JP2928717B2 - 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, and more particularly to a radio receiver effective for use in a data multiplex broadcasting system (RDS, etc.).

[0002]

2. Description of the Related Art In Europe, an RDS (Radio Data System) has been put to practical use for providing various services to vehicle drivers by digitally multiplexing tuning data and program identification data into FM radio broadcast signals. Yes,
It is expected to spread worldwide in the future. Typical RDS services include a PI (program identification) service for identifying a country, a reception area, and a program name of a broadcast station, and a PS (reception station name display) service for displaying a received broadcast station name on a tuner display. There are an AF (similar program broadcast frequency list) service for displaying other broadcast station frequencies broadcasting the same program, a TP service for identifying a broadcast station of traffic information, and the like.

[0003] The AF service is provided with a search function for receiving another broadcasting station radio wave of the same program broadcast when the received electric field strength of the RDS radio wave transmitted from the broadcasting station by the in-vehicle tuner falls below a certain level. ing. This search is performed based on the AF list transmitted from the broadcast station stored in the memory in advance.

[0004] For example, when the radio wave intensity from a certain broadcasting station becomes weak while driving in an automobile, the AF received in the reception area concerned becomes weak.
Other stations transmitting the same broadcast content are automatically received based on the list. At that time, the AF list stored in the vehicle-mounted memory is updated to the AF list received in the area.

[0005]

As described above, the AF service processing of the conventional RDS radio receiver is executed.
However, the conventional RDS radio receiver has the following problems. For example, when the AF list transmitted from the station A has the frequency of the station B among the broadcasting stations A and B, the AF list transmitted from the station B does not have the frequency of the station A Is assumed. When the broadcast station received by the vehicle by traveling changes from station A to station B, when the vehicle is located at the boundary, etc., the relative strength of the received radio wave intensity of station A and station B is Since the station is unstable and does not always move to the station B, the frequency of the station A that does not originally exist in the AF list of the station A is forcibly entered into the AF list, and then the operation shifts to the operation of selecting the station B. I do. By doing so, the reception of the station A can be continued even if the station does not shift to the station B after all. Next, when station B is selected, B
Since the frequency of the station A does not exist in the AF list of the station, the frequency of the station A is deleted by updating the AF list. Then, at the next transition from station B to station A, since the frequency of station A is not in the AF list, a frequency search over the entire frequency range is performed, and for example, the target station broadcast is performed by referring to the PI information. It must be received and no quick service is available. Further, this problem occurs every time the station A moves back and forth between the stations A and B, and cannot be overlooked in reality.

An object of the present invention is to provide a radio receiver which can obtain a more effective alternative frequency service without erasing the frequency before the transition.

[0007]

In order to solve the above-mentioned problems, a radio receiver according to the present invention receives a data multiplex broadcasting system and stores, in a memory, alternative frequency list data included in the data of the data multiplex broadcasting system. It has an alternative frequency search function of storing as an alternative frequency list and automatically switching to a station having a good reception condition based on the alternative frequency list, and starting the alternative frequency search in response to a decrease in received radio field intensity. A radio receiver that updates the alternative frequency list after receiving the searched station,
At the time of the alternative frequency search, the frequency received before the search is stored in the memory as priority alternative frequency data, and at the time of updating the alternative frequency list, frequency data other than the priority alternative frequency data is updated. It consists of.

[0008]

According to the present invention, in the radio receiver, at the time of the alternative frequency search, the frequency received before the search is stored in the memory as priority alternative frequency data, and the priority alternative frequency data is not updated when the alternative frequency list is updated. I have to.

[0009]

Next, embodiments of the present invention will be described with reference to the drawings. FIGS. 1A and 1B are flowcharts showing the operation processing procedure of the radio receiver according to the present invention. FIG. 2 is a configuration block diagram of a radio receiver for realizing the present embodiment. In this embodiment, an RDS receiver is used as an example of a radio receiver.

First, the configuration of a radio receiver according to the present embodiment will be described with reference to FIG. 2. A received signal received by an antenna 1 is converted by a front end 2 into an IF signal. The front end 2 incorporates a voltage controlled oscillator (VCO) and a mixer, and sets a reception frequency based on a control signal from the microcomputer 9 in cooperation with the PLL circuit 3. The converted IF signal is detected by an IF detection circuit (IF / DET) 4 and then a volume circuit 5
Is used to adjust the volume.

The output of the IF detection circuit 4 is detected by a reception sensitivity detection circuit 7 as the reception sensitivity, for example, as an electric field strength, and sent to a microcomputer 9. The RDS data demodulation circuit 8 demodulates the detection signal from the IF detection circuit 4 and sends out the obtained RDS data to the microcomputer 9.

The microcomputer 9 receives the sensitivity signal from the reception sensitivity detection circuit 7 and the RDS data from the RDS data demodulation circuit 8 and performs the above-mentioned RDS service.
The RAM 10 is a memory for storing an AF list included in the received RDS data.
To read and update.

The mute circuit 6 performs a mute process on the audio signal from the volume circuit 5 under the control of the microcomputer 9. The audio signal that has passed through the mute circuit 6 is output from the speaker 12 after being amplified by the output amplifier 11.

In this embodiment, processing such as writing and updating of the AF list is performed by the microcomputer 9, and the processing procedure will be described below with reference to FIG.

In the AF search shift processing, as shown in FIG. 1A, the frequency before the shift is stored in the RAM 10 as the priority AF.

In the AF updating process, as shown in FIG. 1B, first, after AF data is input, it is determined whether or not the input AF data is a condition for updating (step). S1). Here, if the update condition, RAM
It is determined whether or not the AF data stored in No. 10 is stored as priority AF data (step S
2). In steps S1 and S2, if it is not the update condition or if it is stored as the priority AF data, the process is terminated. If it is not stored as the priority AF data in step S2, the AF data stored in the RAM 10 is deleted (step S3).

[0017]

As described above, according to the radio receiver of the present invention, the frequency before the shift to the alternative frequency search is stored as priority alternative frequency data, and this priority alternative frequency data is updated when the alternative frequency list is updated. As a result, a smoother alternative frequency search can be performed.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an operation processing procedure of an embodiment of a radio receiver according to the present invention.

FIG. 2 is a configuration block diagram of a radio receiver for realizing the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Antenna 2 Front end 3 PLL circuit 4 IF detection circuit 5 Volume circuit 6 Mute circuit 7 Reception sensitivity detection circuit 8 RDS data demodulation circuit 9 Microcomputer 10 RAM 11 Output amplifier 12 Speaker

Claims (1)

(57) [Claims] (1)Receiving the data multiplex broadcasting system,
Frequency list included in the data of the data multiplex broadcasting system
Data is stored in a memory as an alternative frequency list, and
Automatic transmission to stations with good reception conditions based on the alternative frequency list
It has an alternative frequency search function that switches
Initiate the alternative frequency search in response to a decrease in electrolytic strength
After receiving the searched station, the alternative frequency list is
In the radio receiver to be updated, At the time of the alternative frequency search, the frequency received before the search
The wave number is stored in the memory as priority alternative frequency data.
When updating the alternative frequency list, the priority alternative
Updating frequency data other than frequency data
like A radio receiver characterized by being constituted.