JP3321883B2 - TV receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver provided with an auto-tuning system based on, for example, a frequency synthesizer system or a voltage synthesizer system, and more particularly to a portable television receiver such as a vehicle-mounted television or a portable television.

[0002]

2. Description of the Related Art Hitherto, there has been known an automatic tuning system which automatically tunes to a broadcasting station by a frequency synthesizer system or a voltage synthesizer system. For example, a voltage synthesizer system is disclosed in US Pat. No. 4,398,303. The frequency synthesizer system is USP4,3
17, 227.

According to these techniques, the operation of an "up / down" key for instructing a tuning direction causes a broadcast station having a higher frequency or a lower frequency to be broadcast from a currently received broadcast station. It is possible to automatically search and receive, or preset the broadcast station corresponding to the channel key, such as the first broadcast station A to the channel key 1, the second broadcast station B to the channel key 3, and so on. The channel can be selected with one touch by operating a channel key.

[0004] Recently, portable liquid crystal televisions and on-vehicle televisions have become widespread. This type of television receiver is used over a wide area without fixing the use area at one place. For this reason, the radio wave condition changes drastically, and the receivable broadcast stations change with the movement of the area, and there is a problem that the above-mentioned auto tuning system cannot cope with the problem.

That is, even if a specific channel (broadcasting station) is preset in advance, if the area moves, the channel cannot be received. This is because the receivable broadcast station may fluctuate due to the influence of the above.

[0006] Some television broadcasting stations have their own service areas in cities throughout the country. It is well known that each of these television broadcasting stations configures a network system with each broadcasting station as a key station to operate television broadcasting, but even the same broadcasting station uses various channels. We broadcast. For example,
NHK General TV in Yamanashi Prefecture, Kofu 1 channel, Kofu south 31 channel, Kofu north 47 channel, Sasako 59
Channel, Otsuki 60 channel, Yamanakako 54 channel, and so on.

Therefore, in a television receiver which is assumed to be used for mobile use, when a user travels or travels to an unknown area and the reception status of a channel which has been received is deteriorated with the movement. In addition, there is a problem that it takes a lot of trouble and time to find a receivable channel which broadcasts a similar program.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and has as its object to provide a television receiver such as a liquid crystal television set which can be moved and carried by a simple operation for a desired program. An object of the present invention is to provide a television receiver capable of continuing viewing.

[0009]

That is, the present invention provides a telecommunications system.
Instruct search for receivable channels when receiving radio waves
Instruction means for receiving and receiving from the television wave by the instruction means.
Search for available channels by auto tuning
Search means and the receivable channels obtained by this search means.
The received program at the time pointed by the instruction means from the channel
Viewer selects channel broadcasting the same program as
Setting means for setting by performing
The receiving channel at the time of
Storage means for storing the received channel, and the reception intensity is detected.
And a channel stored in the storage unit.
Of the reception strength at that time
Selecting means for selecting and receiving a higher channel.
A television receiver characterized in that:

[0010]

With the above arrangement, it is possible to continue viewing a desired program with a small number of operations even in a district where the channel reception condition frequently changes.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is applied to a liquid crystal television device will be described below with reference to the drawings.

FIG. 1 shows the circuit configuration. A television wave received by an antenna 11 is sent to a tuner 12. The tuner 12 selects a TV radio wave of a specified channel in accordance with a tuning signal from a tuning control circuit 18 described later, converts it into an intermediate frequency signal, and sends it to the TV linear circuit 13.

The TV linear circuit 13 is composed of an intermediate frequency amplifying circuit, a video detecting circuit, a video amplifying circuit, an AFT detecting circuit, and the like. After amplifying the intermediate frequency signal from the tuner 12, the TV linear circuit 13 is combined with the video detecting circuit. A composite video signal including an audio signal is obtained, and the composite video signal is output to an audio circuit.

The audio circuit 14 comprises an audio detection circuit and an audio amplification circuit.
The low-frequency audio signal is obtained by performing audio detection on the composite video signal from the computer, and after amplifying the audio signal, the speaker 15 is driven to reproduce and output the audio.

The TV linear circuit 13 amplifies the composite video signal by a video amplifier circuit,
While outputting to the sync separation circuit 17, the AFT detection circuit AFT-detects the amplified composite video signal and outputs an S-shaped automatic frequency tuning signal AFT to the tuning control circuit 18.

The synchronization separation circuit 17 separates and extracts the horizontal synchronization signal H-SYNC and the vertical synchronization signal V-SYNC in the composite video signal, and extracts these horizontal synchronization signals H-SYNC.
And the vertical synchronizing signal V-SYNC is sent to the timing control circuit 19 as it is, while the horizontal synchronizing signal HS
A composite synchronizing signal C-SYNC in which the YNC and the vertical synchronizing signal V-SYNC are superimposed is sent to the tuning control circuit 18.

The tuning control circuit 18 receives key inputs such as tuning setting data, tuning up / down instructions, auto scan instructions, and memory instructions from a key input section 20. The tuning control circuit 18
A tuning signal is created based on the key operation of the tuning up / down key or the auto scan key in the key input unit 20 and the automatic frequency tuning signal AFT from the TV linear circuit 13 and output to the tuner 12, while the key input unit Corresponding to the operation of the auto scan key or the memory key in 20, the channel number being received at that time is stored in the memory circuit 21.

The timing control circuit 19 generates a sampling clock φs based on the horizontal synchronizing signal H-SYNC and the vertical synchronizing signal V-SYNC sent from the synchronization separating circuit 17 and supplies the sampling clock φs to the A / D converter 22. In addition, it sends various timing signals to the tuning control circuit 18, common driver 23, and segment driver 24.

The chroma circuit 16 performs chroma signal processing on the composite video signal from the TV linear circuit 13 to obtain R, G, B color signals, and converts the color signals to A / D signals.
Transmit to converter 22.

The A / D converter 22 sequentially samples the R, G, B color signals from the chroma circuit 16 in synchronization with the sampling clock φs from the timing control circuit 19, and outputs 3 to 4 bits per dot. The image data is converted into digital-value image data based on the gradation, and the obtained image data is sent to the segment driver 24.

However, the segment driver 24 and the common driver 23 are for driving display of the segment electrodes and the common electrodes of the liquid crystal display panel 25 which is a display unit, respectively. The segment driver 24 controls the A / D in synchronization with the timing signal from the timing control circuit 19.
The video data supplied from the converter 22 is sequentially read, and after reading one line of video data, gradation data is created based on the video data, and the segment electrodes of the liquid crystal display panel 25 are driven for display.

At this time, the common driver 23 generates a scanning signal in synchronization with the timing signal from the timing control circuit 19, and uses the generated scanning signal to control the liquid crystal display panel 25.
Are sequentially driven for display. Next, the operation of the above embodiment will be described.

For example, as shown in FIG. 3, the area I where the "A" channel (shown as "Ach") can be received and the area where the "B" channel (shown as "Bch") can be received Consider a receiving operation of a liquid crystal television set mounted on an automobile moving in the direction of arrow F on a road R passing through an area where II and II overlap as shown in the figure. Here, the "A" channel and the "B" channel are different channels but broadcast the same program by the same broadcasting station. In particular, the "A" channel is a mountain MT
Therefore, it is difficult to receive the shadowed portion. FIG. 2 mainly shows the processing contents of the reception operation by the tuning control circuit 18 during the period from the position P1 to the position P5 on the road R.

First, it is assumed that the "A" channel is received at the position P1 on the road R (step S1). In this case, the viewer on the automatic person at the position P1 can use the key input unit 20.
"A" by operating the tuning up / down key
By selecting a channel, a tuning signal corresponding to the “A” channel is sent from the tuning control circuit 18 to the tuner 12, and the tuner 12 selects a “A” channel television wave from among the receivable channels. The intermediate frequency signal is sent to the TV linear circuit 13 at the subsequent stage. The operation of each of the following television circuits is a general operation, and a detailed description thereof will be omitted.

Thereafter, it is assumed that the vehicle advances to the position P2 on the road R, and the reception state of the "A" channel is deteriorated and the reception becomes impossible (step S2). Here, the viewer operates the auto scan key of the key input unit 20 (step S3).

The tuning control circuit 18, which has received the operation signal of the auto scan key, stores the channel number of the "A" channel received so far in the memory circuit 21 and sequentially tunes the tuning signal to the tuner 12. Then, an automatic scan operation is performed in which the receivable channels are sequentially and sequentially selected for a specific time, for example, every 3 seconds, and displayed on the liquid crystal display panel 25 (step S4).

The viewer determines whether or not there is a channel broadcasting the same program as the above-mentioned "A" channel, based on the program displayed on the liquid crystal display panel 25 during the auto scan operation (step S1). S5) When the "B" channel broadcasting the same program is selected, the memory key of the key input unit 20 is operated (step S6).

By operating the memory key, the tuning control circuit 18 stores the channel number of the "B" channel in the memory circuit 21, and stores the channel number of the "A" channel stored in the memory circuit 21 after one cycle of the auto scan. , The channel "A" is selected again and its broadcast is received (step S7).

If the reception state of the “A” channel is still bad (step S 8), the tuning control circuit 18 determines “A” by the channel number stored in the memory circuit 21.
The channel and the "B" channel are received, and their reception intensities are compared based on, for example, the signal level of the automatic frequency tuning signal AFT from the TV linear circuit 13 (step S9), and the channel having the higher reception intensity is selected. To continue the receiving operation (step S10).

Thereafter, the tuning control circuit 18 counts the timing signal from the timing control circuit 19, and uses the channel numbers stored in the memory circuit 21 at appropriate time intervals, for example, every 60 seconds. Are compared (step S9), the channel having the higher reception intensity is selected, and the reception operation is continued (step S10).

With this operation, as the position on the road R moves from P2 to P5, the channel having the higher reception strength at each position is automatically selected and received.

Although not shown in FIG. 3, a district III which can receive a "C" channel which broadcasts the same program as the "A" channel and the "B" channel is adjacent to the district I and the district II. In the case of
In the process (1), the memory key of the key input unit 20 is operated not only when the "B" channel is selected but also when the "C" channel is selected during the auto scan operation.
By operating the memory key, the channel number of the "C" channel is also stored in the memory circuit 21, and as a result, the channel numbers of the "A" channel, the "B" channel, and the "C" channel are stored in the memory circuit 21. It will be. Therefore, the tuning control circuit 18 compares and selects the channel having the highest reception intensity from among the “A” channel, the “B” channel, and the “C” channel according to the contents stored in the memory circuit 21 and receives the channel. .

[0033]

As described above, according to the present invention, it is possible to provide a television receiver capable of continuing to watch a desired program with a small number of operations even in an area where channel reception conditions frequently change. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration according to an embodiment of the present invention.

FIG. 2 is a flowchart showing processing contents according to the embodiment.

FIG. 3 is an exemplary view for explaining the operation according to the embodiment.

[Explanation of symbols]

11 ... antenna, 12 ... tuner, 13 ... TV linear circuit, 14
... Sound circuit, 15 ... Speaker, 16 ... Chroma circuit, 17 ... Sync separation circuit, 18 ... Tuning control circuit, 19 ... Timing control circuit, 20 ... Key input unit, 21 ... Memory circuit, 22 ... A /
D converter, 23 common driver, 24 segment driver, 25 liquid crystal display panel.

Claims (1)

(57) [Claims] 1. An instructing means for instructing a search for a receivable channel when receiving a television wave, a searching means for automatically tuning a receivable channel from a television wave by the instructing means, and a search means obtained by the searching means. The viewer selects a channel that broadcasts the same program as the received program at the time pointed by the instruction means from among the receivable channels .
Setting means for setting Ri, receiving channel and above at the indicated time points by the instructing means
Storage means for storing the channel set by the setting means ; detection means for detecting the reception strength; and selecting the channel having the highest reception strength at that time by the detection means from the channels stored in the storage means. A television receiver, comprising: selecting means for receiving the received signal.