JP3049925B2 - Receiving machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver using RDS data.

[0002]

2. Description of the Related Art Some FM broadcasting stations in Europe add RDS data to an original audio signal.

[0003] The RDS data is a collection of digital data related to a broadcasting station, a program, and the like. The RDS data includes a PI code and a program identification code. It has a country code, a program code, and the like. PS data キ ャ ラ ク タ Character data indicating the broadcasting station name. PTY code @ Program content identification code. news,
Shows the program contents such as light music, education, sports, and information. Such data is included.

Then, the RDS data is subjected to an encoding process for error correction, and the RDS data subjected to the encoding process has a frequency of 57 kHz (this is a value three times the frequency of the stereo pilot signal of 19 kHz). The subcarrier signal is balanced-modulated, and the modulated signal is added to a monaural signal or a stereo composite signal and frequency-multiplexed, and the multiplexed signal is transmitted by an FM wave.

[0005] In the following description, a broadcasting station that also transmits RDS data is called an "RDS station".

Therefore, if RDS data is used,
Pressing the auto preset key: 1. Scans and receives the FM broadcast frequency band from its lowest frequency.

[0007] 2. Upon receiving the RDS station, data on the received frequency is stored in a memory.

[0008] 3. The operation of the above two items is repeated up to the highest frequency of the frequency band. , And the RDS station can be automatically preset.

In the following description, such an operation of automatically presetting an RDS station using RDS data is called "RDS auto preset".

[0010]

However, since the frequency band of FM broadcasting in Europe is 87.5 to 108 MHz and the frequency interval is 50 kHz, about 100 FM broadcasting can be received on average. Therefore, when the RDS auto-preset is executed, a considerable number of broadcast stations are stored in the memory, but it is impossible to predict the number of the stored broadcast stations. Therefore, if the memory capacity is small, the FDS
The memory becomes full before scanning all of the M broadcast bands.

Of course, if the capacity of the storage memory is made sufficiently large, all of the results of the RDS auto-preset can be stored in the memory.

However, in view of the actual radio wave situation in Europe, a large number of relay stations (satellite stations) are installed, and at least 3 to 5 stations of the same program can be received at different frequencies. Therefore, when the memory capacity is increased, all of the results of the RDS auto preset can be stored in the memory. At this time, many relay stations are also stored, that is, the same program having a different frequency but the same program is stored. Are stored in duplicate.

In the case of such an RDS auto-preset, the memory is not effectively used,
The number of tuning keys becomes a problem. Furthermore, even if the listener presses another channel selection key, the same program may be selected (although the frequency is different), resulting in extremely poor usability.

When the RDS auto-preset is executed, the RDS stations are received in order of frequency, and the broadcast stations are simply stored in the memory in order of the frequency. It is necessary to confirm or memorize the station, which also makes usability worse.

The present invention seeks to eliminate the above problems.

[0016]

Now, when the entire FM broadcast wave band to be scanned is scanned, for example, as shown in FIG. 5, the broadcast station "HR1" can receive at two frequencies, and the broadcast station "WDR2""Can be received at three frequencies, and other broadcast stations" SWF2 "," HR3 ", etc. can each be received at only one frequency. Also, the reception level of each broadcasting station is as shown in the figure.

Then, in the present invention, the broadcasting station "H"
Regarding “R1”, since the reception level of the “HR1” station of the first frequency is higher than the reception level of the two, the frequency data for receiving the “HR1” station of the first frequency is stored in the memory. Remember.

For the broadcast station “WRD2”, 3
Of these two stations, the “WRD2” station of the second frequency has the highest reception level, so the “WRD2” station of the second frequency
2) Frequency data for receiving a station is stored in a memory.

Further, other broadcasting stations "SWF2", "HR
"3" can be received at only one frequency, and the frequency data is stored in the memory as it is.

The frequency data stored in the memory is
The order is not the frequency order but the station name of the broadcast station.

That is, in the present invention, when the reference numerals of the respective parts correspond to the embodiments described later, various data S32 such as a program code and character data indicating a broadcast station name are provided.
Is transmitted together with the main signal S17, a receiver circuit 10 of a synthesizer system, and a demodulation circuit 32 for demodulating various data S32 from the broadcast wave signal S12 received by the receiver circuit 10. Detection circuit 3 for detecting the reception level of the broadcast wave signal S12 received by the reception circuit 10.
5, a memory 44, and a preset key KRP.
When the preset key KRP is operated, the receiving frequency f12 of the receiving circuit 10 is changed for each predetermined frequency step to scan the broadcast frequency band, and the broadcast wave signal S12 having various data S32 is scanned by this scan. Data N of the frequency to be received is obtained and stored in the memory 44. However, when the program code or the character data is equal in a plurality of broadcast wave signals S12,
Out of the plurality of broadcast wave signals S12, the data N of the frequency of the broadcast wave signal S12 having the maximum reception level indicated by the detection circuit 35 is
It is stored in the memory 44. Also, RDS stations are listed in the order of their names.
And stored in the memory 44 .

[0022]

With respect to a plurality of broadcasting stations broadcasting the same program, the data N of the frequency of the broadcasting station having the highest reception level is stored in the memory 44. Therefore, since the broadcasting stations broadcasting the same program are not stored in the memory 44 in duplicate, the memory 44 is effectively used and the usability is improved. Also, the RDS station receives
Are stored in the memory 44 in the order of station name, not in the order of signal frequency.
Therefore, when the listener selects a channel using the tuning key,
Easy to understand which RDS station is registered in the station key
In addition, usability is improved from this point.

[0023]

In FIG. 1, a receiving circuit 10 is of a synthesizer type, and a reception signal of an antenna 11 is supplied to an antenna tuning circuit 12 of an electronic tuning type, and an FM broadcast wave signal of a target frequency f12 is obtained. S12 is taken out.

The signal S12 is transmitted to the high-frequency amplifier 1
3 to the mixer circuit 14 and
An oscillation signal S21 having a frequency f21, for example, f21 = f12 + 10.7 [MHz] (1) is extracted from O21, and this signal S21 is supplied to the mixer circuit 14 as a local oscillation signal. The frequency is converted to a signal S14 (the intermediate frequency is 10.7 MHz). Then, the intermediate frequency signal S14 is supplied to the FM demodulation circuit 16 through the intermediate frequency amplifier 15, and an audio signal (monaural signal or stereo composite signal) S17 and a modulated signal S31 modulated by the RDS data are taken out. The signal S17 is the low-pass filter 1
7 and the speaker 19 through the low frequency amplifier 18.

At this time, the VCO 21 is connected to the circuit 2
Together with 2 to 25, the PLL 20 is configured. That is, the signal S21 from the VCO 21 is supplied to the variable frequency dividing circuit 22 and divided into a frequency of 1 / N, and this frequency-divided signal is supplied to the phase comparing circuit 23 and the oscillation circuit 24
An oscillation signal having a reference frequency, for example, a frequency of 50 kHz, is taken out from the control circuit 23, and the oscillation signal is supplied to the comparison circuit 23. The output voltage of the filter 25 is supplied to the tuning circuit 12 as a tuning voltage.

Therefore, in the steady state, the frequency of the frequency-divided signal from the frequency-dividing circuit 22 and the frequency of the oscillation signal of the oscillation circuit 24 are equal, and the frequency f21 of the oscillation signal S21 at this time is f21 = N × 50. [KHz] ‥‥‥ (2), and from equations (1) and (2), f12 = N × 0.05−10.7 [MHz].

Therefore, if the frequency division ratio N is changed by "1" between 1964 and 2374, the local oscillation frequency f
21 changes from 98.2 MHz to 118.7 MHz at intervals of 50 kHz, so that the reception frequency f12 changes the frequency band of 87.5 MHz to 108.0 MHz in a frequency step of 50 kHz and the frequency division ratio N
Will change correspondingly.

Further, reference numeral 40 denotes a microcomputer for system control, 41 denotes its CPU, 42
Is a ROM in which various processing routines and, for example, the processing routine 100 shown in FIGS. 2 and 3 are written, 43 is a RAM for a work area, and 44 is a memory for storing various data. Are connected to the CPU 41 through the system bus 49.

In this case, the memory 44 is a ROM capable of electrically erasing and writing data.
Alternatively, although not shown, the memory is a RAM backed up by a battery, that is, the memory 44 is a non-volatile memory, and can hold written data even when the power is turned off.

The memory 44 stores the result of the RDS auto-preset. The memory 44 stores, for example, a frequency table FTBL as shown in FIG.
Is prepared. That is, this frequency table FTBL
Is divided into three pages A to C, and each of the pages A to C has an area 0 to 10 stations.
It is divided into nine. In each of the areas 0 to 9, frequency data for receiving a broadcast of each frequency and PS data (character code indicating a broadcast station name) included in the RDS data are registered, as described later. .
In the example of FIG. 4, the frequency division ratio N is registered as the frequency data.

Therefore, in this frequency table FTBL, the division ratio N and PS data for 30 stations can be registered. If a page and an area are specified, the area from the area of the specified page is registered there. The frequency division ratio N and the PS data can be read.

Further, the memory 44 also stores the last channel data, that is, the frequency division ratio N of the broadcast station that was received when the power was last turned off.

Reference numeral 51 is an output port, 52 and 53 are input ports, 54 is a key interface circuit, and these circuits 51 to 54 are connected to the CPU 41 through a system bus 49.
It is connected to the. The port 51 is connected to the frequency dividing circuit 22.
, And a program described later is executed to set the frequency dividing ratio N in the frequency dividing circuit 22.

Further, a part of the FM demodulated output and the intermediate frequency signal S14 is supplied from the demodulation circuit 16 to the detection circuit 35, and a signal S35 indicating the reception level (reception electric field strength) of the reception signal S12 is extracted. The detection signal S 35 is A / D converted by the A / D converter 36 and then supplied to the port 52.

The modulated signal S31 from the demodulation circuit 16
Is supplied to the demodulation circuit 32 through the band-pass filter 31 to demodulate the RDS data S32, and the RDS data S32 is supplied to the decoder circuit 33 for error correction, and then supplied to the port 53. Further, at this time, a signal S33 indicating the result of error correction of the RDS data S32, that is, an error flag S33 indicating the presence or absence of an error in the RDS data S32 output from the decoder circuit 32, is extracted from the decoder circuit 33. Is also supplied to the port 53.

Further, the interface circuit 54 includes:
As operation keys, an up key KUP, a down key KDW, a page key KPG, an RDS auto preset key KRP, and channel selection keys KN0 to KN9 are connected. In this case, the keys KUP to K
Each of N9 is configured by a non-lock type push switch.

Then, the up key KUP and the down key K
DW is a key for raising or lowering the reception frequency f12 in 50 kHz steps when these are pressed, and a page key KPG is a key for selecting pages A to C of the frequency table FTBL of the memory 44. . Furthermore, RD
The S auto-preset key KRP is a key for executing RDS auto-preset, and includes channel selection keys KN0 to KN9.
Is a key for selecting a broadcast station whose key is RDS auto-preset when pressed.

Reference numeral 55 denotes a display controller;
A display device 61 digitally displays a broadcast station name, a reception frequency, and the like.

According to such a configuration, the CPU 41
The following operation or processing is performed by executing the program of the OM 42. In the following description, “broadcast station” includes “relay station”.

<< Power On >> When the power is turned on, the data of the last channel, that is, the frequency division ratio N of the broadcast station received when the power was last turned off is stored in the memory 44.
And the frequency dividing ratio N is set in the frequency dividing circuit 22 through the port 51.

Therefore, when the power is turned on, the broadcasting station that was received when the power was last turned off is received.

Next, predetermined data is supplied to the display controller 55, and data relating to the currently receiving broadcasting station, for example, the receiving frequency is displayed on the display device 61. Further, the receiving broadcasting station is set to the RDS station. If,
The PS data included in the RDS data S32 is supplied to the controller 55, and the broadcast station name is displayed on the display device 61. After that, the CPU 41 waits for a key input from the keys KUP to KN9.

<< Tuning by key KUP or key KDW >>
When the CPU 41 waits for a key input from the keys KUP to KN9 and presses the up key KUP or the down key KDW, the frequency division ratio N set in the frequency dividing circuit 22 through the port 51 becomes smaller than the current value. Is also increased or decreased by “1”. However, when the frequency division ratio N reaches its maximum value or minimum value, it is fixed at the maximum value or minimum value.

Therefore, each time the key KUP or KDW is pressed, the reception frequency f12 rises or falls by 50 kHz each time the key KUP or KDW is pressed, and it is possible to select a broadcast of an arbitrary frequency. After this channel selection, the frequency division ratio N is stored in the memory 4
4 is written as the last channel data at a predetermined address.

<< RDS Auto Preset >> To perform RDS auto preset, press the RDS auto preset key KRP.

Then, the processing of the CPU 41 is switched to the routine 10
0, step 101, then step 10
In Step 2, a storage area for the division ratio N, RS data, PI code, and the detection signal S35 for 30 stations is secured in the work area of the RAM 43, and this area is cleared. Frequency 8
A minimum division ratio N (= 1964) corresponding to 7.5 MHz is prepared.

Next, the process proceeds to step 111, in which the frequency dividing ratio N is set in the frequency dividing circuit 22 through the port 51, and the receiving circuit 10 receives the frequency f12 corresponding to the frequency dividing ratio N. State. In this case, the receiving frequency f12 is set to the lowest frequency of 87.5 MHz based on the frequency division ratio N prepared in step 103. continue,
The process proceeds to step 112. In this step 112, by checking the detection signal S35, it is determined whether or not the reception level is correctly tuned to the broadcast wave whose level is equal to or higher than the specified value. The process proceeds from step 112 to step 113.

In this step 113, R
By checking the presence or absence of the DS data S32, it is determined whether or not the broadcast station received in step 111 is an RDS station. The check of the presence or absence of the RDS data S32 is based on the ID included in the RDS data S32.
This can be done with data.

If the result of this check is that an RDS station has been received, the process proceeds from step 113 to step 114, where the RD
It is checked whether a PI code equal to the PI code included in the S data S32 exists in the PI code area of the RAM 43.

In this case, since the broadcasting station and the relay station are the same program, the PI code is the same. Alternatively, PI
If the codes are equal, there is a relationship between the broadcast station and its relay station. Then, as described later, a PI code equal to the PI code included in the RDS data S32 currently being received is R
When the broadcast station does not exist in the AM 43, the frequency division ratio N of the broadcast station of the same program as that of the broadcast station currently being received is not yet stored in the RAM 43. Also, the RDS data S32 currently being received
Is stored in the RAM 4
3, the frequency division ratio N of the broadcasting station of the same program as the currently receiving broadcasting station is already stored in the RAM 43.

Therefore, in step 114, the process of checking whether or not the PI code equal to the PI code included in the currently received RDS data S32 exists in the RAM 43 is performed by broadcasting the same program as the currently received program. This is equivalent to checking whether the division ratio N of the station is stored in the RAM 43 or not.

If it is determined in step 114 that the PI code equal to the PI code included in the RDS data S32 does not exist in the RAM 43,
The process proceeds from step 114 to step 115. In this step 115, the frequency division ratio N, PI code and PS data of the currently receiving broadcasting station are stored in the RAM 43, and the reception level of the reception signal S12 at this time is changed. The indicated detection signal S35 is also stored in the RAM 43. Then, the process proceeds to step 118.

Therefore, according to steps 114 and 115, when a broadcast station broadcasting a program different from the broadcast station already stored in RAM 43 is received,
The division ratio N, PS data and PI of the received broadcast station
The code is stored in the RAM 43, and the detection signal S35 of the reception level of the broadcasting station is also stored in the RAM 43.

On the other hand, if it is determined in step 114 that a PI code equal to the PI code included in the RDS data S32 is present in the RAM 43, the process proceeds from step 114 to step 116. The signal S35 indicating the reception level of the currently broadcasting station is compared with the signal S35 indicating the reception level of the broadcasting station having the same PI code stored in the RAM 43 in step 115, and the reception level of the currently receiving broadcasting station is compared. If it is higher than the broadcast station reception level stored in the RAM 43, the process proceeds from step 116 to step 117.

Then, in step 117, the frequency division ratio N of the broadcast station currently being received is calculated as (R 115
The frequency division ratio N of the broadcasting station having the same PI code (stored in the AM 43) is stored in place of the frequency division ratio N, and the signal S35 indicating the reception level is also stored in the RAM 4 instead of the previous signal S35.
3 is stored. Then, thereafter, the process proceeds to step 11
Proceed to 8.

If it is determined in step 116 that the reception level of the broadcast station stored in the RAM 43 is higher than the reception level of the currently receiving broadcast station, the process skips steps 116 to 117. Proceed to step 118.

Therefore, according to steps 116 and 117, when a broadcast station broadcasting the same program as the broadcast station already stored in the RAM 43 is received, the stored broadcast station is newly added to the broadcast station. The frequency division ratio N of the broadcast station having a high reception level among the received broadcast stations is the RAM.
43, and the reception level detection signal S35 is stored in the RAM 43. That is, the RAM 43
When the broadcast station of the same program is received,
It is updated to the frequency division ratio N of the broadcasting station having the higher reception level.

Further, in step 112, when the reception level of the received broadcasting station is lower than the specified value, the processing proceeds from step 112 to step 118. Also, when the broadcast station received in step 113 is not an RDS station, the process proceeds from step 113 to step 118.

Then, when the process proceeds to step 118,
In this step 118, the frequency division ratio N is incremented by "1", and then in step 119, the frequency division ratio N is increased to the maximum value 23 corresponding to the maximum reception frequency of 108.0 MHz.
It is checked whether 74 has been exceeded, and if not, the process returns from step 119 to step 111.

Therefore, according to steps 111 to 119, the FM broadcast wave band is scanned. When an RDS station is received by this scanning, the received RDS station is used by using a PI code.
It is checked whether an RDS station of the same program as the DS station has already been registered in the RAM 43. As a result of the check in the above section, when the RDS station of the same program has not been registered in the RAM 43 yet, the frequency division ratio N and the reception level of the currently receiving RDS station are newly set to R.
Register in AM43. As a result of the check in the above section, when the RDS station of the same program has already been registered in the RAM 43, the reception level of the registered RDS station and the currently received RDS station
The reception level of the DS station is compared.

As a result of the above comparison, when the reception level of the RDS station registered in the RAM 43 is higher, the frequency division ratio N of the RAM 43 is left as it is.

As a result of the above comparison, when the reception level of the currently receiving RDS station is higher, the RAM 43
Is changed to the frequency division ratio N of the RDS station currently in use. Is performed.

Then, when the processing of the above-mentioned items is executed for the whole area of the FM broadcast wave band, in step 119, the frequency division ratio N exceeds the maximum value 2374.

Then, the process proceeds from step 119 to step 121. In this step 121, the RAM
It is checked whether or not the division ratio N for 30 stations is stored in 43. When the division ratio N for 30 stations is stored, the process proceeds from step 121 to step 123.
If the frequency division ratio N for 30 stations is not stored in the RAM 43 in step 121, the non-stored address is used as dummy data to store, for example, the minimum frequency division ratio N corresponding to the lowest reception frequency of 87.5 MHz. And a character code indicating a blank are written, and then the process proceeds to step 123.

Then, in step 123, RA
The division ratio N and PS data for 30 stations of M43 are
The data are rearranged in the alphabetical order of the broadcast station names indicated by the data (code order of the PS data). Next, in step 124, the rearranged frequency division ratios N and PS data for the 30 stations are transferred to the memory 44. . At this time, the frequency division ratio N and the PS data are written in the memory 44 in the order of pages, and in each page in the order of areas.

After that, the process proceeds to step 125
To terminate the RDS auto preset.

<< Selection of RDS Auto-Preset Station >> To select an RDS auto-preset broadcasting station, use the page key KPG and the selection keys KN0 to KN9.

That is, each time the page key KPG is pressed, the page of the memory 44 is changed from A → B → C → A →
As shown in B →..., The pages are sequentially selected and cyclically selected, and at this time, characters indicating the selected page are displayed on the LCD 61.

Then, when the page in which the division ratio N of the desired broadcasting station is written is selected, the tuning keys KN0 to KN
Tuning key K of N9 corresponding to the desired broadcasting station
Press Ni (i = 0-9). In this case, as shown in FIG. 4, the tuning keys KN0 to KN9 are stored in the frequency table FTBL.
When the key KNi is pressed, the pressed tuning key K of the selected page is pressed.
From the area i designated by Ni, the frequency division ratio N and the PS data written in the area i are read, and the read frequency division ratio N is set in the variable frequency dividing circuit 22 through the port 51. You.

Further, the PS data read from the frequency table FTBL is supplied to the controller 55,
D61 displays the broadcast station name.

Therefore, it is possible to select a broadcasting station that has been RDS auto-preset in the memory 44 by using the page key KPG and the tuning keys KN0 to KN9.

As described above, “tuning by key KUP or key KDW”, “RDS auto preset”,
For example, "selection of RDS auto preset station" can be performed.

Although the PI code is used in step 114 in the above description, PS data can be used.

[0074]

According to the present invention, RDS auto-preset can be performed. In this case, in particular, according to the present invention, the same program is broadcast when the RDS station is stored as described in the above-mentioned items. Since it is checked whether or not the RDS station is already stored, a plurality of RDS stations broadcasting the same program are not redundantly stored.

Therefore, the capacity of the memory 44 can be reduced, and the memory 44 can be used effectively. Furthermore, although the listener pressed another tuning key KNi,
Without the condition that the same program is received,
Usability improves.

When an RDS station broadcasting the same program as an already stored RDS station is received during the RDS auto preset, the RDS station having the highest reception level is stored in the memory 44. An RDS station with good reception conditions such as S / N can be received.

Further, when the RDS stations are stored in the memory 44, the RDS stations are rearranged in the order of the station names and stored in the memory 44. Therefore, when the listener selects a station by using the tuning key KNi, which station is selected. It is easy to understand which RDS station is registered in the key KNi, and this is also convenient.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an example of a receiver according to the present invention.

FIG. 2 is a flowchart showing a part of an example of processing contents in the receiver of FIG. 1;

FIG. 3 is a flowchart showing a part of an example continued from FIG. 2;

FIG. 4 is a diagram showing an example of a data table.

FIG. 5 is a diagram for explaining an outline of the present invention.

[Explanation of symbols]

 Reference Signs List 10 receiving circuit 12 antenna tuning circuit 14 mixer circuit 16 FM demodulation circuit 19 speaker 20 PLL 21 VCO 22 variable frequency dividing circuit 32 demodulation circuit 33 decoder circuit 35 detection circuit 36 A / D converter 40 microcomputer 41 CPU 42 ROM 43 RAM 44 memory 55 display controller 61 display device 100 processing routine KUP to KN9 operation keys

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H03J 5/00-7/28 H04B 1/16 H04H 1/00

Claims (2)

(57) [Claims] At least a program identification code and a broadcasting station
In a broadcast receiver configured to add program ancillary information including character data indicating a name to a main signal for transmission, a reception frequency is determined based on data corresponding to the reception frequency.
A receiving circuit of the synthesizer scheme constant, from the received broadcast wave signal of the receiving circuit, the program additional
A demodulation circuit for demodulating information ; a detection circuit for detecting a reception level of the broadcast wave signal received by the reception circuit; data corresponding to the reception frequency;
Another code, character data indicating the broadcast station name,
A memory for storing the reception level of the broadcast wave signal; and a preset key. When the preset key is operated, the reception frequency of the reception circuit is changed every predetermined frequency step to change the broadcast frequency band. Scan, and the broadcast wave signal received by this scan is added to the program
If the broadcast wave signal has additional information,
Program identification code or broadcasting station included in additional information
Character data indicating the name is already stored in the above memory.
Is checked, and the program identification code in the received broadcast wave signal is checked.
Character data indicating the mode or broadcast station name
When it is already stored in memory
The reception level detected by the circuit is stored in this memory.
Program identification code or broadcast station name
If the reception level is higher than the reception level corresponding to the
Indicates the data corresponding to the reception frequency and the broadcast station name
Get character data and use this program identification code
Stored in the memory in association with, after the scan, the received stored in the memory
Characters indicating the data and the broadcasting station name corresponding to the frequency
Character data indicating the broadcast station name.
A receiver arranged in the order of codes and stored in the memory . 2. A receiver according to claim 1, wherein data corresponding to said reception frequency and said broadcast station name are indicated.
Character data is the character indicating the broadcast station name
After sorting the data in code order,
Selected according to the country code included in the
A receiver configured to store in the memory in a selectable state .