JPH06268934A - Television receiver - Google Patents

Abstract

PURPOSE:To select a proper broadcast station automatically to always keep an excellent reception level even when a reception position of the television receiver is changed. CONSTITUTION:A current reception position of an on-vehicle television receiver is detected by a GPS receiver 2 and a reception area selection microcomputer 6 is used for collation by using a frequency dependent reception area storage ROM 4 storing reception areas by each frequency of a master station and a satellite station, and a tuning control circuit 7 selects automatically the frequency of a broadcast station in the reception area including its own vehicle position. Furthermore, a television radio wave received by an antenna 8 is converted into an IF signal by a tuner 9 and a reception level detection circuit 11 detects a reception level of a television radio wave based on an RFAGC signal outputted from a television linear circuit 10. Or based on the detected reception level, the reception area selection microcomputer 6 may be used for channel selection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver which always maintains a good reception level even if the receiving position of the television receiver moves.

[0002]

2. Description of the Related Art In recent years, along with the spread of automobiles, the opportunities for using cars for entertainment and the like have increased. For example, in order to spend time before reaching a destination without getting bored, audio equipment such as car stereos and in-car The number of cars equipped with TV sets for watching TV programs is increasing.

As described above, a vehicle-mounted television receiver mounted with a television receiver on a moving vehicle watches a television program while receiving television waves even while the vehicle is running.

However, it is known that, in general, television radio waves have a short wavelength and have a straight traveling property, so that a place where radio waves are hard to reach is likely to occur due to obstacles or the like. In particular, in the case of an on-vehicle TV receiver, the reception position always changes as the vehicle travels, so if the vehicle travels in the mountains or moves to a remote location away from the TV broadcasting station (parent station), There were more opportunities to enter the visually impaired area where it is difficult to receive, and it was not possible to normally watch TV broadcasts while in the impaired area.

Therefore, conventionally, in the above-mentioned blind areas,
A relay broadcasting station (hereinafter referred to as satellite station) is installed,
The same content is broadcast by frequency modulation, and it is broadcast in a frequency band different from that of the parent station. For this reason,
If you continue to watch the same TV broadcast as the parent station when the car enters the blind area, set the reception frequency of the TV receiver to the frequency of the satellite station (for example, the corresponding channel of UHF).
By switching to, it is possible to watch a TV program in an appropriate image state even in a place where the master station was in a blind area.

On the other hand, when the television receiver enters the service area of the master station away from the receivable area (service area) of the satellite station, the reception level of the master station becomes higher, so the master station side I switched to the frequency of and got a better reception condition.

[0007]

However, in such a conventional television receiver, for example, when a vehicle equipped with the television receiver travels across the service areas of the master station and the satellite station. However, there is a problem that a tuning operation for switching to any channel has to be performed every time when it comes near the boundary of each service area, which is troublesome.

[0008] Further, even when a channel selection operation is performed, even a trained person can properly select a channel because the channel selection side does not have information necessary for the channel selection. Had the problem of being difficult.

More specifically, when a car equipped with a television receiver is in the service area of the master station, the TV channel can be watched in an appropriate reception state by selecting the channel of the master station. it can. However, if you are out of the service area of the parent station while the vehicle is running, you will not be able to receive TV signals from the parent station unless you switch the receiving channel, and you may be able to continue watching TV with proper images. become unable. Therefore, U broadcasting the same contents as the parent station
When a satellite station such as HF is near, a channel selecting operation for searching for a channel of the satellite station is performed. In addition, if the car is further out of the service area of the satellite station, the viewer himself will not be able to receive the TV signal from other satellite stations or the parent station in a better receiving state as described above. It was very troublesome to redo the channel selection work. Therefore, an object of the present invention is to provide a television receiver capable of automatically selecting an appropriate broadcasting station so that a good reception level can always be maintained even if the receiving position of the television receiver changes. .

[0010]

The means of the present invention are as follows.

In order to achieve the above object, the present invention provides a television receiver for selecting and receiving television broadcast radio waves having the same content, which are emitted from a plurality of broadcasting stations at different frequencies. The receiving position detecting means for detecting the receiving position, the receiving area storing means for storing the receiving area corresponding to each frequency emitted by the plurality of broadcasting stations, and the receiving position of the television receiver detected by the receiving position detecting means And a frequency switching means for switching to a frequency corresponding to the included reception area.

According to a second aspect of the present invention, in a television receiver for selecting and receiving television broadcast radio waves of the same content emitted from a plurality of broadcasting stations at different frequencies, for each frequency emitted from the plurality of broadcasting stations. The receiving level detecting means for detecting the receiving level of the television radio wave, and the frequency switching means for switching to the frequency of the broadcasting station having the highest receiving level among the receiving levels detected by the receiving level detecting means.

The television receiver may be, for example, a vehicle-mounted television receiver mounted in a vehicle as described in claim 3.

[0014]

The operation of the means of the present invention is as follows.

According to the first aspect of the present invention, the reception position of the television receiver mounted on the vehicle is detected by the reception position detecting means, and the reception area corresponding to each frequency emitted by a plurality of broadcasting stations is detected by the reception area storage means. While being stored, the reception frequency is switched to the frequency of the broadcasting station in the reception area including the reception position of the television receiver.

Therefore, even if the receiving position of the television receiver changes, it is possible to always grasp the receiving position and to know which broadcasting station is currently in the receiving region. Therefore, the optimum broadcasting station based on the receiving region is obtained. Can be selected automatically.

According to the second aspect of the present invention, the reception level detecting means detects the reception level of the television broadcast radio waves of the same content having different frequencies, and the frequency switching means has the highest reception level among the plurality of broadcasting stations. It is switched to the frequency of the broadcasting station.

Therefore, even if the reception position of the television receiver changes, the TV radio wave with the highest reception level is selected, so that a broadcasting station with a good reception state at the current vehicle position can always be automatically selected. it can.

According to the third aspect of the present invention, since the television receiver according to the first or second aspect is an on-vehicle television receiver mounted in a vehicle, the receiving position always changes as the vehicle runs. Even if there is, it is possible to automatically select a broadcasting station with a good reception state.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIGS. 1 to 3 are views showing an embodiment of a television receiver according to the present invention. In this embodiment, the television receiver is mounted as a vehicle-mounted television receiver. is there.

First, the structure will be described.

FIG. 1 is a block diagram showing the overall construction of a vehicle-mounted television receiver according to an embodiment of the present invention.

In FIG. 1, a vehicle-mounted television receiver 1 of this embodiment uses a GPS (Glob) for positioning using a satellite as a receiving position detecting means for detecting a receiving position of the television receiver.
al Positioning System) a receiver 2, an antenna 3 for receiving positioning radio waves from satellites, and a frequency as a reception area storage unit that stores the reception area for each frequency of the master station and satellite station in association with each frequency. Separate reception area memory R
The OM (Read Only Memory) 4 and the current position of the vehicle measured by the GPS receiver 2 are stored in the reception area storage ROM 4 for each frequency.
The GPS data (vehicle position data) and the frequency-specific reception area data (service area data) are used as frequency switching means for selecting the broadcasting station in the reception area including the vehicle position by comparing with the reception area stored in the. ) And a tuning control circuit 7 for switching to the frequency of the broadcasting station corresponding to the reception area selected by the reception area selection microcomputer 6.

Further, the vehicle-mounted television receiver 1 according to the present embodiment.
Is an antenna 8 for receiving television radio waves, and a radio signal received by the antenna 8 is amplified by amplifying a reception signal in which a designated channel is selected according to a tuning signal from the tuning control circuit 7 and converted into an intermediate frequency signal (IF signal). The tuner 9 and the television linear circuit 10 are provided.

Although not shown in detail, the detailed structure of the television linear circuit 10 is composed of an intermediate frequency amplification circuit, a video detection circuit, a video amplification circuit, an AFT (automatic frequency adjustment) detection circuit, and the like.

The IF signal output from the tuner 9 of FIG. 1 is amplified by the intermediate frequency amplifier circuit of the television linear circuit 10, the video signal is detected by the video detection circuit, and the video signal is amplified by the video amplification circuit. It is transmitted as a video signal. Further, an audio signal is extracted from the output signal of the video detection circuit of the television linear circuit 10 and sent to the audio circuit 12. Further, the television linear circuit 10 takes out an S-shaped AFT signal obtained by AFT detecting the output signal of the intermediate frequency amplifier circuit by the AFT detection circuit, and outputs it to the tuning control circuit 7.

The vehicle-mounted television receiver 1 of this embodiment is also provided.
1 is an RF AGC (Radio Frequency Automatic Gain C) output from the television linear circuit 10 as shown in FIG.
The reception level detection circuit 11 detects the reception level of the television radio wave based on the ontrol signal. The reception level detection circuit 11 can feed back the detection result of the reception level to the reception area selection microcomputer 6 and use it as judgment data when selecting a reception station. For example, if the car is located at the outermost peripheral position of the satellite station's service area, it will not be possible to select an appropriate station simply by judging from the reception area.Therefore, the actual reception level between the master station and satellite station at the current position cannot be determined. Appropriate channel selection can be performed by comparison.

The audio circuit 12 is composed of an audio detection circuit and an audio amplification circuit (not shown). The audio signal output from the television linear circuit 10 is audio-detected and converted into a low frequency signal, and then audio amplification is performed. Go to speaker 13
Drive to output audio.

The video signal output from the television linear circuit 10 is sent to the sync separation circuit 14 and the chroma circuit 15.

The sync separation circuit 14 includes a horizontal sync signal (H-SYNC) and a vertical sync signal (V-) included in the video signal.
(SYNC) is input to the timing control circuit 16 separately, and the composite synchronizing signal (C-SYNC) is input to the tuning control circuit 7.

The chroma circuit 15 is for demodulating a video signal into an RGB signal.

The timing control circuit 16 creates a sampling signal (φs) based on the horizontal sync signal and the vertical sync signal sent from the sync separation circuit 14, outputs it to the A / D conversion circuit 17, and outputs the sync signal. Generate a timing signal for display based on the signal, and
8 and the segment driver 19 are controlled.

The A / D conversion circuit 17 includes the chroma circuit 1
The RGB signal output from the timing control circuit 16
Sampling is performed in synchronism with the sampling signal from, and converted into 3 to 4 bits digital data and output to the segment driver 19. The common driver 18 generates a scanning signal according to the timing signal from the timing control circuit 16 and sequentially drives the common electrodes of a liquid crystal (LC: Liquid Crystal) panel.

The segment driver 19 sequentially reads the 3- to 4-bit video data supplied from the A / D conversion circuit 17 by a timing signal from the timing control circuit, reads one line of data, and then reads the video data. In response, a gray scale signal is created to drive the segment electrodes of the LC panel 20 for display.

The key input section 21 provides the tuning control circuit 7 with key inputs such as tuning setting data and tuning up / down instructions.

Then, the tuning control circuit 7 receives the operation of the tuning up / down key in the key input section 21, the control signal input from the reception area selection microcomputer 6, the AFT signal input from the television linear circuit 10, and the like. A tuning signal is created based on this and output to the tuner 9.

Next, the operation of this embodiment will be described.

First, when watching a television broadcast from the master station with a television receiver mounted on a car, the television 8 receives the radio wave from the antenna 8 and supplies it to the tuner 9. The tuner 9 selects a designated channel according to the tuning signal from the tuning control circuit 7 and converts it into an intermediate frequency signal (IF signal). The IF signal output from the tuner 9 is transmitted to the television linear circuit 10
The video signal is detected by the video detection circuit, the video signal is output, and the audio signal is extracted from the output signal of the video detection circuit of the television linear circuit 10, and the audio signal is output. Sent to the circuit 12.

With respect to this audio signal, the audio signal from the television linear circuit 10 is audio-detected by the audio detection circuit in the audio circuit 12, converted into a low-frequency signal, and then audio-amplified by the audio amplifier circuit to be output from the speaker 13. Be uttered.

The output signal of the video detection circuit in the television linear circuit 10 is amplified by the video amplification circuit and then sent to the sync separation circuit 14 and the chroma circuit 15.
Each is processed.

Then, the sync separation circuit 14 separates the horizontal sync signal and the vertical sync signal included in the video signal and outputs them to the timing control circuit 16 and outputs the composite sync signal to the tuning control circuit 7. On the other hand, the television linear circuit 10 outputs the AFT signal to the tuning control circuit 7. In the tuning control circuit 7, an operator uses the key input unit 21 to key in data for tuning setting, a tuning up / down instruction, and the like.

In this way, the tuning control circuit 7
Then, a tuning signal is created based on a tuning up / down instruction from the key input unit 21 and an AFT signal from the television linear circuit 10 and output to the tuner 9 so that the television signal at a predetermined frequency is received. Done.

When the received television radio wave is displayed on the LC panel 20 as an image, the following operation is performed.
First, the timing control circuit 16 creates a sampling signal based on the horizontal sync signal and the vertical sync signal sent from the sync separation circuit, and outputs it to the A / D conversion circuit 17. Next, in the A / D conversion circuit 17, the RGB signal output from the chroma circuit 15 is sampled in synchronization with the sampling signal, converted into digital data of 3 to 4 bits, and output to the segment driver 19. .
Then, the timing control circuit 16 creates a timing signal for display control based on the synchronization signal given from the synchronization separation circuit 14, and controls the operation of the common driver 18 and the segment driver 19. That is, the common driver 18 generates a scanning signal according to the timing signal from the timing control circuit 16, and the LC panel 20.
The common electrodes of are sequentially driven. Further, the segment driver 19 sequentially reads the video data of 3 to 4 bits supplied from the A / D conversion circuit 17 by a timing signal from the timing control circuit 16, reads the video data of one line, and then reads the video. A gradation signal is created according to the data, and the segment electrodes of the LC panel 20 are driven to display. An image is displayed on the LC panel 20 by such an operation.

Here, when the vehicle deviates from the reception area of the master station and enters the blind area while the vehicle is running, the reception level of TV radio waves is lowered, so that noise is generated, image distortion and voice deterioration occur. It occurs, and the screen of the TV receiver becomes very difficult to see. Therefore, there has been conventionally provided a satellite station that broadcasts to a blind area by using a frequency-converted radio wave of a television broadcast having the same content as the parent station provided to eliminate the blind area.

For this reason, in this embodiment, in order to maintain a good reception level of TV radio waves even while the vehicle is traveling, the satellite reception station and the master station, which have different frequencies of the TV radio waves, have different reception areas and their own vehicle positions. It matches and automatically selects an appropriate channel.

As a concrete channel selection operation, first, a channel of a predetermined broadcasting station is selected and the image is received by the GPS antenna 3 and the GPS receiver 2 even while the image is being output to the LC panel 20. The own vehicle position data continues to be output to the reception area selection microcomputer 6, and the current position of the own vehicle is always accurately known.

Here, the reception area selection microcomputer 6 receives the information about the reception areas of the master station and the satellite stations stored in advance in the reception area storage ROM 4 for each frequency, and the GPS receiver 2 described above is input. By collating with the information of the own vehicle position from, it is possible to easily select an appropriate receiving area according to the own vehicle position. Then, the tuning control circuit 7 can automatically select a channel having a good reception level viewed from the reception area based on the selection result.

By the way, in the outermost periphery of the reception area,
The reception areas of the master station and satellite stations overlap,
Since the reception level is not stable, it may not always be possible to select an appropriate channel only in the reception area. Therefore, in the present embodiment, the reception level detection circuit 11 detects the level of the RFAGC from the television linear circuit 10 to make the reception area selection microcomputer 6
It is also possible to select a channel based on the strength of the reception level.

FIG. 2 is a flow chart showing the channel selection processing based on the reception level and the reception area, and FIG. 3 shows an example of the corresponding channels of the satellite station which frequency-converts and broadcasts a TV program having the same contents as the parent station. It is the figure shown.

As shown in FIGS. 2 and 3, for example, 3c
When the master station of h is selected to perform the reception process (step S1), first, the reception level described above is received between the master station of 3ch and the UHF satellite station of 49ch which broadcasts the same content. Are compared (step S2). If the reception level of the master station is high, the process proceeds to step S3, and if the reception level of the satellite station is high, the process proceeds to step S4.

Here, when the reception level of the master station is high,
It is judged which reception area the vehicle position belongs to (step S3), and if it is within the reception area of the master station, the process returns to step S2, and if within the reception area of the satellite station, step S4.
Proceed to.

If the reception area belongs to the satellite station in step S3 or if the reception level is higher in the satellite station in step S2, the satellite station is selected and the reception processing is performed (step S4). .

Further, during the reception processing of the satellite station in step S4, the reception levels of the satellite station and the master station are compared (step S5). Here, if the reception level of the satellite station is high, the process proceeds to step S6, and if the reception level of the master station is high, the process returns to the reception process of the master station of step S1.

Here, if the reception level of the satellite station is high, it is judged which reception area the vehicle position belongs to (step S6). If it is within the reception area of the master station, the parent station of step S1 is determined. Return to the reception processing of the station, and if it is within the reception area of the satellite station, return to the above step S5,
The reception levels are compared again.

As described above, the vehicle-mounted television receiver of this embodiment constantly compares the vehicle position with the reception area, and
Since the reception levels are repeatedly compared and the optimum broadcasting station at the current position of the television receiver is automatically selected,
The troublesome tuning operation when viewing the in-vehicle television is not necessary, and the tuning operation based on the objective information enables extremely accurate tuning.

In the above embodiment, the GPS receiving device using the satellite is used as the means for detecting the receiving position of the television receiver. However, the present invention is not limited to this, and a computer is used to detect the vehicle. It can be carried out by using a position detection system for calculating the current position from the traveling speed and the direction of the vehicle or a position detection means other than that.

Further, in the above embodiment, when selecting a channel, the judgment is made by using both the reception level and the reception area. However, only one of them may be used.

Further, in the above-described embodiment, the case where the television receiver is mounted on the vehicle has been described, but the present invention is not limited to this, and a portable television receiver is carried, or mounted on a ship, train or airplane. The same can be applied to the case of a television receiver.

As shown in FIG. 3, satellite stations broadcasting the same contents as the master station correspond to each other one-to-one, but if there are a plurality of satellite stations, they are selected. Of course, the operation is performed.

[0061]

According to the first aspect of the present invention, the reception position of the television receiver is detected, and the frequency is switched to the frequency of the reception area including the reception position of the television receiver.
Even if the reception position of the TV receiver changes as the car runs, it becomes clear from the current position of the car which broadcasting station is in the receiving area, and an appropriate broadcasting station is automatically selected based on that receiving area. As a result, a tuning operation becomes unnecessary, and a good reception state can always be maintained.

According to the second aspect of the present invention, the reception levels of a plurality of television radio waves having different frequencies and broadcasting the same contents are detected, and the frequency is switched to the highest reception level. Even if the reception position of the TV receiver changes due to the running of the car, the TV radio wave with the highest reception level is automatically selected, so the tuning operation is not required and a good reception status can be maintained at all times. .

According to the invention of claim 3, since the television receiver is a vehicle-mounted television receiver mounted in a vehicle, even if the receiving position is constantly changed by the traveling of the vehicle, the broadcasting in a good receiving state is possible. Stations can be automatically selected.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a vehicle-mounted television receiver according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a channel selection process based on a reception level and a reception area.

FIG. 3 is a diagram showing an example of corresponding channels of a satellite station that frequency-converts and broadcasts a television program having the same content as that of a parent station.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle-mounted television receiver 2 GPS receiver (reception position detection means) 3 Antenna 4 Frequency-specific reception area storage ROM (reception area storage means) 5 Frequency switching unit (frequency switching means) 6 Tuning control circuit 7 DTS microcomputer 8 Antenna 9 Tuner 10 Television linear circuit 11 Reception level detection circuit (reception level detection means)

Claims (3)

[Claims] 1. A television receiver for selecting and receiving television broadcast radio waves of the same content, which are emitted from a plurality of broadcasting stations at different frequencies, and a receiving position detecting means for detecting a receiving position of the television receiver, Reception area storage means for storing reception areas corresponding to respective frequencies emitted from a plurality of broadcasting stations, and a frequency for switching to a frequency corresponding to the reception area including the reception position of the television receiver detected by the reception position detection means. A television receiver comprising: a switching unit. 2. In a television receiver for selecting and receiving television broadcast radio waves of the same content emitted from a plurality of broadcast stations at different frequencies, a reception level of the television radio waves of each frequency emitted from the plurality of broadcast stations. A television receiver comprising: a reception level detecting means for detecting the frequency of the broadcast signal; and a frequency switching means for switching to a frequency of a broadcasting station having the highest reception level among the reception levels detected by the reception level detecting means. 3. The television receiver for selecting and receiving television broadcast radio waves of the same content emitted from the plurality of broadcasting stations at different frequencies is an on-vehicle television receiver mounted in a vehicle. The television receiver according to claim 1 or 2.