JP2011114593A - Digital broadcast receiving apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique of shortening of time required for automatic start, reduction of power consumption, and start in a digital broadcast receiving apparatus when an emergency earthquake warning is broadcast. <P>SOLUTION: The digital broadcast receiving apparatus receives a transmission signal having a digital broadcast signal, a start flag indicating that the emergency earthquake warning is issued, and an emergency earthquake information signal including signal identification information indicating the content of the emergency earthquake warning, and includes: a flag detection part which detects the start flag from the emergency earthquake information signal of the transmission signal received by the receiving part; and a control part which turns the receiving apparatus into a first power consumption state when the start flag detected by the flag detection part indicates that the emergency earthquake warning is issued, and turns the receiving apparatus into a second power consumption state higher than the first power consumption state when there is the content indicating that an area where strong shake is predicted is included in an area under reception. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a digital broadcast receiving apparatus capable of receiving an earthquake early warning transmitted by digital broadcasting, and more particularly to a digital broadcast receiving apparatus that can be activated at low speed with low power consumption.

  The terrestrial digital broadcasting system in Japan is operated as an ISDB-T (Integrated Service Digital Broadcasting-Terrestrial) system. In this ISDB-T system, a plurality of MPEG-2 transport streams (MPEG-2 Transport Streams, hereinafter referred to as TS) are re-multiplexed into one TS, subjected to transmission path coding processing, and then subjected to IFFT (Inverse It is converted into an OFDM (Orthogonal Frequency Division Multiplexing) transmission signal composed of a plurality of subcarriers by Fast Fourier Transform and transmitted as a broadcast wave.

  Here, the OFDM transmission signal in the ISDB-T system has a configuration in which 13 OFDM segments obtained by dividing a transmission bandwidth of 6 MHz by 14 are connected, and hierarchical transmission of up to three layers is possible in units of OFDM segments. It has become. In addition, among the 13 segments of the OFDM transmission signal, the central segment (segment number # 0) can be set as a partial reception layer assuming reception by a mobile receiver such as a mobile phone. A receiver that can receive all 13 segments of the OFDM transmission signal is called a 13-segment receiver, and a receiver that can receive one central segment of the OFDM transmission signal is called a one-segment receiver.

  The OFDM transmission signal in the ISDB-T system is a TMCC (transmission of control information for smoothly performing demodulation operation of the receiver, such as system identification, transmission parameter switching index, emergency warning broadcast activation flag, transmission parameter of each layer, and the like. The frame configuration includes a transmission and multiplexing configuration control (AC) signal and an AC (Auxiliary Channel) signal that is an extension signal for transmitting additional information related to transmission control of the modulated wave. In this frame configuration, the carrier positions and the number of carriers of the TMCC signal and AC signal added as OFDM subcarriers vary depending on the transmission parameters, and are defined in Non-Patent Document 1, for example.

Here, an emergency warning system (EWS: Emergency Warning System) activated by an emergency warning broadcast activation flag transmitted by TMCC refers to emergency information to viewers when a tsunami warning due to the occurrence of an earthquake is issued. It is used to inform more quickly. When the emergency warning broadcast is operated in the ISDB-T system, the broadcasting station sets the emergency warning broadcast activation flag included in the TMCC signal to “1” and broadcasts the content with the content that can be recognized as the emergency warning broadcast. The receiver monitors the emergency warning broadcast activation flag, and if the emergency warning broadcast activation flag is “1”, the viewer is forced to change the service or shift from the standby state to the normal energized state. It is possible to provide emergency alert broadcasting quickly. (See Patent Document 1)
Further, as a system for transmitting more advanced emergency information, there is an earthquake early warning (EEW) announced by the Japan Meteorological Agency. The Earthquake Early Warning is a method for immediately estimating the magnitude of an epicenter or earthquake by analyzing initial microtremors (so-called P waves) and main motions (so-called S waves) captured by a seismometer near the epicenter immediately after the occurrence of an earthquake. This is information that estimates the seismic intensity of major motions in each location based on the information and informs it as quickly as possible. In addition, the Earthquake Early Warning is intended to ensure the safety of the viewer without panicking according to the surrounding situation by notifying the viewer before a strong shake arrives. As a method for transmitting the earthquake early warning by the ISDB-T method, a system for transmitting the earthquake early warning using an AC signal included in the segment number # 0 has been studied. As an example of using the earthquake early warning system in the ISDB-T system, an alarm clock with an automatic warning function that issues an alarm by receiving an earthquake early warning by a one-segment receiver is disclosed. (See Non-Patent Documents 1 and 2)

JP 2005-333512 A

"Transmission method for digital terrestrial television broadcasting standard ARIB STD-B31 1.7 version", Radio Industry Association, established on May 31, 2001, revised to 1.7 version on September 26, 2007 "Automatic activation of receiving terminal by emergency broadcasting" 2008 public exhibition of Giken Exhibit materials NHK Broadcasting Technology Laboratories May 20, 2008

  The non-patent document 2 discloses the necessity of automatically starting a digital broadcast receiver when an emergency earthquake bulletin is broadcast.

  Moreover, the above-mentioned Patent Document 1 discloses a reduction in power consumption in a so-called standby state in which emergency alert broadcasting is monitored.

  However, none of the documents discloses high-speed activation and low power consumption in receiving operation when receiving an earthquake early warning.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a digital broadcast receiver capable of receiving an earthquake early warning transmitted by digital broadcasting when the earthquake early warning is broadcast. It is another object of the present invention to provide a detailed operation of a digital broadcast receiving apparatus which can be started up at high speed with low consumption.

  In order to achieve the above object, the present invention (1) shows a digital broadcast signal including a video signal or an audio signal, an activation flag indicating that an emergency earthquake warning has been issued, and the contents of the emergency earthquake warning. A digital broadcast receiving apparatus that receives a transmission signal having an emergency earthquake information signal including signal identification information, the receiving unit receiving the transmission signal, and the emergency earthquake information among the transmission signals received by the receiving unit From the signal, a flag detection unit for detecting an activation flag, a determination unit for determining the content of signal identification information from an emergency earthquake information signal among transmission signals received by the reception unit, and a determination unit When the output unit that outputs the content of the signal identification information and the activation flag detected by the flag detection unit indicate that an emergency earthquake warning has been issued, the device is set to the first power consumption state, The second power higher than the first power consumption state when there is a content indicating that a region where strong shaking is expected is included in the area being received among the content determined by the separate unit And a control unit to be in a consumption state.

  Also, in the present invention (2), in the present invention (1), the receiving unit includes a video / audio output unit that outputs a video signal or an audio signal of a digital broadcast signal among the received transmission signals, The contents of the signal identification information output from the output unit are output from the video / audio output unit.

  In the present invention (1), the first power consumption state is a state in which the determination unit operates and the output unit prepares for operation and does not output, and the second power consumption state. Is a state in which the determination unit and the output unit operate together.

  In the present invention (2), when the video / audio output unit does not output a video signal or an audio signal, the first power consumption state means that the determination unit operates and the output unit Is ready for operation, the receiver is not ready for operation and does not output, and the second power consumption state is the state in which the determination unit, the output unit, and the receiver are operating. is there.

  Also, in the present invention (2), when the video / audio output unit outputs a video signal or an audio signal, the first power consumption state means that the determination unit operates and the output unit Is a state in which the receiving unit is outputting a video signal or an audio signal, and the second power consumption state is that the determination unit and the output unit operate, and the receiving unit This is a state in which a video signal or an audio signal is switched to the content of signal identification and output.

  In the present invention (1) or (2), the contents discriminated by the discriminating section are contents indicating that an area where strong shaking is expected is not included in the area being received, activation of earthquake early warning The content indicating that it is a test signal for the test is included.

  In the present invention (1) or (2), the emergency earthquake information signal includes time information, area information, and epicenter information relating to an earthquake, and the determination unit is configured to transmit a transmission signal received by the reception unit. Time information, regional information, and epicenter information related to the earthquake are discriminated from the emergency earthquake information signal, and the output unit determines the time information, regional information, and epicenter information related to the earthquake determined by the discriminating unit. Output.

  Also, in the present invention (1) or (2), the emergency earthquake information signal includes issue time information when an earthquake early warning is issued, and the output unit sets a time for setting current time information An emergency earthquake, and a determination unit that determines whether a difference between the current time information and the notification time information is within a predetermined range, and a result determined by the determination unit is within a predetermined range A warning unit is provided to notify that a breaking news has been issued, and the output unit notifies that an emergency earthquake warning has been issued in the first power consumption state.

  According to the present invention, there is provided a digital broadcast receiver capable of receiving an earthquake early warning transmitted by digital broadcast, wherein the digital broadcast receiver is activated at high speed with low consumption when the earthquake early warning is broadcast. Can be provided.

It is a block diagram which shows the structure of the digital broadcast receiver which can receive the earthquake early warning based on the 1st Embodiment of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is explanatory drawing which shows the structure of the emergency earthquake information received with the emergency earthquake information receiving part 120 which is a main block of this invention. It is a block diagram which shows one Example of the output part 117 which is a main block of the 1st Embodiment of this invention. It is a block diagram which shows the structure of the digital broadcast receiver which can receive the earthquake early warning based on the 2nd Embodiment of this invention. It is a block diagram which shows one Example of the output part 1101 which is the main blocks of the 2nd Embodiment of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts. Further, the present invention is not limited to the illustrated example.

  1 is a digital broadcast that receives emergency earthquake information transmitted using an AC signal included in segment number # 0 in the ISDB-T system, which is a Japanese terrestrial digital television broadcast system in Embodiment 1 according to the present invention. It is a block diagram which shows the structure of a receiver.

  Reference numeral 101 denotes an antenna, 102 denotes a channel selection unit, 103 denotes an orthogonal demodulation unit, 104 denotes a fast Fourier transform (hereinafter referred to as FFT) unit, and 105 denotes demodulation and decoding that performs demodulation and decoding operations in the ISDB-T system from the FFT unit 104 to the TS output. , 106 is a descrambling unit, 107 is a demux unit, 108 is a video signal and audio signal decoding unit, 109 is a video display unit for displaying the decoded video signal, and 110 is for outputting the decoded audio signal. An audio output unit, which is a mainstream block for reproducing a video signal and an audio signal. Reference numeral 111 denotes a synchronous reproduction unit, 112 denotes a frame extraction unit, and 113 denotes a TMCC decoding unit. The channel selection unit 102 to the TMCC decoding unit 113 constitute a broadcast reception unit 119.

  On the other hand, 114 is a flag detection unit, 115 is a data extraction unit, 116 is a discrimination unit, and 117 is an emergency earthquake early warning output unit. These components constitute an emergency earthquake information reception unit 120.

  Reference numeral 118 denotes a control unit that performs operation control and power control of the broadcast receiving unit 119 and the emergency earthquake information receiving unit 120.

  The control part 118, the broadcast receiving part 119, and the emergency earthquake information receiving part 120 constitute a digital broadcast receiving apparatus 121.

  Hereinafter, the operation will be described in detail. A channel frequency band to be received by the channel selection unit 102 is extracted from the ISDB-T broadcast received by the antenna 101, converted into a baseband signal by the orthogonal demodulation unit 103, and converted to frequency axis processing by the FFT unit 104. In response to this, the demodulation and decoding unit 105 performs demodulation processing on each carrier on the frequency axis, and performs error correction such as deinterleaving on the frequency axis and time axis, Viterbi decoding, and RS (Reed-Solomon) decoding. Then, the ISDB-T signal is demodulated, and a transport stream (hereinafter abbreviated as TS) signal is output to the descrambling unit 106. The descramble unit 106 scrambles the TS signal that has been scrambled for copyright protection, and outputs the descrambled signal to the demax unit 107. The demux unit 107 extracts a desired compressed video signal or digital signal of the compressed audio signal and outputs it to the decoding unit 108. The decoding unit 108 decodes the compressed video signal and the compressed audio signal, and outputs the decoded video signal to the video display unit 109 and the decoded audio signal to the audio output unit 110.

  On the other hand, synchronous reproduction section 111 receives a baseband signal from orthogonal demodulation section 103, reproduces a symbol synchronization signal, and detects the frequency position of the TMCC signal from the output signal of FFT section 104. The frame extraction unit 112 demodulates the TMCC signal at the detected frequency position and reproduces the frame synchronization signal. The frame synchronization signal is output to the synchronization reproduction unit 111, and phase adjustment with the symbol synchronization signal is performed. The TMCC decoding unit 113 performs error correction of the differential cyclic code on the demodulated TMCC signal to obtain TMCC information such as a hierarchical structure and transmission parameters. The TMCC information is output to the demodulation / decoding unit 105 and used as processing information for the demodulation / decoding process.

  Next, operations of the control unit 118 and the emergency earthquake information receiving unit 120, which are main parts of the present invention, will be described. The control unit 118 manages operation states of the flag detection unit 114, the data extraction unit 115, the determination unit 116, and the output unit 117 using the control signals 122, 124, 125, and 126, respectively. The operating state indicates a state of normal operation (normal), a state of not operating but a state in which it can immediately shift to a normal state (standby), and a state of not operating (stop). In order to reduce power consumption, the control unit 118 does not supply power in the stop state and limits the amount of power supply in the standby state so as to supply power to all locations during normal operation. Or control to limit the power supply location. In addition, the control unit 118 is in a standby state so that the operation unit is stored in a fixed position in the stop state so that the operation unit is normally operated in the normal state for avoiding a failure. Then, control is performed so that the fixed state is released and the machine is in a standby state at the operating position.

  The configuration of emergency earthquake information received by the emergency earthquake information receiving unit 120 will be described with reference to FIGS.

  For the transmission of emergency earthquake information, segment No. 0 AC carrier is used. The AC carrier is a transmission path for transmitting additional information for non-broadcasting, but allows emergency earthquake information to be transmitted in addition to the additional information.

  FIG. 2 shows bit assignment of 204 bits B0 to B203 of the AC signal. One bit of B0 is used as a reference for differential demodulation. The 3 bits from B1 to B3 are used as configuration identification to distinguish whether it is additional information or emergency earthquake information. Additional information or emergency earthquake information is transmitted by 200 bits B4 to B203. When sending emergency earthquake information, the same emergency earthquake information is sent on all AC carriers in segment No. 0.

  FIG. 3 shows a reference for differential demodulation. The modulation method of the AC carrier is DBPSK, and the amplitude and phase reference for differential demodulation are given by Wi in FIG. This is the same as the current ISDB-T broadcast standard.

  FIG. 4 shows bit allocation when emergency earthquake information is transmitted as an AC signal of segment No. 0.

  When the configuration identification is set to 000,010,011,100,101,111, the AC is used for broadcasters as usual, and additional information is transmitted.

  When the configuration identification is 001, 110, emergency earthquake information is transmitted.

  ‘001’ and ‘110’ representing the transmission of emergency earthquake information have the same code as the first 3 bits (B1 to B3) of the TMCC synchronization signal, and are alternately transmitted for each frame at the same timing as the TMCC signal.

  The 13 bits of B4 to B16 are used as synchronization signals. In the case of emergency earthquake information, the code obtained by concatenating the configuration identification and the synchronization signal is the same code as the TMCC synchronization signal, and is composed of a 16-bit word. There are two kinds of synchronization signals: w0 = 0011010111101110 and w1 = 1100101000010001 obtained by bit-inverting it. The same bits as the TMCC synchronization signals (B1 to B16) are allocated, and the same code as TMCC is transmitted for each frame.

  The two bits B17 to B18 are used as the earthquake early warning activation flag.

  FIG. 5 shows the meaning of the earthquake early warning activation flag.

  When the earthquake early warning is issued, 2 bits are assigned as the emergency earthquake early activation flag to indicate that the receiver is automatically activated and the emergency earthquake early warning is transmitted by an AC signal.

  In the AC signal, when there is no information to be transmitted, all bits are modulated with “1”, so that the state with the emergency earthquake warning activation control is set to “00”. In addition, in order to improve the reliability of the activation flag, 2 bits are used for the emergency earthquake warning activation flag, and an inverted signal that maximizes the intersymbol distance is used. Also, “10” and “01” are not used to ensure the reliability of the activation flag.

  The two bits B19 to B20 are used as the earthquake early warning update flag.

  FIG. 6 shows the meaning of the earthquake early warning update flag.

  If the contents of the emergency earthquake warning details (B21 to B121) are updated while the emergency earthquake warning activation control is in progress, the value of the earthquake early warning update flag is incremented by 1 as shown in FIG. Notify the aircraft that the earthquake early warning details have been updated. When there is no emergency earthquake warning activation control, a value of “11” is assumed, and the first value after switching to the emergency earthquake warning activation control is assumed to be “00”.

  The 101 bits from B21 to B121 are the details of the earthquake early warning.

  FIG. 7 shows bit allocation for details of earthquake early warning.

  The 3 bits from B21 to B23 are used for signal identification, and emergency earthquake warnings and their test signals are distinguished.

  FIG. 8 shows the meaning of emergency earthquake warning details by signal identification.

  The details of the earthquake early warning are shown in FIG. 8 by signal identification, and an EEW start signal and an EEW test signal are defined.

  The 88 bits of B24 to B111 are page type, current time, and earthquake detailed information, and the 10 bits of B112 to B121 are CRC-10.

  FIG. 9 shows the details.

  The frame structure for transmitting the EEW activation signal and the EEW test signal is as shown in B24 to B111 in FIG.

  The 10 bits B112 to B121 are CRC-10 for checking the reliability of information.

  Since emergency earthquake information is important information and requires high reliability, it is protected by an error correction code using a differential cyclic code as in TMCC. The configuration identifications B1 to B3 and the synchronization signals B4 to B16 are not subject to error correction. The information of B17 to B121 is subjected to error correction coding with the shortened code (187,105) of the difference set cyclic code (273,191). The parity bits generated by using the shortened code (187,105) of the difference set cyclic code (273,191) are set in the 82 bits of B122 to B203 similarly to the error correction code of TMCC.

  The method for using the emergency earthquake information described with reference to FIGS. 2 to 9 will be briefly described with reference to FIG.

  When emergency earthquake information is transmitted by the AC carrier of segment No. 0, the configuration identification is set to the value shown in FIG. When an earthquake occurs and an emergency earthquake warning is issued, the emergency earthquake warning activation flag is set to “with activation signal”, and at the same time, an emergency earthquake warning update flag, emergency earthquake warning details, and a parity bit are set. The emergency earthquake warning activation flag is set to “no activation signal” at the end of the earthquake early warning.

  The operation of receiving the emergency earthquake information described with reference to FIGS. 2 to 9 will be described with reference to FIG.

  The frame extraction unit 112 in FIG. 1 extracts and demodulates the AC carrier in the segment No. 0, confirms the transmission of emergency earthquake information by the configuration identification shown in FIG. 4, and further establishes synchronization. At this time, the same emergency earthquake information is sent to all AC carriers in segment No. 0. Therefore, by adding all the AC carriers in segment No. 0 in an analog manner, emergency earthquake information can be saved even if noise is reduced. Demodulation becomes possible. For example, if there are N AC carriers, the amplitude of emergency earthquake information will be N times, whereas noise will not be N times because there is no correlation in each AC carrier. Is only N times the square of N).

  Further, in the frame synchronization signal reproduction in the frame extraction unit 112, when the configuration identification portion shown in FIG. 4 is checked and it is confirmed that the emergency earthquake information is sent to the AC, as explained in FIG. Since the code connecting the configuration identification and the synchronization signal is the same as the TMCC synchronization signal, by analog addition of the code identifying the configuration identification and the synchronization signal and the TMCC synchronization signal, It is possible to reproduce a synchronization signal with lower noise than reproduction using only TMCC.

  Furthermore, as a method for checking the configuration identification portion shown in FIG. 4 in the frame extraction unit 112, the 3 bit portion from the beginning of the TMCC synchronization signal and the configuration identification portion shown in FIG. 4 of the AC carrier in the segment No. 0 It is possible to determine that emergency earthquake information has been sent to the AC when all three bits are correlated.

  The demodulated signal from the frame extraction unit 112 is output to the flag detection unit 114 and the data extraction unit 115.

  The flag detection unit 114 and the data extraction unit 115 are operated in a normal state by control signals 122 and 124, respectively. In the flag detection unit 114, the emergency earthquake warning activation flag shown in FIG. 4 is monitored in the sense shown in FIG. 5. In the initial stage, that is, the stage where no emergency earthquake warning is issued, the activation is started from “no activation signal”. The state of switching to “with signal” is monitored. At the same time, the data extraction unit 115 extracts the earthquake early warning activation flag, emergency earthquake early warning update flag, emergency earthquake early warning details, and parity bits shown in FIG. 4, and error correction of the shortened code of the differential cyclic code is performed. Each piece of extracted information is confirmed.

  The determination unit 116 and the output unit 117 are stopped by the control signals 125 and 126, respectively, at the initial stage, that is, when the emergency earthquake warning is not issued (the emergency earthquake warning activation flag is “no activation signal”).

  At the initial stage, that is, when the earthquake early warning is not issued, the demodulation / decoding unit 105, the descrambling unit 106, the demax unit 107, the decoding unit 108, the TMCC decoding unit 113, the video display unit 109, and the audio output unit 110 It is not operating.

  When an earthquake occurs and an emergency earthquake warning is issued, that is, when the emergency earthquake warning activation flag becomes “with activation signal”, the flag detection unit 114 changes from “no activation signal” to “with activation signal”. The switching state is detected, and the control signal 123 notifies the control unit 118 and the data extraction unit 115 of “the activation signal is present”, that is, the information that the emergency earthquake warning is issued. The control unit 118 receives the control signal 123, and sends signals for causing the determination unit 116 to be in a normal state and the output unit 117 to be in a standby state by the control signals 125 and 126, respectively. On the other hand, the data extraction unit 115 receives the control signal 123, and obtains the earthquake early warning update flag, emergency earthquake early warning details, and parity bit data that have been extracted and confirmed when the emergency earthquake early warning activation flag becomes “with activation signal”. The data is output to the determination unit 116.

  The discriminating unit 116 that is in the normal state by the control signal 125 receives the data from the data extracting unit 115 and performs a CRC check. Then, the signal identification shown in FIG. 7 is confirmed, and the meaning shown in FIG. Determined. Then, a preset process is performed according to each meaning, and if necessary, a control signal 127 and data are sent to the output unit 117.

  When receiving the control signal 127 from the discriminating unit 116, the output unit 117 that has been in the standby state by the control signal 126 changes from the standby state to the normal state, and further receives the data from the discriminating unit 116 to generate an emergency earthquake warning. Done.

  Detailed operations of the determination unit 116 and the output unit 117 will be described with reference to FIG.

  When the determination unit 116 determines that “EEW activation corresponding area is present”, the determination unit 116 transmits information indicating “the corresponding area is present” to the output unit 117 and also sends a control signal 127 for changing from the standby state to the normal state. In response to this, the output unit 117 receives information on “there is a corresponding area”, performs a warning by a buzzer, voice, or the like, or displays a warning by flashing light or displaying the display, and enters a normal state. At the same time, the discriminating unit 116 sends earthquake detailed information and time information such as prefectural information and epicenter information where strong shaking is expected as shown in FIG. 9 to the output unit 117, and the output unit 117 receives the earthquake early warning information. Audio output, video display, or countdown to the time when an earthquake is expected to occur.

  When the determination unit 116 determines that “EEW activation does not exist,” no control signal or data is output to the output unit 117. However, in some cases, although not shown in FIG. 1, the video display unit 109 displays earthquake details such as prefecture information and epicenter information where strong shaking is expected, or the audio output unit 110 performs audio. It may be output.

  When the discriminating unit 116 discriminates "EEW test signal applicable area present" or "EEW test signal no applicable area", this is generally effective when the emergency earthquake information receiving unit 120 is confirmed to operate in the test mode. This is ignored in the normal operation mode, and no control signal or data is output to the output unit 117. In the test mode, for example, video information or audio information indicating the test mode is multiplexed in each operation with or without the corresponding region of the EEW activation signal.

  The discriminating unit 116 always needs to confirm the signal identification when the emergency earthquake warning activation flag is “with activation signal”, but at least when the state of the emergency earthquake warning update flag changes, the identification is always confirmed. .

  The flag detection unit 114 monitors the state of switching from “with activation signal” to “without activation signal”, and when the emergency earthquake warning activation flag becomes “without activation signal”, the flag detection unit 114 A state of switching from “with activation signal” to “without activation signal” is detected, and information about “without activation signal” is transmitted to the control unit 118 and the data extraction unit 115 by the control signal 123. The control unit 118 receives the control signal 123, and sends signals for stopping the determination unit 116 and the output unit 117 according to the control signals 125 and 126, respectively. In response to this, the determination unit 116 and the output unit 117 are stopped. On the other hand, the data extraction unit 115 receives the control signal 123 and stops outputting data to the determination unit 116.

  According to the present embodiment, when the emergency earthquake warning activation flag becomes “with activation signal”, the output unit 117 is not changed from the stopped state to the normal state, but further when the signal identification is “EEW activation applicable area exists”. In the normal state, there is an effect of low power consumption in the case of “EEW activation no corresponding area” or until “EEW activation corresponding area exists” is determined from “the activation signal is present”, and When the emergency earthquake warning start flag is “with start signal” and the standby state is changed from the stop state, when the signal identification is “EEW start applicable area exists”, the normal state is quickly set and the emergency earthquake warning information is output immediately. There is an effect that can.

  Hereinafter, an embodiment of the output unit 117, which is a main block of the present invention, will be described with reference to FIG.

  1001 is input of data from the determination unit 116, 1002 is input of the control signal 127 from the determination unit 116, 1003 is input of the control signal 126 from the control unit 118, 1004 is clock unit, 1005 is current time setting unit, 1006 Is a data storage unit, 1007 is a comparison / determination unit, 1008 is a buzzer generation unit, 1009 is a processing unit, 1010 is a video display unit, and 1011 is an audio output unit.

  The clock unit 1004 always operates even when the output unit 117 is stopped, and indicates an accurate time. Use of GPS (Global Positioning System), the use of a radio clock function that automatically corrects errors by receiving standard radio waves, and the use of a function that automatically updates the correct time from the outside, such as the Internet, can be considered as methods for obtaining accurate time. Although not limited to these, it is not preferable to obtain time information from ISDB-T broadcasting for the reason described later.

  The current time setting unit 1005, the data storage unit 1006, the comparison determination unit 1007, the buzzer generation unit 1008, and the processing unit 1009 operate when the output unit 117 is in the “standby state” and the “energized state” and is in the “stop state”. Does not work.

  When the output unit 117 receives the control signal 126 from the control unit 118 via the input 1003 and enters a standby state, the current time setting unit 1005 always extracts and sets the current time from the clock unit 1004. When the discriminating unit 116 discriminates that “EEW activation corresponding region is present”, the discriminating unit 116 sends the information “the corresponding region is present” via the input 1001 of the output unit 117, and the strong shaking shown in FIG. Detailed earthquake information and time information such as prefecture information and epicenter information are sent to the output unit 117. The output unit 117 receives this and stores it in the data storage unit 1006 at the same time, and the time information is stored and simultaneously compared with the current time of the current time setting unit 1005 by the comparison determination unit 1007. The sent time information in the data storage unit 1006 is the current time information of the broadcasting station when the broadcasting station transmits, and has a predetermined accuracy. In addition to this, the processing delay on the broadcasting station side, the propagation delay of the broadcast radio wave reaching the receiver, the processing delay of the digital broadcast receiving device 121 that receives this, and the time taking into account the accuracy of the clock unit 1004, all of these are added at the maximum Since the time information in the data storage unit 1006 and the current time of the current time setting unit 1005 do not deviate beyond the positive / negative (advance / delay) of the time, the comparison judgment unit 1007 uses this as a threshold value and If it is within the value, it is determined as “normal”, and if it exceeds the threshold value, it is determined as “abnormal”. The comparison determination unit 1007 controls the buzzer generation unit 1008 to generate a buzzer when it is determined that “the area is present” and “normal”. As a result, it is possible to accumulate broadcast waves when emergency earthquake warnings have been issued in the past (hereinafter referred to as RF capture), and even when an attack such as re-transmission is received, the RF captured signal Has time information at the time of RF capture, so that the current time of the current time setting unit 1005 exceeds the threshold value and the comparison determination unit 1007 is determined to be “abnormal” and does not generate a buzzer. There is an effect that it is possible to prevent a malfunction that a buzzer is generated by the buzzer generating unit 1008. Instead of the buzzer generating unit 1008, a warning generated by voice or the like or a warning display by flashing light may be used.

  The processing unit 1009 stores time information, earthquake information such as prefecture information and epicenter information in the data storage unit 1006, and at the same time, prepares display on the video signal display unit 1010 and prepares output on the audio output unit 1011. I do. For example, although not shown in FIG. 10, the time to reach the earthquake is calculated from the installation location of the digital broadcast receiving apparatus stored in advance and the detailed earthquake information.

  The video display unit 1010 and the audio output unit 1011 operate only in the “energized state”.

  When the determination unit 116 determines that “EEW activation corresponding region exists”, the determination unit 116 receives information “presence of corresponding region” via the input 1001 of the output unit 117, prefectural information where strong shaking shown in FIG. The detailed earthquake information such as the epicenter information and the time information are sent to the output unit 117, and a control signal 127 for changing from the standby state to the normal state is sent via the input 1002. The output unit 117 receives the control signal 127 and enters a normal state.

  In a normal state, the video display unit 1010 and the audio output unit 1011 receive a signal from the processing unit 1009, and output an emergency earthquake warning audio output, video display, or a countdown until a time when an earthquake is expected to occur.

  The output unit 117 receives the control signal 126 in the stopped state from the control unit 118 via the input 1003 and enters the stopped state. That is, except for the clock unit 1004, all blocks stop operating.

  According to the embodiment of FIG. 10, it is possible to prevent malfunction of warning generation by comparing the time information with the current time.

  Further, since the buzzer is generated in the standby state, there is an effect that the buzzer can promptly notify the occurrence of the earthquake, and the power consumption can be reduced because the video display and the audio output are performed only in the normal state.

  A second embodiment according to the present invention will be described with reference to FIGS. 11 and 12.

  FIG. 11 is a block diagram showing a configuration of a digital broadcast receiving apparatus that receives emergency earthquake information transmitted using an AC signal included in segment number # 0 in the ISDB-T system, which is a Japanese terrestrial digital television broadcasting system. It is.

  Reference numeral 1101 denotes an output unit, the details of which are shown in FIG.

  The difference between the combination of FIGS. 1 and 10 and the combination of FIGS. 11 and 12 is that the video display unit 1010 and the audio output unit 1011 are shared with the video display unit 109 and the audio output unit 110, respectively.

  Therefore, the output unit 1101 in FIG. 11 has a configuration in which a video signal output 1201 and an audio signal output 1202 are provided from the processing unit 1009 as shown in FIG.

  When the emergency earthquake information receiving unit 120 is about to receive emergency earthquake information, the channel selection unit 102, the quadrature demodulation unit 103, the FFT unit 104, the synchronous reproduction unit 111, and the frame extraction unit 112 are always in operation, and the segment number 0 The AC carrier is extracted and demodulated, and the demodulated signal is output from the frame extraction unit 112 to the flag detection unit 114 and the data extraction unit 115. The operations of the channel selection unit 102, the quadrature demodulation unit 103, the FFT unit 104, the synchronous reproduction unit 111, and the frame extraction unit 112 need only be performed for segment No. 0, that is, only the one-segment part when receiving emergency earthquake information. . Thereby, it can be set as low power consumption operation | movement rather than processing the 13 segment full band of ISDB-T broadcasting.

  In addition, when the emergency earthquake information receiving unit 120 is about to receive emergency earthquake information, the control unit 118 is always operating.

  The flag detection unit 114 and the data extraction unit 115 are operated in a normal state by control signals 122 and 124, respectively. In the flag detection unit 114, the emergency earthquake warning activation flag shown in FIG. 4 is monitored in the sense shown in FIG. 5. In the initial stage, that is, the stage where no emergency earthquake warning is issued, the activation is started from “no activation signal”. The state of switching to “with signal” is monitored. At the same time, the data extraction unit 115 extracts the earthquake early warning activation flag, emergency earthquake early warning update flag, emergency earthquake early warning details, and parity bits shown in FIG. 4, and error correction of the shortened code of the differential cyclic code is performed. Each piece of extracted information is confirmed.

  The determination unit 116 and the output unit 117 are stopped by the control signals 125 and 126, respectively, at the initial stage, that is, when the emergency earthquake warning is not issued (the emergency earthquake warning activation flag is “no activation signal”).

  At the initial stage, that is, when the earthquake early warning is not issued, the demodulation / decoding unit 105, the descrambling unit 106, the demax unit 107, the decoding unit 108, the TMCC decoding unit 113, the video display unit 109, and the audio output unit 110 It is not operating.

  When an earthquake occurs and an emergency earthquake warning is issued, that is, when the emergency earthquake warning activation flag becomes “with activation signal”, the flag detection unit 114 changes from “no activation signal” to “with activation signal”. The switching state is detected, and the control signal 123 notifies the control unit 118 and the data extraction unit 115 of “the activation signal is present”, that is, the information that the emergency earthquake warning is issued. The control unit 118 receives the control signal 123, and sends a signal for causing the determination unit 116 to be in a normal state, the output unit 1101 to be in a standby state, and the broadcast receiving unit 119 to be in a standby state, according to the control signals 125, 126, and 1102, respectively. On the other hand, the data extraction unit 115 receives the control signal 123, and obtains the earthquake early warning update flag, emergency earthquake early warning details, and parity bit data that have been extracted and confirmed when the emergency earthquake early warning activation flag becomes “with activation signal”. The data is output to the determination unit 116.

  The discriminating unit 116 that is in the normal state by the control signal 125 receives the data from the data extracting unit 115 and performs a CRC check. Then, the signal identification shown in FIG. 7 is confirmed, and the meaning shown in FIG. Determined. Then, preset processing is performed according to each meaning, and if necessary, a control signal 127 and data are sent to the output unit 1101.

  When receiving the control signal 127 from the discriminating unit 116, the output unit 1101 that has been in the standby state by the control signal 126 changes from the standby state to the normal state, and receives the data from the discriminating unit 116 to generate an emergency earthquake warning. Done. At the same time, when receiving the control signal 127 from the determination unit 116, the broadcast receiving unit 119 that has been in the standby state by the control signal 1102 changes from the standby state to the normal state, and receives the video signal and audio signal from the output unit 1101. Receiving the video display unit 109 and the audio output unit 110 respectively, emergency earthquake warning is performed.

  The flag detection unit 114 monitors the state of switching from “with activation signal” to “without activation signal”, and when the emergency earthquake warning activation flag becomes “without activation signal”, the flag detection unit 114 A state of switching from “with activation signal” to “without activation signal” is detected, and information about “without activation signal” is transmitted to the control unit 118 and the data extraction unit 115 by the control signal 123. The control unit 118 receives the control signal 123, and sends signals for stopping the determination unit 116 and the output unit 1101 according to the control signals 125 and 126, respectively. In response to this, the determination unit 116 and the output unit 1101 are stopped. At the same time, the control unit 118 sends a control signal 1102 to the broadcast receiving unit 119. The broadcast receiving unit 119 receives this signal, and keeps the broadcast receiving unit 119 in a normal state for a certain period of time. The decoded video signal from the T broadcast decoding unit 108 is output to the video display unit 109, and the decoded audio signal is output to the audio output unit 110. After a predetermined time has elapsed, the broadcast receiving unit 119 is stopped. On the other hand, the data extraction unit 115 receives the control signal 123 and stops outputting data to the determination unit 116.

  Here, the stop state of the broadcast receiving unit 119 means that the channel selection unit 102, the orthogonal demodulation unit 103, the FFT unit 104, the synchronous reproduction unit 111, and the frame extraction unit 112 are in one-segment operation, and the demodulation / decoding unit 105, the descrambling unit 106, the demax unit 107, the decoding unit 108, the TMCC decoding unit 113, the video display unit 109, and the audio output unit 110 are not operating.

  The standby state of the broadcast receiving unit 119 means that the channel selection unit 102, the quadrature demodulation unit 103, the FFT unit 104, the synchronous reproduction unit 111, and the frame extraction unit 112 operate in the 13-segment full band, and the demodulation / decoding unit 105, the descrambling unit 106, the demax unit 107, the decoding unit 108, and the TMCC decoding unit 113 are operating, and the video display unit 109 and the audio output unit 110 are not operating.

  The normal state of the broadcast receiving unit 119 is that the channel selection unit 102, the quadrature demodulation unit 103, the FFT unit 104, the synchronous reproduction unit 111, and the frame extraction unit 112 operate in the 13-segment full band, and the demodulation / decoding unit 105, the descrambling unit 106, the demax unit 107, the decoding unit 108, and the TMCC decoding unit 113 are operating, and the video display unit 109 and the audio output unit 110 are operating.

  The above description is based on the assumption that the digital broadcast receiving apparatus 121 is not operating. However, the digital broadcast receiving apparatus 121 is operating, that is, the broadcast receiving unit 119 was originally in a normal state. Sometimes, the following operations are performed.

  When the emergency earthquake warning activation flag becomes “with activation signal”, the flag detection unit 114 detects a state of switching from “without activation signal” to “with activation signal”. The data extraction unit 115 is notified of “there is an activation signal”, that is, the information that the emergency earthquake warning is issued. The control unit 118 receives the control signal 123, and sends a signal for causing the determination unit 116 to be in a normal state and the output unit 1101 to be in a standby state by the control signals 125 and 126, respectively. At the same time, the control unit 118 sends a control signal 1102 to the broadcast receiving unit 119, and the broadcast receiving unit 119 receives the control signal 1102 from the decoded video signal from the decoding unit 108 to the video display unit 109 and the audio output unit 110, respectively. Preparations are made for switching from the decoded audio signal from the decoding unit 108 to the audio signal from the output unit 1101 to the video signal from the output unit 1101. On the other hand, the data extraction unit 115 receives the control signal 123, and obtains the earthquake early warning update flag, emergency earthquake early warning details, and parity bit data that have been extracted and confirmed when the emergency earthquake early warning activation flag becomes “with activation signal”. The data is output to the determination unit 116.

  The discriminating unit 116 that is in the normal state by the control signal 125 receives the data from the data extracting unit 115 and performs a CRC check. Then, the signal identification shown in FIG. 7 is confirmed, and the meaning shown in FIG. Determined. Then, preset processing is performed according to each meaning, and if necessary, a control signal 127 and data are sent to the output unit 1101.

  When receiving the control signal 127 from the discriminating unit 116, the output unit 1101 that has been in the standby state by the control signal 126 changes from the standby state to the normal state, and receives the data from the discriminating unit 116 to generate an emergency earthquake warning. Done. At the same time, when receiving the control signal 127 from the determination unit 116, the broadcast receiving unit 119 outputs the decoded video signal from the decoding unit 108 to the output unit 1101 to the video display unit 109 and the audio output unit 110, respectively. Is switched from the decoded audio signal from the decoding unit 108 to the audio signal from the output unit 1101. Then, the earthquake early warning is performed by the video display unit 109 and the audio output unit 110 by the video signal and the audio signal from the output unit 1101, respectively.

  The flag detection unit 114 monitors the state of switching from “with activation signal” to “without activation signal”, and when the emergency earthquake warning activation flag becomes “without activation signal”, the flag detection unit 114 A state of switching from “with activation signal” to “without activation signal” is detected, and information about “without activation signal” is transmitted to the control unit 118 and the data extraction unit 115 by the control signal 123. The control unit 118 receives the control signal 123, and sends signals for stopping the determination unit 116 and the output unit 1101 according to the control signals 125 and 126, respectively. In response to this, the determination unit 116 and the output unit 1101 are stopped. At the same time, the control unit 118 sends a control signal 1102 to the broadcast receiving unit 119, and the broadcast receiving unit 119 receives the control signal 1102 from the video signal from the output unit 1101 to the video display unit 109 and the audio output unit 110, respectively. Is switched from the audio signal from the output unit 1101 to the decoded audio signal from the decoding unit 108. On the other hand, the data extraction unit 115 receives the control signal 123 and stops outputting data to the determination unit 116.

  According to this embodiment, since only one video display unit and one audio output unit are required, there is an effect that the configuration can be reduced with a simple configuration as compared with the combination of FIGS. . Moreover, there is an effect that the broadcast receiving unit 119 can be automatically activated when the digital broadcast receiving apparatus 121 is not operating, and when the digital broadcast receiving apparatus 121 is operating, the emergency broadcast warning can be promptly switched. There is an effect that can be done.

DESCRIPTION OF SYMBOLS 101 ... Antenna 102 ... Channel selection part 103 ... Orthogonal demodulation part 104 ... Fast Fourier transform (FFT) part 105 ... Demodulation decoding part 106 ... Descramble part 107 ... Demax part 108 ... Decoding part 109 ... Video display part 110 ... Audio | voice output part 111 ... synchronous playback unit 112 ... frame extraction unit 113 ... TMCC decoding unit 114 ... flag detection unit 115 ... data extraction unit 116 ... determination unit 117 ... output unit 118 ... control unit 119 ... broadcast reception unit 120 ... emergency earthquake information reception unit 121 ... Digital broadcast receivers 1001, 1002, 1003 ... input 1004 ... clock unit 1005 ... current time setting unit 1006 ... data storage unit 1007 ... comparison judgment unit 1008 ... buzzer generation unit 1009 ... processing unit 1010 ... video processing unit 1011 ... audio output unit 1101 ... Output unit 1201, 1202 ... Outputs 122, 123, 12 , 125,126,127,1102 ... control signal

Claims (8)

A transmission signal having a digital broadcast signal including a video signal or an audio signal, an activation flag indicating that an emergency earthquake warning has been issued, and an emergency earthquake information signal including signal identification information indicating the content of the emergency earthquake warning A digital broadcast receiving device for receiving,
A receiver for receiving the transmission signal;
A flag detection unit that detects a start flag from an emergency earthquake information signal among transmission signals received by the reception unit;
A determination unit for determining the content of the signal identification information from the emergency earthquake information signal among the transmission signals received by the reception unit;
An output unit for outputting the content of the signal identification information determined by the determination unit;
When the activation flag detected by the flag detection unit indicates that an earthquake early warning has been issued, the device is set to the first power consumption state, and the content determined by the determination unit is being received. And a control unit that sets the apparatus to a second power consumption state higher than the first power consumption state when there is content indicating that an area where strong shaking is expected is included in the area. A digital broadcast receiver. The receiving unit includes a video / audio output unit that outputs a video signal or an audio signal of a digital broadcast signal among the received transmission signals,
The digital broadcast receiving apparatus according to claim 1, wherein the content of the signal identification information output from the output unit is output from the video / audio output unit.   The first power consumption state is a state in which the determination unit is operating and the output unit is ready for operation and does not output, and the second power consumption state is the determination unit and the output. 2. The digital broadcast receiving apparatus according to claim 1, wherein the units are in a state of operating together.   When the video / audio output unit does not output a video signal or an audio signal, the first power consumption state means that the determination unit operates, the output unit prepares for operation, and the reception 3. The state in which the unit prepares for operation and does not output, and the second power consumption state is a state in which the determination unit, the output unit, and the reception unit operate. The digital broadcast receiver described in 1.   When the video / audio output unit outputs a video signal or an audio signal, the first power consumption state is determined by the determination unit operating, the output unit preparing for operation, and the reception The second power consumption state means that the determination unit and the output unit operate, and the reception unit recognizes the video signal or the audio signal. 3. The digital broadcast receiving apparatus according to claim 2, wherein the digital broadcast receiving apparatus is in a state of being output after switching to contents.   As contents to be discriminated by the discriminating section, contents indicating that an area where strong shaking is expected is not included in the area being received, contents indicating that it is a test signal for a start test of emergency earthquake warning The digital broadcast receiving apparatus according to claim 1, wherein the digital broadcast receiving apparatus is included. The emergency earthquake information signal includes time information, regional information and epicenter information relating to the earthquake,
The discriminating unit discriminates time information, regional information and epicenter information about the earthquake from the emergency earthquake information signal among the transmission signals received by the receiving unit,
The digital broadcast receiving apparatus according to claim 1, wherein the output unit outputs time information, regional information, and epicenter information regarding the earthquake determined by the determination unit. The emergency earthquake information signal includes a notification time information when an emergency earthquake warning is issued,
The output unit is determined by a time setting unit that sets current time information, a determination unit that determines whether a difference between the current time information and the notification time information is within a predetermined range, and the determination unit. If the result is within a predetermined range, it has a warning section to notify that an emergency earthquake warning has been issued,
3. The digital broadcast receiving apparatus according to claim 1, wherein the output unit notifies that an earthquake early warning has been issued in the first power consumption state. 4.

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