JP3279379B2 - Radio receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio receiver for information multiplex broadcasting, and more particularly to a radio receiver capable of updating the same program broadcasting station of a different program network preset with a preset key.

[0002]

2. Description of the Related Art In a car radio, when a vehicle moves out of a service area during reception of a certain station, the station automatically selects a new station performing the same broadcast, or transmits a traffic information broadcast. It is convenient to be able to automatically switch from another source to radio broadcasting, etc., at the start of the program. For this reason, ARI (Automatic Radio Information) systems are adopted in West Germany, Australia, Switzerland, etc., to broadcast traffic information at appropriate times and
The M broadcast signal is superimposed with identification code data indicating that the current receiving station is a traffic information broadcasting station or identification code data indicating that the current reception station is broadcasting a traffic information, and traffic information can be easily written using these identification code data. I am listening.

[0003] By the way, when a car moves long distances and goes out of the service area of the receiving station, it is necessary to reselect the station every time. For this reason, in addition to being able to easily obtain traffic information, there has been a demand for a sophisticated channel selection function. This demand is particularly strong in Europe, where FM broadcasts with relatively narrow service areas are the main radio broadcast services and car radio broadcast reception rates are high. Therefore, the RDS (Radio Data System) has been proposed by the European Broadcasting Union to meet this demand and is being put to practical use.

[0004] The RDS is a system in which various digital data are superimposed on an FM radio broadcast signal. As a message, (1) a program identification code (PI) of a currently received FM broadcast, and (2) a broadcast station name ( (3) Broadcasting station frequency list (AF) during broadcasting of the same program (4) Program content identification code (PTY) (5) Transmission state identification code (DI) (6) Identification code of music or conversation (M / S) and (7) Identification code (TP) of traffic information broadcasting station (8) Identification code (TA) during traffic information broadcasting. The above (1) to (6) are information related to the channel selection function, and (7) and (8) are traffic information.

As described above, in the RDS, the FM
Since a message related to broadcasting, traffic information, and the like are transmitted in a multiplex manner, a special channel selecting operation and a traffic information receiving operation, which have never been achieved before, can be performed using the message.

For example, a broadcast station frequency list (AF list) and a program (broadcast program) identification code (PI code) during the same program are demodulated, and the reception electric field strength of the current receiving station is set based on the data. When the level falls below the level, the reception station strength is sequentially tuned to each of the AF stations on the AF list to check the reception field strength (referred to as AF search).
It is determined whether the PI code of the F station matches the original receiving station. If the PI code matches, the AF station is received. If the PI code does not match, the AF station having the next highest received electric field strength is received. It can be carried out.

In countries such as the United Kingdom and Sweden, EON (Enhanced Other Network)
k) is transmitted in a data structure of type 14A, and PI, A related to a program network other than the program network of the broadcast being received.
It has information such as F, TP, and TA. Therefore, by using the EON information, it is possible to easily select a broadcasting station of another network.

FIGS. 2 and 3 each show an example of an RDS data format transmitted by being superimposed on an FM broadcast signal. FIG. 2 shows a type 0A group for transmitting RDS data related to the program network of the FM broadcast signal itself. Of the four blocks, the first block has PI (TN), the second block has a group address, and the TP. (TN), PTY (TN), TA
(TN), two AF (TN) in the third block, the fourth
Two characters of PS (TN) are sent in the block. (T
N) indicates that it is related to the FM broadcast program network.

FIG. 3 shows a type 14A for transmitting RDS data relating to another program network different from the FM broadcast signal. Of the four blocks, the first block is PI (TN) and the second block is PI (TN). Is the group address, TP (TN), PTY (TN), T
P (EON), information address, PS (EON) for two characters in the third block, and two AF (EO
N), a tuning frequency (TN) and a mapped FM frequency (EON) or a mapped LF /
MF frequency (EON), PTY (EON) and TA (EO
N), etc., information corresponding to the information address, PI (EO) in the fourth block
N) is sent. (EON) indicates that it is related to another program network different from FM signal broadcasting. Therefore, AF (EON) and mapped FM frequency (EO
By using channel selection data such as N) or PI (EON), it is possible to switch the receiving station to another desired program network.

That is, in a conventional RDS receiver having a preset key, in the radio (FM reception) mode using the EON information, for example, the preset key 1 is used.
In the case where broadcast stations having different PIs (different program networks) are preset in the stations 2 and 3, respectively, the preset key 1 is a broadcast station broadcasting EON,
Assuming that N information has been obtained, if the reception electric field strength of the broadcasting station of the preset key 1 during reception becomes weak, a broadcasting station broadcasting the same contents in the same network is automatically selected and the preset key 1 E obtained by one broadcast station
Based on the ON information, the preset station frequency (mapped FM frequency) corresponding to each PI of the preset keys 2 and 3 can be automatically updated.

FIG. 4 shows different Ps obtained as EON information.
6 is a mapped FM frequency table showing an example of a mapped FM frequency corresponding to I. Explaining in detail based on the mapped FM frequency table of FIG. 4, for example, when the car is in the area A, the frequencies that can be received in that area are respectively set to the preset key 1 of 92.0 MHz (EON broadcasting station), which is PI1, and the preset key 2 to the preset key 2. 94.0 MH which is PI2
Assume that the preset key 3 is preset to 96.0 MHz, which is PI3. Here, when the car moves from the area A to the area C while receiving 92.0 MHz of the preset key 1, 92.0 MH of the preset key 1 is used.
z is 92.4 MHz (see FIG. 2)
And the tuning frequency in FIG. 3)
To receive.

Therefore, referring to FIG. 4, 92.4 MHz
When the mapped FM frequency of the C area corresponding to is obtained,
The mapped FM frequency corresponding to PI2 is 94.4M
Hz, and the mapped FM frequency corresponding to PI3 is 96.4 MHz. Therefore, the preset key 2 of 94.0 MHz is automatically updated to 94.4 MHz, and the preset key 3 of 96.0 MHz is updated to 96.4 MHz.
Update to z. The RDS receiver performs a receiving operation even in a mode other than the radio mode, for example, in a tape mode. If an RDS station is received and EON information is obtained, the preset is automatically updated. be able to.

[0013]

However, in the conventional RDS radio receiver, in the radio (FM reception) mode, for example, the preset keys 1, 2, and 3 have different Rs with different PIs.
DS stations are preset, and it is assumed that EON information has been obtained. When the reception electric field strength of the RDS station of the preset key 1 during reception becomes weak, a broadcasting station broadcasting the same contents in the same network is automatically set. In addition to being able to select a station, the preset keys 2 and 3 can automatically update preset frequencies (mapped FM frequencies) of broadcast stations corresponding to the respective PIs. Also, when a broadcast station other than the RDS station is being received, when the received electric field strength becomes weak, the station is usually manually reselected, so that there is no sense of incongruity.

However, when a broadcast station other than the RDS station is received and the mode is switched to another mode such as a tape mode, the station is not an RDS station. Cannot be updated, so when switching from the tape mode to the radio mode again, there is a sense of discomfort that the same broadcast cannot be received even if the preset key is pressed.

Therefore, an object of the present invention is to automatically change the frequency of a different broadcasting station of a program network corresponding to each preset key to the frequency of another broadcasting station of each network when switching from another mode to the radio mode. To provide a radio receiver that can be dynamically updated.

[0016]

In order to achieve the above-mentioned object, in a radio receiver for information multiplex broadcasting, a FM broadcast signal is superimposed with predetermined data relating to a program network of the broadcasting station and another network. Broadcasters
Supports multiple preset keys for presetting
A memory , a mode switching unit for switching from the radio mode to another mode, and when the switching unit switches from the radio mode to another mode, the radio mode is operated, and the radio mode is being received in the radio mode. wherein the plurality with the transition from the broadcast station when the broadcast station other than the information multiplex broadcast station to a large information multiplexing station reception field strength, based on predetermined data relating to other programs network obtained from the transition information multiplex broadcasting station of stored in the corresponding memory to the pre <br/> set key, respectively
This is achieved by a preset update unit that can update a multiplex broadcast preset frequency .

[0017]

When the mode is switched from the radio mode to another mode by the mode switching unit, the radio mode is operated, and when the broadcasting station being received in the radio mode is other than the information multiplex broadcasting station, the radio station is switched to the other mode. The plurality of preset keys are shifted to an information multiplex station having a large reception electric field strength and based on predetermined data relating to another program network obtained from the shifted information multiplex broadcast station.
Each multiplex broadcast program stored in the memory corresponding to
The reset frequency can be updated.

[0018]

FIG. 1 is a block diagram of a main part of an RDS (Radio Data System) receiver according to the present invention. FIG. 1 is a main block diagram of an RDS (Radio Data System) receiver according to one embodiment of the present invention. Reference numeral 1 denotes a PLL circuit which outputs a predetermined voltage signal corresponding to a station to be received to the FM front end 2. The FM front end 2 receives a broadcast station input from the antenna ANT based on the voltage signal, and generates a predetermined intermediate frequency signal (IF). 3
Is an intermediate frequency detection amplifier which amplifies the intermediate frequency signal converted by the FM front end 2 to a predetermined level and detects it.

Reference numeral 4 denotes MPX, which is an intermediate frequency detection amplifier 3
Demodulated into a stereo signal. 5
Is a switch that switches between radio and tape sources.
Denotes an amplifier (AMP), which amplifies a stereo signal in accordance with a volume setting value (not shown). Reference numeral 7 denotes a speaker, which is driven by the amplifier 6 and outputs an audio signal. 8
Is an RDS decoder, which demodulates RDS data (AF list, PI data, etc.) transmitted at a predetermined transmission timing. An error detection and correction circuit 9 detects an error of the RDS data demodulated by the RDS decoder 8 while synchronizing each group, and corrects the error.

Reference numeral 10 denotes a signal meter, which monitors the signal strength (for example, electric field strength) by performing DC detection on the intermediate frequency signal output from the intermediate frequency detection amplifier 3 and detects the signal strength of the receiving station. Reference numeral 11 denotes a display unit for displaying a reception frequency and the like. An operation unit 12 includes a radio key 12a for switching to a radio mode, a tape key 12b for switching to a tape mode, and a preset key 12c having six preset keys of numbers 1 to 6. A tape playing unit 13 performs a PLAY operation and a pause operation under the control of a controller described later.

Reference numeral 14 denotes a controller, and the configuration of the controller 14 will be described in detail. First, 14a is RDS
The data (PI, AF, TP, TA, etc.) is stored for each program network, and the frequency of the desired broadcast station and the PI of the program network to which the frequency belongs are stored in the preset key 12c by the preset key 12c of the operation unit 12. A memory for storing corresponding data or storing other data.
The demodulated RDS data is registered in the memory 14a, and when the signal strength of the RDS station is monitored and the AF station is received, the mapped FM frequency for the AF station is obtained. 1
4a is a data registration / update unit for updating the frequency corresponding to the preset PI, and 14c is a system control unit. (1) Monitors the signal meter 10 of the receiving station (RDS station), Is weakened,
An AF search is performed, (2) a preset frequency is called in response to an operation command from the preset key 12c of the operation unit 12, and (3) a radio key 12a of the operation unit 12.
When the mode is switched from the radio mode to the tape mode according to the switching command from the tape key 12b or (4) when the mode is switched from the radio mode to the tape mode, if the EON information is not obtained first, the EON is performed by the seek operation. Receiving a broadcast station that is sending information
(5) If a broadcast station other than the RDS station has been received before switching to the tape mode (5), a broadcast station having the maximum reception electric field strength among the preset RDS stations is firstly selected. If the RDS station is not preset, the RDS station having the maximum signal strength is received by the seek operation.

FIGS. 5 and 6 are flow charts for explaining the operation of the controller 14, and according to the flow charts, the preset update in another mode according to the present invention will be described in detail. In FIG. 5, when the system control unit 14c of the controller 14 receives a command to switch to the radio mode by pressing the radio key 12a of the operation unit 12 (step 1).
01) First, it is determined whether or not the EON information is obtained in the memory 14a (step 102), and if it is obtained, the process proceeds to step 103.

If the EON information has not been obtained in the process of step 102, the process proceeds to step 103, and the EON information of the EON broadcasting station is received by the seek operation (step 1).
03). Thereafter, the process proceeds to step 104 to sequentially receive preset broadcast stations (step 10).
4). Therefore, the system control unit 14b checks the broadcast station stored in the memory 14a in correspondence with the preset key 14c and whether the broadcast station is an RDS station (step 105), and determines whether the RDS station has the maximum signal strength. If there is a broadcast station (step 106), the broadcast station is received (step 107). If there is no broadcast station having the maximum signal strength in the process of step 106, a seek operation is started (step 108), the process returns to step 105, and the same processes are repeated.

Referring now to FIG. 6, the current receiving station (R
The signal strength of the current receiving station is monitored by the signal meter 10 for the purpose of maintaining the signal strength of the DS station) in a good reception state.
09), the system control unit 14c obtains an AF frequency from the AF list stored in the memory 14a, outputs a frequency control signal for each AF station to the PLL circuit 1, and
A search is started (step 110). When the AF station having the maximum signal strength is received (step 111), the signal strength level is compared with the signal strength level of the original receiving station (step 112). If the signal strength level is not higher than the signal strength level of the original receiving station, the signal is returned to the original receiving station (step 111). Step 113). Thereafter, the flow returns to step 109 to repeat the same processing.

On the other hand, if the signal strength level of the received AF station is higher than the signal strength level of the original receiving station in step 112, the data registration unit 14b of the controller 12 sets the RDS decoder 8, the error detection and correction circuit 9 Through A
The RDS data of the AF station, such as the F list and the PI data, is read (step 114), and thereafter, the PI data stored in the memory 14a by the system control unit 14b is checked (step 115), and if the PI data does not match. For example, an AF station having the next highest signal strength is received (step 116), and the process returns to step 112 and repeats the same processing.

If the PI data match in step 115, the system control unit 14b determines reception of the AF station as the current receiving station (step 113). Therefore, the data registration / update unit 14b stores the RDS of the receiving station in the memory 14a.
The data is registered, and the mapped F corresponding to the preset broadcast station PI stored in the memory 14a is registered.
The M frequency is obtained and updated (step 118). Thereafter, the flow returns to step 109 to repeat the same processing.

The present invention relates to an RDS (Radio Data System) containing traffic information data in Europe.
The present invention is applicable not only to a receiver for radio data systems but also to a receiver for radio data systems such as RDBS (Radio Data Broadcasting System) containing traffic information data in the United States.

[0028]

As described above, according to the present invention, the radio mode is operated when the mode is switched from the radio mode to another mode by the mode switching section, and the broadcast station receiving in the radio mode is set to the information multiplex broadcasting. When the station is not a station, the station shifts from the broadcasting station to an information multiplex station having a large reception electric field strength, and corresponds to the plurality of preset keys based on predetermined data on another program network obtained from the shifted information multiplex broadcasting station. Each multiplex broadcast preset frequency stored in the memory can be updated, so it supports multiple preset keys.
These preset frequencies can be updated at once, and the update
This has the effect of shortening the processing time.

[Brief description of the drawings]

FIG. 1 shows an RDS (Radio Data System) according to the present invention.
FIG. 2 is a block diagram of a main part of a receiver for use in the present invention.

FIG. 2 is an explanatory diagram showing an example of an RDS data transmission format.

FIG. 3 is an explanatory diagram showing an example of an RDS data transmission format.

FIG. 4 is a mapped FM frequency table showing an example of a mapped FM frequency corresponding to each PI.

FIG. 5 is a first flowchart for explaining the operation of the controller 14 of FIG. 1;

FIG. 6 is a second flowchart for explaining the operation of the controller 14 in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 PLL circuit 2 FM front end 3 Intermediate frequency detection amplifier 8 RDS decoder 9 Error detection and correction circuit 10 Signal meter 12 Operation unit 12a Radio key 12b Tape key 12c Preset key 14 Controller 14a Memory 14b Data registration / update unit 14c System control unit

Claims (1)

(57) [Claims] 1. An information multiplex broadcasting radio receiver for superimposing predetermined data on a program network of a broadcasting station and another network on an FM broadcasting signal, a plurality of preset keys for presetting a broadcasting station.
A corresponding memory , a mode switching unit for switching from the radio mode to another mode, and operating the radio mode when the mode is switched from the radio mode to another mode by the switching unit. When the broadcasting station in the middle is not an information multiplex broadcasting station, the station shifts from the broadcasting station to an information multiplex station having a large reception electric field strength, and based on predetermined data relating to another program network obtained from the shifted information multiplex broadcasting station. Menus corresponding to the plurality of preset keys
The preset broadcast frequency of each multiplex stored in the memory
A radio receiver, comprising: a preset update unit capable of updating the number .