JPH0683094B2 - Car radio receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention stores frequency data based on an area identification code included in transmission data of a radio broadcasting station such as RDS (Radio Data System), and is receiving the frequency data. The present invention relates to a radio receiver capable of automatically switching a frequency data group that can be called by a preset key from a plurality of frequency data groups stored in advance in a preset memory according to the area.

<Prior art> In a car radio, it is usually the driver who operates it, and when the car moves a long distance and goes out of the service area of the receiving station, it is necessary to re-tune each time. Has been demanded. This requirement was strong especially in Europe where FM broadcasting, which has a relatively small service area, is the main body of radio broadcasting services and the ratio of car radio reception is high. The data system standardized by the European Broadcasting Union to meet this requirement is RD
It is S (Radio Data System).

RDS is a method that multiplexes various data (data that can be used for automatic selection of the best receiving station, traffic information identification, broadcasting station name display, etc.) for FM broadcasting. One of those received data
There is a PI signal. The PI signal is a code for identifying an area, and has a unique code depending on the country and broadcast application range. Therefore, the area can be identified by referring to the PI signal.

<Problems to be Solved by the Invention> By the way, a vehicle-mounted radio receiver with a preset channel selection function, in which the reception point moves with the movement of the vehicle, has a reception point even if it receives the broadcasting station selected by the preset channel. If you move out of the area, you will not be able to receive it, and the frequency data that was preset in the memory will be useless. There was a problem that it had to be fixed.

An object of the present invention is to solve the above-mentioned problems and to automatically detect the area even when the receiving point moves out of the area, and change the area by switching the preset memory contents corresponding to the area so that the contents can be recalled. Is to make it possible to receive a broadcasting station which is always in a good reception state by preset tuning.

<Means for Solving the Problem> According to the present invention, the above-mentioned problem is discriminated by the area identification code discriminating means in the in-vehicle radio receiver having the area discriminating code discriminating means included in the transmission data of the radio broadcasting station. Storage means for storing the frequency data of the station received for each area, preset tuning means for recalling the frequency data stored in the storage means, tuning means for tuning to a station of a predetermined frequency, and station to which the tuning means tunes Of the frequency data stored in the storage means to the tuning means, and detects the maximum level station based on the level obtained from the level detection means. Then, the frequency data stored in the area to which the station of the maximum level belongs can be tuned by the preset channel selection means. It is solved by providing a that controller.

<Operation> The control unit tunes the stations of all the frequency data stored in the storage unit to the tuning unit, detects the maximum level station based on the level obtained from the level detection unit, and then detects the maximum level. The frequency data stored in the area to which the station belongs can be selected by the preset channel selecting means.

<Embodiment> FIG. 1 is a block diagram of an in-vehicle radio receiver showing an embodiment of the present invention.

Reference numerals 1 and 2 are PLL circuits, which output predetermined voltage signals corresponding to the stations to be received to the front ends 5 and 6, respectively. The front ends 5 and 6 each receive a broadcasting station input from the antenna ANT based on the voltage signal and generate a predetermined intermediate frequency signal (IF). An FM detector 3 detects each intermediate frequency signal converted by the front ends 5 and 6. Reference numeral 7 denotes a multiplex demodulation circuit that stereo-demodulates the detection output of the FM detector 3, and the demodulated stereo audio signal is output from the speaker 9 via the amplifier 8.

Reference numeral 10 is a level detector, which monitors the level of the IF signal output from the front end 6 to detect the antenna ANT.
A signal having a level corresponding to the electric field strength of the receiving station, which is input from, is output to the control unit 13.

An RDS decoder 11 demodulates a PI signal or the like sent at a predetermined transmission timing from an output signal of the FM detector 3.

An RDS data error detection unit 12 detects an error in transmission data such as a PI signal while synchronizing with each group and corrects the error. Various types of transmission data including the PI signal output from the RDS decoder 11 are input to the control unit 13 via the RDS data error detection unit 12.

13 is a control unit of a microcomputer configuration, which receives a preset memory 14 for storing frequency data for each area according to a PI signal as an area identification code, and a reception of all frequency data stored in the preset memory 14. It has a comparison unit for comparing a signal according to the electric field strength with a signal according to the received electric field strength of the broadcasting station currently being received. The control unit 13 performs automatic tuning, and also stores the selected broadcasting station in the preset memory 14
Performs control and processing when storing in.

Reference numeral 16 denotes an operation / display unit, which is a display 17 for displaying a frequency, and an up / down display for increasing or decreasing the reception frequency.
Down key 18, automatic tuning key for automatic tuning of broadcasting stations 1
9. It has a preset key 20 for storing and recalling the frequency data of the selected broadcasting station in the preset memory 14.

The operation of FIG. 1 will be described below.

When the automatic tuning key 19 is pressed in the existing area, the control unit 13 automatically changes the tuning frequency of the front end 5 together with the PLL circuit 1 to perform automatic tuning control, and displays the tuning frequency on the display 17. When any one of the preset keys 20 to be stored next is pressed, the frequency data of the automatically selected broadcasting station is stored in a predetermined address of the preset memory 14. The address of the memory for storing the frequency data is selected by determining the PI code sent during reception by the control unit 13, and the frequency data is stored at the address set in advance corresponding to the PI code. Remembered.

FIG. 2 shows a setting example of the memory. In the figure, the preset memory 14 can store up to 6 stations in _one area. For example, the memory addresses are M1 to M6 for the A ₁ area, M7 to M12 for the A ₂ area, and so on. Set M6n _{-5 to} M6n for the An area.

Up to six pieces of frequency data receivable in one area are stored in each address of the preset memory 14 set in the above procedure. However, the number that can be stored in one area is not limited to six, and can be arbitrarily set like the number of preset keys.

Further, frequency data which can be received by moving to different areas and receiving up to 6 data each time is stored in a predetermined address of the preset memory 14.

FIG. 3 is a diagram showing a virtual reception area. Now
At the point in the area A shown in FIG. 3, when one key of the preset key 20 is pressed to select the preset channel, the RDS decoder 11 outputs the PI signal indicating that the area is the area A from the output from the FM detector 3. Is input to the control unit 13. The control unit 13 selects the frequency data stored in advance in the corresponding address of the preset memory 14 in correspondence with the input PI code and the pressed preset key 20.

Further, the control unit 13 changes the tuning frequency of the front end 6 using the PLL circuit 2 constantly or at predetermined time intervals,
All frequencies stored in advance in the preset memory 14 are received and obtained through the level detector 10,
The comparison unit 15 compares each signal corresponding to the received electric field strength with respect to all the frequency data stored in the preset memory 14.
And the frequency data stored in the six memory addresses for the area to which the frequency data having the largest received electric field strength belongs is selected by the preset key 20. In this way, the area being received is discriminated and the frequency data corresponding to the discriminated area can be selected by the preset key.

Therefore, the receiving point moves to the point shown in FIG. 3, and the receiving electric field strength for the frequency data of the memory address corresponding to the B area is more than that for the frequency data of the memory address corresponding to the A area. If the larger one is detected, the contents of the preset memory 14 are B
Even if the preset key is pressed by pressing the preset key 20 at the point after the switching to the contents corresponding to the area, the optimum reception state can be immediately obtained. still,
The same effect can be expected with the same operation when the points 'and' are reached.

In the above embodiment, the writing and calling to the memory by the preset key 20 are distinguished from each other by pressing the preset key 20 for a predetermined time or longer as writing and pressing the preset key 20 for a predetermined time or less as a call.

Also, the broadcasting of the preset memory is not limited to the preset memory manually operated by the user in the broadcasting area,
Automatic preset memory may be performed by operating the auto memory key.

<Effects of the Invention> As described above, according to the present invention, the frequency data for each area is stored in the preset memory according to the area identification code, and the area being received is discriminated. Since the data can be tuned by the preset channel selection means, the preset memory can be automatically switched according to the change of the receiving point, which has an excellent advantage that the troublesome operation can be eliminated.

[Brief description of drawings]

FIG. 1 is a block diagram of an on-vehicle radio receiver showing an embodiment of the present invention, FIG. 2 is a diagram showing an example of setting a preset memory, and FIG. 3 is a diagram showing a virtual reception area. 11 …… RDS decoder 12 …… Error detector 13 …… Control unit 14 …… Preset memory 20 …… Preset key

Claims (1)

[Claims] 1. A vehicle-mounted radio receiver having area identification code discrimination means included in transmission data of a radio broadcasting station, and storage means for storing frequency data received for each area discriminated by the area identification code discrimination means. Preset tuning means for calling the frequency data stored in the storage means, tuning means for tuning to a station having a predetermined frequency, level detection means for detecting the level of the station tuned by the tuning means, and the tuning means The stations of all the frequency data stored in the storage means are tuned, the station of the maximum level is detected based on the level obtained from the level detection means, and the station is stored in the area to which the station of the maximum level belongs. A vehicle-mounted radio equipped with a control unit that enables frequency data to be tuned by the preset tuning unit. Receiver.