JP2007251413A - Method and apparatus for confirming receivable broadcast channel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a total channel scanning time with a reduced number of channels for confirming receivability, by omitting receivability confirmation operation of an unnecessary channel. <P>SOLUTION: When confirming receivability of a receiving channel presence of at least one channel adjacent thereto is decided. When no adjacent channel is present, the receivability confirmation process with regard to the adjacent channel concerned is skipped. The presence of the adjacent channel is decided from the magnitude of the control variable for the amplifier amplifying a receiving signal. The presence of the adjacent channel may be decided in regard to either both adjacent channels on the upper side and the lower side of the receiving channel of interest, on which receivability is to be confirmed, or may be decided in regard to an adjacent channel on one side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a broadcast receivable channel confirmation method and apparatus for sequentially confirming whether each channel is receivable.

  In a broadcast receiver, generally, before starting viewing, information on channels that can be received at the place where the broadcast receiver is installed is set in the receiver. As a method for this, there is a general method of confirming reception of all channels in sequence, called channel scan, and setting channel list information determined to be receivable in the receiver.

  Also, there is provided search channel selection means for confirming reception of channels in order and viewing the channel as it is on a channel where receivable broadcasting is found, or means for registering a channel that can be received by search channel selection to a preset button. There are also broadcast receivers.

  However, in channel scanning and search channel selection, it takes a lot of time to confirm reception for a plurality of channels. In addition, in a terrestrial digital broadcast receiver, it takes time for OFDM (orthogonal wave frequency division multiplexing) frame synchronization, which takes more time than analog broadcasting.

  In particular, a receiver that performs channel scanning with a broadcast receiver that can be used at the time of moving to set receivable channel information performs channel scanning even when the receivable channel changes due to movement, so it is as fast as possible. It is desirable to perform a channel scan.

  As a means for speeding up channel scanning, for example, as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2004-112079), two tuners are mounted, and two tuners simultaneously confirm whether reception is possible in reverse order. A way to go is proposed. In this method, the channel scan time can be reduced to about half, but it may not be possible to mount the two tuners on the receiver due to the mounting area and power consumption. In addition, since reception confirmation is performed for all channels, there is room for further speedup.

  Separately from this, in Patent Document 2 (Japanese Patent Laid-Open No. 10-210384), the program of the channel currently being viewed by the user is normally displayed from the first tuner, but the scan button on the remote control is displayed. Discloses a technique in which the channel scan mode is set when the button is pressed, a two-screen display is performed, and the channels are sequentially scanned using the second tuner in parallel with the program of the channel currently being viewed by the user. Has been.

However, this does not speed up the channel scanning by simply providing a channel scanning tuner and simply scanning in parallel with the screen being viewed.
JP 2004-112079 A JP-A-10-210384

  SUMMARY OF THE INVENTION An object of the present invention is to reduce the number of channels for performing reception acceptability confirmation by omitting an operation for confirming whether or not unnecessary channels can be received, thereby shortening the total channel scan time.

  The present invention according to claim 1 is a broadcast receivable channel in which, for a reception channel received by a broadcast receiver, reception acceptance confirmation as to whether or not the reception channel is receivable is performed while changing a target reception channel. In the confirmation method, when confirming whether or not the reception channel can be received, it is determined whether or not there is at least one adjacent channel adjacent to the reception channel. If there is no adjacent channel, the reception permission confirmation step for the adjacent channel is skipped. It is characterized by that.

  The invention according to claim 2 determines the presence / absence of the adjacent channel in the above-mentioned adjacent channels on both the upper side and the lower side with respect to the reception channel that is the reception possibility confirmation target.

  The invention according to claim 3 determines the presence / absence of the adjacent channel in only the adjacent channel on one side of the upper side or the lower side with respect to the reception channel that is the reception possibility confirmation target.

  In the invention according to claim 4, confirmation of whether or not the reception channel can be received and determination of the presence or absence of the adjacent channel are skipped every several channels.

  According to the fifth aspect of the present invention, the pass band of the band pass filter is widened to increase the number of channels for determining whether there is an adjacent channel.

  In the invention according to claim 6, when determining the presence or absence of an adjacent channel, the pass band of the band pass filter is widened, and when the determination result is that there is an adjacent channel, the pass band is narrowed and reception is confirmed.

  According to the seventh aspect of the present invention, the presence / absence of the adjacent channel is determined based on the control amount of the amplifier that amplifies the received signal.

  The present invention according to claim 8 is a reception availability confirmation means for confirming whether or not the reception channel is receivable with respect to the reception channel received by the broadcast receiver while changing the target reception channel. In the broadcast receivable channel confirmation device, the reception possibility confirmation means comprises an adjacent channel presence / absence judgment means for judging the presence / absence of at least one adjacent channel adjacent to the reception channel for which reception acceptance confirmation is performed, When the determination result is that there is no adjacent channel, the reception availability confirmation unit skips the reception availability confirmation for the adjacent channel.

  According to the ninth aspect of the present invention, in the broadcast receivable channel confirmation device, the adjacent channel presence / absence judging means determines the presence / absence of the adjacent channel on both the upper side and the lower side with respect to the reception channel that is the reception possibility confirmation target. Judge for adjacent channels.

  According to the tenth aspect of the present invention, in the broadcast receivable channel confirmation device, the adjacent channel presence / absence judging means judges only the adjacent channel on the upper side or the lower side with respect to the reception channel that is the reception possibility confirmation target. To do.

  According to an eleventh aspect of the present invention, in the broadcast receivable channel confirmation device, the reception availability confirmation means and the adjacent channel presence / absence judgment means determine whether or not the reception channel can be received and determine whether there is an adjacent channel every several channels. To skip.

  According to a twelfth aspect of the present invention, the broadcast receivable channel confirmation device further includes pass band varying means for varying the pass band of the band pass filter, and the adjacent channel presence / absence judging means is passed by the pass band varying means. The number of adjacent channels to be determined is changed according to the change in bandwidth.

  According to the thirteenth aspect of the present invention, when the reception availability checking means determines the presence or absence of an adjacent channel, the passband variable means widens the passband of the bandpass filter, and passes when the determination result is that there is an adjacent channel. Narrows the bandwidth and confirms whether or not reception is possible.

  In the invention according to claim 14, the adjacent channel presence / absence determining means determines the presence / absence of an adjacent channel from the control amount of the amplifier that amplifies the received signal.

  According to the fifteenth aspect of the present invention, the adjacent channel presence / absence determining means is incorporated in a channel scan broadcast receiving unit that is different from the normal reception broadcast receiving unit that performs a normal reception operation.

  According to the present invention, if there is no adjacent channel adjacent to the reception channel that is the reception availability confirmation target, the reception availability confirmation operation for the adjacent channel is omitted. Can reduce the number of channels to be executed and shorten the total channel scan time.

  According to the second and ninth aspects of the invention, the presence / absence of adjacent channels is determined for both the upper side and the lower side of the reception channel that is a reception availability confirmation target. The number can be further reduced.

  According to the third and tenth aspects of the present invention, since the presence / absence of the adjacent channel is determined only for the adjacent channel on the upper side or the lower side with respect to the reception channel that is the reception confirmation target, Confirmation time can be further shortened.

  According to the fourth and eleventh aspects of the present invention, confirmation of whether or not the reception channel is received and determination of the presence or absence of the adjacent channel are skipped every several channels, so that the total channel scan time can be further shortened.

  According to the fifth and twelfth aspects of the present invention, since the number of channels for determining the presence / absence of adjacent channels is increased / decreased by increasing / decreasing the passband of the bandpass filter, the number of channels for confirming whether reception is possible can be adjusted. .

  According to the inventions according to claims 6 and 13, when judging the presence or absence of an adjacent channel, the pass band of the band pass filter is widened, and when the judgment result is that there is an adjacent channel, the pass band is narrowed and received. Since the availability confirmation is performed, the number of channels on which the reception availability confirmation is performed can be reduced, and at the same time, the detailed reception availability confirmation can be performed.

  According to the seventh and fourteenth aspects of the present invention, the presence / absence of an adjacent channel can be easily determined from the control amount of the amplifier that amplifies the received signal.

  According to the fifteenth aspect of the present invention, the adjacent channel presence / absence determining means is incorporated in the channel scan broadcast receiving unit different from the normal reception broadcast receiving unit that performs the normal reception operation. The present invention can be realized by adding a dedicated channel scan broadcast receiver to the receiver.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a broadcast receiver 10 to which the present invention is applied.
A signal received by the antenna 11 is input to the broadcast receiving unit 12. The broadcast receiving unit 12 receives and demodulates a signal having a frequency corresponding to the channel designated by the control unit 14. The control unit 14 is a part that performs overall control processing in the broadcast receiver 10 such as reception control, decoding of received data (video, audio, etc.) and display control. The reception data output from the broadcast receiving unit 12 is decoded by the control unit 14 into video, audio, etc., displayed on the display unit 15, and presented to the audio presentation unit 16. The key input unit 13 is a part that receives instructions regarding broadcast reception from the user such as channel setting, and the input information is input to the control unit 14 and used for reception control and display control. The scan result holding unit 17 is a part that holds receivable channel information, which is a result of channel scanning.

A configuration example of the broadcast receiving unit 12 in terrestrial digital broadcasting is shown in FIG.
A signal received by the antenna 11 is first input to an RF side band pass filter (BPF) 20, amplified by an RF side amplifier circuit (RF-AMP) 21, and input to a mixing circuit 22. The mixing circuit 22 converts the output of the amplification circuit (RF-AMP) 21 on the RF side to the intermediate frequency by mixing with the signal of the local oscillation circuit (OSC) 26. The frequency of the local transmission circuit 26 is controlled by an automatic gain control unit (AGC control unit) 27 so that a signal having a tuning frequency designated by the control unit 14 is converted into an intermediate frequency.

  Next, the IF side band pass filter (BPF) 23 removes unnecessary frequency signals such as adjacent channels from the output of the mixing circuit 22 and takes out only the signal in the selected frequency band, and the IF side amplification circuit. (IF-AMP) 24 amplifies to a voltage level that can be input to OFDM demodulation circuit 25. This is OFDM demodulated by the OFDM demodulating circuit 25 and the received data is taken out. The gains of the RF side amplifier circuit (RF-AMP) 21 and the IF side amplifier circuit (IF-AMP) 24 are variable, and the gain control signal from the AGC control unit 27 is set so as to have a voltage level required in the subsequent stage. That is, the RF side amplifier circuit (RF-AMP) 21 is controlled by the RF-AGC signal, and the IF side amplifier circuit (IF-AMP) 24 is controlled by the IF-AGC signal.

  In such a broadcast receiving unit 12, the pass band of the RF side band pass filter (BPF) 20 overlaps the selected channel and a part of its adjacent channel, and the IF side band pass filter (BPF). The pass band of 23 is configured to be only the selected channel.

An example of the operation in the broadcast receiving unit 12 at that time is shown in FIG.
In the case of FIG. 5A, the signal strength is determined to be stronger than the original signal strength due to the influence of the adjacent channel, and the amplification amount in the RF side amplifier circuit 21 becomes small. As a result, since the signal strength of the target channel does not reach the required strength, the IF side amplifier circuit 24 amplifies the signal strength to the required strength, and the amount of control here increases.

  In the case of FIG. 5B, the signal strength is determined to be stronger than the original signal strength due to the influence of the adjacent channel, and the RF side amplifier circuit 21 performs the operation of reducing the strength. As a result, since the signal intensity of the required channel does not reach the required intensity, the IF side amplifier circuit 24 amplifies the required intensity, and the amount of control here increases.

  In the case of FIG. 5C, since there is no adjacent channel, appropriate gain control is performed in the RF side amplifier circuit 21, and the control amount in the IF side amplifier circuit 24 becomes small.

  FIG. 4D shows the case where the intensity of the input signal is very small, and even if it is amplified to the maximum by the RF side amplifier circuit 21, it does not reach the required strength, so that it is further amplified by the IF side amplifier circuit 24. become.

  In this way, when there is no adjacent channel and the voltage can be amplified to the OFDM demodulator 25 only by the RF side amplifier circuit 21, the control amount in the IF side amplifier circuit 24 becomes small. If the level of the input signal is far from the voltage that can be input to the OFDM demodulator 25 and it is not sufficient to amplify (or reduce) the maximum control amount in the RF-side amplifier circuit 21, the IF-side amplifier circuit The amount of control at 24 increases.

  On the other hand, when there is an adjacent channel, the RF-side amplifier circuit 21 determines that the electric field strength of the channel to be originally received is larger due to the influence of the adjacent channel, and the output level of the RF-side amplifier circuit 21 is higher than the original. Control to make it smaller. For this reason, the IF-side amplifier circuit 24 performs control such that the amount that cannot be controlled by the RF-side amplifier circuit 21 is amplified, so that the control amount of the IF-side amplifier circuit 24 increases.

  In the present invention, from the magnitude of the control amount (RF-AGC, IF-AGC) of each amplifier circuit (RF-AMP, IF-AMP), when confirming reception of a certain channel, the presence / absence of an adjacent channel is simultaneously determined. The adjacent channel presence / absence determining means added to the broadcast receiving unit 12 determines the information and passes the presence / absence information to the control unit 14 as a reception status. When this information is used for channel scanning and there is no adjacent channel, the adjacent channel Skip the reception acceptability confirmation process for.

FIG. 4 shows the operation flow of the first embodiment.
Assume that the channel number to be scanned is from channel a to channel b.

  First, the channel k to be confirmed for reception first is the (a + 1) channel (step S1), and it is confirmed whether it is a receivable channel and the presence / absence of an adjacent channel (step S2). The k channel reception confirmation result received from the broadcast receiving unit 12 is stored in the scan result holding unit 17 (step S3). The broadcast receiving unit 12 determines whether there is an adjacent channel (step S4). If it is determined that there is an adjacent channel, (k-1) channel reception confirmation is performed (step S5), and the result is the scan result. The data is stored in the holding unit 17 (step S6), and 2 is added to the next reception confirmation channel k (step S7).

  On the other hand, if it is determined that there is no adjacent channel, “no broadcast” is stored in the scan result holding unit 17 of the (k−1) channel and the (k + 1) channel (steps S8 and S9), and the next reception confirmation is performed. 3 is added to the channel k (step S10).

  By repeating this, it is determined whether or not the reception confirmation channel k is equal to or more than the b channel (step S11), and if so, then it is determined whether or not k = b + 1 (step S12). The reception confirmation of the b channel is performed (step S13), the presence / absence (reception availability) is stored (step S14), and the scan is terminated.

  FIG. 5 shows an example of the reception result stored in the scan result holding unit 17 when scanning is performed in the flow of FIG.

  In this way, the reception confirmation is performed so that the reception confirmation result or the “no broadcast” information in the adjacent channel presence / absence determination is stored for all the channels. If there is no adjacent channel, the reception confirmation of the corresponding channel is skipped.

  In the first embodiment, the normal reception and the reception at the time of channel scanning are premised on the same receiving circuit. However, as shown in FIG. 6, the broadcast receiving unit 12 includes the normal receiving broadcast receiving unit 18 and Alternatively, a broadcast receiving unit 19 dedicated to channel scanning may be prepared. In this case, it is possible to prepare a band pass filter (BPF) having optimum characteristics for each use of the normal reception broadcast receiving unit 18 and the channel scan dedicated broadcast receiving unit 19.

Further, when the pass band of the RF side band pass filter (BPF) 20 is widened so as to include further beyond the adjacent channel, the presence / absence of a channel is confirmed in a wide range, and it is determined that a channel other than the center channel exists. May be a scan-dedicated circuit in which the center channel is changed within the range to check whether or not reception is possible, and when it is determined that there is no channel other than the center channel, the scan is collectively skipped.
FIG. 7 is a flowchart of an example (Example 3) in that case.

  When scanning from the a channel to the b channel, in FIG. 7, first, for example, a band obtained by adding 1/2 of a certain bandwidth to the a channel is set as the center channel (step S21), and the reception of the center channel is confirmed (step S21). S22) The presence / absence of reception (reception availability) is stored in the scan result holding unit 17 (step S23).

  Next, the presence / absence of an adjacent channel is determined (step S24). If there is an adjacent channel, a band obtained by adding a certain bandwidth to the current center channel is set as a new center channel (step S25). On the other hand, when there is no adjacent channel, after storing no broadcast other than the central channel within the bandwidth (step S26), a new central channel is set (step S25). This is repeated until the central channel becomes b channel in step S27.

  Next, channel a is set as the central channel (step S28), and whether or not reception has been stored for the central channel is confirmed (step 29). If stored, 1 is added to the central channel. A new center channel is set (step S33).

  On the other hand, if not stored, the reception of the central channel is confirmed (step S30), and the presence / absence of reception (reception availability) is stored (step S31). Subsequently, the presence / absence of an adjacent channel is determined (step S32). If there is an adjacent channel, the process directly proceeds to step S33. If there is no adjacent channel, no broadcast is stored in addition to the central channel within the bandwidth ( Step S34), go to step S33. This is repeated until the central channel becomes b channel in step S35.

Alternatively, if the pass band width of the RF side band pass filter (BPF) 20 is variable, the presence / absence of a channel is confirmed in a wide range, and reception is confirmed within that range, the pass band width is narrowed. Also good.
FIG. 8 is a flowchart of an example (Example 4) in that case.

  In the case of scanning from the a channel to the b channel, in FIG. 8, first, the pass bandwidth of the RF side band pass filter (BPF) 20 is set to the initial bandwidth (step S41). Is set as the central channel (step S42). If there is a broadcast confirmed channel within the bandwidth, 1 is added to the central channel to make a new central channel (step S43), reception of the central channel is confirmed, and reception (presence / absence of reception) is confirmed. Is stored (step S44).

  Next, the presence / absence of an adjacent channel is determined (step S45). If there is an adjacent channel, it is determined whether there is information on the presence / absence of broadcasting for all channels (step S46). After storing no broadcast other than the central channel (step S47), the process proceeds to step S46. Subsequently, a band obtained by adding a certain bandwidth to the center channel is set as a new center channel (step S48), and this is repeated until the center channel becomes b channel in step S49.

  When channel b is reached, the bandwidth is reduced (step S50), and the process is repeated until the bandwidth is less than 3, for example (step S51). Here, as a method of “decreasing the bandwidth”, “bandwidth−2 (in the case of upper and lower target bandwidth)”, “bandwidth / 2”, and the like are conceivable.

  When the bandwidth is less than 3, the bandwidth is fixed to 3 (step S52), channel a is set as the center channel (step S53), and if there is reception information about the center channel, 1 is added to the center channel. Is repeated to make a new center channel (step S54).

  Next, reception of the central channel is confirmed and the presence / absence of reception (reception availability) is saved (step S55). Subsequently, the presence / absence of an adjacent channel is determined (step S56). It is determined whether there is broadcast information (step S57). If there is no adjacent channel, no broadcast other than the central channel in the bandwidth is stored (step S58), and the process proceeds to step S57. Repeat until all channels are finished.

  In the above embodiment, as a method for determining the presence / absence of an adjacent channel, the method using the control amount of RF-AMP and IF-AMP is shown as an example. Other methods are also acceptable. For example, the control amount of the amplifier circuit may be passed to the control unit as the reception status, and the control unit may determine whether there is an adjacent channel.

  If there is a function that improves the reception characteristics by reducing the influence of adjacent channels without preparing special adjacent channel determination means, the function determines the presence of adjacent channels and uses the result. It is also possible to do. For example, in Japanese Patent Application Laid-Open No. 2003-318761, a method for improving the adjacent disturbance characteristic by shifting the pass band of the IF side band pass filter up and down so as to improve the bit error rate is proposed. When the passband is shifted, it may be determined that there is an adjacent channel.

  Further, the RF side band pass filter (BPF) 20 is not a filter in which the pass band is symmetrically spread to both the upper adjacent channel and the lower adjacent channel with the reception confirmation channel as the center, but the reception confirmation channel and the upper or lower side. It is also possible to use an asymmetric filter that extends to only one of the side adjacent channels. If a BPF whose passband is a part of the upper or lower adjacent channel and the reception confirmation channel is used, the determination result of the presence or absence of the adjacent channel becomes the determination result for one adjacent channel. In the case of a symmetric filter, it is not known whether there is an adjacent channel on the upper side or the lower side. However, if an asymmetric filter is used, only one of the upper side and the lower side is determined. Is possible.

  The scan flow may be a flow that skips reception confirmation of the corresponding channel when it is determined that there is no adjacent channel. For example, when performing channel scan from channel a to channel b, if two channels are skipped in the order of (a + 1) channel, (a + 4) channel,... A flow for confirming whether or not reception is finely performed for the determined portion may be used. The flow is also changed when the passband is changed.

  Furthermore, it is possible to apply not only to channel scanning but also to search channel selection in which physical channels are received and confirmed in order, and viewing is performed when a receivable channel is found.

  Although the above-described embodiment has been described assuming digital terrestrial broadcasting, it can also be applied to analog broadcasting.

It is a block diagram which shows the structure of the broadcast receiver to which Example 1 of this invention is applied. It is a block diagram which shows the structure of the broadcast receiving part. It is a figure which shows the change of the controlled variable of the amplifier circuit by the side of RF, and the amplifier circuit by the side of IF. 3 is a flowchart showing the operation of the first embodiment. It is a schematic diagram which shows the example of the reception result preserve | saved by the scanning result holding | maintenance part by it. It is a block diagram which shows the structure of the broadcast receiver to which Example 2 of this invention is applied. 10 is a flowchart illustrating the operation of the third embodiment. 10 is a flowchart illustrating the operation of the fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Broadcast receiver 11 Antenna 12 Broadcast receiving part 13 Key input part 14 Control part 15 Display part 16 Audio | voice presentation part 17 Scan result holding part 18 Normal reception broadcast receiving part 19 Channel scan dedicated broadcast receiving part 20 Band pass filter by RF side (BPF)
21 RF side amplifier circuit (RF-AMP)
22 Mixing circuit 23 IF-side bandpass filter (BPF)
24 IF side amplifier circuit (IF-AMP)
25 OFDM demodulator 26 Local oscillator 27 Automatic gain controller (AGC controller)

Claims (15)

  In a broadcast receivable channel confirmation method for receiving a reception channel received by a broadcast receiver, a reception receivability confirmation of whether or not the reception channel is receivable is performed while changing a target reception channel. A broadcast receivable channel characterized by determining whether or not there is at least one adjacent channel adjacent to the adjacent channel, and skipping the reception availability confirmation step for the adjacent channel when there is no adjacent channel. Confirmation method.   2. The broadcast receivable channel confirmation method according to claim 1, wherein the presence / absence of an adjacent channel is determined for adjacent channels on both the upper side and the lower side with respect to the reception channel for which reception is confirmed.   2. The broadcast receivable channel confirmation method according to claim 1, wherein the presence / absence of an adjacent channel is determined only for one of the adjacent channels on the upper side or the lower side with respect to the reception channel for which reception is confirmed.   4. The broadcast receivable channel confirmation method according to claim 1, wherein confirmation of reception of the reception channel and determination of the presence / absence of adjacent channels are skipped every several channels.   5. The broadcast receivable channel confirmation method according to claim 1, wherein the number of channels for judging whether or not there is an adjacent channel is increased or decreased by increasing or decreasing the pass band of the band pass filter.   6. The reception pass / fail confirmation is performed by widening the pass band of the band pass filter when determining the presence / absence of an adjacent channel, and narrowing the pass band when the determination result indicates that there is an adjacent channel. To check the broadcast receivable channels.   7. The broadcast receivable channel confirmation method according to claim 1, wherein the presence / absence of an adjacent channel is determined from a control amount of an amplifier that amplifies a received signal.   In a broadcast receivable channel confirmation device that performs reception availability confirmation on whether or not the reception channel is receivable by a broadcast receiver using a reception availability confirmation means while changing the target reception channel. When the reception channel for which reception is confirmed by the reception availability confirmation unit is provided with an adjacent channel presence / absence determination unit that determines the presence / absence of at least one adjacent channel adjacent to the reception channel, the determination result is that there is no adjacent channel. A broadcast receivable channel confirmation device, wherein the reception availability confirmation unit skips the reception availability confirmation for the adjacent channel.   9. The broadcast receiving according to claim 8, wherein the adjacent channel presence / absence determining means determines the presence / absence of an adjacent channel with respect to adjacent channels on both the upper side and the lower side of the reception channel for which reception is confirmed. Possible channel confirmation device.   9. The broadcast receivable channel confirmation device according to claim 8, wherein the adjacent channel presence / absence judging means judges only the adjacent channel on the upper side or the lower side with respect to the reception channel to be received or not. .   11. The reception availability confirmation means and the adjacent channel presence / absence judgment means perform confirmation of reception availability of the reception channel and judgment of the presence / absence of the adjacent channel by skipping every several channels. The broadcast receivable channel confirmation device as described.   A passband varying means for varying the passband of the bandpass filter is provided, and the adjacent channel presence / absence judging means varies the number of adjacent channels to be judged according to the change of the passband by the passband varying means. The broadcast receivable channel confirmation device according to any one of 8 to 11.   When determining the presence / absence of an adjacent channel, the reception availability confirmation means widens the pass band of the band pass filter by the pass band variable means, and when the determination result indicates that there is an adjacent channel, the pass band is narrowed to confirm reception availability. The broadcast receivable channel confirmation apparatus according to claim 12, wherein:   14. The broadcast receivable channel confirmation apparatus according to claim 8, wherein the adjacent channel presence / absence determining means determines the presence / absence of an adjacent channel based on a control amount of an amplifier that amplifies a received signal.   15. The adjacent channel presence / absence determining means is incorporated in a channel scanning broadcast receiving unit different from the normal receiving broadcast receiving unit that performs a normal receiving operation. Broadcasting receivable channel confirmation device.

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