JPH0576206B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] In Germany and other countries, a traffic information system called the ARI system is used, which multiplexes specific subcarriers onto FM broadcast radio waves and broadcasts them, in order to identify the traffic information FM station that broadcasts traffic information. Data broadcasting of information is being carried out. Since the frequency of traffic information FM stations differs depending on the region, this ARI system receiver scans the FM broadcast radio waves to identify this specific subcarrier and automatically selects the traffic information FM station. However, since scanning starts from the frequency of the last FM broadcast station received, or from the first frequency, it takes time to select the traffic information FM station. As a result, you may miss traffic information. Focusing on the fact that the last traffic information FM station received has a high probability of being selected as the traffic information FM station again, the frequency of the last traffic information FM station received is memorized and scanning starts from this frequency. This reduces the time required for channel selection.

[Industrial application field]

The present invention is based on ARI (Autofahrer Rundfunk), a traffic information system used in Germany and other countries.
Regarding receivers for the Information System) system,
In particular, it relates to a receiver that shortens the automatic tuning time for FM stations that broadcast traffic information.

[Conventional technology]

In addition to audio and video broadcasts, data broadcasts that transmit information in the form of codes and data are being carried out. In Germany, FM stations that broadcast traffic information are placed in each region, and in order to identify the FM stations,
In a system called the ARI system, 57kHz subcarriers are constantly multiplexed on the radio waves of FM stations that broadcast traffic information (referred to as traffic information FM stations in the following explanation), making them identifiable. This traffic information FM station does not always broadcast traffic information, but usually broadcasts programs such as music, and broadcasts traffic information for about 5 minutes every hour. This subcarrier is modulated at a specific frequency in order to distinguish that traffic information is being broadcast and the target area.
Figure 4 shows the basic form of the ARI method.

As shown in FIG. 4, in the FM broadcast receiver having the ARI function, the program signal receiving section 12b processes normal audio broadcasting, and the program signal receiving section 8b decodes the identification and modulation of the subcarrier, thereby providing traffic information. It is possible to identify that it is an FM station and to identify the start of broadcasting traffic information. Therefore, with this type of receiver, the traffic information FM stations that can be received change depending on movement between regions, so when the ARI function is activated, the FM broadcast radio waves are scanned to identify whether the above subcarrier exists, and the subcarrier is I always select broadcasting stations that emit radio waves that have radio waves. Therefore, if the FM radio switch is turned on and the ARI function is also operating, traffic information will be displayed.
If the FM station is selected and traffic information is not being broadcast, normal music programs etc. will be broadcast. Once the traffic information broadcast starts, you can listen to the traffic information as it is.

If the FM radio is not turned on,
When the ARI function is in operation, the part that performs the ARI function is powered on and operating, and similarly selects the traffic information FM station and monitors the start of traffic information broadcasting. There is. Then, when the traffic information broadcast starts, the FM radio is activated to broadcast the traffic information, and when the traffic information broadcast ends, the FM radio operation is stopped again. Therefore, if you turn on this switch for ARI, even if you are listening to a cassette tape, when the traffic information broadcast starts, it will automatically switch to the FM radio traffic information broadcast, so you will never miss the traffic information. There is an advantage.

[Problem to be solved by the invention]

If you keep the ARI function running, you will not miss any traffic information, but you will not be able to listen to other FM stations while the ARI function is running.
If you want to listen to a station, you need to turn off the ARI switch to stop operation. Also, if you want to listen to the cassette tape or don't need traffic information, you will have to turn off the ARI switch.

Once the ARI switch is turned off, when the ARI switch is turned on again, the FM broadcast radio waves are scanned and the traffic information FM station is automatically selected as described above, but with conventional receivers, the last FM broadcast is The frequency of the broadcast station you listened to is stored, and many devices start scanning from that frequency. Others scan from the beginning of the FM band. Therefore, the frequency at which scanning starts has nothing to do with the frequency of the traffic information FM station, and even if you turn on the ARI switch and start operation, it takes a considerable amount of time to select the traffic information FM station. , if traffic information is being broadcast, the user will miss the broadcast. In that case, traffic information cannot be obtained until the next broadcast, which is a problem.

The present invention has been made in view of the above problems, and the traffic information FM is
The purpose is to prevent people from missing traffic information by reducing the time it takes to select a station as much as possible.

[Means to solve the problem]

In order to shorten the tuning time of the traffic information FM station, the present invention focuses on the fact that the same traffic information FM station is selected as long as the driver is driving in the same area, and uses the frequency of the traffic information FM station that was previously received. By memorizing this frequency and starting scanning from this frequency, the probability of hitting a traffic information FM station immediately after scanning starts is increased and the time required for channel selection is shortened. FIG. 1 is a diagram showing the basic configuration of an ARI receiver according to the present invention. In other figures, the same functional parts are represented by the same numbers with lowercase letters.

The one shown in Figure 1 is a traffic information FM station that broadcasts traffic information by multiplexing specific subcarriers onto FM broadcast radio waves.
This is a receiver for the ARI system. Reference numeral 1 denotes automatic tuning means, which scans FM broadcast waves to identify the above-mentioned subcarriers and automatically selects a traffic information FM station. 2
is a frequency storage means that stores the broadcast frequency of the traffic information FM station and updates the broadcast frequency every time the traffic information FM station is selected. The automatic channel selection means 1 is characterized in that it shortens the time required to select a traffic information FM station by starting scanning from the broadcast frequency stored in the frequency storage means 2.

[Effect]

In the ARI-based traffic information system, traffic information FM stations that broadcast traffic information are set up for each region, and the radio waves from these broadcast stations are multiplexed with specific subcarriers and broadcast. is made identifiable. Traffic information FM stations vary depending on the region, so when the ARI system receiver becomes unable to receive traffic information FM stations while driving, it scans FM broadcast waves to search for traffic information FM stations. An automatic channel selection means 1 is provided for selecting a new traffic information FM station so that it can be received. When reactivating the ARI function, it is also necessary to select the traffic information FM station.

FM radio stores the frequency of the last broadcast station it received, and when the FM radio is restarted, it will listen to the last station it received again. When selecting a traffic information FM station,
Scanning is performed from the frequency of the last received station, or from the beginning of the FM band. Therefore, there is no relationship between the traffic information FM station and the scanning start frequency, and it takes a considerable amount of time to select a station. Therefore, if you are driving in the same area, the target traffic information FM station is the same, so if you memorize the frequency of this station and start scanning from this frequency, the probability of hitting the traffic information FM station first is very high. Therefore, the time required for channel selection can be shortened. When driving long distances, the receivable traffic information FM stations naturally change, so the stored frequency is updated each time a traffic information FM station is selected.

〔Example〕

In an ARI system receiver, it is appropriate to use a microcomputer (hereinafter referred to as a microcomputer) to perform scanning processing and storage for selecting a traffic information FM station. The configuration of a certain receiver is shown in FIG.

In FIG. 2, reference numeral 3a denotes a detector, in which only a specific frequency is extracted, and the FM signal, which is a normal program signal, is amplified by an amplifier 4a, and is output as audio from a speaker 5a. 6a is a microcomputer. 7a is a PLL circuit, which determines the frequency extracted by the detector 3a based on the output from the microcomputer 6a. 8a is a subcarrier analysis unit that detects a 57kHz subcarrier multiplexed with the radio waves of the traffic information FM station, and analyzes whether traffic information is being broadcast or not.
The signal indicating the presence of this subcarrier is called an SK signal, and the signal indicating that traffic information is being broadcast is called a DK signal, both of which are output to the microcomputer 6a. The above features are the same as existing ARI receivers.

Reference numeral 2a denotes a frequency memory that stores the reception frequency output to the PLL circuit 7a according to instructions from the microcomputer 6a when the traffic information FM station is received. The frequency is rewritten every time a traffic information FM station is selected.

3 is a flowchart showing the operation of automatically selecting and automatically receiving a traffic information FM station by the microcomputer 6a in the receiver of FIG. 2. In step 101, it is determined whether the ARI activation switch 9a is turned on. Step 101 is repeated until this switch is turned on. When the ARI start switch 9a is turned on here, in step 102, the frequency of the last received traffic information FM station stored in the frequency memory 2a is read out, and this frequency is output to the PLL circuit 7a for channel selection. . Next, in step 103, the subcarrier analyzer 8
Read the SK signal and DK signal from a. In step 104, the existence of the SK signal, that is, the traffic information FM
It is determined whether the station is a station or not. As long as you drive in the same area, you will receive the same traffic information FM station, so there is a high possibility that you will receive the traffic information FM station the first time.
If the traffic information FM station cannot be received, the frequency is changed in step 105 and steps 103 to 105 are repeated until the traffic information FM station is received.

When the traffic information FM station is selected in this way, the frequency of the traffic information FM station is stored in the frequency memory 2a in step 106. Then in step 107
Determine whether a DK signal exists, that is, whether traffic information is being broadcast. If the radio is not being broadcast, it is determined whether the radio is operating or not. If it is not on the air, jump to step 113 regardless of whether the radio is operating or not. If traffic information is being broadcast, it is determined in step 108 whether the radio is operating, and if it is not operating, the radio is turned on in step 109. This allows you to hear traffic information. In step 110, it is determined whether a DK signal exists, that is, whether traffic information is being broadcast, and step 110 is continued until the end of the broadcast.

When the traffic information broadcast ends, in step 110 it is determined whether the radio switch is on. If it is on, you are listening to a radio broadcast, so the traffic information broadcasting station program will continue to be output. If you have not turned on the radio, there is no need for radio broadcasting after the traffic information broadcast ends, so you can proceed with the steps.
Turn off the radio with 112.

In step 113, it is determined whether the ARI start switch 9a is on, and as long as it is on, the step continues.
Return to step 103 and repeat the operations up to step 113.

The frequency memory 2a needs to maintain the stored frequency even after the ARI activation switch 9a is turned off. Generally, in car radios, even if the radio switch and the ARI switch are turned off, part of the power remains on, so the frequency memory 2a does not need to be non-volatile, but all It needs to be a rewritable non-volatile memory such as EEPROM when the power is turned off.

〔Effect of the invention〕

As explained above, when activating the ARI function to select a traffic information FM station, there is a high probability that the traffic information FM station will be received at the beginning of scanning, so the time required for tuning can be shortened, and traffic information Reduces missed listening.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the basic configuration of an ARI receiver according to the present invention, and FIG. 2 is a diagram showing the configuration of an embodiment of an ARI receiver using a microcomputer for control. FIG. 3 is a flowchart showing the automatic channel selection and automatic reception operations of the ARI system receiver of FIG. 2, and FIG. 4 is a diagram showing the basic form of the ARI system, which is data broadcasting. In the figure, 1... Automatic tuning means, 2... Frequency storage means, 3... Detection means, 4... Amplification means,
5... Speaker, 6a... Microcomputer, 7a...
PLL circuit, 8a...Subcarrier analysis section, 9a...
ARI activation switch.

Claims (1)

[Scope of Claims] 1. A receiver for the ARI system that makes it possible to identify a traffic information FM station that broadcasts traffic information by multiplexing a specific subcarrier on FM broadcast radio waves, which transmits FM broadcast radio waves. scanning to identify the subcarrier;
automatic tuning means 1 for automatically selecting the traffic information FM station; and a frequency storage for storing the broadcast frequency of the traffic information FM station and updating the broadcast frequency each time the traffic information FM station is selected. means 2, said automatic channel selection means 1;
An ARI system receiver characterized in that the time required to select a traffic information FM station is shortened by starting scanning from the broadcast frequency stored in the frequency storage means 2.