JPH0787415A - Method for automatically setting reception channel of receiver - Google Patents

Abstract

PURPOSE:To automate the reception mode setting operation of a receiver by allowing the receiver to search part of reception channels automatically and to judge whether the broadcast is a ground wave television broadcast or a CATV broadcast based on the result, searching remaining channels according to a channel plan and setting the storage. CONSTITUTION:A CPU 5 detects a channel having a receptible signal strength and judges whether or not the detected channel is included in a frequency band allocated for a CATV only, judges that a CATV cable 3 is connected to the receiver and a signal by a CATV broadcast is sent when plural channels are in existence, searches the channel according to a channel plan allocating the CATV and stores the result. On the other hand, when the channel is one channel or below, the reception mode is set to the ground wave television reception mode and the channel is searched according to the allocation channel plan of the ground wave television broadcast and stored.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiving channel automatic setting method for a receiver for searching, storing and setting channels for terrestrial television broadcasting and wired CATV broadcasting according to respective channel plans.

[0002]

2. Description of the Related Art Conventionally, terrestrial television broadcasting and CAT
The channel plan for V broadcasting is different from that for V broadcasting (since it is a space for terrestrial broadcasting and a dedicated cable for CATV broadcasting), the channels of the same frequency band are assigned redundantly. There was a case. Further, in CATV broadcasting, a very large number of channels are assigned to frequency bands not used in terrestrial broadcasting.

FIG. 4 is a block diagram showing a receiving channel setting method of a conventional receiver. In the figure, 1 is a TV antenna for receiving terrestrial TV broadcast waves,
2 is a distributor, 3 is a CATV cable connection terminal, and 4 is an input terminal of a receiver. Reference numeral 7 is a signal processing unit for performing frequency conversion on the received signal, 8 is a channel selection unit for selecting a signal of a desired channel frequency from the received signal, 10
Is an intermediate frequency amplifier for amplifying the signal converted into the intermediate frequency band in the signal processor 7.

[0004] 11 is a terrestrial television broadcast or CAT
A slide switch for setting the receiving mode of the receiver itself to one of V broadcasts. When setting to the receiving mode of terrestrial television broadcasting, move the slide knob to the upper side and set to the CATV receiving mode. In case, move it to the lower side. Thus, according to the conventional receiving channel setting method of the receiver, when the channel of the terrestrial television broadcast is set, the user of the receiver operates the switch 11 in advance to set the receiving mode of the receiver to the terrestrial television. Set to the broadcast reception mode. As a result, the channel selection unit 8 of the receiver or the like searches for a channel and stores and sets it according to the channel plan of the terrestrial television broadcast stored in advance. Further, when trying to receive a CATV broadcast, the switch 11 is operated to set the reception mode of the receiver to the reception mode of the CATV broadcast, and the channel is searched and stored and set according to the channel plan of the CATV broadcast stored in advance.

[0005]

Since the conventional method for automatically setting the receiving channel of the receiver is configured as described above, when the user tries to automatically set the receiving channel of the receiver, the terrestrial television is set in advance. Broadcast or CAT
It was necessary to select and set V broadcasting. Therefore, there is a problem that the operation is not easy for a user who is unfamiliar with the operation of the receiver.

The present invention has been made to solve such a problem, and a receiver automatically searches a part of receiving channels, and judges whether it is terrestrial television broadcasting or CATV broadcasting based on the result. However, it is an object of the present invention to provide a receiving channel automatic setting method for a receiver that searches for and stores the remaining channels according to the channel plan.

[0007]

According to the method for automatically setting a receiving channel of a receiver according to the present invention, a channel having a receivable signal strength is detected, and the detected channel is CAT.
If it is included in the frequency band assigned only to V, and if a plurality of channels are included, the receiving mode of the receiver is set to CATV receiving mode and CAT is set.
While searching and storing the channel according to the V allocation channel plan, when the number of channels that can be detected in the frequency band assigned only to CATV is 1 channel or less, the reception mode of the receiver is set to the terrestrial television reception mode. A channel is searched for and set according to a channel plan for wave television broadcasting.

[0008]

In the method for automatically setting the receiving channel of the receiver according to the present invention, the frequency band used in the terrestrial television broadcasting and the frequency band used in the CATV broadcasting overlap with each other. However, it is judged whether there are a plurality of receivable channels having a sufficient signal strength in a frequency band which is not used in the terrestrial television broadcasting. It is judged that the CATV cable is connected to the CATV and the signal is transmitted by the CATV broadcast, the reception mode is set to the reception mode of the CATV broadcast, and the channel search is performed based on the CATV broadcast channel plan stored in advance. The channel is set and stored by. Further, when the number of receivable channels having a sufficient signal strength in the above frequency band can be detected only less than one channel, the receiver is provided with the CATV.
Cable is not connected, and it is determined that the TV antenna for receiving terrestrial TV broadcasting is connected, and a channel search is performed based on the terrestrial TV broadcasting channel plan that is stored in advance. Remember the settings.

Since the frequency band allocated only to CATV is redundantly allocated to other purpose frequency bands such as mobile communication, there is a possibility that those signals may be received. However, since the possibility is not so great, a highly reliable judgment can be made by checking whether or not a plurality of channels, that is, at least two channels can be stably received.

[0010]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a receiving channel automatic setting method of a receiver in this embodiment. In the figure, 1 is a television antenna for receiving terrestrial television broadcasting, 2 is a distributor, 3 is a CATV cable connection terminal, 4
Is the input terminal of the receiver. Reference numeral 7 is a signal processing unit for performing frequency conversion on the received signal, 8 is a channel selection unit for selecting a signal of a desired channel frequency from the received signal,
Reference numeral 9 is a switching circuit for switching the reception mode of the receiver to either the reception mode of terrestrial television broadcasting or the reception mode of CATV broadcasting, and 10 is an intermediate frequency for amplifying the signal converted into the intermediate frequency band in the signal processing unit 7. It is an amplifier.

Reference numeral 6 is a level detector for detecting the output level of the intermediate frequency amplification unit 10, and 12 is an RO which stores channel plans for terrestrial television broadcasting and CATV broadcasting.
M and 13 are RAMs for storing the result of tuning, and 5 is a CPU
The channel selector 8 and the switching circuit 9 are controlled based on the information in the level detector 6 and the ROM 12.

Next, the operation of the hardware will be described. For convenience of explanation, it is assumed that a CATV dedicated cable is connected to the input terminal 4. First, the CPU 5 controls the channel selection unit 8 and the switching circuit 9 according to the program and the channel plan stored in the ROM 12 in advance. This output is given to the signal processing unit 7, and the signal processing unit 7 determines the reception frequency. Here, the CATV signal input to the input terminal 4 of the receiver is selectively received by the signal processing unit 7, further amplified by the intermediate frequency amplifying unit 10, and guided to the video circuit of the television receiver thereafter. Further, a part of the output of the intermediate frequency amplifier 10 is branched and sent to the level detector 6 to detect its level and A / D convert it, and then the CPU
It is fed back to 5. That is, the received signal strength information of the CATV signal selectively received by the signal processing unit 7 is finally returned to the CPU 5.

Next operation will be described. FIG. 2 is a flow chart for explaining the operation. FIG. 3 is a channel assignment table for terrestrial television / CATV in the United States. According to this assignment table, the frequencies are assigned to the CATV channel plan over almost the entire frequency band. On the other hand, in the terrestrial television broadcasting channel plan, the number of channels is small because there are breaks in the middle.

First, channels 1 to 13 are selected (step S1). Here, the tuning is the CPU 5
Controls the switching circuit 9 and the channel selection unit 8 for each channel to determine the reception frequency, the signal processing unit 7 selectively receives the signal based on the information, and the intermediate frequency amplification unit 10 amplifies the received signal. The level detector 6 detects the signal strength, and when the signal strength is above a certain level at which the signal strength can be received, the CPU 5 judges that there is a broadcast signal, and R
The operation of storing the existence of the channel in the AM 13. Channels 2 to 13 have the same frequency allocation for terrestrial television broadcasting and CATV broadcasting.

Channel 14 of CATV is selected (step S2). Variable CH that records the number of CATV stations
0 is substituted for and initialized (step S3). As a result of selecting channel 14 of CATV, if there is a receivable channel, the process branches to YES; otherwise, the process branches to NO (step S
4). In the case of YES, the value of the variable CH is incremented by 1 (step S5). Next, channel 14 of terrestrial broadcasting is selected (step S6). At this stage, it is unclear whether the terrestrial broadcasting service or the CATV service is being received, so both channels are selected.

Channel 15 of CATV is selected (step S7). As a result of selecting channel 15 of CATV, YES if there is a receivable channel, N if not
It branches to O (step S8). In the case of YES, the value of the variable CH is incremented by 1 (step S9). After that, if the value of the variable CH is judged to be 2 (step S10), the process proceeds to YES, and it is judged to be the CATV mode because there are two or more receivable channels in the CATV channel. Is selected (step S12). If step S8 is NO, channel 15 of terrestrial broadcasting is selected (step S11). Similarly, at this stage, since it is unclear whether the terrestrial broadcasting service or the CATV service is being received, both channels are selected.

After step S13, the designated channel is set to 1
Repeat up to channel 35, increasing in increments. When the value of the variable CH becomes 2 on the way, it is judged to be the CATV mode, and thereafter, only the CATV channel is selected up to 125 channels (step S13 to step S2).
9).

If NO in step S26, it is determined that there is no receivable channel of two or more channels in the CATV frequency band, and the terrestrial broadcasting mode is determined. After that, only the terrestrial broadcasting channel is up to channel 69. Channel selection (step S30).

Although the channel selection work is completed as described above, when the terrestrial broadcasting mode is finally determined, the information stored as the CATV channel is cleared. The reverse is also true.

[0020]

As described above, according to the present invention, a channel having a receivable signal strength is detected, and it is determined whether or not the detected channel is included in the frequency band assigned only to CATV. When a plurality of channels are included, the receiving mode of the receiver is set to the CATV receiving mode, and the channels are searched and stored according to the CATV assigned channel plan, while the CATV is set.
If the number of channels that can be detected in the frequency band assigned to only one is less than one channel, set the receiving mode of the receiver to the terrestrial television reception mode and search for and store the channel according to the terrestrial television broadcasting assigned channel plan. Since it is configured as described above, there is an effect that the receiving mode setting operation by the user of the receiver becomes unnecessary.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a reception channel automatic setting method of a receiver according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an operation of a receiving channel automatic setting method of a receiver according to an exemplary embodiment of the present invention.

[Fig. 3] Allocation frequency and C of terrestrial television broadcasting in the United States
It is a list of assigned frequencies of ATV broadcasting.

FIG. 4 is a block diagram showing a configuration of a receiving channel automatic setting method of a conventional receiver.

[Explanation of symbols]

 1 TV Antenna 2 Distributor 3 CATV Cable Connection Terminal 4 Input Terminal 5 CPU 6 Level Detector 7 Signal Processor 8 Channel Selector 9 Switching Circuit 10 Intermediate Frequency Amplifier 11 Slide Switch 12 ROM 13 RAM

Claims (1)

[Claims] 1. A channel having a receivable signal strength is detected, whether or not the detected channel is included in a frequency band assigned only to CATV, and when a plurality of channels are included, reception is performed. The receiving mode of the device is set to the CATV receiving mode, the channels are searched and stored according to the CATV assigned channel plan, while the number of channels that can be detected in the frequency band assigned only to CATV is 1 channel or less,
A method for automatically setting the receiving channel of the receiver that sets the receiving mode of the receiver to the terrestrial television receiving mode, searches for channels according to the terrestrial television broadcasting assigned channel plan, and sets them.