JPH0897740A - Fm multiplex broadcast receiver - Google Patents

Abstract

PURPOSE: To receive and display the same FM multiplex broadcast program as that before revision of a received frequency without selective operation of the FM multiplex broadcast program after the received frequency is revised. CONSTITUTION: When the received frequency is revised, a processor 17 judges whether the reception frequency after revision is matched with a relay station frequency of an FM station before revision stored in a memory 23 or a substitute station frequency or a broadcast enterprise of the reception frequency after revision is matched with a broadcast enterprise of an FM station before the revision and the processor 17 receives and displays the FM multiplex broadcast program specified by a service category number Si and a program number PNj set by an operation section 19 before the revision when any condition is satisfied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention separates FM multiplex broadcast program information, which is identified by a service category and a program number, from an FM broadcast signal, demodulates it and displays it on a display screen.
The present invention relates to an M multiplex broadcast receiver, and more particularly, to an FM multiplex broadcast receiver capable of continuously receiving and displaying an FM multiplex broadcast program that has been received and displayed until the reception frequency is changed.

[0002]

2. Description of the Related Art In recent years, teletext programs (weather forecasts, news, etc.) and traffic information programs (traffic information for each region and highway) are multiplexed on an FM broadcast signal and transmitted to a display device of an FM receiver. The display service is being started. In such FM multiplex broadcasting, the FM transmitting station multiplexes a large number of FM multiplex broadcast program information identified by the service category Si and the program number PNj into the FM broadcast signal and transmits it. Therefore, by inputting the service category Si and the program number PNj by the key provided in the FM multiplex broadcast receiver and specifying the desired FM multiplex broadcast program, the FM multiplex broadcast receiver receives the specified broadcast program, Demodulate and display on display device.

[0003]

By the way, the conventional FM
In the multiplex broadcast receiver, if the reception frequency is changed and another FM frequency is selected, all the multiplex broadcast data in the memory is cleared once, and then new multiplex broadcast data is received again.
Thereafter, the service category Si and the program number PNj are input to specify the desired FM multiplex broadcast program and display it on the display device. Therefore, for example, when it is desired to continue receiving / displaying a news program, a news program selection operation (Si, PNj is performed each time the reception frequency is changed.
Input), which is inconvenient because the number of operations is increased, and there is a problem that safety during driving is lacking. From the above, the first object of the present invention is to provide an FM multiplex broadcast receiver capable of receiving and displaying the same FM multiplex broadcast program as before the change of the receiving frequency without changing the FM multiplex broadcast program when the receiving frequency is changed. Is to provide. A second object of the present invention is to provide an FM multiplex broadcast receiver that can easily select and display the same FM multiplex broadcast program as before changing the receiving frequency when the receiving frequency is changed.

[0004]

According to the present invention, the above-mentioned problems are solved by setting the service category Si and the program number P.
A means for separating and demodulating the information of the FM multiplex broadcast program specified by Nj from the FM broadcast signal and displaying it on the display screen, and a relay station among the additional information transmitted and multiplexed with the FM broadcast signal currently being received. Storage means for storing frequency data, alternative station frequency data, and broadcaster number, reception frequency changing means for changing the reception frequency, and when the reception frequency is changed, the changed reception frequency is stored in the relay. A judgment means for judging whether it matches the station frequency or the alternative station frequency, or whether the broadcaster of the received frequency is the same as the stored broadcaster, and if any one of the conditions is satisfied, , An FM having means for receiving and displaying an FM multiplex broadcast program specified by the set service category Si and program number PNj
Achieved by multiple broadcast receivers.

[0005]

The information of the FM multiplex broadcast program specified by the set service category Si and the program number PNj is set to FM.
It is separated from the broadcast signal, demodulated and displayed on the display screen, and among the additional information sent together with the program information in the FM broadcast signal currently being received, the relay station frequency data, the alternative station frequency data, and the broadcaster. Store the number in memory. When the reception frequency is changed in such a state, the changed reception frequency matches the stored relay station frequency or alternative station frequency, or the broadcaster of the reception frequency stores the broadcast. If it is the same as the business operator, and if any one of the conditions is satisfied, the FM multiplex broadcast program specified by the service category Si and the program number PNj set before the reception frequency change is received. indicate.

[0006] Broadcasting stations generally form networks such as NHK and JFN, and in such networks, service numbers and program numbers of multiple broadcast programs are unified and operated. That is, within the same network, FM
Even if the frequencies are different, the correspondence between multiple broadcast programs, service numbers, and program numbers is the same system. Therefore, it is checked whether the FM broadcasting station after the change of the reception frequency is a relay station or an alternative station of the FM broadcasting station before the change, or whether the broadcasting companies are the same (same network), and the FM station after the change is In the case of the relay station or the alternative station of the FM station before the change or the same network station, the FM multiplex broadcast program specified by the service category Si and the program number PNj set before the frequency change is received and displayed. With this configuration, even if the reception frequency is changed, the same FM as before the reception frequency is changed without performing the FM multiplex broadcast program selection operation.
Multiple broadcast programs can be received and displayed. When none of the above conditions is satisfied, the reception frequency F
When the FM multiplex broadcast program information is multiplexed on the M broadcast signal, the table of contents of the FM multiplex broadcast program is displayed on the display device, and the FM multiplex broadcast program information is not multiplexed on the FM broadcast signal of the reception frequency. Stops displaying the FM multiplex broadcast program. By automatically displaying the table-of-contents program in this manner, the broadcast program can be easily selected by referring to the table of contents.

[0007]

【Example】

(a) Overall Configuration FIG. 1 is a configuration diagram of an FM multiplex broadcast receiver of the present invention.
The FM multiplex broadcast receiver receives the FM broadcast signal and
FM multiplex broadcast data (FM multiplex broadcast program information) such as teletext information and traffic information which are multiplexed and transmitted with a broadcast signal
Is separated and demodulated and displayed on a display device. As shown in FIG. 2, FM multiplex broadcast data includes 272 blocks per frame, 190 blocks out of 272 blocks are data blocks, 82 blocks are parity blocks transmitting only parity, and parity blocks are included in the data blocks. It is distributed and arranged.

Each data block is composed of a 16-bit block identification code BIC (Block Identify Code), 176-bit data, a 14-bit CRC code, and an 82-bit error detection / correction parity (horizontal code). ing. The parity block is a 16-bit block identification code BIC and a 190-bit parity (vertical code).
And 82-bit error detection and correction parity (horizontal code)
It consists of and. The identification code of the data block of the first 13 blocks is BIC1, the identification code of the data block of the next 123 blocks is BIC3, the identification code of the data block of the next 13 blocks is BIC2, and the last Of the 123 blocks, the identification code of the data block is BIC3 and the identification code of the parity block is BIC4. The 16-bit block identification codes BIC1 to BIC4 have, for example, the block synchronization pattern shown in FIG.

Block synchronization can be achieved by detecting the block identification code for each block, and 27
Every 2 blocks (the block identification code BIC4 is followed by BI
Frame synchronization can be achieved (by detecting C1). In other words, block synchronization is lost when the number of times that the block identification code cannot be detected in the above order occurs at a predetermined rate, and frame synchronization is lost when frame synchronization cannot be achieved at a predetermined rate. Also, because the data block contains a CRC code, a CR
C check can be performed. Furthermore, since the parity (vertical code, horizontal code) for error detection and correction is included, error detection and error correction processing can be performed using these parities.

In FIG. 1, 1 is an antenna, 4 is a front end (F / E), which has an antenna tuning circuit, a high frequency amplifier circuit, a local oscillator, a mixer, etc., which are not shown, 5 is a PLL circuit, and 6 is A low pass filter, 7 is an intermediate frequency amplifier / FM detector (IF / DET). PLL
The circuit 5, the low-pass filter 6 and the local oscillator built in the front end 4 constitute an electronic tuning device, and the local oscillator receives the reception frequency (the frequency of the FM broadcasting station selected by the tuning operation).
Is oscillated at a frequency according to the above, and the mixer in the front end 4 outputs an intermediate frequency signal.
A noise canceller / stereo demodulation circuit (NC / MPX) 11 performs noise cancellation and stereo demodulation.
Reference numeral 12 is a filter circuit for extracting an L-MSK modulation signal component from the FM detection signal, 13 is an L-MSK demodulation circuit for performing delay detection on the L-MSK modulation signal to reproduce a bit clock and demodulate a bit data string, and 14 is A synchronization circuit for detecting block synchronization and frame synchronization, 15 is an error detection / correction unit, and a CRC check unit 15a and an error correction circuit 15 are provided.
b. The CRC check unit 15a performs a CRC check for each block, and the error correction circuit 15b performs PN decoding on the bit data string based on the block synchronization and frame synchronization detection signals input from the synchronization circuit, and then converts it into a predetermined format. While being temporarily stored in the RAM 16 while being separated, syndrome data is generated using a parity code, and error correction is performed by a majority decision for the syndrome.

Reference numeral 17 denotes a processor CPU, which performs tuning control according to a tuning operation, various processes based on FM multiplex broadcast data, and continuous reception control of FM multiplex broadcast programs when a receiving frequency is changed. Is the received F
A memory for storing M multiplex broadcast program information (text information, road traffic information, etc.), and 19 is an operation for the user to select a channel or call a desired program (road traffic information, text broadcasting, etc.) Part, 20 is a display processor,
20a is a video RAM for storing images, 21 is a display device for displaying teletext programs (news, weather forecast, etc.) and road traffic information on the screen, 22 is a display unit for displaying broadcast frequency and station name, and 23 is for CPU Is the work memory of. The operation unit 19 is provided with various keys, for example, a key 19a (MPX key) for setting the FM multiplex broadcast receiver into a reception mode for multiplex broadcast programs, a key 19b (Si key) for inputting the service category Si, and a program number. A key 19c (PN key) for inputting PNj is provided. The work memory 23 stores a service category Si and a program number PNj that specify the multiplex broadcast program currently being received and displayed.
Additional information (relay station list RFL, alternative station list AF) multiplexed and transmitted from the FM broadcast station
L, broadcaster name SNW), etc. are stored.

(B) Multiplex Broadcast Program Information The data block (FIG. 2) of FM multiplex broadcast data contains various broadcast program information such as text broadcast and traffic information. As shown in FIG. 4, each program can be identified by a service category Si, an information type (currently undefined), and a program number PNj. Service category Si is teletext (news, weather forecast, other service information),
Traffic information, additional information, index information, etc. are designated. Si = 1 or 2 designates teletext, Si = 4 designates traffic information, Si = D designates additional information, and Si = E designates index information. It Each service category (Si
= 1, 2, 4), there are several information types (currently undefined), and each information type has a program number P of 0 to 255.
Nj is assigned, and PNj = 0 is fixed as the program number of the table of contents program. FIG. 4 shows the correspondence between the program number of the traffic information and the program content. For example, PNj = 0 is a table-of-contents program, PNj = 1 is a Tomei Expressway traffic information program, and PN.
j = 2 is a traffic information program on the Metropolitan Expressway, ..., PNj = 5
0 is a traffic information program in the Setagaya area, PNj = 51 is a traffic information program in the Yokohama area, and so on. The table of contents program displays the correspondence between all program numbers in the service category and program contents.

To receive and display a predetermined broadcast program, the key 19a on the operation unit 19 is operated to enter the multiplex broadcast mode,
Then, the broadcast program may be specified by the S key 19b and the program number selection key 19c provided on the operation unit 19. As shown in FIG. 5, the additional information of Si = D is divided into the segments 1 to F. The segment = 1 identifies the broadcaster (company number) of the FM broadcast currently being received, and the segment = 8 indicates the current The relay station list (relay frequency, relay station name) of the FM broadcasting station being received is specified,
The segment = A specifies the alternative broadcast station list (reference station frequency, alternative station frequency) of the FM broadcast station currently being received. At each alternative station, the service category and program number of the multiplex broadcast program are unified. That is, even if the FM frequencies are different within the same alternative station group, the correspondence between the multiple broadcast program and the service category / program number (Si / PNj) is the same. Similarly, in the base station and each relay station group, the correspondence between the multiple broadcast program and the service category / program number (Si / PNj) is the same.

Further, in the same network, the correspondence between the multiple broadcast program and the service category / program number (Si / PNj) is the same even if the FM frequencies are different. This is because a broadcasting station generally forms a network like NHK or JFN, and such a network operates the service category and program number of a multiple broadcast program in a unified manner. Whether or not the networks are the same
It can be checked by checking whether the broadcasters are the same. From the above, when the reception frequency is changed, the changed FM station is the relay station of the FM station before the change, or the changed FM station is the alternative station of the FM station before the change,
It is checked whether the FM broadcasting stations before and after the frequency change configure the same network, and if one of the conditions 1 to 3 is satisfied, the FM multiplex broadcast program specified by the service category Si and the program number PNj before the reception frequency change is selected. Reception
If shown, the display contents can be the same as before the frequency change.
That is, when the reception frequency is changed, the same FM multiplex broadcast program as before the change of the reception frequency can be received and displayed without performing the operation of selecting the FM multiplex broadcast program. Si =
The index information of E is a list in which the service category Si is associated with all program numbers of the service category.

(C) Overall Operation FIG. 6 is a flow chart of multiple broadcast program reception control of the present invention. The processor 17 inputs the frequency data corresponding to the FM station of the frequency f ₁ selected by the tuning operation to the PLL circuit 5 to perform electronic tuning control. As a result, the front end 4 inputs the intermediate frequency signal corresponding to the reception frequency f ₁ to the intermediate frequency / FM detector 7. Intermediate frequency / FM detector 7
Performs intermediate frequency amplification and FM detection on the input signal,
Further, the noise canceller / stereo demodulation circuit 11 performs noise cancellation and demodulation processing of a stereo signal. on the other hand,
The filter circuit 12 extracts the L-MSK modulated signal component from the FM detection signal, and the L-MSK demodulation circuit 13 outputs the L-MSK signal.
The K-modulated signal is subjected to differential detection to reproduce the bit clock and demodulate the bit data string. The synchronization circuit 14 detects block synchronization and frame synchronization using the bit clock and bit data sequence output from the L-MSK demodulation circuit 13, and the error detection / correction unit 15 inputs the bit clock, bit data sequence and synchronization signal. Then, error detection and correction processing is performed on the input data, and the multiplex broadcast data is input to the processor 17. The processor 17 stores the input multiplex broadcast data in the memory 18.

In this state, the multiple broadcast receiving mode is set by operating the key 19a, and then the keys 19b,
Service category Si and program number PN using 19c
When the broadcast program is specified by inputting j, the processor 17 reads out data corresponding to the specified broadcast program from the memory 18 and inputs it to the display processor 20, develops it into an image and displays it on the display device 21. . Further, the processor 17 identifies the service category Si and the program number PNj that specify the multiplex broadcast program being received and displayed, and
The work memory 23 stores the additional information (relay station list, alternative station list, broadcaster name) transmitted together with the program information in the FM broadcast signal being received.

In this state, the tuning switch (not shown) of the operation unit 19 is operated to change the reception frequency from f ₁ to f ₂ (step 101). The processor 17 refers to the relay station list stored in the work memory 23 and checks whether the newly selected reception frequency f ₂ is the relay station frequency of the FM station before the frequency change (step 102).
If it is not the relay station frequency, the reception frequency f newly selected by referring to the alternative station list stored in the work memory
It is checked whether ₂ is the alternative station frequency of the FM station before frequency change (step 103). If the frequency is not the alternative station frequency, does the business number included in the additional information multiplexed and sent with the currently received FM broadcast signal extracted and whether it matches the business number stored in the work memory 23? Check (step 104). If they are different, that is, if the FM stations before and after the frequency change do not form the same network, it is checked whether the FM broadcast station of the reception frequency f ₂ is a multiple broadcast station (step 105). If it is not the FM multiplex broadcasting station, the contents of the memory 18 are cleared and the reception / display of the multiplex broadcasting is stopped (step 106). If it is the FM multiplex broadcasting station, the FM multiplex broadcasting data is stored in the memory 18 and then the frequency is stored. The table of contents program of the service category Si set before the change is displayed on the display device 21, and thereafter, the program selection operation is awaited (step 107).

On the other hand, if the relay station frequency is used in step 102, the alternative station frequency is used in step 103, or the FM stations before and after the frequency change form the same network in step 104, the reception frequency is changed. The previously set service category Si and the program number PNj are adopted (step 10
8) These service category Si and program number PNj
The FM multiplex broadcast program specified by
8 (step 109). Then, the index information (Si = E) transmitted by being multiplexed with the FM broadcast signal is received, and it is checked whether or not the above-mentioned Si / PNj combination exists in the index information (step 110). , The table of contents program of the service category Si is displayed on the display device 21, and thereafter, the program selection operation is awaited (step 107). If it exists, Si / P before changing the reception frequency
The program information designated by Nj is read from the memory 18, input to the display processor 20, developed into an image, and displayed on the display device 21 (step 111).
Although the present invention has been described above with reference to the embodiments, the present invention can be variously modified according to the gist of the present invention described in the claims, and the present invention does not exclude these.

[0019]

As described above, according to the present invention, whether the FM broadcasting station after the reception frequency change is a relay station or an alternative station of the FM broadcasting station before the change, or whether the broadcasting companies are the same (same network) If the FM station after change is a relay station or an alternative station of the FM station before change or the same network station, the FM specified by the service category Si and the program number PNj set before frequency change Since the configuration is such that the multiplex broadcast program is received and displayed, even if the received frequency is changed, the same FM multiplex broadcast program as before the reception frequency change can be received and displayed without selecting the multiplex broadcast program. it can. Further, according to the present invention, when the changed FM station is neither a relay station of the FM station before the change, a substitute station, or the same network station, the table of contents of the FM multiplex broadcast programs is displayed on the display device. Since it is configured to be automatically displayed, the multiple broadcast program can be easily selected by referring to the table of contents.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an FM multiplex broadcast receiver of the present invention.

FIG. 2 is a frame configuration diagram of FM multiplex data.

FIG. 3 is a pattern explanatory diagram of a block identification code BIC.

FIG. 4 is a relationship diagram between service category Si / program number PNj and a broadcast program.

FIG. 5 is an explanatory diagram of additional information.

FIG. 6 is a flow chart of multiple broadcast program reception control of the present invention.

[Explanation of symbols]

 17-Processor 19-Operation unit 23-Work memory RFL-Relay station list AFL-Alternative station list SNW-Business operator number

Claims (2)

[Claims] 1. An FM multiplex broadcast signal currently being received in an FM multiplex broadcast receiver that separates and demodulates information of an FM multiplex broadcast program identified by a service category and a program number from an FM broadcast signal and displays it on a display screen. Storage means for extracting and storing the relay station frequency data, the alternative station frequency data, and the broadcaster number from the additional information multiplexed and sent together with the program information, and the reception frequency changing means for changing the reception frequency. When the received frequency is changed, the changed received frequency matches the stored relay station frequency or alternative station frequency, or the broadcaster of the received frequency is the stored broadcaster. The determination means for determining whether they are the same and, if any one of the above conditions is satisfied, the service category set before the reception frequency is changed. FM multiplex broadcasting receiver having means for receiving and displaying the FM multiplex broadcast program specified by the program number. 2. If none of the above conditions are satisfied, and if the FM multiplex broadcast program information is multiplexed in the FM broadcast signal of the changed reception frequency, the index program of the FM multiplex broadcast program is displayed on the display device. The FM multiplex broadcast reception according to claim 1, further comprising: means for stopping the display of the FM multiplex broadcast program when the FM multiplex broadcast program information is not multiplexed on the FM broadcast signal of the selected frequency. Machine.