JPS6013619B2 - Radio receiver for traffic information broadcasting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises an automatic tuner, a station code decoder, a message code decoder, a received level analyzer, and a control circuit controlled by said decoder and said analyzer, The control circuit relates to a radio receiver for traffic information broadcasting, which interrupts the channel selection operation and energizes the audio reproduction device only when a traffic information broadcasting station worthy of reception is received while transmitting traffic information.

In the traffic information broadcasting system operated in the Federal Republic of Germany, transparent very high frequency (VHF) radio programs identify a particular station as a traffic information broadcasting station and also identify when traffic information is about to be transmitted. The program contains various inaudible code signals indicating .

The so-called station signal is the third harmonic of the stereo pilot frequency of 1 Hz, or a frequency of 57 KHz modulated onto the actual VHF transmit frequency. The so-called message signal is amplitude modulated onto this station signal frequency at a frequency of 125 Hz. The station signal is also modulated on this, 20HZ and 55H
It has a region signal with one of six frequencies between Z. (For example Fu skin schau 14th lid, 1
97 Puoh July 5th, pages 535-538 or W
irlessWmld Volume 79, May 1973, 2
(See Soichi page 240). Relatively high frequency 57K
Hz station signals, depending on the transmission strength in question and the type of circuitry used, can be analyzed very quickly and provide information as to whether the station just received is one that provides regular traffic information. can be obtained after 100 microseconds. After this analysis, the next available information is the message signal, which requires approximately 50 milliseconds to analyze. The most time-consuming part is the analysis of region signals. Special radio receivers for this traffic information broadcast system are already known. Such receivers are equipped with decoders for station signals, message signals and region signals, and with these receivers it is possible to select the desired traffic information broadcast station. It is also known to perform analysis of station, message and region signals in conjunction with automatic tuners. Furthermore, in such known receivers for traffic information broadcasting with automatic tuning,
Tuning is interrupted when a traffic information broadcasting station with a station signal and a message signal is received at a preset maximum reception level through a control circuit that depends on the station signal and message signal and also on the reception level from the station. It is also known that automatic tuning is controlled so that traffic information broadcasting can be performed by just
2311). The reception level is measured by comparing it with a fixedly set reference reception level. Therefore, depending on the setting of the level reference value, all traffic information broadcasting stations exceeding this minimum reception level are analyzed by the tuner. If the level reference value is relatively small, in a region where there are a large number of traffic information broadcast stations, a large number of broadcast stations will be analyzed, and users will be overwhelmed by the large number of traffic information broadcasts. However, since each traffic information broadcast station must be analyzed not only for the station signal, but also for the message signal, and perhaps even for the region signal, it takes a relatively long time to tune the whole thing. It takes. Therefore, the time taken for the entire tuning is longer than the time between the start of the message signal from the traffic information station and the start of the actual traffic information broadcast, which usually follows the acoustic station's callsign tone (signature tune). can also be quite long. ``By the time this station is found by the tuner, the important part of the traffic information broadcast has already finished and the user will therefore only get the information that has been given away. If this is the case, the reception level reference value may be increased so that only a few traffic information broadcasting stations with relatively high reception levels can be received.
However, in other reception areas, this adjustment may result in too few traffic information broadcasting stations being checked, and important broadcasting stations not being received at all. Another drawback of this known traffic broadcast radio receiver is that when a traffic broadcast station is found that has only a relatively low reception level, and therefore can be faintly picked up, the station that can be better received is within the range of the tuner. This means that the synchronized action will stop even if it is within the range. Note that, in the current mobile radio system in Japan, a system is not used in which a traffic information broadcasting station is distinguished from other broadcasting stations. It is therefore an object of the present invention to develop and improve a radio receiver of this kind for traffic information broadcasting, in which these drawbacks are avoided and traffic information broadcasts from selected traffic information broadcasting stations can be clearly received. It is to do as you please.

This object is achieved by a radio receiver for traffic information broadcasting according to the claims.

Further similar developments are represented by the dependent claims. According to the present invention, the number of transmitting stations worth receiving is based on the number of traffic information broadcasting stations received during each tuning period.
Since the level reference value is controlled, a sufficiently small number of traffic information broadcasting stations are automatically selected and analyzed at all times, and the entire tuning takes only, for example, 0.5 seconds, i.e. the beginning of the message signal and the actual traffic information broadcasting. It is certainly done within a shorter period of time than the period between.

For many German traffic information broadcasters, this period is usually 2 seconds and the call sign fee is sent. Due to this,
Not only will the actual information content not be erroneous, but the user will be able to open at least a portion of the call sign sound and broadcast station display announcement. Example B.
The invention will be described in more detail below with the aid of the drawings, which represent schematic diagrams. FIG. 1 shows a basic circuit diagram of an automobile radio receiver for traffic information broadcasting according to the present invention.

It comprises a conventional heterodyne receiver 1 with a corresponding intermediate frequency stage, tunable by an automatic tuner 2 with diode tuning. The audio frequency output from the receiving section 1 is passed through a switch 3 to a low frequency amplifier 4 and then to a loudspeaker 5 and further to a built-in station signal decoder 6 and message code decoder 7. In the illustrated embodiment, a second additional receiving channel 8 is provided, in which the low frequency output can also be switched via the switch 3 to the low frequency amplifier 4 and the loudspeaker 5. This additional receiving channel 8 is only needed if the car radio listener wishes to listen to other programs during the traffic information broadcast. The outputs from the message signal decoder 7 and the station code decoder 6 are controlled by a control circuit 20 so as to stop automatic channel selection only when the traffic information broadcasting station that just starts broadcasting traffic information is received by the receiver 1. The automatic tuner 2 is controlled through the automatic tuner 2. For this purpose, the outputs from these decoders 6 and 7 are combined, for example, in an AND gate 9 through which the start/stop inputs of the automatic tuner 2 are correspondingly controlled. When the automatic tuner 2 is tuned to the correspondingly selected traffic information broadcasting station, the switch 3 is simultaneously switched through the message signal decoder 7, and the flexible frequency output of the receiver 1 is connected to the speaker 5. . If no traffic information broadcast is received, switch 3 remains in the other position and the program from receiving channel 8 is routed to speaker 5. Furthermore, a reception level measuring device, which is a bell comparator 10 in this embodiment, which compares the high frequency input level at the receiving section 1 with a bell reference value P, is also provided.

This can most conveniently be done by comparing the automatic gain control voltage R of the receiver 1 with a correspondingly adjustable reference voltage. By measuring the level, the number of traffic information stations to be analyzed during tuning is automatically limited, so that the overall tuning is performed relatively quickly. Limiting the number of broadcast stations is achieved in the illustrated embodiment by automatically controlling the level reference value P sent to the comparator 10 depending on the number of broadcast stations received in each tuning operation. be done. For this purpose, an additional system is controlled by the automatic tuner 2 to count how many traffic information broadcasting stations have reception levels equal to or higher than the level standard during each tuning period using the output of the station information decoder 6. A counter 11 is provided. The result taught by each channel selection scandal counter 11 is compared in a comparator 12 with a reference number inputted through, for example, a reference number step setting diamond 13. Ratio comparator 12 controls the fin pressure source for the variable reception level reference value. In the illustrated embodiment, this level reference value P
The generation source is an integrating amplifier 14, and a comparator 12 is connected to its input side.
A control voltage U from the counter 11 is applied; for example, this voltage is a positive voltage if the number of broadcast stations counted by the counter 11 is greater than a preset reference value, and a zero voltage if the number of the counter 11 matches the reference number. When the voltage and the number of broadcast stations taught by the counter 11 are less than the preset reference number, the voltage is negative. FIG. 2 schematically represents frequency spectra in the VHF range of various broadcast stations received during one channel selection operation.

In this case, it is assumed that only three broadcast stations with signals S1, S2 and S3 are traffic information broadcast stations. Comparator 1
At the value x assumed for the level reference value P of 0, the high frequency input levels (Hf) of all three broadcast stations exceed this value X, so all signals S1, S2 and S3 of the three broadcast stations are received. Ru. However, according to the present invention, all traffic information broadcasting stations within the tuning range are not analyzed, but in order to prevent the tuning operation from taking an unnecessarily long time, and preferably in one tuning operation. Only a limited number of traffic information broadcast stations are analyzed such that only traffic information broadcast stations that are received at a relatively high level during the time are analyzed in the message signal. Assume that only two traffic information broadcasting stations are received during one channel selection operation. Therefore, the reference number setting device 13
The reference number is set to “2”. When electricity enters the receiving device, the integrating amplifier 14 outputs the minimum reference value at the output side, y1.
As a result, all of the broadcast signals S1, S2 and S3. is received again. The comparator 12 supplies a positive voltage to the integrating amplifier 14, whose output voltage increases accordingly until it finally reaches the value y2 of the level reference value P per tuning period. This reference value is greater than the reception level of the broadcast signal S3, so only the two broadcast stations with broadcast signals SI and S2 are received. The counter 11 instructs the reference number "2" for each channel selection operation, and the comparator 12 instructs the integrating amplifier 14.
A zero voltage is applied to y2, and the level reference value P is maintained at this value y2. Only when the relationship between the levels changes in the process of the next channel selection operation, the level reference value also changes again from y2 in either the upward or downward direction until only two broadcast stations are received again. The integrating amplifier 14 is built so that when the receiving equipment is energized, the level does not start from the minimum reference value, Bell, but starts from the maximum reference value, Bell, and gradually decreases in level until it finally reaches the value y2. It is a good idea to do so.

This is because this ensures that initially only the strongest broadcasting station will be received. Furthermore, the positive or negative voltage value applied to the integrating amplifier 14 and the rate of change of the reference level accordingly can be made to depend on the difference between the number of received traffic information broadcasting stations and the reference value. It may also be expedient to provide a region signal decoder 15 which determines the region from which the traffic information is conveyed. This region information decoder 15 can be operated, for example, by a push button. This means that in certain regions only the traffic information stations of Süddeutsche Radio and Hetsen Broadcasting are tuned, or none of the traffic information stations from France are tuned. It is assumed that the broadcast signal SI in FIG. 2 comes from such an excluded broadcasting station. The automatic tuner 2 includes a region code decoder 15 so that tuning is automatically continued whenever a broadcast station is identified that does not have a transmission source in the selected region.
directly controlled by

The region signal decoder 15 is connected to the power counter 11 by applying the AND gate 16, and only those broadcasting stations having transmission sources in the selected region are automatically counted. The radio receiver for traffic information broadcasting according to the present invention also includes:
It can also be configured in a simple way so that broadcast stations with other signals can be received.

For example, special broadcasts or emergency broadcasts that take priority over any other traffic information broadcasts may be broadcast on specific frequencies, such as highways (
It is also possible to transmit via radio beacon transmitters located at specific (problematic) locations (on the Autobahn) or by special mobile transmitters belonging to the police, fire brigade, etc. In order to ensure that such special or emergency broadcasts are received, they must be left unselected regardless of the reception level. For this purpose, the automatic tuner 2 can be provided with an additional setting device, through which it can be provided with a defined frequency or frequency range of the entire frequency band to be selectively operated, and the tuning target traffic The reference number set by the information broadcasting station ensures that the comparison with the reference level is interrupted and special signals, such as emergency signals, can be analyzed.

For the traffic information radio peaker frequency range, the analysis of special signals can of course be omitted.

When an emergency broadcast station is received with a corresponding station signal and an emergency signal, the tuning is interrupted and an automatic transmission is performed via the AND gate 18 with the station signal decoder 6 so that the emergency call is received and further analyzed. The receiver itself can be equipped with an additional decoder 17 for this special signal, which controls the tuner 2. For subsequent analysis, the emergency broadcast is passed to the emergency call analyzer 19 by an additional switch (not shown) which is in turn controlled by the decoder 17.

If the emergency signal is transmitted as digital information, e.g. superimposed on voice or independent of a suitable emergency frequency, the decoder 17 is programmed with this digital information and cannot detect such a digital signal. When received, it is automatically delivered to the analyzer 19. The analyzer 19 can for example be equipped with a memory, in which the emergency information to be transmitted can be stored and passed on to a small transmitter located near the receiver for further transmission. It is possible. The functions of the control circuit 20 shown in FIG. 1 can also be performed by a microprocessor.

The reference level is produced, for example, by a digital-to-analog converter suitably controlled by a microprocessor and providing an associated analog reference level to the comparator 10. This operation is the same as described above. It is particularly advantageous to have level comparison and automatic tuning performed by a single and identical microprocessor. FIG. 3 shows one possibility for this. Decoders 6, 7 and possibly further decoders 15 and 1
The output of 7 is directly connected to the corresponding input of microprocessor 21. The microprocessor 21 controls a digital-to-analog converter 23 that supplies analog voltages necessary for tuning the receiving section 1. The digital data related to the high frequency reception level of the broadcasting station being received is analog. It is sent to the microprocessor 21 via a digital converter 22. The analog/digital converter 22 receives the analog reception level directly from the receiver 1. Using the circuit shown in FIG. 3, the same operation as described with respect to FIG. 1 is possible. If a microprocessor 21 is used for control, the circuit can be developed as shown in FIG. 4, and the tuning can be directly controlled by the microprocessor.

The microprocessor 21 also includes a random access memory 24 in which transmit frequencies and receive levels as well as additional data on the modulated signals for various broadcast stations are stored digitally. Receiver 1 is control bus 2
It has a digitally adjustable frequency synthesizer which can be controlled purely digitally by the microprocessor via 5. In this way, any receiving frequency determined via the microprocessor 21 can be quickly and accurately provided to the receiving section 1. The circuit in Figure 4 is similar to Figures 1 and 3.
No longer bound to a continuous tuning operation as described with respect to the figure, the microprocessor 21 uses the random access memory 2 according to the standards of the desired broadcaster.
This is because it is possible to classify the contents of 4 and directly supply digital data necessary for determining the most suitable broadcasting station to receive via the control bus 25.

Therefore, a radio receiver for traffic information broadcasting configured in this manner can analyze all of the broadcast stations received one after another by performing a one-time tuning operation controlled by the microprocessor 21 after, for example, a traffic information broadcast. Then, the obtained values such as the reception level and the station signal of the traffic broadcasting station are stored one after another in the random access memory 24. After the first tuning operation has been completed, the receiver 1 can be switched alternately to the desired preselected number of stations with the strongest signals, for example SI and S2, under direct control of the combiner. and then these stations can be analyzed alternately if there is a message signal. If one of these stations is transmitting a message signal, the receiver 1 remains tuned to that frequency and the low frequency part of the receiver is energized.

While switching to an individual selected station, other frequencies in the receiving band can be reconfigured and analyzed in sequence as needed for the changing millet frequency. In this way, it is possible to respond to dynamic changes in reception conditions, and to find a station again using a better reception method than that found in the initial channel selection operation and stored in the random access memory 24. Therefore, for example, while switching stations alternately between SI and S2 in the case of FIG.
The minimum level value yl is selected one after another without stopping.
can be analyzed for more than 10 broadcast stations.

In this case, it is desirable that stations whose broadcast signals have already reached a level relatively close to the reference level y2, such as the broadcast signal S3, are analyzed more frequently. This automatic operation with additional analysis can be easily enabled by a single and identical microprocessor 21'. Decoders 6, 7 and 15 can be omitted if each signal is decoded by a microprocessor, if the microprocessor is programmed accordingly. In this way the radio receiver according to the invention can be produced more easily and more economically.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a basic circuit of a radio receiver for traffic information broadcasting according to the present invention. FIG. 2 is an explanatory diagram schematically representing frequency spectra in the VHF range of various broadcasting stations received during one channel selection operation. FIG. 3 is a circuit block diagram of a radio receiver for traffic information broadcasting according to the present invention, in which bell comparison and automatic tuning are performed by a single and identical microprocessor. FIG. 4 is a circuit block diagram of a radio receiver for traffic information broadcasting according to the present invention, in which the microprocessor is equipped with a random access memory. In the figure, 1 is a receiver, 2 is an automatic tuner, 3 is a switch, 4 is a low frequency amplifier, Y5 is a speaker, 6 is a station signal decoder, 7 is a message signal decoder, 8 is a reception channel, and 9 is a AND gate, 10 is a comparator, 11 is a counter, 12 is a comparator, 13 is a reference number setting device, 14 is an integrating amplifier, 15 is a region signal decoder, 21 is a microprocessor, 22 is an analog
Digital converter, 23 is a digital-to-analog converter, 2
4 is a random access memory, and 25 is a control bus. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. An automatic tuner, a station signal decoder, a message signal decoder, a received level analyzer, and a control circuit controlled by the decoder and the analyzer, the control circuit controlling the station signal Only when it is determined from the output of a decoder etc. that a traffic information broadcasting station that is transmitting traffic information and is worthy of reception has been received, the channel selection operation is interrupted and that traffic information broadcasting station is selected. This is a radio receiver for traffic information broadcasting, which uses a comparison circuit to compare the reception level with an adjustable level reference value to determine which traffic information broadcasting stations are worth receiving. The level criterion is controlled based on the number of traffic information broadcast stations received during each tuning period to automatically adjust the number of traffic information broadcast stations received during each tuning period to a number preselected by the user. A radio receiver for traffic information broadcasting. 2. Claims characterized in that the level reference value is increased from a low level, and the traffic information broadcasting stations received at the maximum reception level are limited to a predetermined specific number. The radio receiver for traffic information broadcasting according to paragraph 1. 3. The reference level of the reception level analyzer changes slowly over the channel selection time until it reaches the level reference value, and at that value only a predetermined number of traffic information broadcasting stations are received, and then the level reference value is reached. The radio receiver for traffic information broadcasting according to claim 1, wherein the level reference value is maintained at the level reference value. 4 A counter controlled by a station signal decoder counts the number of traffic information broadcasting stations that exceed the level reference value during each selection, and the result is compared with a predetermined reference number. 4. The radio receiver for traffic information broadcasting according to claim 1, wherein the level reference value is set by this comparator. 5. Claim 4, characterized in that the comparator supplies an output voltage (±U) corresponding to the difference between the reference number and the actually counted number, said reference level being supplied to an integrating amplifier. A radio receiver for traffic information broadcasting described in . 6. The control circuit for controlling the automatic tuner is a microprocessor, in which the traffic information broadcast station received during one channel selection operation is analyzed in terms of frequency and reception level, and the input level is According to any one of claims 1 to 5, only broadcast stations that meet predetermined criteria are selected as worthy of reception for later selection. radio receiver for traffic information broadcasting. 7. A radio receiver for traffic information broadcasting according to claim 6, characterized in that the level reference value is produced by a digital-to-analog converter controlled by a microprocessor. 8. Claim 6 or 7, characterized in that the reception level determined by the reception section is supplied to the microprocessor for analysis via a digital-to-analog converter.
A radio receiver for traffic information broadcasting as described in Section 1. 9. The microprocessor is equipped with a memory, on the one hand, the transmission frequency and the traffic information broadcast signal together with the reception level are stored in said memory, and on the other hand, depending on whether this stored station data is worth receiving, Claims 1, 2, 3, 4, characterized in that the microprocessor and memory are connected to each other so that they can be classified by the microprocessor.
The radio receiver for traffic information broadcasting according to any one of Items 5, 6, 7, and 8. 10. Claims 1, 2, 3, 4, characterized in that the receiving part comprises a digitally adjustable frequency synthesizer controlled by a microprocessor for frequency adjustment of the supply or receiving part , 5, 6, 7, 8, or 9. 11 Claims 1, 2, 3, 4, 5, 6, characterized in that at least the station signal and the message signal are digitally analyzed in a microprocessor.
The radio receiver for traffic information broadcasting according to any one of items 7, 8, 9, and 10. 12 An automatic tuner, a station signal decoder, a message signal decoder, a region signal decoder, a received level analyzer, and a control circuit controlled by the decoder and the analyzer, and the control circuit is configured to perform station signal decoding. Only when it is determined from the output of the device that a traffic information broadcasting station that is transmitting traffic information and is worth receiving has been received, the channel selection operation is interrupted and the traffic information broadcasting station is selected. This is a radio receiver for traffic information broadcasting in some places, which uses a comparison circuit to compare the reception level with an adjustable level reference value to determine which traffic information broadcasting stations are worth receiving. The level reference value is controlled based on the number of traffic information broadcast stations received during each tuning period to automatically set the number of traffic information broadcast stations worthy of reception to a number preselected by the user. ,
A counter controlled by a station signal decoder counts the number of traffic information broadcast stations that exceed a preset level reference value during each selection, and the result is determined in advance. The reference number is compared with another comparator, and the level reference value is set by this comparator,
A radio receiver for traffic information broadcasting, characterized in that a counter is controlled via the region signal decoder so that only the other selected traffic information broadcasting station is included in the count. 13 An automatic tuner, a station signal decoder, a message signal decoder, a special signal decoder, a received level analyzer, and a control circuit controlled by the decoder and the analyzer, the control circuit being a station signal decoder. Only when it is determined from the output of the device that a traffic information broadcasting station that is transmitting traffic information and is worth receiving has been received, the channel selection operation is interrupted and the traffic information broadcasting station is selected. This is a radio receiver for traffic information broadcasting in some places, which uses a comparison circuit to compare the reception level with an adjustable level reference value to determine which traffic information broadcasting stations are worth receiving. The level reference value is controlled based on the number of traffic information broadcast stations received during each tuning period to automatically set the number of traffic information broadcast stations worthy of reception to a number preselected by the user. , traffic information broadcasting stations with special signals, in particular emergency signals, received in one or more predetermined areas within the entire frequency band scanned in the tuning operation, regardless of the reception level. A radio receiver for traffic information broadcasting, characterized in that it is included in a channel selection operation or not included in limiting the number of traffic information broadcasting stations worth receiving.