JPH09214375A - Receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a teletext multiplex broadcast receiver to view and hear a program of audio broadcast and a program of teletext information independently. SOLUTION: The receiver is provided with a 1st reception circuit 10 receiving a teletext multiplex broadcast and a 2nd reception circuit 20 receiving a teletext multiplex broadcast, and a decoder circuit 26 extracting data of teletext information from the multiplexed signal, and a display element 28 displaying the teletext information according to an output signal from the decoder circuit 26. The signal of audio broadcast in the broadcast data received by the reception circuit 10 is fed to a headphone 17. The multiplexed signal in the broadcast received by the reception circuit 20 is fed to the decoder circuit 26, which allows the display element 28 to display the teletext information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a character multiplex broadcasting receiver.

[0002]

2. Description of the Related Art In FM broadcasting, this is called "FM text multiplex broadcasting", and it is realized that data such as text information is multiplexed and transmitted to an original audio broadcasting program.

[0003] This FM teletext broadcasting is called the DARC system, and the standard for multiplexing digital data such as text information is a subcarrier frequency: 76 kHz, a transmission rate: 16 kbit / s, a modulation method: LMSK error correction. Method: Product code using (272,190) shortened difference set cyclic code.

There are distinction between levels 1, 2, and 3 as program services such as character information. All of these are for displaying (presenting) character information etc. by dot display, but Level 1 is a service for receivers that can display 15.5 characters × 2.5 lines including the header part, Information is text. Level 2 includes the header part
This is a service for receivers that can display 15.5 characters x 8.5 lines, and information is characters and figures. In addition, level 3
Is a traffic information service for a receiver that can display a detailed map on a CD-ROM, that is, a navigation system.

As the level 1 program service, news, weather forecast, traffic information, entertainment and main complementary programs are considered. In this case, entertainment includes fortune telling, listener message boards,
It provides information such as quizzes and town information.

The main supplementary program provides supplementary information of the program such as the music title, performer name, telephone number / FAX number at the time of request when the original audio broadcast is a music program. To do.

Further, as a program service other than the above,
"Urgent information" provided at any time when there is an urgent need
Is also considered.

[Data Structure] FIG. 2 shows a frame structure of a data signal multiplexed in the FM character multiplex broadcasting. One frame of this data signal is composed of 272 blocks, and each block has 288 bits.

The 272 blocks of one frame are divided into 190 data packet blocks and 82 vertical parity packet blocks, and the vertical parity packet blocks are distributed within the frame. Sent out.

A 16-bit BIC (block identification code) is added to the beginning of each block. This BI
Four types of C are used as C, thereby distinguishing each parity packet and identifying the beginning of the frame.

The block of the data packet is BI
C is followed by a 176-bit data packet, followed by a 14-bit CRC code, followed by 82 bits.
It has a horizontal parity check code of bits.

In this case, the CRC code is added to detect the residual error after the error correction by the product code. The block of the vertical parity packet has a 272-bit vertical parity packet following the BIC.

As shown in FIG. 3, each data packet has a 32-bit prefix followed by 144 bits.
And a data block of bits. Then, the prefix has various kinds of information regarding the data block following the prefix, and the data block has information about the character actually displayed.

The above is the format in the character multiplex broadcasting by the DARC system.

[Display Example of Program] As shown in FIG. 4, a receiver corresponding to level 1 has a display device DS such as an LCD.
P is provided, and the display area SCRN has a size of 15.5 characters × 2.5 lines (horizontal 248 dots × vertical 40 dots). However, of the display area SCRN, the upper 0.5 line area is the header text display area, and the lower 2 row area is the text display area.

When the receiver receives the character multiplex broadcast, as shown in FIG. 5A, the display area SCRN of the display element DSP is displayed.
The total table of contents is displayed in. However, FIG. 5A shows a state in which the total table of contents covers a plurality of pages, and the first one of them is displayed.

When a predetermined key is operated in such a state, the next page is displayed in the display area SCRN as shown in FIG. 5B.

When the user selects and decides the number of the item to be viewed from the total contents, the contents of the selected and decided item are displayed. For example, when the user selects “3. Weather forecast” from the total table of contents, “1. Today's weather”, “2.
A table of contents such as "Tomorrow's weather" is displayed.

Further, when the user selects and determines the number of the item to be viewed from the table of contents, the first page of the selected and determined item is displayed. For example, when the user selects "1. Today's weather" from the above table of contents, specific character information about "Today's weather" is displayed as shown in FIG. 5D.

[0020]

However, when a program of audio broadcasting and a program of character information are broadcast by one radio wave in this way, it is desired to listen to the audio broadcasting program of station A.
In some cases, it may be desired to use the program of station B as the text information program.

However, in the conventional character multiplex broadcasting receivers, there is no choice but to give priority to one of the audio broadcasting program and the character information program and give up the other.

The present invention is to solve such a problem.

[0023]

Therefore, in the present invention, the character information data is multiplexed with the signal of the original audio broadcasting program, and the multiplexed signal is received. A first receiving circuit for receiving the character multiplex broadcasting, a second receiving circuit for receiving the character multiplex broadcasting, a decoder circuit for extracting the data of the character information from the multiplexed signal, and the decoder circuit A display element for displaying the above-mentioned character information according to the output signal of the above, and the signal of the audio broadcast in the broadcast received by the above-mentioned first receiving circuit is supplied to the headphones or the speaker and received by the above-mentioned second receiving circuit. The receiver is such that the multiplexed signal in broadcasting is supplied to the decoder circuit so that the character information is displayed on the display element.

As a result, the audio broadcast program and the text information program can be selected independently.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 10 indicates a first FM receiving circuit, which is an F received by an antenna 11.
The M signal is supplied to a tuner circuit 12 having an antenna input circuit to a mixer circuit and configured in a synthesizer system, and the FM signal of a target frequency is frequency-converted into an intermediate frequency signal.

Then, the intermediate frequency signal is supplied to the FM demodulation circuit 14 through the intermediate frequency circuit 13 having an intermediate frequency filter and a wide band amplifier, and the demodulated signal S14 is taken out. In this case, the demodulated signal S14 is a stereo composite signal (added signal (L) of the left and right stereo audio signals L and R when the broadcast selected by the tuner circuit 12 is a mere stereo broadcast.
+ R), the frequency-multiplexed signal of the DSB signal balanced-modulated by the difference signal (LR) and the pilot signal)
In the case of the character multiplex broadcasting, it is a frequency multiplexed signal in which the above-mentioned LMSK signal is further multiplexed with the stereo composite signal.

Then, the demodulated signal S14 is supplied to the stereo demodulation circuit 15, and the added signal (L + R) and DSB are added.
Audio signals L and R are demodulated from the signals, and these signals L and R are passed through amplifiers 16L and 16R to the left and right channel acoustic units 17 of the stereo headphones 17.
It is supplied to L and 17R.

Further, reference numeral 20 denotes a second FM receiving circuit, in which an FM signal received by the antenna 11 is supplied to a tuner circuit 22 having an antenna input circuit to a mixer circuit and configured in a synthesizer system. The FM signal of the target frequency is frequency-converted into an intermediate frequency signal.

Then, this intermediate frequency signal is supplied to the FM demodulation circuit 24 through the intermediate frequency circuit 23 having an intermediate frequency filter and a wide band amplifier, and the demodulated signal S24 is taken out. In this case, the demodulated signal S24 is, like the demodulated signal S14, a stereo composite signal when the broadcast selected by the tuner circuit 22 is a normal stereo broadcast, and a stereo composite signal when the broadcast is a character multiplex broadcast. Further, it is a frequency multiplexed signal in which the above-mentioned LMSK signal is multiplexed.

The demodulated signal S24 is supplied to one contact B of the switch circuit 25, and the demodulated signal S24 is supplied.
14 is supplied to the other contact A of the switch circuit 25, and one of the demodulated signals S14 and S24 is selected and taken out from the switch circuit 25. Then, the demodulated signal S14 or S24 thus taken out is supplied to the decoder circuit 26, the data of the character information is decoded and error-corrected from the LMSK signal and taken out, and this data is supplied to the microcomputer 27.

According to a user's instruction, the microcomputer 27 takes out character data of a program having desired character information from the data supplied thereto and converts the character data into a display signal.

Therefore, this microcomputer 27
Is connected to a system control microcomputer 30 to be described later, and data and commands related to a user's instruction are accessed. In addition, a display element, for example, an LCD 28 is connected to the microcomputer 27, and a display signal converted from character data is supplied to the display element, and the desired character information is displayed on the LCD 28.

Further, the FM receiver is provided with a microcomputer 30 for system control. The microcomputer 30 includes a CPU 31 for executing a program, a ROM 32 in which the program is written, and a work area RA.
It has an M33, an input port 34, and an output port 35. Then, these circuits 32 to 35 are connected to the CPU 31 through a system bus (not shown).

Then, tuning data is supplied from the microcomputer 30 to the tuner circuits 12 and 22, and the reception frequencies of the tuner circuits 12 and 22 are set. Further, a control signal for the switch circuit 25 is supplied from the microcomputer 30. Further, the microcomputer 30 is connected with various operation keys K1 to KN such as keys for selecting a channel and selecting character information. Further, the microcomputer 30, the decoder circuit 26 and the microcomputer 27 are connected via a data line.

In such a structure, when one of the keys K1 to KN related to channel selection is operated, the reception frequency of the tuner circuits 12 and 22 changes according to the key operation.
The frequency is controlled according to the key operation. In this way, the tuner circuits 12 and 22 select an arbitrary broadcasting station.

When the mode key KM of the keys K1 to KN is operated, the following operation is performed according to the operation of the mode key KM.

When the mode key KM is operated in the independent mode In this case, the switch circuit 25 is connected to the contact B as shown in the figure. Therefore, the demodulation signal S24 of the demodulation circuit 24
Is supplied to the decoder circuit 26 through the switch circuit 25. Therefore, if the broadcasting station selected by the tuner circuit 22 is performing character multiplex broadcasting, the decoder circuit 26 outputs character information data and the character information is displayed on the LCD 28. Is displayed in.

At this time, since the demodulation signal S14 of the demodulation circuit 14 is supplied to the stereo demodulation circuit 15, the audio broadcast program of the broadcasting station selected by the tuner circuit 12 is
It can be heard through the headphones 17.

In this case, the program of audio broadcasting and the program of character information can be independently selected by the tuner circuit 12 and the tuner circuit 22.

When the mode key KM is operated in the same mode In this case, the switch circuit 25 is connected to the contact A, which is the reverse of the drawing. Therefore, the demodulation signal S14 of the demodulation circuit 14
Is supplied to the decoder circuit 26 through the switch circuit 25. Therefore, if the broadcasting station selected by the tuner circuit 12 is performing character multiplex broadcasting, the decoder circuit 26 outputs character information data and the character information is displayed on the LCD 28. Is displayed in.

At this time, since the demodulation signal S14 of the demodulation circuit 14 is supplied to the stereo demodulation circuit 15, the audio broadcasting program of the broadcasting station selected by the tuner circuit 12 is
It can be heard through the headphones 17.

Thus, in the case of, the tuner circuit 1
According to 2, it is possible to listen to and use the audio broadcast program and the character information program of the broadcasting station selected.

When the mode key KM is operated in the automatic mode In this case, the receiving circuit 10 selects a channel, and the audio broadcast by this channel selection is heard by the headphones 17.

Further, by the microcomputer 30,
The switch circuit 25 is connected to the contact B as shown, and the reception frequency of the tuner circuit 22 is made equal to the reception frequency of the tuner circuit 12.

Then, the demodulation signal S24 of the demodulation circuit 24 is supplied to the decoder circuit 26 through the switch circuit 25,
It is determined whether the demodulated signal S24 is a stereo broadcast signal or a character multiplex broadcast signal, and the microcomputer 30 is notified of the determination result.

When the demodulated signal S24 is a character multiplex broadcast signal, character information is displayed on the LCD 28 by the decoder circuit 26 and the microcomputer 27.

However, when the demodulated signal S14 is a stereo broadcast signal, the microcomputer 30 supplies tuning data to the tuner circuit 22, and the tuner circuit 22 receives the tuning data.
In, the frequency band of FM broadcasting is scanned in predetermined frequency steps. Further, at this time, it is checked for each frequency of the scan whether or not the character multiplex broadcasting signal is supplied to the decoder circuit 26.

When the character multiplex broadcasting signal is supplied, the scanning of the tuner circuit 22 is stopped, and thereafter, the broadcasting station is selected, and the character multiplex broadcasting performed by the broadcasting station is performed. Character information is displayed on the LCD 28.

Thus, in the case of, the tuner circuit 2
The character multiplex broadcast is automatically searched by 2 and the character information is displayed.

As described above, the audio broadcast program and the character information program are received. In this case, the tuner circuit 12 and the tuner circuit 22 are provided especially in the above receiver. Therefore, while listening to the audio broadcast program of a certain broadcast station, the program of text information of another broadcast station can be used.

Further, since the broadcasting station which is performing the character broadcasting is automatically searched, the latest character information on the weather forecast and traffic information can be obtained.

In the above description, the processing of the microcomputer 27 can be executed in the microcomputer 30 if the processing capacity of the microcomputer 30 has a margin. Further, the switch circuit 25 may be omitted, and the demodulated signal S24 may be always supplied to the decoder circuit 26. In this case, the tuner circuit 22 may receive the same frequency as the tuner circuit 12.
Further, a speaker may be used instead of the headphones 17.

[0053]

According to the present invention, it is possible to use a program of text information of another broadcasting station while listening to a program of audio broadcasting of a broadcasting station. In addition, since the broadcasting station performing the character broadcasting is automatically searched, the latest character information can be obtained.

[Brief description of drawings]

FIG. 1 is a system diagram showing one embodiment of the present invention.

FIG. 2 is a diagram for explaining a signal format.

FIG. 3 is a diagram for explaining a signal format.

FIG. 4 is a diagram for explaining a display screen.

FIG. 5 is a diagram for explaining a display screen.

[Explanation of symbols]

10 = FM receiving circuit, 11 = antenna, 12 = tuner circuit, 13 = intermediate frequency circuit, 14 = FM demodulating circuit, 15
= Stereo demodulation circuit, 16L = amplifier, 16R = amplifier, 17 = stereo headphones, 20 = FM receiver circuit,
22 = tuner circuit, 23 = intermediate frequency circuit, 24 = FM
Demodulation circuit, 25 = switch circuit, 26 = decoder circuit,
27 = microcomputer, 28 = LCD, 30 = microcomputer, 31 = CPU, 32 = ROM, 3
3 = RAM, 34 = input port, 35 = output port, K
1 to KN = operation key

Claims (3)

[Claims] 1. A character multiplex broadcasting receiver for multiplexing character information data on a signal of an original audio broadcasting program and broadcasting the multiplexed signal. Receiving circuit, a second receiving circuit for receiving the character multiplex broadcast, a decoder circuit for extracting the data of the character information from the multiplexed signal, and a display for displaying the character information according to an output signal of the decoder circuit. An audio broadcast signal in the broadcast received by the first receiving circuit is supplied to a headphone or a speaker, and the multiplexed signal in the broadcast received by the second receiving circuit is supplied to the decoder circuit. A receiver adapted to display the character information on the display element. 2. The receiver according to claim 1, further comprising a switch circuit that selectively supplies the output signal of the first receiving circuit and the output signal of the second receiving circuit to the decoder circuit. Receiver that did. 3. The receiver according to claim 1, wherein the second receiving circuit scans the frequency band of the character multiplex broadcasting until the second character receiving circuit receives the character multiplex broadcasting.