JP2008193385A - Digital broadcast receiver, reception method, and program for the receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital broadcast receiver, a reception method, and a program for the receiver, capable of stably receiving a digital broadcast even in the fringe area of an MFN for a digital terrestrial broadcast. <P>SOLUTION: The digital broadcast receiver 3 is arranged in an MFN fringe area where the weak electric field reception area of a relay station 1 is superimposed on the weak electric field reception area of a relay station 2. Even when the broadcast wave of the relay stations 1, 2 cannot be stably received as a result of scanning the broadcast wave in arrangement, the digital broadcast receiver 3 receives either wave of the relay stations 1, 2 when the broadcast wave is receivable to some extent. The reception states of the broadcast wave of the relay stations 1, 2 are monitored, and then, the broadcast wave is received by the reception method corresponding to the combination of the reception states of respective channels. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a digital broadcast receiver, a receiving method, and a program for the receiver.

  In digital terrestrial broadcasting, a relay station is being constructed to provide stable fixed reception to all households. Some areas built with Multi Frequency Network can receive radio waves from multiple transmitters / relay stations with a low electric field / low CN ratio, but due to the low electric field / low CN ratio, there are areas where stable fixed reception is not possible. is there. In such a case, it was necessary to construct a small relay station for this area and to transmit by cable.

In addition, when a receiver is set in the above-mentioned Multi Frequency Network fringe area, there are a plurality of channel numbers (frequency) corresponding to each receivable channel (relay station). A receiver is also proposed in which one is selected or a plurality of physical channels are assigned to the list of receivable channels, and the reception channel is determined after confirming the reception status of each channel corresponding to the broadcast station selected at the time of viewing. (For example, paragraph 0058 of Patent Document 1).
JP-A-2005-318152

  However, for such an area, construction of a relay station and transmission by a cable cost enormous costs. On the other hand, there is a high demand for stable fixed reception in such an area.

  The receiver described in Patent Document 1 selects only one channel having the best reception status in the Multi Frequency Network, and the selected channel is also originally received with a low electric field / low CN ratio. Since this is an area that can only be used, stable reception cannot be expected.

  Accordingly, the present invention has been invented in view of the above problems, and its purpose is to provide a digital broadcast receiver capable of stable reception even in the MFN fringe area of terrestrial digital broadcast, a reception method, and a program for the receiver. Is to provide.

  The present invention for solving the above-mentioned problems is a receiver for digital broadcasting, in which a combination of reception statuses of channels capable of receiving the same broadcast program and a reception method at the time of the combination are stored in association with each other Means for detecting the reception status of each channel, and a reception method corresponding to the combination of the reception status of each channel detected by the reception status detection means is selected from the storage means, and the selected reception method is selected. And receiving means for receiving broadcast waves.

  The present invention for solving the above-mentioned problems is a digital broadcast receiver, a channel detection means for detecting a channel of a Multi Frequency Network, a means for detecting the reception status of each detected channel, and the detected Receiving means for receiving a broadcast wave in a diversity scheme based on a combination of channels according to the reception status of each channel.

  The present invention that solves the above-described problems is a digital broadcast receiver that includes at least one or more antennas, a plurality of tuners that receive each channel of the Multi Frequency Network, and a combination of the antennas and the plurality of tuners. Means for detecting the reception status of each channel of the Multi Frequency Network in the receiver, and receiving a broadcast wave by a diversity method using a combination of the antenna and the plurality of tuners according to the detected reception status of each channel Means.

  The present invention for solving the above-described problems is a digital broadcast receiving method, which receives each channel of a Multi Frequency Network, detects the reception status of each channel, and broadcasts based on the detected reception status of each channel. A wave receiving method is selected and received.

  The present invention for solving the above-described problems is a program for a digital broadcast receiver, which is a channel detection process for detecting receivable channels constituting the Multi Frequency Network, and monitoring for monitoring the reception status of each channel of the Multi Frequency Network. A program for causing a digital broadcast receiver to execute a process and a reception process of selecting and receiving a broadcast wave reception method based on a reception state of each channel.

  The present invention can provide a digital broadcast receiver, a reception method, and a program for the receiver capable of stable reception even in the MFN fringe area of digital terrestrial broadcasting. The reason is that a stable CN ratio with no temporal variation is ensured by receiving a physical channel of a relay station that constitutes an MFN that cannot be stably received and receiving diversity.

  An embodiment of the present invention will be described.

  FIG. 1 is a diagram for explaining the concept of the present invention.

  In FIG. 1, 1 and 2 are relay stations, and 3 is a digital broadcast receiver capable of receiving broadcast waves from the relay stations 1 and 2.

  The relay stations 1 and 2 are relay stations constituting a Multi Frequency Network (hereinafter referred to as MFN), which relay broadcast waves of the same TS (same program) but having different frequencies (physical channels). is there. In FIG. 1, a solid circle indicates a strong electric field area, and a dotted circle indicates a weak electric field area.

  The digital broadcast receiver 3 is installed at a position where the weak electric field receiving area of the relay station 1 and the weak electric field receiving area of the relay station 2 overlap (MFN fringe area), and can receive the broadcast waves of the relay stations 1 and 2. Digital broadcast receiver. However, since the digital broadcast receiver is installed at the position where the weak electric field receiving area of the relay station 1 and the weak electric field receiving area of the relay station 2 overlap (MFN fringe area), the broadcast wave of any relay station is stable. Cannot be received. Even under such circumstances, conventionally, a digital broadcast receiver scans a broadcast wave at the time of installation, selects a channel (frequency) of one of the relay stations 1 and 2, and broadcasts the relay station. You will receive waves.

  However, if the digital broadcast receiver 3 of the present invention is capable of receiving a certain amount of broadcast waves from the relay stations 1 and 2 as a result of performing a scan of the broadcast waves at the time of installation, the digital broadcast receiver 3 can receive it to some extent. Both broadcast waves of the relay stations 1 and 2 are received. Then, the broadcast wave reception status of the relay stations 1 and 2 is monitored, and the broadcast wave is received by a reception method corresponding to the combination of the reception status of each channel. As a typical reception method, diversity reception by a combination of broadcast waves of relay stations 1 and 2 or, if either of relay stations 1 and 2 cannot receive, broadcast waves of receivable relay stations are received. There is diversity reception used.

  As described above, according to the present invention, when performing channel scanning, a channel that cannot be stably received is also received, and in normal reception, diversity reception using a receivable channel is performed, so that time is improved. A stable CN ratio without fluctuation is ensured.

  Next, the digital broadcast receiver in this embodiment will be described.

  FIG. 2 is a block diagram of the digital broadcast receiver 3.

Digital broadcast receiver 3 in this embodiment includes an antenna ₁₁ 1, 11 _2, a tuner ₁₂ 1, 12 _2, a demodulator ₁₃ 1, 13 _2, and the coefficient setting unit ₁₄ 1, 14 _2, signal combining unit 15 and a control unit 16.

The tuners 12 ₁ and 12 ₂ scan the receivable relay stations constituting the MFN while changing the reception channel by the control unit 16 when the digital broadcast receiver is installed. After scanning, the control unit 16 changes the frequency to a receivable channel frequency.

Demodulation unit ₁₃ 1, 13 _2, demodulates the received signal from the tuner ₁₂ 1, 12 _2, and outputs the demodulated signal to the coefficient setting unit ₁₄ 1, 14 _2.

The coefficient setting units 14 ₁ and 14 ₂ perform weighting instructed from the control unit 16 on the demodulated signal, and output it to the signal synthesis unit 15.

The signal synthesis unit 15 synthesizes the demodulated signals (weighted) output from the coefficient setting units 14 ₁ and 14 ₂ and outputs the synthesized signals to a decoding unit (not shown) at the subsequent stage of the receiver.

The control unit 16 acquires the frequency information of the relay stations constituting the MFN from the received TS of any channel from the Network Information Table (hereinafter referred to as NIT). FIG. 3 is a diagram showing an example of NIT information. In the NIT information shown in FIG. 3, five relay stations having a frequency of 545.142857 MHz, a frequency of 593.142857 MHz, a frequency of 479.142857 MHz, a frequency of 599.142857 MHz, and a frequency of 509.142857 MHz are MFNs. I understand that. Then, the control unit 16 sets the frequencies of these MFN relay stations in the tuners 12 ₁ and 12 ₂ to detect the reception status. The detection method is based on the signal level of the demodulated signals from the demodulation units 13 ₁ and 13 ₂ , the error rate, and the like. When a receivable relay station is detected, the control unit 16 stores the channel (frequency) of the relay station.

Further, the control unit 16 stores a table of broadcast wave reception methods, and controls the reception frequencies of the tuners 12 ₁ and 12 ₂ based on diversity reception corresponding to the reception status detected at the time of actual reception. The weighting coefficients of the coefficient setting units 14 ₁ and 14 ₂ are controlled.

  Next, a specific operation of the digital broadcast receiver 3 having the above configuration will be described. In the following description, it is assumed that the digital broadcast receiver 3 is installed at a position as shown in FIG. 1 and can receive 25CH and 33CH.

First, the digital broadcast receiver 3 scans a relay station that can be received at the time of installation, acquires the physical channel (frequency) of the relay station that constitutes the MFN from the NIT of the received broadcast wave, and based on this, While changing the reception channels of the tuners 12 ₁ and 12 _2, the relay stations that can be received are specified.

  FIG. 4 is a diagram showing a state when the digital broadcast receiver 3 is scanned. In FIG. 4, the digital broadcast receiver 3 scans from the lowest channel (frequency) to the higher one, such as “25CH, 26CH, 27CH,..., 33CH, 34CH, 35CH,. It can be seen that the receivable channels are “25CH, 27CH,..., 33CH, 34CH,. Furthermore, the physical channel of the relay station that constitutes the MFN can be identified from the NIT of the channel of the relay station that constitutes the MFN. In the example of FIG. 4, 25CH and 33CH are MFN channels for the broadcaster A, and 27CH and 34CH are MFN channels for the broadcaster B.

  Next, when the digital broadcast receiver 3 finds a relay station that can be received by each broadcaster, a reception method table as shown in FIG. 5 is created in the control unit 16 for each broadcaster. FIG. 5 is an example of a reception method table in the case where the broadcaster A can receive a relay station of 25CH and 33CH.

  In the reception table shown in FIG. 5, reception patterns from reception pattern 1 to reception pattern 9 are defined, and this reception pattern is a pattern of a reception method corresponding to the reception situation of each relay station that varies with the passage of time. is there.

  In the reception pattern 1, when the reception status of the reception channel 25CH is “good” and the reception status of the reception channel 33CH is “good”, the reception method in this case is a diversity method using the reception channels 25CH and 33CH. This is a pattern for receiving.

  In the reception pattern 2, when the reception state of the reception channel 25CH is “good” and the reception state of the reception channel 33CH is “normal”, the reception method in this case is a diversity method using the reception channels 25CH and 33CH. This is a pattern for receiving.

  In the reception pattern 3, when the reception status of the reception channel 25CH is “good” and the reception status of the reception channel 33CH is “impossible”, the reception method in that case is reception by a diversity method using the reception channel 25CH. It is a pattern.

  In the reception pattern 4, when the reception status of the reception channel 25CH is “normal” and the reception status of the reception channel 33CH is “good”, the reception method in this case is a diversity method using the reception channels 25CH and 33CH. This is a pattern for receiving.

  In the reception pattern 5, when the reception status of the reception channel 25CH is “normal” and the reception status of the reception channel 33CH is “normal”, the reception method in this case is a diversity method using the reception channels 25CH and 33CH. This is a pattern for receiving.

  In the reception pattern 6, when the reception status of the reception channel 25CH is “normal” and the reception status of the reception channel 33CH is “impossible”, the reception method in that case is reception by a diversity method using the reception channel 25CH. It is a pattern.

  In the reception pattern 7, when the reception state of the reception channel 25CH is “impossible” and the reception state of the reception channel 33CH is “good”, the reception method in that case is received by the diversity method using the reception channel 33CH. It is a pattern.

  In the reception pattern 8, when the reception status of the reception channel 25CH is “impossible” and the reception status of the reception channel 33CH is “normal”, the reception method in this case performs reception by a diversity method using the reception channel 33CH. It is a pattern.

  The reception pattern 9 is a pattern that cannot be received when the reception status of the reception channel 25CH is “impossible” and the reception status of the reception channel 33CH is “impossible”.

  The reception pattern of the reception method table is created in advance and stored in the control unit 16 except for receivable channels, and the receivable channels are written based on the scan result at the time of installation.

Next, normal reception operation will be described. In the following description, in the initial state, the tuner 12 ₁ receives the 25ch, tuner 12 ₂ is assumed to receive the 33CH.

In the normal reception, the control unit 16 monitors the reception status of each channel at predetermined time intervals from the signal level, etc. of the demodulated signal from the demodulator 13 _1, 13 _2. Then, a reception pattern corresponding to the reception status of each channel at that time is selected from the reception table, and weighting coefficient control based on the reception method is performed on the coefficient setting units 14 ₁ and 14 ₂ . For example, when the reception status of the reception channel 25CH is “good” and the reception status of the reception channel 33CH is “good”, the reception pattern 1 is selected, and reception is performed by a diversity method using 25CH and 33CH. . In this case, the weighting coefficient is controlled by, for example, maximum ratio combining for each carrier.

The reception state of the reception channel 25CH is the "not", and selects the reception pattern 7 when the reception state of the reception channel 33CH is "good", and change the reception channel of the tuner 12 ₁ from 25CH to 33CH the 33CH, receives the 33CH in diversity with two systems by the tuner 12 ₁ and the tuner 12 _2. In this case, the weighting coefficient is controlled by, for example, maximum ratio combining for each carrier.

  As described above, by selecting and receiving a reception method according to the reception status of each channel, stable reception is possible even in the MFN fringe area.

  In the present embodiment, two receivable relay stations have been described. However, the present invention is not limited to this, and two or more relay stations may be used. In this case, the present invention can be applied by increasing the number of tuners according to the number of relay stations that can be received.

  Moreover, although this Embodiment demonstrated the example of the diversity reception by the maximum ratio synthesis | combination for every carrier, it is not restricted to this. For example, diversity reception may be performed for TS.

  Further, the reception status may be detected not only by the signal level but also by the CN ratio, error rate, and the like.

  Further, the detection of the relay stations constituting the MFN is not limited to NIT, and detection may be performed at the TS level.

  Furthermore, the reception pattern may be increased by a combination of an antenna and a tuner.

FIG. 1 is a diagram for explaining the concept of the present invention. FIG. 2 is a block diagram of the digital broadcast receiver 3. FIG. 3 is an example of NIT information. FIG. 4 is a diagram showing an example of scanning by the digital broadcast receiver 3. FIG. 5 is an example of a reception method table.

Explanation of symbols

1, 2 relay station 3 digital broadcast receiver 11 ₁ , 11 ₂ antenna 12 ₁ , 12 ₂ tuner 13 ₁ , 13 ₂ demodulator 14 ₁ , 14 ₂ coefficient setting unit 15 signal synthesizer 16 controller

Claims (16)

A digital broadcast receiver,
A storage means for storing a combination of reception statuses of channels capable of receiving the same broadcast program and a reception method at the time of the combination;
Reception status detection means for detecting the reception status of each channel;
Receiving means for selecting from the storage means a reception method corresponding to a combination of reception statuses of the respective channels detected by the reception status detection means, and receiving means for receiving broadcast waves by the selected reception method. Receiving machine.   2. The receiver according to claim 1, further comprising: a channel registration unit that detects a channel capable of receiving the same program and registers the channel in the storage unit.   3. The receiver according to claim 2, wherein the channel registration means is configured to detect a receivable channel of the same program based on the Network Information Table.   The receiver according to any one of claims 1 to 3, wherein the receiving means performs reception by a diversity method using a plurality of channels. A digital broadcast receiver,
Channel detection means for detecting channels of the Multi Frequency Network;
Means for detecting the reception status of each detected channel;
And a receiver for receiving a broadcast wave in a diversity scheme based on a combination of channels according to the detected reception status of each channel.   6. The receiver according to claim 5, wherein the channel detection means is configured to detect a channel of the Multi Frequency Network based on the Network Information Table. A digital broadcast receiver,
At least one or more antennas;
Multiple tuners that receive each channel of the Multi Frequency Network,
Means for detecting the reception status of each channel of the Multi Frequency Network when the antenna and the plurality of tuners are combined;
A receiver comprising: a receiving unit configured to receive a broadcast wave by a diversity method using a combination of the antenna and the plurality of tuners according to the detected reception state of each channel.   8. The receiver according to claim 7, further comprising channel detection means for detecting a channel of the Multi Frequency Network based on the Network Information Table. A method for receiving digital broadcasting,
Receive each channel of Multi Frequency Network,
Detect the reception status of each channel,
A method for receiving a digital broadcast, comprising: selecting a reception method of a broadcast wave based on the detected reception status of each channel.   The digital broadcast receiving method according to claim 9, wherein a broadcast wave is received by a diversity method based on a combination of reception states of the respective channels.   11. The digital broadcast receiving method according to claim 9, wherein a channel of the Multi Frequency Network is detected based on the Network Information Table.   The digital broadcast receiving method according to any one of claims 9 to 11, wherein a combination of reception states of the channels and a receiving method at the time of the combination are set in advance. A program for a digital broadcast receiver,
Channel detection processing for detecting receivable channels constituting the Multi Frequency Network;
A monitoring process for monitoring the reception status of each channel of the Multi Frequency Network;
A program that causes a digital broadcast receiver to execute reception processing for selecting and receiving a broadcast wave reception method based on the reception status of each channel.   The program according to claim 13, wherein the reception process is a process of receiving a broadcast wave by a diversity method based on a combination of channels according to a reception situation of each channel.   The program according to claim 13 or 14, wherein the channel detection processing detects a channel of a Multi Frequency Network based on a Network Information Table. The program according to any one of claims 13 to 15, further comprising a process of previously storing a combination of reception states of the channels and a reception method at the time of the combination.

Images