JP5056400B2 - Digital receiver, control method and program - Google Patents

Description

  The present invention relates to a digital receiver, a control method, and a program that extract data of each functional channel of each frame based on channel information.

  Patent Document 1 has a configuration in which a received frame in a digital receiver includes a frame synchronization word, link information, and a low-speed information channel (paragraph 0008 and FIG. 2 of Patent Document 1) and establishes synchronization by performing synchronization processing. (Patent Document 1, paragraph 0009 and FIG. 3) are disclosed.

In Patent Document 2, in a synchronization process of a digital receiver, a correlation value between a received signal and a given frame synchronization word is calculated, and synchronization timing is determined based on the correlation value (the flowchart of FIG. 6 of Patent Document 2). ), And counting the number of error bits between the data extracted from the received signal and the data of a given frame synchronization word, and determining the synchronization timing based on the number of error bits (the flowcharts of FIGS. 4 and 7 of Patent Document 2) ) Is disclosed.
JP 2007-36975 A JP 2004-40222 A

  Data extraction from the functional channel of the frame in the digital receiver is performed based on the information of the link information channel of the frame, but when the electric field strength of the received signal is small or a large level of interference is included in the received signal This makes it difficult to detect synchronization timing and extract data from the link information channel. In such a digital receiver, in such a case, since the channel information of the frame is unknown, no functional channel data is extracted from the frame. Therefore, the received voice and received data are interrupted.

  Patent Documents 1 and 2 disclose a frame configuration and a synchronization detection method. However, when it is difficult to detect the synchronization of a frame or an error occurs in data of the link information channel, There is no mention or suggestion on how to properly extract functional channel data.

  The object of the present invention is to appropriately detect the function channel data from the corresponding frame even when the detection of the frame synchronization word is temporarily disabled or the data of the channel information detection channel temporarily becomes ineligible. It is intended to provide a digital receiver, a control method, and a program that can be extracted to suppress interruption of received voice and received data.

  According to the present invention, for a received frame in a synchronization continuation period that continues after establishment of synchronization with respect to a digitally modulated received signal, even if frame synchronization word detection is impossible, channel information detection channel data is eligible First, channel information is extracted from the channel information detection channel, and functional channel data of an ineligible frame is processed based on the channel information.

  In the present invention, even if the data of the channel information detection channel is ineligible during the synchronization duration, the channel information of the ineligible frame is determined based on the channel information applied to the past frame, and the inequality is determined based on the channel information. Process functional channel data for eligible frames.

The digital receiver of the present invention is a synchronization continuation period determining means for determining whether or not a synchronization continuation period continues after establishment of synchronization for a digital modulation reception signal, and for each frame extracted from the reception signal during the synchronization continuation period. Among them, the frame synchronization word cannot be detected or the data of the channel information detection channel is ineligible. For eligible frames, it comprises channel processing means for acquiring channel information from the data and processing the data of each functional channel of the ineligible frame based on the channel information, the data processing means comprising a channel information detection channel For ineligible frames whose data is ineligible, Determine channel information for the ineligible frame based on channel information applied to one or more previously received frames, and apply decision channel information to the ineligible frame to process data for each functional channel in the ineligible frame It is characterized by doing.

The digital receiver control method of the present invention includes a synchronization continuation period determining step for determining whether or not a synchronization continuation period continues after establishment of synchronization for a digital modulation reception signal, and each extracted from the reception signal during the synchronization continuation period. Among the frames, the frame information detection channel detecting step for detecting a frame in which the frame synchronization word cannot be detected or the channel information detection channel data is ineligible as an ineligible frame, and the channel information detection channel data is qualified. A data processing step of acquiring channel information from the data and processing data of each functional channel of the ineligible frame based on the channel information, the data processing step comprising: For ineligible frames for which detection channel data is ineligible Determines channel information of the ineligible frame based on channel information applied to one or more frames received prior to the ineligible frame, applies the determined channel information to the ineligible frame, and It is characterized by processing data of each functional channel.

  The program of the present invention causes a computer to function as each means of the above-described digital receiver of the present invention.

  According to the present invention, channel information can be applied to an ineligible frame, and functional channel data can be extracted from the ineligible frame. be able to.

  FIG. 1 is a schematic configuration diagram of a portable digital radio 10. In the reception mode period of the portable digital radio 10, radio waves from a base station or a partner machine (both not shown) are captured by the antenna 11 and converted into an RF signal. The RF signal is converted into a first stage IF signal by a first stage IF generation unit (not shown), and then converted into a second stage IF signal by a second stage IF generation unit 14. The second stage IF signal is amplified by the amplifier 15 and then converted into a digital signal by the A / D converter 16.

  The DSP 20 mounts a vocoder 21. The DSP 20 demodulates the digital signal from the A / D converter 16, extracts symbol data, and generates a reception frame. The DSP 20 extracts control information from the received frame and sends it to the microcomputer 26. The microcomputer 26 instructs the DSP 20 about various processes based on data from the DSP 20 and other data in the memory 25.

  The vocoder 21 cooperates with the codec unit 24 to reproduce an analog audio signal from audio data extracted from the frame in the reception mode period, and convert the analog audio signal to audio data in the transmission mode period. In the reception mode period, the amplifier 28 amplifies the audio signal supplied from the codec unit 24 and sends the amplified audio signal to the volume adjustment unit 29. The sound signal is adjusted in level by the volume adjusting unit 29 and then supplied to the speaker 30, converted into sound by the speaker 30, and output.

  In the transmission mode period, the user's voice is converted into an audio (electrical) signal by the microphone 35, and the audio signal is amplified by the amplifier 36 and then input to the codec unit 24. Further, the codec unit 24 and the vocoder 21 Are converted into audio data by the cooperative processing. The codec unit 24 outputs a digital modulation signal related to a frame having a predetermined configuration for storing audio data and other data, and the digital modulation signal is supplied to the voltage controlled oscillator 43 via the switch 40, the amplifier 41 and the level adjustment unit 42. Is done. The voltage control oscillator 43 generates an RF signal based on the digital modulation signal from the level adjustment unit 42, and the RF signal is transmitted from the antenna 11 by radio waves.

  FIG. 2 is a configuration diagram of a frame used in the portable digital radio 10. In FIG. 2, a frame F1 shows a general configuration of the frame. A frame synchronization word (FSW) and a link information channel (LICH) are arranged in the first and second blocks from the head of the frame, respectively, and the functional channel follows the link information channel. . The link information of the link information channel includes information related to the type of the frame (for example, frames F2 and F3 described later) as well as information related to the configuration of the frame in which the link information channel is stored. The function channel is a generic name for various channels following the link information channel, and specific examples thereof will be described in frames F2 and F3.

  In the frame F2, the low-speed information channel (SACCH) and four voice channels (VCH) follow in order as functional channels after the link information channel. In the frame F3, the front two and the rear two of the four audio channels of the frame F2 are both replaced with the high-speed information channel 1 (FACCH1). High-speed information channels 1 and 2 are also functional channels.

  When it is necessary to transmit data at high speed, the frame F3 is transmitted with the voice channel stealed and the high-speed information channel placed instead. The frame F3 may be transmitted continuously or alternately with the frame F2. For example, when two types of communication rates of 9600 bps and 4800 bps are set, voice can be transmitted in half the time of the communication period of 4800 bps in the communication period of 9600 bps. Is transmitted to.

  FIG. 3 is an explanatory diagram of the frame structure when the received radio wave is defective. In the frame F4, although the frame F2 is received, the frame synchronization word (FSW) is NG (unqualified). The detection of the frame synchronization word is performed based on the correlation value and the number of bit errors in the frame synchronization word, as will be described in detail in S51, S52, S61, and S62 of FIGS. Regarding the frame synchronization word, NG means that the frame synchronization word cannot be detected, and OK means that it is possible.

  Even in a frame in which the frame synchronization word is NG, the channel information (LICH) and the like subsequent thereto may be OK as in the frame F4. Note that the fact that the link information channel is OK and NG, respectively, means that there is no error and there is an error in the error check (error check) for the data of the link information channel. In the conventional digital receiver, if the frame synchronization word is NG, it is determined that the subsequent data such as the link information channel is not reliable and the data is not extracted. On the other hand, in the portable digital radio device 10, even if the frame synchronization word is NG, if the link information channel is OK, link information is extracted from the link information channel of the frame, Data of each functional channel of the frame is processed based on the link information.

  Frame F5 shows a case where the frame synchronization word and the link information channel are OK and NG, respectively. A frame F6 indicates a case where both the frame synchronization word and the link information channel are NG. In the case of the frames F5 and F6, since the data of the link information channel is both unknown, it is unknown what is specifically included as a functional channel. However, as will be described later, the portable digital radio 10 determines channel information of the frame by a predetermined process, and appropriately acquires functional channel data from the frame based on the channel information. Yes.

  FIG. 4 is a state transition diagram in a series of synchronization processes in the portable digital radio 10. The process of detecting the initial synchronization of the frame synchronization word is defined as “search”. Further, after synchronization is established by the search, processing that follows the frame synchronization word is defined as “link”. When synchronization is established by the search, a transition is made from the “search” state to the “link” state. If the frame synchronization word NG occurs continuously for the predetermined number of times C1 or the link information channel NG occurs continuously for the predetermined number of times C2 during the link state period, “out of synchronization” is set. The “link” state is maintained until the synchronization is lost, and when the synchronization is lost, the “link” state is changed to the “search” state.

  FIG. 5 is a flowchart of the synchronization establishment method 50 in the portable digital radio 10. In S51 of the search state period, it is determined whether the correlation processing of the frame synchronization word is OK or NG. The fact that the correlation processing of the frame synchronization word is OK means that the correlation value between the received data and the data related to the given frame synchronization word is equal to or greater than a predetermined threshold, and NG is less than the threshold. Means. If the determination in S51 is OK, the process proceeds to S52. If the determination is NG, the search state is maintained and S51 is repeated.

  In S52, it is determined whether the bit error determination of the frame synchronization word is OK or NG. If OK, the process proceeds to S53, and if it is NG, the search state is maintained and the process returns to S51. Specifically, the bit error determination of the frame synchronization word is NG if the number of error bits is greater than or equal to a predetermined threshold in the comparison between the received data and the data of a given frame synchronization word in the reception period of the frame synchronization word. If it is less than the threshold value, OK is determined. If the determinations in S51 and S52 are both OK, it is determined that synchronization in the portable digital radio 10 has been established.

  In S53, link information channel (LICH) data is acquired. In S54, based on the link information extracted from the data in S53, the configuration (channel information) of the frame including the data is grasped, and the data is extracted from each functional channel of the frame based on the configuration. After S54, the state transits to the link state.

  FIG. 6 is a flowchart of the synchronization tracking method 60 in the portable digital radio 10. The synchronization tracking method 60 is performed in synchronization with the frame period after synchronization is established in the search.

  S61 and S62 are the same processes as S51 and S52 of the synchronization establishing method 50. If both the determinations in S61 and S62 are OK, the process proceeds to S67, and if either one is NG, the process proceeds to S64. In S64, it is determined whether or not an out-of-synchronization has occurred. If the determination is positive, the process returns to the synchronization establishment method 50 (FIG. 5). If the determination is negative, the process proceeds to S67. The loss of synchronization is as described above with reference to FIG.

  In S67, data of the link information channel is acquired from the frame (hereinafter, the frame to be processed this time is appropriately referred to as “the frame”), and the process proceeds to S68. In S68, an error check is performed on the data acquired in S67. If the error check for the data is OK (no error), the process proceeds to S72, and if it is NG (error is present), the process proceeds to S73.

  The frame when proceeding from S68 to S72 includes the frame F4 of FIG. 3 in addition to the frames F2 and F3 of FIG. 2 in which both the frame synchronization word (FSW) and the link information channel (LICH) are OK. The frames when proceeding from S68 to S73 include frames F5 and F6 of FIG. In S72, the channel information extracted from the link information channel for which the data is determined to have no error is held, that is, stored in the memory.

  In contrast to S72, in S73, channel information is constructed for the frame. In this frame, the link information channel cannot be used due to an error in the link information channel. Therefore, the channel information construction for the frame in S72 is performed based on the past received frames. A specific method of constructing channel information based on past received frames will be described later with reference to FIGS.

  In S74, the configuration of the frame is grasped based on the channel information held in S72 or the channel information constructed in S73, and data is extracted from each functional channel based on the configuration.

  FIG. 7 is an explanatory diagram of channel information construction for a frame in which both the frame synchronization word and the link information channel are NG. As for the frame in which both the frame synchronization word and the link information channel are NG as shown in FIG. 7 (frame F6 in FIG. 3) and the frame in which only the link information channel is NG (frame F5 in FIG. 3), the link of the frame Channel information cannot be constructed from an information channel.

  In response to this, in the portable digital radio 10, the frame (hereinafter referred to as “frame A” as appropriate) is the same as the frame received immediately before (hereinafter referred to as “frame B” as appropriate). 6, that is, in the synchronization tracking method 60 of FIG. 6, the channel information belonging to the period in which the steps in the synchronization tracking method 60 circulate without changing to the search and applied to the frame B is voice. In the case of the channel information of the communication frame (frame F2 in FIG. 2), the frame A is also the frame F2 as in the lower frame of FIG. 7, and the channel information of the frame A is changed to the frame B (= frame F2). ) To be the same as the channel information. In the voice communication period of a general wireless device, this determination is made only when a voice communication frame (frame F2 in FIG. 2) is continuously transmitted and other types of frames are rarely used. Rely on that.

  Note that the channel information applied to the frame B is the channel information extracted from the link information channel data of the frame B itself when the error check on the link information channel data of the frame B is OK. If the error check for the data of the link information channel of frame B is NG, the channel information of frame B is the frame C received immediately before frame B (frame C is the same as frame B). Only when they belong to the same synchronization continuation period).

  FIG. 8 shows the history storage state in the internal memory 78 when the channel information of the frame whose link information channel is NG is constructed based on the history of the received frame. In the internal memory 78, the channel information [0], [1], [2],... Are applied to the frames received one, two, three,. Channel information. The internal memory 78 stores channel information applied to a total of N received frames from channel information [0] of the previous frame received to channel information [N−1] of the N previous frame. Has been.

  The channel information applied to each frame in the internal memory 78 means that the error check on the data of the link information channel of the frame is OK, and not only the channel information determined based on the data but also the link information channel of the frame The error check for the data of NG is NG, and it is determined as the channel information of the frame based on the history information of the internal memory 78 when the frame is received. As soon as the channel information of the frame is determined, the previous channel information [1], [2],... [N-2] are channel information [1], [2],. ] And the channel information of the frame are stored in channel information [0].

  A method for determining channel information of the frame based on the history of channel information will be described. When the channel information [0], [1], [2],... [N-1] are all the same (for example, the frame F2 in FIG. 2), the channel information of the frame is the same channel. Decide on information. Further, when the channel information [0], [1], [2],... [N-1] repeats the channel information of the frames F2 and F3 in FIG. The channel information is determined as channel information different from the channel information [0], that is, channel information [1].

  In determining whether the channel information of the past received frames is the same, the natural number L (2 ≦ L <N) smaller than N is set without being limited to N, and the channel information [0], [ 1],... [L-1] may be determined to be the same channel information as the channel information of the frame. Conversely, L> N may be satisfied. However, in that case, the number of channel information to be left in the internal memory 78 is set to L.

  FIG. 9 is a block diagram of the digital receiver 80. The portable digital radio 10 described above is a specific example of the digital receiver 80. The portable digital radio 10 also serves as a transmitter, but the digital receiver 80 may not have a transmission function. The digital receiver 80 may not be portable. The digital receiver 80 includes a synchronization duration determination unit 81, an ineligible frame detection unit 82, and a data processing unit 83.

  The synchronization continuation period determining means 81 determines whether or not it is a synchronization continuation period that continues after establishment of synchronization for a digital modulation reception signal. The ineligible frame detection means 82 detects, as an ineligible frame, a frame in which the frame synchronization word cannot be detected or the data of the channel information detection channel is ineligible among the frames extracted from the received signal during the synchronization duration period. . The data processing means 83 acquires channel information from the data for the ineligible frame for which the data of the channel information detection channel is qualified, and obtains the data of each functional channel of the ineligible frame based on the channel information. Process.

  A specific example of the synchronization continuation period that continues after establishment of synchronization with respect to a received signal of digital modulation is that the synchronization tracking method 60 continues to be executed without the determination of S64 being positive in the synchronization tracking method 60 (FIG. 6). It is a period. Synchronization establishment is performed in accordance with, for example, the synchronization establishment method 50 (FIG. 5). In the synchronization establishment in the synchronization establishment method 50, the correlation value determination in S51 and the bit error number determination in the frame synchronization word in S52 are both OK, but the synchronization duration determination unit 81 performs the synchronization establishment determination process. If only one of S51 and S52 is employed and the determination of one of them is OK, it can be assumed that synchronization is established.

  Specific examples of the ineligible frames are the frames 4 to 6 in FIG. A specific example of the channel information detection channel is the link information channel (LICH) of frames 1 to 3 in FIG. A specific example of the ineligible frame in which the data of the channel information detection channel is qualified is the frame 4 in FIG. The data processing of each functional channel of the ineligible frame based on the channel information in the data processing means 83 is, for example, extraction of data of each functional channel from the ineligible frame.

  The digital receiver 80 extracts the channel information from the data if the channel information detection channel data in the received frame is determined to be appropriate even if the frame synchronization word in the received frame is undetectable. Since the data of each functional channel of the received frame is processed based on the information, that is, the data that has been abandoned in the past is extracted, so that the received voice and received data are more than the conventional digital receiver. Discontinuity can be suppressed.

  Preferably, the data processing means 83 sets the channel information detection channel data for an ineligible frame based on channel information applied to one or more frames received before the ineligible frame. Channel information for the qualified frame is determined, and the determined channel information is applied to the ineligible frame to process data for each functional channel of the ineligible frame. Assume that a frame received before the ineligible frame may be either a qualifying frame (= a frame that is not an ineligible frame) or an ineligible frame. In the above-described portable digital radio device 10, as described with reference to FIGS. 7 and 8, the link information of the frame (the reception frame to be processed this time) is determined based on the link information applied to the past reception frame. . Specific examples of the ineligible frames in which the data of the channel information detection channel is ineligible are the frames F5 and F6 in FIG.

  Typically, the data processing means 83, for the ineligible frame for which the data of the channel information detection channel is ineligible, (a) the channel information applied to the frame received immediately before the ineligible frame. Determining channel information for ineligible frames, or (b) if all the channel information applied to the first predetermined number of consecutive frames including the previous received frame is the same, Whether channel information of the ineligible frame is determined for the same channel information. Then, the decision channel information is applied to the ineligible frame to process the data of each functional channel of the ineligible frame.

  The specific example of (a) has been described in relation to FIG. The frame received by the portable digital radio 10 during voice communication is only the frame 2 in FIG. 2, and based on such fact, it can be determined that the current reception frame is also a voice communication frame.

  When a digital transmitter wants to transmit data at high speed, the voice channel (VCH) may be stolen and replaced with a high-speed information channel (FACCH1). In this case, the frames with the high-speed information channel and the frames for voice communication may be alternately transmitted without continuously transmitting the frames with the high-speed information channel. In such a case, as in (a), only the channel information of the frame received immediately before the relevant frame is checked, and it is not applied to the channel information of the relevant frame as soon as possible. Thus, if the channel information of the first predetermined number of consecutive frames including the frame received immediately before the frame is the same, it is meaningful to apply the same channel information to the current frame. There is. In this case, it is necessary to examine the history of channel information of the first predetermined number of consecutive frames in the past. For this purpose, the internal memory 78 of FIG. 8 can be used.

  The data processing means 83 applies the second predetermined number of consecutive frames including the frame received immediately before the ineligible frame to the ineligible frame in which the data of the channel information detection channel is ineligible. If the channel information has periodicity, the channel information of the ineligible frame is determined based on the periodicity, and the determined channel information is applied to the ineligible frame to obtain data of each functional channel of the ineligible frame. Process.

  The second predetermined number may be the same as or different from the first predetermined number. A specific example of determining channel information based on periodicity has been described in relation to the internal memory 78 of FIG. In the description of the internal memory 78, the case where there are only two types of frames 2 and 3 in FIG. 2 and they are alternately repeated has been described. However, the periodicity handled by the data processing unit 83 includes three or more types. This includes all the periodicities in the case where there are frames and the periodicity is recognized in their reception order.

  FIG. 10 is a flowchart of the digital receiver control method 90. The digital receiver control method 90 is applied to the digital receiver 80. In S91, it is determined whether or not it is a synchronization continuation period that continues after establishment of synchronization for a digital modulation received signal. If the determination is positive, the process proceeds to S92, and if not, the digital receiver control method 90 is terminated.

  In S92, a frame in which the frame synchronization word cannot be detected or the data of the channel information detection channel is ineligible among the frames extracted from the received signal is detected as an ineligible frame. If the currently received frame is an ineligible frame, the process proceeds to S93, and if it is not an ineligible frame, the digital receiver control method 90 is terminated.

  In S93, it is determined whether or not the data of the channel information detection channel is qualified. If the determination is positive, the process proceeds to S94, and if not, the digital receiver control method 90 is terminated. In S94, channel information is acquired from the data, and in S95, the data of each functional channel of the ineligible frame is processed based on the channel information.

  The processes of S91 and S92 correspond to the functions of the synchronization duration determination means 81 and the ineligible frame detection means 82 of the digital receiver 80 (FIG. 9), respectively. The specific modes described for the functions of the synchronization duration determination unit 81 and the ineligible frame detection unit 82 can also be applied as specific modes of the processing of S91 and S92 corresponding to the digital receiver control method 90.

  The processing of S93 to S95 corresponds to the function of the data processing means 83 of the digital receiver 80. In S93 to S95, the processing related to the channel information detection channel data in the ineligible frame is performed. However, the data processing means 83 stores the channel information detection channel data in the ineligible frame. Functional steps corresponding to processing applied to the ineligible ones can be added after S93 to S95, or replaced with S93 to S95.

  The program to which the present invention is applied causes a computer to function as each unit of the digital receiver 80. Another program to which the present invention is applied causes a computer to execute each step of the digital receiver control method 90.

   This specification discloses various inventions. The invention includes not only each device and each method described in the section of the best mode of the invention, but also one or a plurality of effects and effects independent of each device and each method within the obvious range of those skilled in the art. What extracted the element, what changed one or several elements in the obvious range, and what replaced the combination of one or several elements between each apparatus and between each method are included.

It is a schematic block diagram of a portable digital radio. It is a block diagram of the frame utilized in a portable digital radio. FIG. 6 is an explanatory diagram of a frame configuration when a received radio wave is defective. It is a state transition diagram in a series of synchronous processing in a portable digital radio. It is a flowchart of the synchronization establishment method in a portable digital radio.

It is a flowchart of the synchronization tracking method in a portable digital radio. It is explanatory drawing of the channel information construction | assembly of the flame | frame in which both a frame synchronization word and a link information channel are NG. It is a figure which shows the log | history storage state in an internal memory in case the channel information of the flame | frame whose link information channel is NG is constructed | assembled based on the log | history of a received frame. It is a block diagram of a digital receiver. It is a flowchart of a digital receiver control method.

Explanation of symbols

80: digital receiver, 81: synchronization duration determination means, 82: ineligible frame detection means, 83: data processing means, 90: digital receiver control method.

Claims (5)

Synchronization duration determination means for determining whether or not the synchronization duration is continued after establishment of synchronization for a received signal of digital modulation;
Among the frames extracted from the received signal during the synchronization duration period, an ineligible frame detection means for detecting, as an ineligible frame, a frame whose frame synchronization word cannot be detected or whose channel information detection channel data is ineligible, and Data processing means for acquiring channel information from the data for the ineligible frame for which the data of the channel information detection channel is qualified, and processing the data of each functional channel of the ineligible frame based on the channel information;
Equipped with a,
For the ineligible frame in which the data of the channel information detection channel is ineligible, the data processing means determines the ineligible frame based on the channel information applied to one or more frames received before the ineligible frame. determining the channel information, the digital receiver characterized that you process the data for each function channel of said non eligible frames determined channel information is applied to said non eligible frames. The data processing means decides channel information of the ineligible frame as channel information applied to a frame received immediately before the ineligible frame for an ineligible frame for which channel data detection channel data is ineligible. Or if all the channel information applied to the first predetermined number of consecutive frames including the previous received frame is the same, the channel of the ineligible frame is included in the same channel information. However to determine information, digital receiver of claim 1, wherein the processing the data of each function channel of said non eligible frames determined channel information is applied to said non eligible frames. The data processing means is applied to a second predetermined number of consecutive frames including a frame received immediately before the ineligible frame with respect to an ineligible frame in which the data of the channel information detection channel is ineligible. If the channel information has periodicity, the channel information of the ineligible frame is determined based on the periodicity, and the determined channel information is applied to the ineligible frame to obtain data of each functional channel of the ineligible frame. The digital receiver according to claim 1 , wherein the digital receiver performs processing. A synchronization duration determination step for determining whether or not the synchronization duration is continued after establishment of synchronization with respect to a received signal of digital modulation;
An ineligible frame detection step of detecting, as an ineligible frame, a frame in which the frame synchronization word cannot be detected or the data of the channel information detection channel is ineligible among the frames extracted from the received signal during the synchronization duration; and For an ineligible frame for which data of a channel information detection channel is qualified, a data processing step of obtaining channel information from the data and processing data of each functional channel of the ineligible frame based on the channel information;
Equipped with a,
In the data processing step, for an ineligible frame in which the data of the channel information detection channel is ineligible, the ineligible frame is determined based on channel information applied to one or more frames received before the ineligible frame. determining the channel information, the digital receiver control method applied, it characterized that you process the data for each function channel of said non eligible frames determined channel information to said non eligible frames. The program which makes a computer function as each means of the digital receiver in any one of Claims 1-3 .

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