JP3158138B2 - Radio receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention relates to release data multiplexing of radio
Relates radio receiver capable of receiving broadcasts from systems broadcasting station transmission, which is also configured to search to the broadcast receiving traffic information broadcast station that broadcasts traffic information more Radio
And a radio receiver compatible with the data multiplex broadcasting system.

[0002]

2. Description of the Related Art A signal to which information for realizing various functions is added together with a normal audio signal (this added information is referred to as R
2. Description of the Related Art A radio data system for broadcasting DS data) is known. As RDS data, for example, traffic information and adjacent network stations (broadcast stations of the same series, such as NHK-FM Tokyo, NHK-FM Kofu, N
HK-FM Shizuoka, etc.). That is, in addition to the audio signal, the RDS broadcast station is a list of broadcast frequencies of network stations adjacent to the periphery of the service area of the broadcast station, that is, a PI indicating that it is the same network station as an alternative frequency list called an AF list. A program identification code called a code is transmitted. Therefore, the PI code is used to identify that the broadcasting frequency is the same as the broadcasting frequency of the network station of the receiving broadcasting station but the network is different from the broadcasting station.

Further, when the broadcasting station is a traffic information broadcasting station, information called TP data indicating that the broadcasting station is a traffic information broadcasting station, and when traffic information is being broadcast, TA indicating that traffic information broadcasting is being performed. Information called data is also transmitted.

A conventional radio receiver that can also receive RDS data, that is, an RDS-compatible radio receiver (hereinafter referred to as RD)
(A radio receiver corresponding to S is simply referred to as a radio receiver.) In an RDS broadcast reception, an AF list and a PI code broadcast from a broadcasting station currently being received are stored in a storage device provided in the radio receiver. .

[0005] When the radio receiver is mounted on a vehicle and moving, for example, the electric field strength due to the received radio wave drops below a predetermined value as a result of the movement and away from the service area of the broadcasting station currently receiving. When the radio receiver detects, the radio receiver automatically refers to the stored AF list and automatically adjusts the reception frequency to receive a broadcast from a broadcast station having a frequency in the AF list and a PI code matching the broadcast station. When the broadcast is not received from the broadcast stations of all the frequencies in the AF list, it is possible to search for the broadcast station of the same PI code by referring to the PI code so that the reception can be continued. Has been. As a result, the broadcast reception of the same network station can be continued even while moving.

On the other hand, when it is desired to receive a traffic information broadcast by a radio receiver, a broadcast station of a frequency in the AF list is stored in a storage device by pressing, for example, a traffic information reception instruction key switch provided on the radio receiver. And the frequency list of the broadcasting station that is a traffic information broadcasting station
The code is stored to receive a traffic information broadcast periodically broadcast. In addition, when TP data is stored in the storage device in addition to the AF list and the PI code, and the user wants to receive the traffic information broadcast by the radio receiver, for example, the user presses a traffic information reception instruction key switch provided on the radio receiver. A with TP data
A broadcast station in the F list is searched to receive a regularly broadcasted traffic information broadcast.

In the conventional radio receiver configured as described above, the traffic information reception instruction key switch is pressed,
In addition, when a long distance travel is performed while instructing reception of RDS data and listening to traffic information broadcasting, the broadcasting is basically the same as the broadcasting station which is a traffic information broadcasting station and is currently receiving. The reception frequency is automatically switched one after another to the broadcast reception of the network station, and the user can listen to the traffic information broadcast when the traffic information is being broadcast while continuously receiving the broadcast of the network station.

[0008]

However, in a conventional radio receiver, when the user is traveling a long distance while listening to a traffic information broadcast, the electric field intensity of the currently received broadcast wave falls below a predetermined value. Then, the receiving broadcast station is automatically switched to another traffic information broadcast station to receive the traffic information broadcast. As a result of this switching, a new receiving broadcasting station that has been switched may be an irrelevant broadcasting station that is not the network station and the network station that was just received. In this state, the contents of the AF list recorded in the storage device are updated to the AF list of the broadcast station that has been switched and the broadcast station that is the network station.

However, when the vehicle is traveling for a long distance, the electric field strength of the radio wave of the receiving broadcasting station temporarily drops below a predetermined value due to, for example, passage through a tunnel or multipath interference. Also, when the electric field strength of all the broadcasting stations in the AF list temporarily drops below a predetermined value, even if the cause of the electric field strength reduction is resolved and the electric field strength of the radio wave of the receiving broadcasting station recovers, Since the contents of the AF list have been updated to the AF list of a broadcast station that is not a network station as shown in the above, the broadcast of the receiving broadcast station, that is, the broadcast station that was received immediately before the contents of the AF list were updated There was a problem that the content could not be heard continuously.

[0010] It is an object of the present invention to provide a radio receiver capable of continuously receiving the immediately preceding broadcast content by selection even when instructing to receive a traffic information broadcast.

[0011]

A radio receiver according to the present invention searches for a receivable traffic information broadcasting station when it becomes difficult to receive a broadcast from a traffic information broadcasting station that also broadcasts traffic information. In a radio receiver compatible with a data multiplex broadcasting system of a radio configured to shift to broadcast reception of a traffic information broadcasting station, an electric field intensity detecting means for detecting that the electric field intensity of a received radio wave has dropped to a predetermined value or less, Receiving broadcasting station priority indicating means and electric field strength of receiving broadcasting station
When the frequency has dropped, the alternative frequency
The next station with the same PI code
The operation of switching to the broadcast reception of the broadcast station in the
Repeatedly every time the electric field strength decreases,
Switch reception for all broadcast stations listed on the
As a result, the electric field strength of the received
If it is less than or equal to the predetermined value and the receiving station priority
The first broadcast in the alternative frequency list
Receiving station switching control means for switching to broadcast reception of a station.

[0012]

The radio receiver according to the present invention is receiving radio signals .
When the electric field strength of a broadcasting station is reduced,
A broadcasting station listed on the frequency list and PI
Switch to broadcast reception of the next station in the same order
Operation is repeated every time the electric field strength of the broadcasting station decreases.
All stations on the alternative frequency list.
As a result of switching the reception
If the electric field strength of the received radio wave is less than
Alternate frequency when transmission priority instruction is given
Switching to broadcast reception of the first broadcast station in the list.
Therefore, never alternative frequency list to an alternative frequency list in this case the other network station is updated, alternative
Switch to broadcast reception of the first station in the frequency list
Thus, the broadcast received immediately before can be continuously received.
Conversely, when it is desired to receive the traffic broadcast information with priority, the receiving broadcast station priority instruction may be canceled, and either one can be selected by the broadcast receiver.

[0013]

The present invention will be described below with reference to examples. FIG.
FIG. 1 is a block diagram showing a configuration of an embodiment of a radio receiver according to the present invention.

The radio receiver 20 of this embodiment includes a front end 1, an intermediate frequency amplifier 2 for amplifying an intermediate frequency signal output from the front end 1, a detector 3 for detecting the output of the intermediate frequency amplifier 2, Stereo demodulation circuit 4, stereo demodulation circuit 4 for receiving the detection output and performing stereo demodulation
A volume control circuit 5 for controlling the output level of the vehicle, wherein the volume control circuit 5 is capable of controlling the volume to a predetermined value when outputting traffic information under the control of the system controller 12 described below; A mute circuit 6 for muting the adjusted audio signal, an audio signal amplifying circuit 7 for amplifying the output of the mute circuit 6, and a speaker 8 driven by the output of the audio signal amplifying circuit 7 are provided to perform a receiving operation.

The radio receiver 20 further includes a frequency synthesizer 9 constituting a local oscillator, an electric field intensity detection circuit 10 for detecting an electric field intensity from the intermediate frequency amplifier circuit 2, and an RDS demodulation circuit for demodulating RDS data from the detection output. 11
And a system controller 12 for controlling the radio receiver 20.

The key switch group 14 is an RDS instruction key switch 1 for instructing to operate as an RDS compatible receiver.
4-1. It includes a traffic information reception instruction key switch 14-2 for instructing reception of traffic information, and a reception station priority instruction key switch 14-3 for instructing to prioritize broadcast reception of the current reception broadcast station. .

The system controller 12 comprises a microcomputer cooperating with the RAM 13 and receives the output signal of the electric field strength detection circuit 10, the demodulated output from the RDS demodulation circuit and the output of the key switch group 14 to constitute the frequency synthesizer 9. The frequency division ratio data is output to the variable frequency divider of the PLL circuit to control the reception frequency, the volume of the volume control circuit 5 is controlled when outputting traffic information, and a mute control signal is sent to the mute circuit 6. Make mute function.

The system controller 12 is functionally
Alternative frequency list storage control circuit 12-1 for controlling storage and updating of alternative frequency list in RAM 13, RAM
13, an AF list search circuit 12-2 that scans the alternative frequency list stored in the
I code match detection circuit 12-3, traffic information broadcasting station detection circuit 12-4 for detecting TP code, reception state deterioration determination circuit 12-5 for determining deterioration of reception state, and reception giving priority to reception of the current reception broadcasting station Station switching control circuit 12-6
It has.

Here, the electric field strength detection circuit 10 and the reception state discrimination circuit 12-5 correspond to the electric field strength detection means, and the receiving station priority indication key switch 14-3 corresponds to the reception broadcasting station priority indication means. , Receiving station switching control circuit 1
2-6 corresponds to the receiving station switching control means.

The radio receiver 20 configured as described above
Will be described based on the flowchart shown in FIG.

Receiving instruction, RDS reception instruction key switch 14-1 and traffic broadcast reception instruction key switch 1
When 4-2 is pressed, by cooperation with the alternative frequency list storage control circuit 12-1, the PI code match detection circuit 12-3, and the traffic information broadcasting station detection circuit 12-4,
A broadcast from a desired broadcast station is received, and a frequency list of a broadcast station in the AF list in the RDS data transmitted from the broadcast station, which is a traffic information broadcast station, and has the same PI code is It is stored in the RAM 13 together with the PI code as an alternative frequency list. Therefore, the RAM 13
The broadcast station based on the alternative frequency list stored in the above is a traffic information broadcast station that also broadcasts traffic information and is the same network station, and when the traffic information is broadcast from a receiving broadcast station, the traffic information is received. (Step S0).

In the state of step S0, the electric field intensity of the receiving broadcasting station is detected by the electric field intensity detecting circuit 10, and it is judged by the receiving state judging circuit 12-5 whether or not the detected electric field intensity has fallen below a predetermined value. (Step S1). If it is determined in step S1 that the electric field strength has dropped below the predetermined value, the search is performed under the control of the AF list search circuit 12-2, and the first frequency in the alternative frequency list is read out. The frequency division ratio corresponding to the output frequency is supplied to the frequency synthesizer 9 and switched to broadcast reception of a broadcast station of the frequency (step S2).

Here, the noise is detected together with the detected electric field strength, and it is also detected that the noise has become equal to or more than a predetermined value. Step S2 may be executed when one of them is determined by making a determination that the above has occurred.

After step S2, it is checked whether or not the electric field strength is equal to or more than a predetermined value (step S3). When the electric field strength is judged to be equal to or more than the predetermined value, the PI code coincidence is detected by the PI code coincidence detecting circuit 12-3. Is checked (step S4), and if it is determined that the PI codes match, the receiving broadcast station is determined to be the broadcasting station of the frequency at that time, and is replaced with the alternative frequency list of the determined receiving broadcasting station. The frequency list is updated (step S5), and the process is executed again from step S1.

If it is determined in step S3 that the electric field strength is not equal to or more than the predetermined value, or if it is determined in step S4 that the PI codes do not match, after step S3 or step S4, the alternative frequency list is displayed. Is read, and the frequency division ratio corresponding to the read frequency is supplied to the frequency synthesizer 9 to switch to the broadcast reception of the broadcast station of the frequency (step S6).

After step S6, it is checked whether or not the receiving station switching operation has been performed for all the frequencies in the alternative frequency list (step S7). Is executed again from step S3 following step S7.

Therefore, the electric field intensity of the radio wave of the receiving broadcasting station decreases to a predetermined value or less, and the steps S1 to S7
Step S3 is performed, and during this time, if it is determined that the electric field strength is equal to or higher than the predetermined value, the same network station as the receiving broadcast station that was receiving in Step S0, and the electric field strength is equal to or higher than the predetermined value. The reception frequency is switched to the traffic information broadcasting station.

If it is determined in step S7 that the receiving station switching operation has been performed for all the frequencies in the alternative frequency list, the first frequency in the alternative frequency list is read, and the frequency corresponding to the read frequency is read. The frequency division ratio is supplied to the frequency synthesizer 9 to switch to the broadcast reception of the broadcast station of the frequency (step S8), and a predetermined value corresponding to the time counted by the timer counter is set (step S9).

After step S9, it is checked whether or not the electric field strength is equal to or higher than a predetermined value (step S10). If it is determined in step S10 that the electric field strength is not equal to or more than the predetermined value, step S10
Then, the elapse of a predetermined period is waited (step S11), the count value of the timer counter is incremented (step S12), and it is checked whether the count value of the timer counter has reached the predetermined value (step S13). Is not reached, the process is executed again from step S10.

Therefore, if the electric field strength recovers to the predetermined value or more within the period set in step S9, if the receiving station is the same network station as the receiving broadcast station in step S8, and the electric field strength is higher than the predetermined value. The reception frequency is switched to the traffic information broadcasting station.

When it is determined in step S13 that the count value of the timer counter has reached the predetermined value, that is, in each reception for all frequencies in the alternative frequency list, the electric field strength does not recover to the predetermined value. When the electric field strength does not recover to the predetermined value even after waiting for the predetermined period in the reception of the first frequency in the alternative frequency list,
It is checked whether or not the receiving station priority instruction key switch 14-3 has been pressed (step S14).

If it is determined in step S14 that the receiving station priority instruction key switch 14-4 has been pressed, the process is executed again from step S1 following step S14. Therefore, for example, when the electric field strength of the radio wave of the receiving broadcasting station drops below a predetermined value while passing through the tunnel and the electric field strength is not recovered even by receiving all the frequencies in the alternative frequency list, the tunnel after passing through the tunnel In many cases, the electric field strength of the radio wave of the broadcasting station received immediately before the passage is restored, and in such a case, the receiving station priority indication key switch 14-4 is pressed down to give priority to the reception of the traffic information and the tunnel. The broadcast of the receiving broadcast station immediately before entering the tunnel or the reception of the network station of the receiving broadcast station immediately before entering the tunnel is continued.

If it is determined in step S14 that the receiving station priority instruction key switch 14-4 has not been pressed, a search operation for a traffic information broadcasting station is performed following step S14. Therefore, in this case, a new traffic information broadcasting station is searched, and it may not be possible to receive the broadcast of the network station of the broadcasting station that has been received immediately before. it can.

In the radio receiver of the above-described embodiment, the alternative frequency list is the same as the broadcasting station in the AF list in the RDS data transmitted from the receiving broadcasting station and the traffic information broadcasting station. Although the case where the frequency list of the broadcasting station of the PI code is used is exemplified, the frequency of the broadcasting station in the AF list in the RDS data transmitted from the receiving broadcasting station and having the same PI code is replaced with the alternative frequency. When the traffic information reception instruction key switch 14-2 is pressed, whether or not it is a traffic information broadcast station is added as a list, and information on whether or not the station is a traffic information broadcast station is added to each frequency of the alternative frequency list. It is sufficient to refer to the information as to whether or not the broadcast station is a traffic information broadcast station and has a frequency in the alternative frequency list.

Also, when the present invention is applied to the EON function in the RDS, the information indicating that the station is a traffic information broadcasting station is not stored in the RAM 13, and the traffic information is transmitted only when the receiving station priority is not instructed in step S14. This can be dealt with by shifting to the traffic information broadcasting station being broadcast only during the traffic information broadcasting period.

[0036]

As described above, according to the radio receiver of the present invention, the electric field strength of the receiving broadcasting station is low.
When the radio station is dropped, the
Stations in the following order with the same PI code
The operation of switching to the broadcast reception of the broadcast station is the electric field of the broadcast station.
Each time the intensity decreases, the process is repeated sequentially, and the alternative frequency
Switch reception for all broadcast stations listed on the
As a result, the electric field strength of the received
If it is less than or equal to the predetermined value and the receiving station priority
The first broadcast in the alternative frequency list
Switching to broadcast reception of the station. Therefore, this place
The alternative frequency in the alternative frequency list of the other network station.
The list is not updated and the alternative frequency list
Switch to broadcast reception of the first broadcast station and receive immediately before
There is an effect that the broadcast that has been performed can be continuously received .

When it is desired to preferentially receive the traffic information broadcast, it is sufficient to cancel the reception broadcast station priority instruction, and there is an effect that either one can be selected by the broadcast receiver.

[Brief description of the drawings]

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

FIG. 2 is a flowchart for explaining the operation of an embodiment of the radio receiver according to the present invention.

[Explanation of symbols]

 Reference Signs List 10 electric field strength detection circuit 11 RDS demodulation circuit 12 system controller 13 memory 14 key switch group 12-1 alternative frequency list storage control circuit 12-2 AF list search circuit 12-3 PI code match detection circuit 12-4 traffic information broadcasting station detection Circuit 12-5 Reception condition deterioration determination circuit 12-6 Reception station switching control circuit 14-1 RDS reception instruction key switch 14-2 Traffic information reception instruction key switch 14-3 Reception station priority instruction key switch

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H03J 7/18 H03J 5/02 H04B 1/16

Claims (1)

(57) [Claims] When a broadcast reception from a traffic information broadcasting station that also broadcasts traffic information becomes difficult, a receivable traffic information broadcasting station is searched for, and a transition is made to broadcast reception of the searched traffic information broadcasting station. An electric field intensity detecting means for detecting that the electric field intensity of the received radio wave has fallen below a predetermined value, a receiving broadcast station priority instructing means, and a receiving broadcast. When the station's electric field strength decreases, the broadcast
Stations listed on the alternative frequency list that includes the station
Of the next station with the same PI code
The operation to switch to the signal is changed every time the electric field strength of the broadcasting station decreases.
Repeat in order, all broadcast stations on the alternative frequency list
As a result of switching the reception for all
The electric field strength of the received radio wave is less than a predetermined value,
When the receiving station priority instruction is given,
Switch to broadcast reception of the first station in the frequency list
And a receiving station switching control means.