JP2000031850A - Fm multiplex broadcasting receiver, control method therefor and navigation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save power for FM multiplex broadcasting receiver capable of receiving character information and VICS information. SOLUTION: Concerning FM multiplex broadcasting receiver 10, just while the character information or VICS information is received, a duty control circuit 38 switches the duty ratio of power supplied from a power source 3 to 50%. When the character information or the like is completely received and all the information is plotted by a plotter 28, a plotting complete signal ϕ1 is outputted from the plotter 28 to the duty control circuit 38. When the plotting complete signal ϕ1 is detected, the duty control circuit 38 switches the duty ratio of power supplied from the power source 3 to 100%. Thus, by regulating power to be supplied to a back light 36, power consumption of the back light 36 can be reduced so that power for the FM multiplex broadcasting receiver can be saved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FM multiplex broadcast receiving apparatus capable of receiving display information (character information, VICS information) and displaying the information, and a control method thereof.

[0002]

2. Description of the Related Art In FM multiplex broadcasting, a text information providing service known by a name such as "visible radio" or "Aladdin" and a VICS service for providing road traffic information such as traffic jams are provided. Character information (display information) and VICS information (display information) provided by these services are
It can be received and displayed by the M multiplex broadcast receiving device.
When receiving the FM multiplex broadcast, the FM multiplex broadcast receiving apparatus extracts display information transmitted in the multiplex broadcast and displays the information on the display device. In the FM multiplex broadcast receiving apparatus, first, before acquiring all of the display information, table of contents information included in the display information is acquired,
The information is displayed on a display device. From the displayed table of contents, predetermined items such as traffic jam information, news, sports,
When a user selects a predetermined item from items such as a weather forecast, reception of detailed display information corresponding to the item is started. Thereafter, when the reception of this information is completed, the detailed information, for example, VICS information such as character information such as news and map information is displayed on the display device. While the detailed display information is being received, a comment such as "Now receiving" is often displayed.

[0003]

Here, most of the power consumed in the FM multiplex broadcast receiving apparatus is consumed in the display apparatus. In particular, in a portable FM multiplex broadcast receiving device, the power consumption of the display device may occupy ２〜 to ／ of the power consumption of the entire device. For this reason, if the power consumed by the display device can be reduced, power saving can be achieved for the entire device.

SUMMARY OF THE INVENTION [0004] In view of the above, an object of the present invention is to provide an FM having a configuration capable of reducing power consumed by a display device.
A multiplex broadcast receiving apparatus and a control method thereof are provided.

Another object of the present invention is to provide a navigation system having the new FM multiplex broadcast receiving device.

[0006]

Here, it takes a certain time to finish receiving all the detailed display information corresponding to the item selected from the table of contents. In particular, simple graphics and map information provided as level 2 and level 3 in the VICS service are image data, and therefore have a much larger data amount than character information. It takes about 2 to 3 minutes to complete the reception of such information.
It is necessary to wait to some extent until the CS information is displayed.
In addition, even if it is text information, if the information corresponding to the selected item, for example, news information extends to several pages, by the time the text information is completely received,
As with VICS information, it takes a certain amount of time. For this reason, even after receiving the information of one page and displaying this page on the display device, it is necessary to wait several minutes before the page can be turned smoothly. further,
In an area where the radio wave condition of FM broadcasting is poor, it may take more time to capture data.

In the present invention, attention is paid to such a point, and when it is necessary to wait until display information is displayed, such as during reception of display information, the power supplied to the display device is reduced. Alternatively, power consumption of the display device is reduced by stopping power supply to the display device.

[0008] That is, an FM multiplex broadcast receiving apparatus of the present invention comprises an FM multiplex broadcast receiving means capable of receiving the FM multiplex broadcast and a display means capable of displaying display information contained in the FM multiplex broadcast. In the apparatus, a supply power adjusting means for adjusting the power to be supplied to the display means based on the reception status of the display information is provided.

On the other hand, a control method of an FM multiplex broadcast receiving apparatus according to the present invention is a control method of an FM multiplex broadcast receiving apparatus for receiving an FM multiplex broadcast and displaying display information included in the FM multiplex broadcast on a display means. A supply power adjustment step is provided for adjusting the power supplied to the display means based on the reception status of the display information.

In the FM multiplex broadcast receiving apparatus or the control method according to the present invention, the power supplied to the display means can be adjusted based on the reception status of the display information in the supply power adjusting means or the supply power adjusting step. For example, during a period during which display information is being received, or when display information cannot be obtained in a place where radio waves are difficult to reach, the power supplied to the display means can be reduced or the power supply can be stopped. Therefore, the power consumed by the display means can be reduced. As described above, since the power consumption of the display unit that consumes the most power in the FM multiplex broadcast receiving apparatus can be reduced, the power consumption of the entire apparatus can be reduced. As a result, the portable FM
In the multiplex broadcast receiving apparatus, the battery life can be extended.

Here, the display information is updated to the latest information at a 5-minute pitch. For this reason, old display information may continue to be displayed forever without the display information being updated due to a bad reception condition of the display information. Such display information can be determined to be obsolete, and displaying it on the display means does not make much sense. For this reason,
In such a case, it can be considered that power is wasted on the display means. Therefore, in the present invention,
When the display information has not been updated for a certain period of time, it is desirable to reduce the power supplied to the display means or stop the power supply.

As described above, among the display information, VIC
Since the S information may include image data having a very large data amount such as a simple figure or map information, VICS
It is effective to reduce the power supplied to the display means or stop the power supply based on the information reception status.

When a display means having a display panel and a backlight is employed as the display means, the power supplied to the backlight may be adjusted. With this power adjustment, the brightness of the backlight can be increased or decreased, and the display panel can be darkened or brightened.

The FM multiplex broadcast receiving apparatus of the present invention
By using a navigation unit capable of supplying a navigation image to the display means of the M multiplex broadcast receiving apparatus, it is possible to construct an automobile or portable navigation system.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an example of a navigation system including an FM multiplex broadcast receiving device. A navigation system 1 shown in FIG. 1 is an automobile navigation system, and includes an FM multiplex broadcast receiving apparatus 10 to which the present invention is applied and a navigation unit 2.
The system 1 is supplied with power from a power supply (battery) 3 mounted on a car. The FM multiplex broadcast receiving device 10 includes an FM multiplex tuner unit 11 capable of receiving the FM multiplex broadcast, and a display device 12 capable of displaying display information (character information and VICS information) included in the FM multiplex broadcast.
And a supply power adjusting device 13 capable of adjusting the power supplied to the display device 12. The display device 12 can also display a navigation image such as a map supplied from the navigation unit 2.

FIG. 2 is a schematic block diagram of a control system of the FM multiplex broadcast receiving apparatus. An FM broadcast antenna 5 is connected to the FM multiplex tuner unit 11. The high frequency signal of the FM broadcast received by the antenna 5 is transmitted to the FM tuner 21.
Supplied to The FM tuner 21 supports FM multiplex broadcasting, and adds multiplex data (display information) in addition to audio signals.
The band including the sub-carrier for carrying the signal can be extracted. In the FM tuner 21, a signal of a desired frequency band (broadcast band) set by the tuning circuit 22 is selected, converted to a predetermined baseband, and output.

The signal extracted by the FM tuner 21 is supplied to a multiplexed signal extracting filter circuit 24. If there is display information transmitted by overlapping with the subcarrier by the filter circuit 24, the information is extracted.
Then, the extracted display information is demodulated by the data demodulator 25. In FM multiplex broadcasting, LMSK is suitable for narrowing the band and has little effect on audio signals.
(Level controlled minimum shift keying) modulation method is adopted.
The K-modulated signal is demodulated to the original data. Normal F
At this stage, the character information, which is the display information transmitted by the M multiplex broadcasting, can be displayed on the display device 12 via the drawing unit 28. In contrast, the display information VI
Since the CS information is scrambled, the FM multiplex tuner unit 11 prepares a VICS descrambler 26 to decode the VICS information. The decoded VICS information is converted into image data by the drawing device 28, transmitted to the display device 12 via the interface 29, and displayed on the monitor screen of the display device 12.

The VICS information decoded by the descrambler 26 is also supplied to the navigation unit 2. For this reason, the navigation unit 2 can take in the map information and the like sent as the VICS information as the information on the navigation, and can add dynamic traffic information such as traffic congestion information to the conventional static navigation map information. The information (navigation image) of the navigation unit 2 can be displayed on the display device 12.

The drawing unit 28 is provided with a drawing memory (not shown) so that display information (VICS information or character information) sent by FM multiplex broadcasting can be temporarily stored. In this example, when the reception of the table of contents data included in the display information is completed, the table of contents corresponding to the data is displayed on the display device 12 via the drawing unit 28. Thereafter, when a predetermined item is selected by the user from the displayed table of contents, reception of detailed data corresponding to the item is started and stored. When the drawing of the data is completed by the drawing unit 28 after the reception of the detailed data is completed, the drawn data is transmitted to the display device 12 via the interface 29.
Send to and display.

The FM multiplex tuner unit 11 detects an electric field intensity of a high-frequency signal band (broadcast band) selected by the FM tuner 21 to identify a reception intensity, and a multiplex signal extracting filter circuit 24. A multiplex detection unit 32 that can determine the presence or absence of character information or VICS information from the detection result of
VIC depending on whether or not
VICS information detection unit 2 that can determine the presence or absence of S information
3 is provided. The electric field detection unit 31 includes the tuning circuit 2
2 is used to select the next broadcast band when automatic tuning is performed. For example, based on the detection result of the electric field intensity of the electric field detection unit 31, only the broadcast band (frequency band) in which the FM broadcast is provided can be selected by the tuning circuit 22. The determination results of the multiplex detection unit 32 and the VICS information detection unit 23 are transmitted to the channel selection circuit 22, and the channel selection circuit 22
It is possible to select only a broadcasting band in which character information is provided or a broadcasting band in which VICS information is provided from the determination result of. For example, it is possible to sequentially select only a broadcast band to which text information is provided, or to sequentially select only a broadcast band to which VICS information is provided.

The display device 12 includes a liquid crystal display panel 35,
A backlight 36 is provided on the back of the panel 35. Power is supplied to the backlight 36 from the power supply 3 via the supply power adjusting device 13.

The power supply adjusting device 13 includes a duty control circuit 38 capable of switching the duty ratio of the power supplied from the power supply 3, and a voltage-type inverter for supplying the power controlled by the circuit 38 to the backlight 26. A backlight drive circuit 37 is provided. The duty control circuit 38 sets the duty ratio of the reference power for display to 100%.
Has a function of switching the duty ratio of the power supplied from the power supply 3 to 100% or 50%. The duty ratio is changed by 50%.
%, And should be determined by the degree to which the liquid crystal display panel 35 is darkened.

Here, the drawing unit 28 is provided with character information and VIC.
When the drawing of the S information is completed, a drawing completion signal φ1 is output to the duty control circuit 38. For example,
After selecting a predetermined item from the table of contents of the display information displayed on the display device 12 and drawing all the detailed data of the display information, the drawing completion signal φ1 is changed to the duty control circuit 38.
Output to When identifying the drawing completion signal φ1, the duty control circuit 38 sets the duty ratio of the power to 50.
% To 100%, text information and VICS
When the reception of information starts, the duty ratio of power becomes 100
Switch from% to 50%.

FIG. 3 is an example of a flowchart of a process for switching the brightness of the screen of the display device in the FM multiplex broadcast receiving device. The FM multiplex broadcast receiving apparatus 10 starts receiving the text information or the VICS information when the broadcast band to which the text information or the VICS information is provided is selected by the tuning circuit 22 in step ST1. When reception starts, first, the table of contents data included in the information is received, and the table of contents data is displayed on the liquid crystal display panel 35 of the display device 12 via the drawing unit 28 in step ST2. In the processing so far, the backlight 36 is supplied with power having a duty ratio of 100% from the supply power control device 13.

Next, in step ST3, when a predetermined item is selected from the displayed table of contents by the user, in step ST4, the duty control circuit 38 is selected.
50% duty ratio of power supplied from power supply 3
And supplies this power to the backlight 36 via the backlight drive circuit 37. As a result, the brightness of the backlight 36 decreases and the liquid crystal display panel 35 becomes dark. Further, since the power supplied to the backlight 36 decreases, the power consumed by the backlight 36 decreases.

When a predetermined item is selected from the table of contents, reception of detailed character information or VICS information corresponding to the item is started, and the detailed information data is stored in step ST5. Next, in step ST6, when all the detailed character information or VICS information has been drawn, the drawing unit 28
Output the drawing completion signal φ1 to the duty control circuit 38. When the duty control circuit 38 detects the drawing completion signal φ1 in step ST7, the duty ratio of the power supplied from the power supply 3 is switched to 100%, and this power is transmitted to the backlight 36 via the backlight driving circuit 37.
To supply. As a result, the brightness of the backlight 36 increases, and the liquid crystal display panel 35 becomes bright.

When the drawing of detailed character information or VICS information is completed, the drawing unit 28
9 and outputs the drawn information to the liquid crystal display panel 35. Thus, the character information or the VICS information is displayed on the liquid crystal display panel 35. For example, V information such as text information such as news and sports, simple figures or map information, etc.
The ICS information is displayed. After that, when another item is selected from the table of contents, the processing after step ST4 is repeated.

As described above, in the FM multiplex broadcast receiving apparatus 10, the power supplied to the backlight 36 of the display device 12 is based on the reception status of the display information before the completion of the reception of the display information (character information or VICS information). Has been reduced. Accordingly, the power consumed by the backlight 36 can be reduced, and the power consumption of the FM multiplex broadcast receiving apparatus 10 can be reduced. Here, before the completion of the reception of the display information, it is a waiting time necessary for displaying the information of the item selected by the user, and even if the liquid crystal display panel 35 is darkened, the user does not feel uncomfortable.

Here, instead of switching the duty ratio of the power supplied from the power supply 3 to increase or decrease the power supplied to the backlight 36, the power supply to the backlight 36 may be turned on and off. FIG. 4 shows an example of an FM multiplex broadcast receiving apparatus capable of turning on and off power supply. As shown in this figure, the backlight 3 is switched by using a changeover switch 39 instead of the duty control circuit 38.
6 may be turned on and off. That is, when the drawing completion signal φ1 is identified, the changeover switch 39
Is turned on, and the switch 39 may be controlled to be turned off during the period of receiving character information and VICS information.

When the power supply to the backlight 36 is turned off, the liquid crystal display panel 35 becomes dark and there is a possibility that the device is erroneously recognized as not operating. In such a case, an LED is provided. It is desirable that the user can recognize that the character information or the VICS information is being received by lighting or blinking it.

The FM multiplex broadcast receiving apparatus 10 of the present embodiment
Is for an automobile, but the FM multiplex broadcast receiving apparatus of the present invention is also applicable to a portable FM multiplex broadcast receiving apparatus having a built-in battery. When the present invention is applied to a portable device, the life of a battery built in the device can be extended.

[Embodiment 2] Here, the character information and VICS information are updated to the latest information at intervals of about 5 minutes. For this reason, there is a possibility that old information may be displayed forever without updating the character information or VICS information due to bad reception conditions or the like. Since such information can be determined to be obsolete, continuing to display this information leads to waste of power. Therefore, in such a case, it is desirable to reduce the power supplied to the backlight 36 of the display device 12 or stop the power supply to the backlight 36.

FIG. 5 shows an example of an FM multiplex broadcast receiving apparatus having a configuration capable of reducing the power supplied to the backlight when the text information or VICS information is not updated to the latest one. The FM multiplex broadcast receiving apparatus 10A shown in FIG.
In the figure, the same reference numerals are given to parts common to the above-described FM multiplex broadcast receiving apparatus 10, and detailed description thereof will be omitted.

The FM multiplex tuner unit 11A of the FM multiplex broadcast receiving apparatus 10A includes a data update determination circuit 41 capable of determining whether or not display information, that is, text information or VICS information has been updated to the latest one. And a timer unit 42 for measuring the time. When a predetermined time is measured by the timer unit 42, the data update determination circuit 41 checks the character information or VICS information drawn on the drawing device 28 to determine whether the information has been updated. When the character information or the like is not updated, the duty control circuit 3
8, a signal φ2 indicating this is output. When the duty control circuit 38 identifies this signal φ2, the above-described FM
Similarly to the multiplex broadcast receiving apparatus 10, the duty ratio of the power supplied from the power supply 3 is switched to 50% to reduce the power supplied to the backlight 36.

FIG. 6 is an example of a flowchart of a process for switching the brightness of the screen of the display device in the FM multiplex broadcast receiving apparatus 10A. In the FM multiplex broadcast receiving apparatus 10A, first, in step ST10, as in the FM multiplex broadcast receiving apparatus 10 described above, the text information or the VICS
When a broadcast band to which information is provided is selected by the tuning circuit 22, reception of text information or VICS information is started.

Although not shown in FIG. 6, when the reception of the information is started and the reception of the index data included in a part of the information is completed, the index data is transferred to the drawing device. 28, the liquid crystal display panel 3 of the display device 12
5 is displayed. When the user selects a predetermined item from the displayed table of contents, reception of detailed character information or VICS information corresponding to the item is started.

Next, in step ST11, the detailed character information data or VICS information data is stored. Next, in step ST12, detailed character information or VICS
When all the information is drawn, the drawn information is transmitted to the liquid crystal display panel 35 via the interface 29 in step ST13, and is displayed on the panel 35.

Next, in step ST14, when a predetermined time is counted by the timer unit 42, the data update determination circuit 41 determines whether the character information or the VICS information stored in the drawing unit 28 has been updated. I do. Note that the update determination by the data update determination circuit 41
The pitch is not limited to the pitch (5 minutes) at which the character information or the like is updated, but may be any pitch at which the character information or the like can be determined to be obsolete. For example, since traffic congestion information and the like change every moment, update determination of this information is performed at a short pitch, and information such as news and sports does not change so much. Therefore, update determination of these information may be performed at a relatively long pitch. .

If it is determined in step ST14 that the character information or the like has not been updated by the data update determination circuit 41, the circuit 41 sends a signal φ2 indicating this to the duty control circuit 38. Duty control circuit 38
When the signal φ2 is identified, the duty ratio of the power supplied from the power supply 3 is switched to 50% in step ST15, and this power is supplied to the backlight 36 via the backlight drive circuit 37. As a result, the brightness of the backlight 36 decreases and the liquid crystal display panel 35 becomes dark. Further, since the power supplied to the backlight 36 decreases, power consumption in the backlight 36 is suppressed.

If the character information or the like has been updated in step ST14, the display of the information is continued.

As described above, the FM multiplex broadcast receiving apparatus 10A
When the display information such as character information is not updated for a certain period of time and the information is obsolete, the display device 12
The power supplied to the backlight 36 is reduced. That is, the power supplied to the backlight 36 is reduced based on the reception status of the display information that the display information is not updated for a certain period. As described above, in the FM multiplex broadcast receiving device 10A, similarly to the above-described FM multiplex broadcast receiving device 10, the power supplied to the backlight 36 is reduced, so that the power consumed by the backlight 36 is reduced. And power saving of the FM multiplex broadcast receiving apparatus 10A can be achieved.

As shown in FIG. 7, similarly to the FM multiplex broadcast receiving apparatus 10 described in the first embodiment, power is supplied to the backlight 36 by using a changeover switch 39 instead of the duty control circuit 38. It may be turned on and off.

[Other Embodiments] A function of reducing the power supplied to the backlight 36 or stopping the power supply during a period in which the display information is being received, and a function of displaying the display information even after a predetermined time has elapsed. It is needless to say that the FM multiplex broadcast receiving apparatus having both the function of reducing the power supplied to the backlight 36 when the is not updated or the function of stopping the power supply may be used.

The above-described method for controlling the FM multiplex broadcast receiving apparatus can be provided by software. For example, it can be provided via a mobile recording medium such as a CD-ROM, a DVD, and a floppy disk. Also,
It can be provided by recording it on a recording medium such as a ROM or an HDD of the FM multiplex broadcast receiving apparatus.

[0045]

As described above, in the FM multiplex broadcast receiving apparatus or the control method thereof according to the present invention, the power supplied to the display means is increased or decreased based on the reception status of the display information. For this reason, for example, when the display information is being received or the display information is not updated for a certain period of time,
The power supplied to the display means can be reduced or the power supply can be stopped. Therefore, the power consumed by the display means can be reduced, so that the power consumption of the entire apparatus can be reduced. As a result, the life of the battery can be extended in the portable FM multiplex broadcast receiving device.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a car navigation system constructed using an FM multiplex broadcast receiving apparatus to which the present invention has been applied.

FIG. 2 is a schematic block diagram of a control system of the FM multiplex broadcast receiving apparatus according to Embodiment 1 of the present invention.

FIG. 3 is a flowchart illustrating an example of a process of switching brightness of a display device in the FM multiplex broadcast receiving device of FIG. 2;

FIG. 4 is a schematic block diagram showing a modification of the FM multiplex broadcast receiving apparatus shown in FIG.

FIG. 5 is a schematic block diagram of an FM multiplex broadcast receiving apparatus according to Embodiment 2 of the present invention.

FIG. 6 is a flowchart illustrating an example of a process of switching brightness of a display device in the FM multiplex broadcast receiving device of FIG. 5;

FIG. 7 is a schematic block diagram showing a modified example of the FM multiplex broadcast receiving apparatus of FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Navigation system 2 Navigation unit 3 Power supply 5 Antenna 10 and 10A FM multiplex broadcast receiving device 11 and 11A FM multiplex tuner unit 12 Display device 13 Supply power control device 21 FM tuner 22 Tuning circuit 23 VICS information detection unit 24 Multiplex signal extraction Filter circuit 25 Data demodulator 26 Descrambler 31 Electric field detection unit 32 Multiplex detection unit 35 Liquid crystal display panel 36 Backlight 37 Backlight drive circuit 39 Switch

Claims (10)

[Claims] 1. An FM multiplex broadcast receiving apparatus comprising: FM multiplex broadcast receiving means capable of receiving an FM multiplex broadcast; and display means capable of displaying display information included in the FM multiplex broadcast. An FM multiplex broadcast receiving apparatus, comprising: a supply power adjusting unit capable of adjusting the power supplied to the display unit based on the above. 2. The FM multiplex broadcast receiving apparatus according to claim 1, wherein the supply power adjusting unit stops the supply of the power or reduces the power before the reception of the display information is completed. apparatus. 3. The power supply adjusting device according to claim 1, wherein the supply power adjustment unit stops supplying the power or decreases the power when the display information is not updated for a predetermined time. FM multiplex broadcast receiver. 4. The FM multiplex broadcast receiving apparatus according to claim 1, wherein the display information is VICS information. 5. The display device according to claim 1, wherein the display unit includes a display panel and a backlight, and the power supply adjusting unit controls power supplied to the backlight. An FM multiplex broadcast receiving apparatus, wherein the luminance of the backlight is increased or decreased by performing adjustment. 6. A control method of an FM multiplex broadcast receiving apparatus for receiving an FM multiplex broadcast and displaying display information included in the FM multiplex broadcast on a display means, wherein the display is performed based on a reception state of the display information. A method for controlling an FM multiplex broadcast receiving apparatus, comprising a supply power adjusting step of adjusting power supplied to a means. 7. The FM multiplex broadcast reception according to claim 6, wherein in the supply power adjustment step, the supply of the power is stopped or the power is reduced before the reception of the display information is completed. How to control the device. 8. The power supply adjusting step according to claim 6, wherein, in the supply power adjustment step, when the display information is not updated for a predetermined time, the supply of the power is stopped or the power is reduced. A control method of an FM multiplex broadcast receiving device. 9. The control method according to claim 6, wherein the display information is VICS information. 10. An FM multiplex broadcast receiving apparatus according to any one of claims 1 to 5, and a navigation unit capable of supplying a navigation image to said display means of said FM multiplex broadcast receiving apparatus. A navigation system characterized by the following.