder 310 adds the parity to the input value and outputs the packet B). The underlined part in the packet B) indicates the modified value corresponding to the underlined part of the packet A). The parity corresponding to the underlined part of the packet B) is BBBB, which is regenerated.
The adder 320 outputs the packet C) by applying the exclusive OR to the packet A) and the packet B). In the packet C), the underlined part in the initially input packet A) is modified to “01” and the parity is changed from AAAAA to CCCCC.
The MUX 330 enters the normal operation mode when the initialization and the parity correction are completed, and provides the dual transport stream to the trellis encoder block 350.
The MAP 340 symbol-maps the trellis-encoded packets to 8 levels. The MAP 340 can carry out the mapping as shown in Table 1.
In Table 1, Z0, Z1 and Z2 denotes the trellis encoding value output from the trellis encoder block 350, and R denotes the corresponding mapping output value. For example, when the trellis encoding value of 0, 0, 0 is output, the MAP 340 outputs −7.
The splitter 352 outputs the stream output from the MUX 330 to the trellis encoders 351-1 through 351-12 in sequence. In so doing, the splitter 352 can output the stream on a byte basis.
The trellis encoders 351-1 through 351-12 each trellis-encode the input stream. The trellis encoder 1 through the trellis encoder 12 are selected in succession to output the trellis encoding value. Meanwhile, in the initialization period, the trellis encoders 351-1 through 351-12 provide the value pre-stored to their interval memories (not shown) to the RS re-encoder 310 as the initial value. The RS re-encoder 310 corrects the parity by adding the parity to the fed initial value and outputting to the adder 320.
The encoding output part 353 sequentially detects the encoding values output from the trellis encoders 351-1 through 351-12 and outputs the detected encoding values to the MAP 340.
The trellis encoders 351-1 through 351-12 each include a plurality of memories for the trellis encoding. Just prior to the trellis encoding, the region where a supplementary reference signal is inserted is initialized. Each individual memory is reset according to the initialization. In so doing, the value pre-stored to the memory is provided to the RS re-encoder 310 as the initial value.
In further detail, each trellis encoder can include three memories; that is, a first memory, a second memory, and a third memory. As the initialization proceeds, the first memory outputs the previously stored value (hereafter, referred to as a first initial value) as the initial value. The third memory shifts the previously stored value, to the second memory concurrently with the initialization. According to the shift operation, the value pre-stored to the second memory (hereafter, referred to as a second initial value) is output as the initial value. The RS re-encoder 310 combines the first and second initial values and utilizes the combined value as the initial value.
Since the second and third memories, which are arranged side by side, execute the shift operation, two control signal symbols are required to initialize all of the second memory and the third memory. There are 8 cases (000, 111, 001, 010, 100, 110, 101 and 011) of the initial value condition produced using all of the three memories. X0 and X1 values denoting the first and second initial values are fed to the RS re-encoder 310, to thus modify the parity.
The broadcasting mode determiner 1410 determines whether the synchronized broadcast signal is the cable broadcast signal, the terrestrial broadcast signal, or the mobile broadcast signal. The equalizer 1420 equalizes the synchronized broadcast signal according to the determined broadcasting mode. The FEC part 1430 corrects errors in the equalized signal.
Herein, when the broadcast signal determined at the broadcasting mode determiner 1410 is the cable broadcast signal, the equalizer 1420 equalizes the broadcast signal according to the cable broadcasting mode and the FEC part 1430 corrects errors according to the cable broadcast signal. In more detail, according to the broadcasting mode corresponding to the broadcast signal, the equalizer 1420 and the FEC part 1430 can perform the equalization and the error correction respectively. In so doing, the equalizer 1420 and the FEC part 1430 can include a plurality of equalizers (not shown) and a plurality of FEC parts (not shown) corresponding to the respective broadcast signals.
Typically, the equalizer 1420 and the FEC part 1430 have different structures depending on the broadcast signal as mentioned above. Since the substantial function of the equalizer 1420 and the FEC part 1430 is practically similar, a common equalizer (not shown) and a common FEC part (not shown) may be provided.
The broadcasting mode determiner 1410 can determine one of the received broadcast signals in various manners. For example, the broadcasting mode determiner 1410 can determine whether the received broadcast signal is the cable broadcast signal and then determine whether the received broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal.
When the 1-byte sync signal is detected from the synchronized broadcast signal repeatedly in a preset cycle, the broadcasting mode determiner 1410 can determine the synchronized broadcast signal as the cable broadcast signal. Referring back to
When not detecting the field sync signal region from the synchronized broadcast signal, the broadcasting mode determiner 1410 can determine the synchronized broadcast signal as the cable broadcast signal. Herein, upon detecting any one of the PN sequence in the predefined form, the VSB mode, and the reserved region in the synchronized broadcast signal, the broadcasting mode determiner 1410 determines the detection of the field sync signal region. More specifically, since the cable broadcast signal does not include the field sync signal region as shown in
When the training signal is inserted in the data region of the synchronized broadcast signal, the broadcasting mode determiner 1410 can determine the synchronized broadcast signal as the mobile broadcast signal. Referring back to
As the receiving side can locate the field sync signal region as stated above, the location of the training symbol can be acquired based on the location of the field sync signal. Referring back to
Alternatively, based on the feature code value in the field sync signal region of the synchronized broadcast signal, the broadcasting mode determiner 1410 can determine which one of the terrestrial broadcast signal and the mobile broadcast signal is the synchronized broadcast signal. Referring back to
Alternatively, when the PN sequence of the preset size exists in the reserved region of the field sync signal region of the synchronized broadcast signal, the broadcasting mode determiner 1410 can determine the synchronized broadcast signal as the mobile broadcast signal. Referring back to
Alternatively, when the FEC coding is performed on the symbols of the preset size in the reserved region of the field sync signal region of the synchronized broadcast signal, the broadcasting mode determiner 1410 can determine that the synchronized broadcast signal is the mobile broadcast signal. Referring back to
Alternatively, the broadcasting mode determiner 1410 assumes that the synchronized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal. Next, when the error-corrected signal output from the FEC part 1430 is the normal signal, the error-corrected signal is output. When the error-corrected signal is an error signal, the assumption is modified, the equalizer 1420 performs the equalization, and the FEC part 1430 sequentially performs the error correction. Thus, the broadcasting mode determiner 1410 can determine whether the synchronized broadcast signal is either the terrestrial broadcast signal or the mobile broadcast signal.
In
When the signal input to the broadcasting mode determiner 1410 is the terrestrial broadcast signal, the first determiner 1412 can identify that the input signal is not the cable broadcast signal and the second determiner 1414 can determine the signal input to the broadcasting mode determiner 1410 as the terrestrial broadcast signal using the above-stated methods. Next, the signal output from the second determiner 1414 can pass through the equalization at the equalizer 1420 and the error correction at the FEC part 1430. When the signal input the broadcasting mode determiner 1410 is the terrestrial broadcast signal, the operations are the same as for the terrestrial broadcast signal.
In
By contrast, when the input signal to the first determiner 1412 is the terrestrial broadcast signal, it is advantageous that the second determiner 1414 follows the first determiner 1412 as shown in
The broadcasting mode determiner 1620 can determine whether the equalized broadcast signal is the cable broadcast signal or not, according to the constellation of the equalized broadcast signal.
In
Similar to
In
When the input signal to the equalizer 1610 is the terrestrial broadcast signal and the signal passing through the first determiner 1622 is determined as the terrestrial broadcast signal at the second determiner 1624, the error correction can be executed at the FEC part 1630. By contrast, when the input signal to the equalizer 1610 is the terrestrial broadcast signal and the signal passing through the first determiner 1622 is determined as the mobile broadcast signal at the second determiner 1624, a controller (not shown) feeds the input signal of the second determiner 1624 back to the equalizer 1610. Next, the equalizer 1610 fulfils the equalization by assuming the mobile broadcast signal and the controller (not shown) applies the equalized signal directly to the FEC part 1630 to pass through the error correction. It is noted that the controller (not shown) can set that the equalized signal passes through the broadcasting mode determiner 1620 without any operation. The descriptions on the case where the input signal of the equalizer 1610 is the mobile broadcast signal shall be omitted for the brevity.
Unlike
The signal detector of
In contrast to
Next, the broadcasting mode determiner 1410 of the signal detector 120 or 1400 determines which one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal is the synchronized broadcast signal (S2020).
The equalizer 1420 of the signal detector 120 or 1400 equalizes the synchronized broadcast signal according to the determined broadcasting mode (S2030), and the FEC part 1430 of the signal detector 120 or 1400 corrects error of the equalized signal (S2040).
The equalizer 1610 of the signal detector 120 or 1600 equalizes the synchronized broadcast signal (S2120).
The broadcasting mode determiner 1620 of the signal detector 120 or 1600 determines which one of the cable broadcast signal, the terrestrial broadcast signal, and the mobile broadcast signal is the equalized broadcast signal (S2130). The FEC part 1630 of the signal detector 120 or 1600 corrects errors according to the determined broadcast signal (S2140).
The embodiments of the present invention can include a computer recording medium containing a program for executing the various broadcast signal processing methods of the common broadcast receiver as set forth above.
Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
Number | Date | Country | Kind |
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10-2009-0017270 | Feb 2009 | KR | national |