JPH0631782Y2 - Car radio receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (b) Industrial field of use The present invention is a vehicle-mounted radio receiver capable of receiving Radio Data System data and capable of searching an alternative frequency with respect to a frequency being received. Regarding

(B) Problems to be solved by the conventional technology / invention An in-vehicle radio that searches and selects an alternative frequency by using alternative frequency data (hereinafter referred to as AF data) which is reception data of the Radio Data System. Receivers are widespread in the European region.

When selecting an alternative frequency using AF data by method B of the Radio Data System described above, when the vehicle enters the service area of the local station, the reception condition of the radio wave becomes good and the alternative is automatically set. Receive local station on frequency.

However, the local station sometimes broadcasts differently depending on the time zone, and in such a case, it has a drawback that it is impossible to continuously listen to the broadcast being received.

The present invention has been made in view of the above points, and its purpose is to provide a broadcasting station of an alternative frequency when the electric field strength of the broadcasting radio wave being received is equal to or higher than a predetermined level. If it is a station, it is to provide an in-vehicle radio receiver that does not receive this local station.

(C) Means for Solving the Problem FIG. 1 is a functional block diagram of the present invention.

The in-vehicle radio receiver of this invention is a Radio Dat
In a vehicle-mounted radio receiver capable of receiving a System data and capable of searching for an alternative frequency with respect to the frequency being received, is the plurality of alternative frequency data received is alternative frequency data by method B? First identifying means for identifying whether or not, and frequency data for selecting a desired alternative frequency from the plurality of received alternative frequency data when the first identifying means identifies the alternative frequency data by method B The selecting means and the second identifying means for identifying whether or not the frequency selected by the frequency data selecting means is a local station are provided, and the electric field strength of the broadcast radio wave being received is equal to or higher than a predetermined level. Moreover, when the second identifying means identifies that the alternative frequency selected by the frequency data selecting means is the frequency of the local station. The local station is configured to prohibit reception.

(D) Operation The operation of this invention will be described with reference to FIG.

According to this invention, Radio Data System
In the in-vehicle radio receiver capable of receiving the data of m and searching for the alternative frequency with respect to the frequency being received, whether or not the received plurality of alternative frequency data are alternative frequency data by the method B. And a frequency data selection for selecting a desired alternative frequency from the plurality of received alternative frequency data when the first identifying means identifies the alternative frequency data by the method B. Means and second identifying means for identifying whether or not the frequency selected by the frequency data selecting means is a local station, and the electric field strength of the broadcast radio wave being received is equal to or higher than a predetermined level, and When the second identifying means identifies that the alternative frequency selected by the frequency data selecting means is the frequency of the local station, the local Received and then, is prohibited, and does not receive the local station also enters the service area of the electric field strength stronger local station by the movement of the vehicle.

Therefore, there is no possibility that the currently broadcast contents are switched.

(E) Embodiment An embodiment of the in-vehicle radio receiver according to the present invention will be described with reference to FIGS. 1 to 4.

In the figure, 1 is an antenna of an in-vehicle radio receiver capable of receiving Radio Data System (hereinafter, referred to as RDS) data, and 2 is a high frequency amplification unit for amplifying the radio wave received by the antenna 1 and a predetermined intermediate frequency. A front end having a mixer section for conversion, 3 is a PLL circuit that functions as a local oscillator of the front end 2, and 4
Is an intermediate frequency amplification circuit including a detection circuit, 5 is a volume regulator for adjusting the level of the detection output of the intermediate frequency amplification circuit 4, 6 is an audio amplifier section, 7 is provided between the volume regulator 5 and the audio amplifier section 6. A muting circuit, 8 is a receiving sensitivity detecting means for detecting the state of the radio wave received from the intermediate frequency amplifying circuit 4, and 9 is an RDS data demodulating means for demodulating RDS data from the output of the intermediate frequency amplifying circuit 4. , 10 is a microcomputer for controlling the in-vehicle radio receiver, 11 is a RAM for storing the received alternative frequency data (AF data), 12 is a key input section for giving instructions to the in-vehicle radio receiver, and 13 is It is a display device of a reception frequency.

Further, 14 is a first identifying means for identifying whether or not the received AF data is alternative frequency data by the method B,
Reference numeral 15 is frequency data selecting means for selecting a desired alternative frequency from a plurality of AF data received when the first identifying means 14 identifies the AF data by the method B,
Reference numeral 16 is a second discriminating means for discriminating whether or not the frequency is local based on the magnitude relation between the frequency selected by the frequency data selecting means 15 and the frequency being received.

The second identifying means 16 is a local station as follows.
Distinguish between non-local stations.

The frequency being received is stored in the address A of the RAM 11, and the alternative frequency data corresponding to the frequency being received is stored in the address B of the RAM 11.

If the data at address A is 100 MHz and the data at address B is 101 MHz as shown in FIG. 3 (a), the frequency at address B is higher than the frequency at address A, so the alternative frequency is Judge as the frequency of a station (non-local station) with the same broadcast content.

Conversely, if the data at address A is 103 MHz and the data at address B is 102 MHz as shown in FIG. 3 (b), the frequency at address B is lower than the frequency at address A, so the alternative frequency Is the frequency of the local station.

In the vehicle-mounted radio receiver configured as described above, the microcomputer 10 uses a PLL based on the output data of the reception sensitivity detection means 8 and the AF data of the RAM 11 generated based on the output data of the RDS data demodulation means 9. The oscillation frequency of the voltage controlled oscillator (VCO) of the circuit 3 is changed to perform the search operation of the broadcasting station, and the mute circuit 7 is operated during the search so as to prevent the audio amplifier section 6 from generating noise. .

Next, the operation of this invention will be described with reference to the flowchart of FIG.

When the plurality of received AF data are alternative frequency data by the method B, the alternative frequency data for the frequency being received is selected from the plurality of received AF data (step S1).

The selected alternative frequency data is the third with respect to the reception frequency.
If the relationship is as shown in FIG. 6B, this alternative frequency data is a local station (step S2), so this alternative frequency data is transferred to a predetermined address in the RAM 11 (step S2).
3).

At this time, if the electric field strength is equal to or higher than a predetermined level (step S4A), the frequency being received is continuously received (step S5).

If the selected alternative frequency data has a relationship with the received frequency as shown in FIG. 3 (a), this alternative frequency data is a non-local station (step S2). Transfer to the specified address.
(Step S4) Then, at this time, if the electric field strength is equal to or higher than a predetermined level and is stronger than the electric wave being received (Step S4A), this non-local station is searched and selected. (Step S5).

Of course, if the electric field strength is below a certain level, the local station,
Channels are selected by a predetermined search regardless of non-local stations (step S6).

In this embodiment, if the electric field strength is above a predetermined level, the local station is not automatically selected.
May be provided with a switch, and the switch may be configured to instruct whether to enable or disable the selection of the local station.

Thus, the in-vehicle radio receiver of the present invention is
In an on-vehicle radio receiver capable of receiving io Data System data and capable of searching for an alternative frequency with respect to the frequency being received, the plurality of alternative frequency data received are alternative frequency data by method B. First identifying means for identifying whether or not the desired alternative frequency is selected from the plurality of received alternative frequency data when the first identifying means identifies the alternative frequency data by Mesoned B. The frequency data selecting means and the second identifying means for identifying whether or not the frequency selected by the frequency data selecting means is a local station are provided, and the electric field strength of the broadcast radio wave being received is equal to or higher than a predetermined level. Moreover, the second identifying means determines that the alternative frequency selected by the frequency data selecting means is the frequency of the local station. When you separate those configured so as to prohibit the reception of the local station.

(F) Effect of the invention Since the vehicle-mounted radio receiver according to the invention is configured as described above, the local station is not received even if the vehicle moves and enters the service area of the local station with strong electric field strength. .

Therefore, the contents of the broadcast station being listened to do not change.

Moreover, it has excellent features such as a simple structure and easy implementation because it can be constructed at low cost.

[Brief description of drawings]

1 to 4 show an embodiment of an in-vehicle radio receiver according to the present invention, FIG. 1 is a functional block diagram, FIG. 2 is a hardware block diagram, and FIG. 3 is an alternative frequency on a RAM. FIG. 4 is a flowchart showing a main part of a microcomputer for controlling the in-vehicle radio receiver, showing the state of data. Explanation of main symbols 2: Front end 3: PLL circuit 7: Muting circuit 8: Reception sensitivity detecting means 9: RDS data demodulating means 10: Microcomputer 14: First identifying means 15: Frequency data selecting means 16: First Identification means of 2

Claims (1)

[Scope of utility model registration request] 1. In a vehicle-mounted radio receiver capable of receiving Radio Data System data and capable of searching for an alternative frequency with respect to a frequency being received, a plurality of alternative frequency data received are determined by a method B. First identifying means for identifying whether or not it is the alternative frequency data, and a desired alternative from the plurality of received alternative frequency data when the first identifying means identifies the alternative frequency data by the method B. A frequency data selecting means for selecting a frequency and a second identifying means for identifying whether or not the frequency selected by the frequency data selecting means is a local station are provided, and the electric field strength of the broadcast radio wave being received is predetermined. At a level equal to or higher than the predetermined level and the alternative frequency selected by the frequency data selecting means is the frequency of the local station. When the identification means has identified vehicle radio receiver, characterized by being configured so as to prohibit the reception of the local station.