JPH07221600A - Radio data system receiver - Google Patents

Abstract

PURPOSE:To obtain an RDS receiver in which it is prevented that plural frequencies of broadcasts whose program contents are the same are stored in a preset channel memory in the process of an automatic scanning memory. CONSTITUTION:A controller 8 stores a PI code detected by an RDS demodulation circuit 6 to a storage circuit 9 together with its frequency when a broadcast having been received in the process of an automatic scanning memory serves an RDS service. When number of stations of the received broadcast program is two or more, the identity of the program content is discriminated by comparing the PI code of said broadcast with the PI code of the broadcast station having been already stored in the storage circuit 9 and storage of plural frequencies of the same program content of the broadcast into the preset channel memory is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio data system (hereinafter abbreviated as RDS) receiver capable of receiving radio data system (Radio Data System) broadcasting.

[0002]

2. Description of the Related Art In recent years, RDS broadcasting has been carried out in Europe, in which a subcarrier of 57 kHz is provided for FM broadcasting, and channel selection information and information about program contents are multiplexed and broadcast by a receiver. It provides various services such as demodulating the data of and using it for tuning operation.

The RDS data is 104 as shown in FIG.
It is composed of groups of bits. One group consists of four blocks, one block is 26 bits, 16 bits of which are information words, and the remaining 10 bits are check words. RDS data is transmitted without interruption in group units, and signals indicating boundaries between groups or blocks are not inserted. For this reason, the start point of the group or block is identified by using the offset word added to the check word.

0 to 1 for the information group of RDS data
There are 16 kinds of group types of 5 and one group type is divided into two kinds of versions A and B, respectively. For example, the group type 0A is the frequency list (AF) code of the same network station and the program service name (P
It is used for sending the code of S). PI (Progr
The am Identification (program identification) code is a code for identifying the program as shown in FIG. 3, and is composed of 16-bit data including a code representing a country name, a program, etc., and is always inserted in the block 1. Therefore, it is included in all of the above 16 types of groups and the transmission frequency is about 11 times per second.

On the other hand, in the receiver, an automatic scan memory function capable of sequentially scanning the receivable frequency range and automatically storing the frequencies at which the broadcast can be received in a plurality of preset channel memories, and thereafter ,
It has become popular to have a preset channel memory tuning function that allows the user to specify the memory number etc. and recall the frequency stored in the preset channel memory by the auto scan memory function to perform tuning operation. There is.

[0006]

However, in the case where there are a plurality of broadcasting stations forming a network that broadcasts the same program content, the broadcasting frequency is used in an area located near the boundary between the service areas of the broadcasting stations. It is possible to receive multiple stations with different but same program contents, and if the auto scan memory function described above is executed, the number of broadcasts exceeding the number of preset channel memories provided in the receiver may be received and the same broadcast may be received. A large number of broadcast frequencies of program contents are stored in the preset channel memory, and as a result, there is a problem in that the broadcast frequency originally desired by the user is not stored.

In view of the above conventional problems, the present invention provides an RDS receiver capable of preventing a plurality of broadcast frequencies having the same program content from being stored in a preset channel memory during the execution process of the auto scan memory. It was made for the purpose of doing.

[0008]

In order to solve the above problems, an RDS receiver of the present invention sequentially scans a receivable frequency range, and stores frequencies at which broadcasts can be received in a storage unit having a plurality of preset channel memories. An auto scan memory function that can be automatically stored in sequence, and then the user specifies the memory number etc. and recalls the frequency stored in the storage section with the preset channel memory by the auto scan memory function. The preset channel memory channel selection function that can perform the channel selection operation, the RDS demodulation circuit that demodulates the radio data system signal of the radio data system broadcast, and the broadcast that can be received during the execution process of the auto scan memory function is the radio data system. If you are providing a radio data system The program identification code of is stored in the storage unit together with its frequency, and if the received broadcast is stored for the second or more stations, the program identification code of the broadcast and the broadcast stored in the storage unit having the preset channel memory are stored. Compared with the program identification code, if the frequency of the broadcasting station broadcasting the same program is already stored even if the frequencies having the same program identification code are different, the frequency of the broadcasting station has a preset channel memory. It is characterized by comprising a control device for preventing storage in the storage section.

Further, the receivable frequency range is sequentially scanned,
An auto scan memory function that can automatically store the frequencies that broadcasts can be received in a storage unit that has a plurality of preset channel memories, and then the user can specify the memory number, etc. A preset channel memory tuning function capable of recalling a frequency stored in a storage unit having a preset channel memory by a function to perform a tuning operation, a reception signal detecting means for detecting a reception signal strength at the time of reception, and a radio An RDS demodulation circuit for demodulating a radio data system signal of a data system broadcast, and a program identification code of the radio data system signal when the broadcast received during the execution process of the auto scan memory function provides the radio data system service. Frequency and received signal strength detector Stored in the storage unit together with the received signal strength detected by, and if the received broadcast is stored for the second or more stations, the broadcast program stored in the storage unit that has the program identification code and preset channel memory Control for comparing with the program identification code, and if they have the same program identification code, comparing the received signal strengths of both, and storing the frequency of the broadcasting station with the larger received signal strength in the storage unit having the preset channel memory. It is characterized by having a device.

[0010]

According to the present invention, the program identification code of the radio data system signal together with its frequency is provided when the broadcast received by the control device in the course of executing the auto scan memory function provides the radio data system service. When the storage of the broadcast received and stored in the storage unit is the second or more station, the program identification code of the broadcast is compared with the program identification code of the broadcast stored in the storage unit having the preset channel memory until then, If the frequency of the broadcasting station broadcasting the same program is already stored even if the frequencies having the same program identification code are different, it is prevented that the frequency of the broadcasting station is stored in the storage unit having the preset channel memory. Therefore, the broadcast frequency of the same program content is stored in the preset channel memory. Without being stored multiple duplicate, As a result, the frequency of the broadcast nature user by the over capacity of the storage unit is desired is that disadvantage is eliminated in that not stored.

Further, the control device uses the program identification code of the radio data system signal as the frequency and the received signal strength detection means when the broadcast received during the execution of the auto scan memory function provides the radio data system service. Stored in the storage unit together with the received signal strength detected by, and if the received broadcast is stored for the second or more stations, the broadcast program stored in the storage unit that has the program identification code and preset channel memory To compare with the program identification code, and if they have the same program identification code, compare the received signal strengths of both, and store the frequency of the broadcasting station with the larger received signal strength in the storage unit that has the preset channel memory. , The same program content is released to the area where the auto scan memory function is executed. Only broadcasters good frequency the highest received state even broadcasting stations there more to broadcast are those that can be stored in the storage unit without overlapping programs.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the RDS receiver of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of an RDS receiver in one embodiment of the present invention. In FIG. 1, an FM broadcast wave received by an antenna 1 is a PLL circuit 3 controlled by a controller 8. The frequency is selected by the FM tuner 2 and detected. Then, the obtained multiplexed signal is input to the MPX demodulation circuit 4, and if the received broadcast is stereo, stereo reproduction is performed on the L channel and the R channel, and the audio signal is output via the audio circuit 5.

On the other hand, the multiplexed signal obtained by the FM tuner 2 is also input to the RDS demodulation circuit 6 to reproduce the clock and data of the RDS signal. These are input to the control unit 8 via the RDS synchronization / error detection / correction circuit 7, converted into RDS data or converted into a form which makes it easy for the control unit 8 to realize various services of RDS broadcasting and stored in the storage unit 9. Remembered.

Storage contents such as frequencies of the preset channel memory are stored in the storage device 9. The storage device 9 is usually composed of a RAM or the like, but may be included in the control device 8 when a microcomputer is used for the control device 8. The operating device 10 is used for a tuning operation of the receiver and the like, and the display device 11 is used for the receiving frequency, the receiving condition or the RD.
The various messages of the S service are displayed.

When the user gives an instruction to execute the auto scan memory function from the operating device 10, the control device 8 sequentially scans the receiving frequencies in ascending or descending order from the lower or upper limit of the receiving frequency range. The frequency at which the broadcast can be received is stored in the storage device 9 having a preset channel memory. At this time, the control device 8 also stores the PI code of the broadcast in the storage device 9 when the broadcast provides the RDS service. At the same time, the control device 8 compares the PI code of the broadcast with the broadcast PI code stored in the storage device 9 having the preset channel memory up to that time, if the storage of the broadcast is the second or more station, and if the same. When a broadcast having a PI code is stored, the storage of the broadcast is prevented in order to prevent the frequencies of the broadcast stations having the same program content from being stored in the preset channel memory even if the broadcast frequencies are different. Control not to operate.

As described above, according to this embodiment, the same P
By not storing the broadcast frequency having the I code, it is possible to prevent a plurality of broadcast frequencies having the same program content from being stored.

Next, a second embodiment will be described. The second embodiment is also constructed by the block diagram shown in FIG. However, in this embodiment, the FM tuner 2 is provided with a built-in detection means for the received signal strength so that the control device 8 can read it. As a specific configuration example, there is a method in which the FM tuner 2 outputs the received signal strength in the form of a DC voltage and the control device 8 is provided with an A / D converter or the like to read the signal strength.

In the second embodiment, the control device 8 receives the broadcast received in the process of executing the auto scan memory function as R.
When the DS service is provided, the received signal strength is also stored in the storage device 9 together with the PI code. Next, the control device 8 compares the PI code of the broadcast with the PI code of the broadcast stored in the storage device 9 having the preset channel memory so far when the storage of the broadcast is the second or more station, and the PI code is compared. If the two coincide with each other, the received signal intensities are compared with each other, and the stored content of the preset channel memory is controlled to be updated at a frequency having a higher frequency.

As described above, according to this embodiment, it is possible to store in the preset channel memory the frequency that is considered to be the best in the reception condition for broadcasting the same program content in the area where the auto scan memory is executed. It is possible to provide a person with comfortable tuning operation. This is an effective and appropriate embodiment especially in a case where a stationary receiver used at home does not show a great change in received signal strength each time.

[0021]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, in the RDS receiver, when the broadcast received by the control device during the execution process of the auto scan memory function provides the radio data system service, The program identification code is stored in the storage unit together with its frequency, and if the received broadcast is stored for the second or more stations, the program identification code of the broadcast and the broadcast program stored in the storage unit having the preset channel memory up to that time. If the frequency of the broadcasting station that broadcasts the same program is already stored even if the frequencies having the same program identification code are different, the frequency of the broadcasting station is stored in the preset channel memory. The frequency of the broadcast of the same program content is preset to prevent Since a large number of duplicate channels are not stored in the channel memory, and as a result, the inconvenience that the broadcast frequency originally desired by the user is not stored due to the capacity of the storage section being over, is eliminated. Can be effectively utilized,
It is possible to provide the user with a comfortable tuning operation.

Also, the control device uses the program identification code of the radio data system signal as the frequency and the received signal strength detecting means when the broadcast received during the execution process of the auto scan memory function provides the radio data system service. Stored in the storage unit together with the received signal strength detected by, and if the received broadcast is stored for the second or more stations, the broadcast program stored in the storage unit that has the program identification code and preset channel memory To compare with the program identification code, and if they have the same program identification code, compare the received signal strengths of both, and store the frequency of the broadcasting station with the larger received signal strength in the storage unit that has the preset channel memory. , The same program content is released to the area where the auto scan memory function is executed. Only broadcasters good frequency the highest received state even broadcasting stations there more to broadcast are those that can be stored in the storage unit without overlapping programs.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an RDS receiver according to an embodiment of the present invention.

FIG. 2 is a format diagram showing a baseband structure of RDS data.

FIG. 3 is a diagram showing an RDS message format.

[Explanation of Codes] 6 RDS Demodulation Circuit 7 RDS Synchronization / Error Detection / Correction Circuit 8 Control Device 9 Storage Device 10 Operating Device

Claims (2)

[Claims] 1. An auto-scan memory function capable of sequentially scanning a receivable frequency range and automatically storing frequencies at which broadcasting can be received in a storage unit having a plurality of preset channel memories, and thereafter, Preset channel memory tuning function that allows the user to specify the memory number etc. and recall the frequency stored in the storage unit having the preset channel memory by the auto scan memory function to perform tuning operation, and radio data An RDS demodulation circuit for demodulating a radio data system signal of a system broadcast, and a program identification code of the radio data system signal when the broadcast received during the execution process of the auto scan memory function provides a radio data system service. It is stored in the memory together with When the storage of the received broadcast is the second or more station, the program identification code of the broadcast is compared with the program identification code of the broadcast stored in the storage unit having the preset channel memory so far, and the same program identification code is provided. Even if the frequency is different, if the frequency of the broadcasting station that broadcasts the same program is already stored,
A radio data system receiver comprising a control device for preventing the frequency of the broadcasting station from being stored in a storage unit having a preset channel memory. 2. An auto scan memory function capable of sequentially scanning a receivable frequency range and automatically storing the frequencies at which a broadcast can be received in a storage unit having a plurality of preset channel memories, and thereafter, Preset channel memory channel selection function that allows the user to specify the memory number etc. and recall the frequency stored in the storage section that has the preset channel memory by the auto scan memory function to select a channel. , A RDS demodulation circuit for demodulating a radio data system signal of a radio data system broadcast, and a broadcast received during the execution process of the auto scan memory function provides a radio data system service. Radio data system signal programming if The identification code is stored in the storage unit together with its frequency and the received signal strength detected by the received signal strength detection means. When the storage of the received broadcast is the second or more station, the program identification code of the broadcast and preset by then The program identification code of the broadcast stored in the storage unit having the channel memory is compared, and if they have the same program identification code, the received signal strengths of both are compared, and the frequency of the broadcasting station with the larger received signal strength is compared. A radio data system receiver comprising a controller for storing in a storage unit having a preset channel memory.