JPH082030B2 - RDS preset receiver - Google Patents

Description

TECHNICAL FIELD The present invention relates to a preset receiver for a radio data system (hereinafter, referred to as an RDS preset receiver).

BACKGROUND ART In the case of program broadcasting of a general broadcasting station, broadcasting-related information such as information related to the program content is transmitted as data by multiple modulation, and the desired program content is demodulated on the receiving side based on the demodulated data. There is a radio data system (RDS) that enables users to select the service and provide the service to radio listeners.

In this radio data system, 57KHz, which is the third harmonic of the stereo pilot signal of 19KHz outside the frequency band of the FM modulated wave, is used as the subcarrier, and this subcarrier is filtered and biphase coded. A radio data signal is amplitude-modulated by a data signal that indicates information related to broadcasting such as contents, and the amplitude-modulated subcarrier is frequency-modulated as a main carrier for broadcasting. Is proposed by the European Broadcasting Union (EBU).

As is clear from FIG. 3 showing the baseband coding structure of the radio data signal, 104 bits correspond to 1 bit.
It is repeatedly multiplexed as a group. One group consists of four blocks of 26 bits each, each block consisting of a 16-bit information word and a 10-bit check word. In addition, each group is classified into 16 types of types 0 to 15 in 4 bits according to the content, and two versions A and B are defined for each type (0 to 15).

The formats of the type 0A and 0B groups are shown in FIGS. 4 (a) and 4 (b), respectively. In type 0A group (a), block 1 contains 16-bit program identification data (hereinafter referred to as PI data) consisting of country code, area code and program code, and block 2 contains group type code and version code. Various codes such as (B ₀ ), traffic information broadcasting station identification (TP) code, program content identification (PTY) code, etc. are stored in block 3 as station frequency data (hereinafter, referred to as AF frequency) of a network station broadcasting the same program. In the block 4, broadcast station name data (hereinafter abbreviated as PS data) are arranged. On the other hand, in the type 0B group (b), only the contents of the block 3 are different from those in the type 0A group, and PI data is arranged in the block 3.

By the way, a desired receiving station is selected as a preset station, AF data and PI data of the preset station are stored in advance in a storage area of a memory corresponding to the preset channel, and any one of the preset channels is designated. By reading the AF data and PI data stored in the corresponding storage area of the memory, this AF
There is an RDS preset receiver that receives an RDS broadcast wave having a reception frequency given by data and matching PI data.

In such an RDS preset receiver, when a preset station that has already been stored is received by tuning the reception frequency by up or down sweeping, not by the above-mentioned preset channel designation, the user presets that receiving station. Despite being a station, the operation of presetting the broadcasting-related information including the program identification data of the receiving station as a new preset station in the memory,
The same information may be stored twice in the memory, which is inconvenient for effective use of the storage area of the memory.

SUMMARY OF THE INVENTION Therefore, according to the present invention, when a preset station is received by an up / down sweep of the reception frequency that does not comply with the designation of the reception frequency stored in the memory, the data regarding the preset station is duplicated. It is an object of the present invention to provide an RDS preset receiver in which the storage area of the memory is effectively used without being stored.

[Structure of the Invention] An RDS preset receiver according to the present invention is a memory that has at least one storage area corresponding to a preset channel and is capable of storing broadcast-related information including program identification data of a preset station for each storage area. An RDS preset receiver comprising: command means for issuing a sweep command of a reception frequency, detection means for detecting reception of an RDS broadcast wave at a reception frequency swept in response to the sweep command, and the detection means Comparing the program identification data obtained from the RDS broadcast wave detected by the program identification data stored in the memory and making a match detection output when the two match, A notification notifying that the RDS broadcast wave is from a preset station corresponding to the program identification data stored in the memory in response to the coincidence detection output. It is characterized by being equipped with an intellectual means.

According to the RDS preset receiver of the present invention, the program identification data obtained from the RDS broadcast wave received by sweeping the reception frequency is compared with the program identification data of the preset station stored in the memory. , If they match,
It is announced that the received RDS broadcast wave is from the preset station corresponding to the program identification data stored in the memory.

Example Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an RDS preset receiver. In the figure, the FM multiplex broadcast wave received by the antenna 1 is selected by the front end 2 to a desired station, converted to an intermediate frequency (IF), and then transmitted via the IF amplifier 3 to FM.
It is supplied to the detector 4. The front end 2 is, for example,
A PLL synthesizer system using a PLL circuit including a programmable frequency divider is adopted, and a tuning operation is performed by controlling a frequency division ratio of the programmable frequency divider by a controller 13 described later. The detection output of the FM detector 4 is supplied to the MPX (multiplex) demodulation circuit 5,
In the case of stereo broadcasting, it is separated into L (left) and R (right) channel audio signals.

Further, the detection output of the FM detector 4 passes through the filter 6, so that the 57 KHz subcarrier amplitude-modulated by the biphase-coded data signal, that is, the radio data signal is extracted and demodulated by the PLL circuit 7. . This demodulated output is the digital (D) PLL circuit 8 and the decoder 9.
Is supplied to. The D-PLL circuit 8 generates a data demodulation clock based on the demodulation output of the PLL circuit 7. In the decoder 9, the bi-phase coded data signal which is the demodulated output of the PLL circuit 7 is decoded in synchronization with the clock generated in the D-PLL circuit 8. The lock detection circuit 10 detects the locked state and the unlocked state of the D-PLL circuit 8, and the detection output thereof detects the PLL circuit 7 and the D-PLL.
The lock range of the circuit 8 is switched and controlled.

As shown in FIG. 3, the output data of the decoder 9 is a 104-bit group unit consisting of 4 blocks of 26-bit structure, and is sequentially supplied to the group / block synchronization & error detection circuit 11. In the group / block synchronization & error detection circuit 11, the group and block are synchronized based on the 10-bit offset word assigned to the 10-bit check word of each block, and the 16-bit information based on the check word. Word error detection is performed. Then, the error-detected data is error-corrected by the error-correction circuit 12 in the next stage and then supplied to the controller 13.

The controller 13 is composed of a microcomputer, and code information of each block in the radio data sequentially input in group units, that is, radio data such as PI data, AF data, PS data, etc. related to the program content of the broadcasting station currently being received. Data information is fetched and stored in the memory 14, and based on a tuning command from the operation unit 15, a frequency division ratio of a programmable frequency divider (not shown) of a PLL circuit that constitutes a part of the front end 2 A channel selection operation is performed by controlling. Memory 14 is preset channel 1c
There is a preset storage area corresponding to each of h to 6 channels, and the AF data and PI data of the preset station are stored in these preset storage areas in association with each channel 1ch to 6ch.

Further, the level detection circuit 16 for detecting the reception signal level (electric field strength) based on the IF signal level in the IF amplifier 3
And a station detection circuit which detects a receiving station and outputs a station detection signal when the IF signal level in the IF amplifier 3 is equal to or higher than a predetermined level and the detection output of the so-called S curve characteristic in the FM detector 4 is within a predetermined level range. 17 and are provided,
The received signal level detected by the level detection circuit 16 and the station detection signal output from the station detection circuit 17 are supplied to the controller 13.

The operation unit 15 includes "1" for preset tuning.
And preset channel designation button 15 _{1-15 6} "6",
Up / down sweep command button for manual tuning
15 _U and 15 _D are provided. "1" to the any one is operated within the preset channel designation button 15 _{1-15 6} "6", the controller 13, AF data and PI stored in the area corresponding to the specified channel from the memory 14
The data is read and the AF data is programmable frequency divider (not shown) in the PLL circuit in the front end 2.
By setting to, the preset station of the reception frequency given by this AF data is selected, and when the PI data obtained from the broadcast wave of the reception station matches the PI data read from the memory 14, the preset station is finalized. Select a specific receiving station. When the preset station is selected by the preset channel selection, the channel numbers "1" to "6" are lit up and displayed on the display unit 18. Also,
When the up / down sweep command buttons 15 _U and 15 _D are operated, the controller 13 searches the broadcast wave in the reception band by changing the division ratio of the programmable frequency divider and performing the frequency sweep. .

Next, a process executed by the processor of the controller 13 during the channel selection by the up / down sweep command button 15 _U, 15 _D according to the flow chart of Figure 2. It is assumed that the preset storage area of the memory 14 stores in advance the AF data and PI data of each preset station corresponding to each of the preset channels 1ch to 6ch.

The processor uses up / down sweep command buttons 15 _U , 15
_{When the} tuning command by _D is issued (step S1), frequency sweep is performed by changing the frequency division ratio of the programmable frequency divider in the PLL circuit in the front end 2 (step S2), and then the station detection circuit 17 It is determined whether or not a receiving station exists by monitoring the output of the station detection signal from (step S3), and when the presence of the receiving station is detected, the frequency sweep is stopped (step S4). Then, it is determined whether the broadcast wave received by the receiving station is the RDS broadcast wave (step S5). Whether or not it is an RDS broadcast wave can be identified by whether or not various data can be obtained from the error correction circuit 12.

If it is an RDS broadcast wave, the processor takes in the PI data obtained from the broadcast wave (step S6), and further reads the PI data stored in the preset storage area of the memory 14 from the one corresponding to the preset channel 1ch ( In step S7), it is subsequently determined whether or not the two PI data match (step S8). If the two PI data match, the corresponding channel number is displayed on the display unit 18 (step S9). If they do not match, it is determined whether or not the PI check has been completed for all preset channels ( Step S10), if not completed for all, move to step S7 and repeat the above-mentioned processing. If no match is found after performing the PI check on all preset channels, the processing of this routine ends.

In this way, the up / down sweep command buttons 15 _U , 15 _D
When an RDS broadcast wave is received during tuning by, the PI data obtained from the RDS broadcast wave and the PI of the preset station are received.
Performs a match comparison with the data, and if they match, the PI
By displaying the channel number of the preset station corresponding to the data, the user is notified that the receiving station is the preset station, and the user is prevented from storing the data related to the same network station in the memory 14 twice. The storage area of the memory 14 can always be effectively used.

In the above embodiment, the case of manual up / down tuning is described as an example. However, up / down tuning by auto sweep tuning is also possible. It is applicable as long as it is an up / down channel selection other than preset recall.

Further, in the above-described embodiment, whether or not the received RDS broadcast wave belongs to the preset station is determined by the coincidence comparison of only PI data, but it is performed by the coincidence comparison of both AF data and PI data. It is also possible to do so.

As described above, according to the RDS preset receiver of the present invention, the program identification data obtained from the RDS broadcast wave received by sweeping the reception frequency and the program identification data of the preset station stored in the memory Are compared, and if they match, it is announced that the received RDS broadcast wave is from the preset station corresponding to the program identification data stored in the memory. Since it is possible to inform the user that the station is a preset station, it is possible to prevent the preset station for the received broadcast station from being preset again, and to prompt the user not to store the data regarding the same network station in the memory twice.
As a result, the storage area of the memory can always be used effectively.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an RDS preset receiver according to the present invention, FIG. 2 is a flow chart showing a processing procedure for manual channel selection, and FIG. 3 is a diagram showing a baseband coding structure of radio data. FIG. 4 is a diagram showing formats of group types 0A (a) and 0B (b). Explanation of symbols of main parts 2 …… Front end, 4 …… FM detector 5 …… Multiplex demodulation circuit 8 …… Digital PLL circuit 13 …… Controller, 14 …… Memory 15 …… Operating section, 18 …… Display Department

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Akira Hayama, inventor 25 Nishi Nishimachi, Yamada, Kawagoe City, Saitama Prefecture 1 Pioneer Co., Ltd. Kawagoe Factory (72) Inventor Yoshiro, 25 Nishi Nishi, Yamada, Kawagoe City, Saitama Prefecture 1 Pioneer Co., Ltd. Kawagoe Factory (72) Inventor Kawabata, etc. 1-4-1 Meguro, Meguro-ku, Tokyo Pioneer Co., Ltd. (56) References JP-A 64-54939 (JP, A)

Claims (3)

[Claims] 1. An RDS preset receiver having at least one storage area corresponding to a preset channel and having a memory capable of storing broadcast-related information including program identification data of a preset station for each storage area. Command means for issuing a sweep command of the reception frequency, and the reception frequency swept in response to the sweep command
Comparing the detection means for detecting the reception of the RDS broadcast wave with the program identification data obtained from the RDS broadcast wave detected by the detection means and the program identification data stored in the memory, the two are in agreement. In this case, the comparison means for producing a coincidence detection output and, in response to the coincidence detection output of the comparison means, announces that the RDS broadcast wave is from a preset station corresponding to the program identification data stored in the memory. An RDS preset receiver characterized by being provided with a notification means. 2. The notification means displays the channel number of a preset station corresponding to the coincident program identification data in response to the coincidence detection output.
RDS preset receiver as described. 3. The broadcast-related information includes frequency data indicating a reception frequency of the preset station, and the comparing means further compares the reception frequency of the RDS broadcast wave with the frequency data stored in the memory. 2. The RDS preset receiver according to claim 1, wherein the coincidence detection output is performed after the both coincide with each other.