EP0443501A2 - RDS broadcast receiver with a device for accelerated seeking of alternative frequencies - Google Patents

RDS broadcast receiver with a device for accelerated seeking of alternative frequencies Download PDF

Info

Publication number
EP0443501A2
EP0443501A2 EP91102296A EP91102296A EP0443501A2 EP 0443501 A2 EP0443501 A2 EP 0443501A2 EP 91102296 A EP91102296 A EP 91102296A EP 91102296 A EP91102296 A EP 91102296A EP 0443501 A2 EP0443501 A2 EP 0443501A2
Authority
EP
European Patent Office
Prior art keywords
rds
frequency
frequencies
code
memory
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP91102296A
Other languages
German (de)
French (fr)
Other versions
EP0443501A3 (en
EP0443501B1 (en
Inventor
Dieter Grundig E.M.V. El. Mech. Versuchs. Nohse
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Grundig EMV Elektromechanische Versuchsanstalt Max Grundig GmbH
Original Assignee
Grundig EMV Elektromechanische Versuchsanstalt Max Grundig GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Grundig EMV Elektromechanische Versuchsanstalt Max Grundig GmbH filed Critical Grundig EMV Elektromechanische Versuchsanstalt Max Grundig GmbH
Publication of EP0443501A2 publication Critical patent/EP0443501A2/en
Publication of EP0443501A3 publication Critical patent/EP0443501A3/en
Application granted granted Critical
Publication of EP0443501B1 publication Critical patent/EP0443501B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
    • H04H20/20—Arrangements for broadcast or distribution of identical information via plural systems
    • H04H20/22—Arrangements for broadcast of identical information via plural broadcast systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H2201/00—Aspects of broadcast communication
    • H04H2201/10—Aspects of broadcast communication characterised by the type of broadcast system
    • H04H2201/13—Aspects of broadcast communication characterised by the type of broadcast system radio data system/radio broadcast data system [RDS/RBDS]

Definitions

  • RDS radio data system
  • PI codes Program Identification Codes
  • the radio receiver is tuned to an RDS station for the first time by manual tuning or by station search, it can take a long time until a list of alternative frequencies assigned to the currently received frequency is stored, since if reception of the RDS data is disturbed u. A multiple run of the AF lists may have to be waited until the decoding is unambiguous.
  • EN 50 067 not only waits for the AF list assigned to the currently received frequency, but also for the AF lists that are assigned to other transmission towers in the transmitter chain to ensure that the currently received frequency appears as AF of a different mother frequency. In this case, this mother frequency should be saved as an alternative frequency of the current reception frequency.
  • DE-PS 38 35 870 describes a method according to which, on the one hand, the decodable PI codes and, on the other hand, the receivable RDS frequencies with respective assignment to the corresponding PI codes are stored during an automatic or manually started station search.
  • the resulting AF lists which may be due to the reception conditions at the location of the recipient. May not include all the actually existing alternative frequencies in the program chain, are then supplemented by the AFs additionally contained in the RDS data signal.
  • the object of the present invention was to provide an RDS radio receiver, in particular an RDS car radio, with a device which, after a manually triggered RDS station search, supplements the RDS reception frequency transferred into the working memory with those alternative frequencies which are in a or more program memories of the Receiving device are stored with previous confirmation of their worthiness of receipt.
  • the PI codes of the RDS frequencies present in the program memories are compared with the PI code of the RDS reception frequency currently adopted in the working memory, and if they match, the alternative frequencies are transferred directly to the dynamic AF list of the working memory.
  • the advantage of this arrangement is that the AF lists that have grown empirically in the program memories over a longer period of time are immediately available and, if a frequency change is necessary, there is a probability that one or more alternative frequencies are also worth receiving. This is particularly useful if the transmission of the alternative frequencies in the RDS data signal is disturbed at the reception frequency found in the search.
  • the RDS radio receiver shown in FIG. 1 contains a synthesizer tuner 1, an IF amplifier 2 for the selective amplification and demodulation of the intermediate frequency, a stereo decoder 3 for decoding the stereo multiplex signal and a stereo power amplifier in a manner known per se 4.
  • the reception quality is monitored with the level detector 5 and the multipath detector 6.
  • the level detector 5 takes a measured variable from the IF amplifier 2 in accordance with the IF signal level to determine the signal field strength, while the multipath detector 6 evaluates high-frequency interference amplitudes in the multiplex signal caused by multipath reception.
  • the analog / digital conversion of the control signals for the microprocessor 9 takes place either in the two detectors 5, 6 or in the microprocessor 9, provided that it is provided with corresponding converter inputs.
  • the RDS demodulator 7 is also fed with the demodulated multiplex signal. After a 57 kHz bandpass filtering, the quadrature-amplitude-modulated RDS signal is demodulated and the digital data obtained after a subsequent biphase and differential decoding are fed to the microprocessor 9 for further processing.
  • the microprocessor 9 has the RAM memory 12 as the main memory.
  • the operating program is stored in the ROM memory 13.
  • the EEPROM memory 14 serves as a non-volatile program memory and contains in its individual memory levels for each stored program in addition to the PI code and the PS code (program service name code for displaying the name of a program chain in the display 10) a number of selected alternative frequencies for a spontaneous program call.
  • the AF lists of this program memory 14 are built up empirically over a longer period of time, because whenever the PI code of a frequency in the working memory 12 that has been checked for reception quality matches the PI code of a program memory, this frequency is a proven AF from the microprocessor 9 in FIG associated program memory is automatically transferred.
  • the program memories do not contain all of the alternative frequencies offered with the RDS data signal, but rather only a limited selection which is important for the device user in view of his usual travel route.
  • the access time when changing to an alternative frequency worth receiving is significantly reduced by this measure.
  • the microprocessor 9 will initiate a tuning and storage process, as exemplified in the flow chart according to FIG. 2.
  • step 1 After the start of the RDS station search, it is checked in program step 1 whether a frequency change lock is activated, since in this case no search command is accepted by the microprocessor 9 and the program is ended immediately. If the change lock is not active, the output stage 4 is muted in step 2 via the electronic switch 8 and the tuner 1 is tuned by the microprocessor 9 step by step. If the microprocessor 9 detects a station worth receiving in step 3, evaluating the signals from the level detector 5 and possibly additionally from the multipath detector 6, it first stops the search run and initializes a counter for the time t. In program step 5, the microprocessor 9 checks whether it receives 7 RDS signals via the RDS demodulator 7. If not, he continues this test via step 8 until the time t has exceeded the value t 1. In this case, the program returns to step 2, i.e. tuner 1 is further tuned.
  • step 7 If T1 RDS signals are decoded within the time, the microprocessor 9 checks in step 7 whether a valid PI code is recognized. This test, which also pays attention to the correct decoding of the TP bit (Traffic Program Bit) in a special search for RDS traffic radio stations, is continued up to a maximum of time t2; then the program feeds back to step 2 via step 8.
  • TP bit Traffic Program Bit
  • step 10 If the microprocessor 9 detects an error-free PI code, it takes over the relevant RDS or RDS-TP frequency in the working memory 12 in step 9 and removes the muting of the output stage 4.
  • program step 10 he activates a change lock so as not to receive any further search commands from the control unit 11 and sets a timer for the expiry time t ws to zero.
  • step 11 he compares the PI code of the frequency loaded into the working memory 12 with the PI codes of the frequencies contained in the program memories 14 (or equivalent additional memories) and, if they match in step 12, transmits the frequencies of the corresponding program memory level as alternative frequencies in the main memory 12.
  • Program step 13 leads back to step 11 as long as the expiry time t ws for the change lock has not reached the value t 3 . Only then is the exchange lock released in step 14 and the program run ended.
  • the quality rating of the alternative frequencies in the working memory 12 is updated and that alternative frequencies that are determined from the RDS data stream via wave propagation are subordinate in the evaluation sequence or, if no AFs could be taken over from the program memory 14, they are stored as the sole alternative frequencies. For this reason, the list of alternative frequencies in the working memory 12 can be referred to as a dynamic AF list.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Circuits Of Receivers In General (AREA)

Abstract

The subject matter of the invention relates to a radio receiver in the Radio Data System. To enable fast provision of a list of frequencies which are alternatives to a reception frequency located in the RDS transmitter search run, a device is disclosed with which frequencies which have already been tested, whose reception quality has been confirmed and which are stored under the same PI code, e.g. in the program memory of the unit, are transferred directly to the working memory. <IMAGE>

Description

Mit dem Radio-Daten-System (RDS) wird parallel zum ausgestrahlten Rundfunkprogramm, unhörbar für den Rundfunkhörer, ein binärer Datenstrom übertragen, der dem Empfangsgerät eine Reihe von Abstimm-, Schalt- und Betriebsinformationen liefert. Unter anderem werden z. B. als Abstimmhilfe fortlaufend sogenannte PI-Codes (Programme Identification Codes) gesendet, die dem Empfänger die Zuordnung einer Senderfrequenz zu einer bestimmten Programmkette erlauben und ihm alternative Frequenzen anbieten, mit denen das gleiche Programm empfangen werden kann. Dieser RDS-Service ist vor allem für mobile Rundfunkempfänger nützlich, weil sich durch Ortsveränderungen die Empfangsverhältnisse ständig ändern können.With the radio data system (RDS), a binary data stream is transmitted parallel to the broadcast radio program, inaudible to the radio listener, which provides the receiver with a range of tuning, switching and operating information. Among other things, e.g. B. continuously sent as a tuning aid so-called PI codes (Program Identification Codes), which allow the receiver to assign a transmitter frequency to a specific program chain and offer him alternative frequencies with which the same program can be received. This RDS service is particularly useful for mobile radio receivers because changes in location can change the reception conditions constantly.

Die Übertragung der alternativen Frequenzen vom Sender zum Empfänger über Wellenausbreitung kann aber im Grenzfall bis zu zwei Minuten dauern (störungsfreier Empfang vorausgesetzt), da die AFs in Form von Listen sequentiell übermittelt werden. Die Organisation dieser Listen, für die es zwei Varianten A und B gibt, ist in der Spezifikation des Radio-Daten-Systems, DIN pr. EN 50 067 vom Oktober 1988 ausführlich beschrieben und soll hier nicht näher erläutert werden.The transmission of alternative frequencies from the transmitter to the receiver via wave propagation can, however, take up to two minutes in the borderline case (more interference-free Reception required), since the AFs are transmitted sequentially in the form of lists. The organization of these lists, for which there are two variants A and B, is specified in the specification of the radio data system, DIN pr. EN 50 067 from October 1988 is described in detail and will not be explained here in detail.

Um den Rundfunkhörer ohne längere Unterbrechung mit dem laufenden Programm zu versorgen, ist es deshalb notwendig, daß das Empfangsgerät bei Verschlechterung der Empfangsverhältnisse innerhalb eines internen Speichers auf bereits registrierte alternative Frequenzen zurückgreifen kann. Dieses Verfahren, als eines der Grundlagen des Radio-Daten-Systems, ist aus der DE-PS 34 48 043 bekannt.In order to supply the radio listener with the current program without a long interruption, it is therefore necessary that the receiving device can fall back on alternative frequencies that have already been registered within an internal memory if the reception conditions deteriorate. This method, as one of the basics of the radio data system, is known from DE-PS 34 48 043.

Wird jedoch erstmalig der Rundfunkempfänger durch manuelle Abstimmung oder durch Sender-Suchlauf auf einen RDS-Sender eingestellt, so kann es sehr lange dauern, bis eine der aktuell empfangenen Frequenz zugeordnete Liste alternativer Frequenzen gespeichert ist, da bei gestörtem Empfang der RDS-Daten u. U. ein mehrfacher Durchlauf der AF-Listen bis zur eindeutigen Decodierung abgewartet werden muß.However, if the radio receiver is tuned to an RDS station for the first time by manual tuning or by station search, it can take a long time until a list of alternative frequencies assigned to the currently received frequency is stored, since if reception of the RDS data is disturbed u. A multiple run of the AF lists may have to be waited until the decoding is unambiguous.

Zur Verkürzung der Zeit und zur Erhöhung der Sicherheit bei der Generierung einer Liste alternativer Frequenzen im Speicher des Empfangsgerätes wird deshalb in der DE-PS 37 37 535 vorgeschlagen, bei der Übertragung alternativer Frequenzen vom Sender zum Empfänger entsprechend dem Verfahren B nach DIN pr. EN 50 067 nicht nur die der aktuell empfangenen Frequenz zugeordnete AF-Liste abzuwarten, sondern auch bei den AF-Listen, die anderen Sendetürmen der Senderkette zugeordnet sind, darauf zu achten, ob die aktuell empfangene Frequenz als AF einer anderen Mutterfrequenz auftaucht. In diesem Fall soll diese Mutterfrequenz als alternative Frequenz der aktuellen Empfangsfrequenz abgespeichert werden.To shorten the time and to increase security when generating a list of alternative frequencies in the memory of the receiving device is therefore proposed in DE-PS 37 37 535 when transmitting alternative frequencies from the transmitter to the receiver according to procedure B according to DIN pr. EN 50 067 not only waits for the AF list assigned to the currently received frequency, but also for the AF lists that are assigned to other transmission towers in the transmitter chain to ensure that the currently received frequency appears as AF of a different mother frequency. In this case, this mother frequency should be saved as an alternative frequency of the current reception frequency.

Der Nachteil dieses Verfahrens liegt darin, daß auch Frequenzen als vermeintliche AFs gespeichert werden können, die nicht der regionalen Liste der aktuell empfangenen Frequenz angehören. Ausgelöst wird diese Mehrdeutigkeit dadurch, daß eine Mutterfrequenz innerhalb des Sendegebietes einer Programmkette mehrfach zum Einsatz kommen kann. So sendet z. B. der Bayerische Rundfunk sein zweites Hörfunkprogramm auf einer Frequenz von 88,4 MHz sowohl über den Sender Ismaning bei München als auch über den Sender Pfaffenberg bei Aschaffenburg. Der Sender Pfaffenberg taucht als alternative Frequenz zum Sender Kreuzberg (93,1 MHz) in dessen regionaler AF-Liste auf. Wenn jetzt die Frequenz des Senders Kreuzberg als AF der z. B. aktuell empfangenen Frequenz des Senders Ismaning im regionalen Empfangsgebiet bei München abgespeichert wird, so ist diese Frequenz für einen schnellen Frequenzwechsel wertlos und verzögert nur den Abstimmvorgang auf eine empfangswürdigere alternative Frequenz.The disadvantage of this method is that frequencies can also be stored as supposed AFs that do not belong to the regional list of the currently received frequency. This ambiguity is triggered by the fact that a mother frequency can be used several times within the transmission area of a program chain. So z. B. Bayerischer Rundfunk broadcasts its second radio program on a frequency of 88.4 MHz via the Ismaning transmitter near Munich and the Pfaffenberg transmitter near Aschaffenburg. The Pfaffenberg transmitter appears as an alternative frequency to the Kreuzberg transmitter (93.1 MHz) in its regional AF list. If now the frequency of the Kreuzberg transmitter as AF the z. B. the currently received frequency of the transmitter Ismaning is stored in the regional reception area near Munich, this frequency is worthless for a quick frequency change and only delays the tuning process to a more acceptable alternative frequency.

DE-PS 38 35 870 beschreibt demgegenüber ein Verfahren, nach dem während eines automatischen oder manuell gestarteten Sendersuchlaufs einerseits die decodierbaren PI-Codes und andererseits die empfangbaren RDS-Frequenzen mit jeweiliger Zuordnung zu den entsprechenden PI-Codes gespeichert werden. Diese so entstandenen AF-Listen, die wegen der Empfangsverhältnisse am Standort des Empfängers u. U. nicht alle tatsächlich vorhandenen alternativen Frequenzen der Programmkette beinhalten, werden anschließend durch die zusätzlich im RDS-Datensignal enthaltenen AFs ergänzt.DE-PS 38 35 870, on the other hand, describes a method according to which, on the one hand, the decodable PI codes and, on the other hand, the receivable RDS frequencies with respective assignment to the corresponding PI codes are stored during an automatic or manually started station search. The resulting AF lists, which may be due to the reception conditions at the location of the recipient. May not include all the actually existing alternative frequencies in the program chain, are then supplemented by the AFs additionally contained in the RDS data signal.

Dieses Verfahren führt zwar zu einem beschleunigten Aufbau der AF-Listen im geräteeigenen Speicher, zeigt aber Mängel in Bezug auf die wirklich vorhandene Empfangsqualität der alternativen Frequenzen in einem bestimmten Empfangsgebiet, da eine Bewertung der Empfangswürdigkeit innerhalb des individuellen alltäglichen Aktionskreises des Rundfunkhörers, speziell des Autofahrers, nicht vorgenommen wird.Although this procedure leads to an accelerated build-up of the AF lists in the device's own memory, it shows shortcomings with regard to the really existing reception quality of the alternative frequencies in a certain reception area, since an assessment of the reception worthiness within the individual everyday action group of the radio listener, especially the driver , is not made.

Aufgabe der vorliegenden Erfindung war es demgegenüber, einen RDS-Rundfunkempfänger, insbesondere ein RDS-Autoradio, mit einer Einrichtung zu versehen, die nach einem manuell ausgelösten RDS-Sendersuchlauf die in den Arbeitsspeicher übernommene RDS-Empfangsfrequenz mit denjenigen alternativen Freqenzen ergänzt, welche in einem oder mehreren Programmspeichern des Empfangsgerätes mit vorausgegangener Bestätigung ihrer Empfangswürdigkeit abgelegt sind. Zu diesem Zweck werden die PI-Codes der in den Programmspeichern vorhandenen RDS-Frequenzen mit dem PI-Code der in den Arbeitsspeicher aktuell übernommenen RDS-Empfangsfrequenz verglichen, und bei Übereinstimmung werden die alternativen Frequenzen direkt in die dynamische AF-Liste des Arbeitsspeichers übertragen.In contrast, the object of the present invention was to provide an RDS radio receiver, in particular an RDS car radio, with a device which, after a manually triggered RDS station search, supplements the RDS reception frequency transferred into the working memory with those alternative frequencies which are in a or more program memories of the Receiving device are stored with previous confirmation of their worthiness of receipt. For this purpose, the PI codes of the RDS frequencies present in the program memories are compared with the PI code of the RDS reception frequency currently adopted in the working memory, and if they match, the alternative frequencies are transferred directly to the dynamic AF list of the working memory.

Der Vorteil dieser Anordnung liegt darin, daß die in den Programmspeichern über längeren Zeitraum empirisch gewachsenen AF-Listen sofort zur Verfügung stehen und bei einem notwendigen Frequenzwechsel die Wahrscheinlichkeit besteht, daß eine oder mehrere Ausweichfrequenzen auch empfangswürdig sind. Dies ist besonders nützlich, wenn bei der im Suchlauf gefundenen Empfangsfrequenz die Übertragung der alternativen Frequenzen im RDS-Datensignal gestört ist.The advantage of this arrangement is that the AF lists that have grown empirically in the program memories over a longer period of time are immediately available and, if a frequency change is necessary, there is a probability that one or more alternative frequencies are also worth receiving. This is particularly useful if the transmission of the alternative frequencies in the RDS data signal is disturbed at the reception frequency found in the search.

Die Erfindung, deren wesentliche Merkmale im Anspruch 1 aufgeführt und für die vorteilhafte Ausgestaltungen in den Unteransprüchen dargelegt sind, wird nachstehend anhand der Zeichnungen erläutert.The invention, the essential features of which are set out in claim 1 and set out for the advantageous embodiments in the subclaims, is explained below with reference to the drawings.

Es zeigt:

Fig. 1
das Blockschaltbild für ein Ausführungsbeispiel des erfindungsgemäßen Rundfunkempfängers
Fig. 2
ein Flußdiagramm für den Steuerungsablauf beim manuellen Auslösen des RDS-Sendersuchlaufes
It shows:
Fig. 1
the block diagram for an embodiment of the radio receiver according to the invention
Fig. 2
a flowchart for the control sequence when manually triggering the RDS station search

Der in Fig. 1 dargestellte RDS-Rundfunkempfänger enthält in an sich bekannter Weise einen Synthesizer-Tuner 1, einen ZF-Verstärker 2 zum selektiven Verstärken und Demodulieren der Zwischenfrequenz, einen Stereo-Decoder 3 zum Decodieren des Stereo-Multiplexsignals und eine Stereo-Endstufe 4. Als zentrale Steuereinheit, verbunden mit dem Bedienteil 11, dient der Mikroprozessor 9, der auch zur Senderabstimmung das notwendige Abstimmsignal an den Synthesizer-Tuner 1 liefert. Die Empfangsqualität wird mit dem Pegeldetektor 5 und dem Mehrwegedetektor 6 überwacht. Der Pegeldetektor 5 entnimmt dem ZF-Verstärker 2 nach Maßgabe des ZF-Signalpegels eine Meßgröße zur Feststellung der Signalfeldstärke, während der Mehrwegedetektor 6 hochfrequente Störamplituden im Multiplexsignal, verursacht durch Mehrwegeempfang, auswertet. Die Analog-/Digitalwandlung der Steuersignale für den Mikroprozessor 9 erfolgt entweder in den beiden Detektoren 5, 6 oder im Mikroprozessor 9, sofern er mit entsprechenden Wandlereingängen versehen ist. Der RDS-Demodulator 7 wird ebenfalls mit dem demodulierten Multiplexsignal gespeist. Nach einer 57 kHz-Bandpaßfilterung wird das in Quadratur amplitudenmodulierte RDS-Signal demoduliert und die nach einer anschließenden Biphase- und Differential-Decodierung gewonnenen digitalen Daten zur Weiterverarbeitung dem Mikroprozessor 9 zugeführt.The RDS radio receiver shown in FIG. 1 contains a synthesizer tuner 1, an IF amplifier 2 for the selective amplification and demodulation of the intermediate frequency, a stereo decoder 3 for decoding the stereo multiplex signal and a stereo power amplifier in a manner known per se 4. The microprocessor 9, which also supplies the necessary tuning signal to the synthesizer tuner 1 for tuning the transmitter, serves as the central control unit, connected to the control unit 11. The reception quality is monitored with the level detector 5 and the multipath detector 6. The level detector 5 takes a measured variable from the IF amplifier 2 in accordance with the IF signal level to determine the signal field strength, while the multipath detector 6 evaluates high-frequency interference amplitudes in the multiplex signal caused by multipath reception. The analog / digital conversion of the control signals for the microprocessor 9 takes place either in the two detectors 5, 6 or in the microprocessor 9, provided that it is provided with corresponding converter inputs. The RDS demodulator 7 is also fed with the demodulated multiplex signal. After a 57 kHz bandpass filtering, the quadrature-amplitude-modulated RDS signal is demodulated and the digital data obtained after a subsequent biphase and differential decoding are fed to the microprocessor 9 for further processing.

Als Arbeitsspeicher besitzt der Mikroprozessor 9 den RAM-Speicher 12. Das Betriebsprogramm ist im ROM-Speicher 13 abgelegt. Der EEPROM-Speicher 14 dient als nichtflüchtiger Programmspeicher und beinhaltet in seinen einzelnen Speicherebenen für jedes abgespeicherte Programm neben dem PI-Code und dem PS-Code (Programme Service Name Code zur Anzeige des Namens einer Programmkette im Display 10) eine Anzahl ausgewählter alternativer Frequenzen für einen spontanen Programmabruf. Die AF-Listen dieser Programmspeicher 14 werden über längeren Zeitraum empirisch aufgebaut, da immer dann, wenn der PI-Code einer auf Empfangsqualität geprüften Frequenz im Arbeitsspeicher 12 mit dem PI-Code eines Programmspeichers übereinstimmt, diese Frequenz als bewährte AF vom Mikroprozessor 9 in den zugehörigen Programmspeicher automatisch übertragen wird. Dadurch enthalten die Programmspeicher nicht sämtliche mit dem RDS-Datensignal angebotenen alternativen Frequenzen, sondern nur eine begrenzte Auswahl, die für den Gerätebenutzer in Anbetracht seiner üblichen Reiseroute wichtig ist. Die Zugriffszeit beim Wechsel auf eine empfangswürdige alternative Frequenz wird durch diese Maßnahme erheblich verkürzt.The microprocessor 9 has the RAM memory 12 as the main memory. The operating program is stored in the ROM memory 13. The EEPROM memory 14 serves as a non-volatile program memory and contains in its individual memory levels for each stored program in addition to the PI code and the PS code (program service name code for displaying the name of a program chain in the display 10) a number of selected alternative frequencies for a spontaneous program call. The AF lists of this program memory 14 are built up empirically over a longer period of time, because whenever the PI code of a frequency in the working memory 12 that has been checked for reception quality matches the PI code of a program memory, this frequency is a proven AF from the microprocessor 9 in FIG associated program memory is automatically transferred. As a result, the program memories do not contain all of the alternative frequencies offered with the RDS data signal, but rather only a limited selection which is important for the device user in view of his usual travel route. The access time when changing to an alternative frequency worth receiving is significantly reduced by this measure.

Wird über das Bedienteil 11 ein RDS-Sendersuchlauf gestartet, so wird der Mikroprozessor 9 einen Abstimm- und Speichervorgang einleiten, wie er im Flußdiagramm nach Fig. 2 beispielhaft dargestellt ist.If an RDS station search is started via the control unit 11, the microprocessor 9 will initiate a tuning and storage process, as exemplified in the flow chart according to FIG. 2.

Nach dem Start des RDS-Sendersuchlaufs wird im Programmschritt 1 geprüft, ob eine Frequenzwechselsperre aktiviert ist, da in diesem Fall kein Suchlaufbefehl vom Mikroprozessor 9 angenommen und das Programm sofort beendet wird. Ist die Wechselsperre nicht aktiv, so wird im Schritt 2 die Endstufe 4 über den elektronischen Schalter 8 stummgeschaltet und der Tuner 1 vom Mikroprozessor 9 schrittweise durchgestimmt. Erkennt der Mikroprozessor 9 im Schritt 3 einen empfangswürdigen Sender, wobei er die Signale des Pegeldetektors 5 und eventuell zusätzlich des Mehrwegedetektors 6 auswertet, so stoppt er zunächst den Suchlauf und initialisiert einen Zähler für die Zeit t. Im Programmschritt 5 kontrolliert der Mikroprozessor 9, ob er über den RDS-Demodulator 7 RDS-Signale erhält. Wenn nicht, setzt er diese Prüfung über Schritt 8 so lange fort, bis die Zeit t den Wert t₁ überschritten hat. In diesem Fall kehrt das Programm zum Schritt 2 zurück, d.h., der Tuner 1 wird weiter durchgestimmt.After the start of the RDS station search, it is checked in program step 1 whether a frequency change lock is activated, since in this case no search command is accepted by the microprocessor 9 and the program is ended immediately. If the change lock is not active, the output stage 4 is muted in step 2 via the electronic switch 8 and the tuner 1 is tuned by the microprocessor 9 step by step. If the microprocessor 9 detects a station worth receiving in step 3, evaluating the signals from the level detector 5 and possibly additionally from the multipath detector 6, it first stops the search run and initializes a counter for the time t. In program step 5, the microprocessor 9 checks whether it receives 7 RDS signals via the RDS demodulator 7. If not, he continues this test via step 8 until the time t has exceeded the value t 1. In this case, the program returns to step 2, i.e. tuner 1 is further tuned.

Werden innerhalb der Zeit t₁ RDS-Signale decodiert, so prüft der Mikroprozessor 9 im Schritt 7, ob ein gültiger PI-Code erkannt wird. Diese Prüfung, die bei einem speziellen Suchlauf nach RDS-Verkehrsfunksendern auch auf die einwandfreie Decodierung des TP-Bits (Traffic Programme Bit) achtet, wird maximal bis zur Zeit t₂ fortgesetzt; danach koppelt das Programm über Schritt 8 zum Schritt 2 zurück.If T₁ RDS signals are decoded within the time, the microprocessor 9 checks in step 7 whether a valid PI code is recognized. This test, which also pays attention to the correct decoding of the TP bit (Traffic Program Bit) in a special search for RDS traffic radio stations, is continued up to a maximum of time t₂; then the program feeds back to step 2 via step 8.

Erkennt der Mikroprozessor 9 einen fehlerfreien PI-Code, so übernimmt er im Schritt 9 die betreffende RDS- bzw. RDS-TP-Frequenz in den Arbeitsspeicher 12 und hebt die Stummschaltung der Endstufe 4 auf. Im Programmschritt 10 aktiviert er eine Wechselsperre, um keinen weiteren Suchlaufbefehl vom Bedienteil 11 entgegenzunehmen und setzt einen Timer für die Ablaufzeit tws auf Null. Anschließend vergleicht er im Schritt 11 den PI-Code der in den Arbeitsspeicher 12 geladenen Frequenz mit den PI-Codes der in den Programmspeichern 14 (oder gleichwertigen Zusatzspeichern) enthaltenen Frequenzen und überträgt bei Übereinstimmung im Schritt 12 die Frequenzen der entsprechenden Programmspeicherebene als alternative Frequenzen in den Arbeitsspeicher 12. Programmschritt 13 führt zum Schritt 11 zurück, solange die Ablaufzeit tws für die Wechselsperre nicht den Wert t₃ erreicht hat. Erst danach wird im Schritt 14 die Wechselsperre aufgehoben und der Programmdurchlauf beendet.If the microprocessor 9 detects an error-free PI code, it takes over the relevant RDS or RDS-TP frequency in the working memory 12 in step 9 and removes the muting of the output stage 4. In program step 10, he activates a change lock so as not to receive any further search commands from the control unit 11 and sets a timer for the expiry time t ws to zero. Then in step 11 he compares the PI code of the frequency loaded into the working memory 12 with the PI codes of the frequencies contained in the program memories 14 (or equivalent additional memories) and, if they match in step 12, transmits the frequencies of the corresponding program memory level as alternative frequencies in the main memory 12. Program step 13 leads back to step 11 as long as the expiry time t ws for the change lock has not reached the value t 3 . Only then is the exchange lock released in step 14 and the program run ended.

Nicht dargestellt ist im Flußdiagramm nach Fig. 2, daß bei jedem Frequenzwechsel aufgrund sich verschlechternder Empfangsverhältnisse die Qualitätsbewertung der alternativen Frequenzen im Arbeitsspeicher 12 aktualisiert wird und daß alternative Frequenzen, die aus dem RDS-Datenstrom über Wellenausbreitung ermittelt werden, in der Bewertungsfolge nachrangig oder, falls keine AFs aus dem Programmspeicher 14 übernommen werden konnten, als alleinige Alternativfrequenzen abgespeichert werden. Aus diesem Grund kann die Liste alternativer Frequenzen im Arbeitsspeicher 12 als dynamische AF-Liste bezeichnet werden.Not shown in the flowchart according to FIG. 2 is that with each frequency change due to deteriorating reception conditions, the quality rating of the alternative frequencies in the working memory 12 is updated and that alternative frequencies that are determined from the RDS data stream via wave propagation are subordinate in the evaluation sequence or, if no AFs could be taken over from the program memory 14, they are stored as the sole alternative frequencies. For this reason, the list of alternative frequencies in the working memory 12 can be referred to as a dynamic AF list.

Claims (3)

RDS-Rundfunkempfänger, insbesondere RDS-Autoradio mit elektronischen Abstimm- und Speicherelementen, mit einer Einrichtung zur Beurteilung der Empfangsqualität, mit Programmspeicher für den spontanen Zugriff auf verschiedene Rundfunkprogramme und mit einer zentralen Steuereinheit, dadurch gekennzeichnet, daß die zentrale Steuereinheit (9) nach einem RDS-Sendersuchlauf den PI-Code einer in den Arbeitsspeicher (12) übertragenen Empfangsfrequenz mit dem PI-Code der in den Programmspeicherebenen (14) enthaltenen Frequenzen vergleicht und bei Übereinstimmung die Frequenzen des betreffenden Programmspeichers direkt als alternative Frequenzen in den Arbeitsspeicher (12) überträgt.RDS radio receiver, in particular RDS car radio with electronic tuning and memory elements, with a device for assessing the reception quality, with program memory for spontaneous access to various radio programs and with a central control unit, characterized in that the central control unit (9) according to a RDS station search compares the PI code of a reception frequency transmitted into the main memory (12) with the PI code of the frequencies contained in the program memory levels (14) and, if they match, transmits the frequencies of the relevant program memory directly into the main memory (12) as alternative frequencies . RDS-Rundfunkempfänger nach Anspruch 1, dadurch gekennzeichnet, daß die zentrale Steuereinheit (9) als Mikroprozessor ausgebildet ist, der bei einem manuell ausgelösten RDS-Sendersuchlauf den Tuner (1) auf die nächstfolgende Frequenz mit ausreichender Empfangsqualität abstimmt und diese Frequenz nur dann in den Arbeitsspeicher (12) überträgt, wenn innerhalb einer ersten Zeitspanne (t₁) RDS-Signale decodiert und innerhalb einer zweiten Zeitspanne (t₂) ein fehlerfreier PI-Code erkannt wird.RDS radio receiver according to claim 1, characterized in that the central control unit (9) is designed as a microprocessor which, in the case of a manually triggered RDS station search, tunes the tuner (1) to the next frequency with sufficient reception quality and this frequency only then in the Main memory (12) transfers if RDS signals are decoded within a first time period (t 1) and an error-free PI code is recognized within a second time period (t 2). RDS-Rundfunkempfänger nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, daß nach Übernahme einer neuen RDS-Empfangsfrequenz in den Arbeitsspeicher (12) eine Wechselsperre für eine Zeitdauer (t₃) einsetzt, während der vom Mikroprozessor (9) kein neuer Suchlaufbefehl angenommen wird, so daß der PI-Code der in den Arbeitsspeicher (12) aktuell eingeschrieben Frequenz mit den PI-Codes der in den Programmspeicherebenen (14) abgelegten Frequenzen verglichen werden kann.RDS radio receiver according to one of the preceding claims, characterized in that after taking over a new RDS reception frequency in the working memory (12) a change lock for a period (t₃) during which no new search command is accepted by the microprocessor (9), so that the PI code of the frequency currently written into the main memory (12) can be compared with the PI code of the frequencies stored in the program memory levels (14).
EP91102296A 1990-02-21 1991-02-19 RDS broadcast receiver with a device for accelerated seeking of alternative frequencies Expired - Lifetime EP0443501B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4005413A DE4005413C2 (en) 1990-02-21 1990-02-21 RDS radio receiver with a facility for the accelerated finding of alternative frequencies
DE4005413 1990-02-21

Publications (3)

Publication Number Publication Date
EP0443501A2 true EP0443501A2 (en) 1991-08-28
EP0443501A3 EP0443501A3 (en) 1992-04-22
EP0443501B1 EP0443501B1 (en) 1996-06-12

Family

ID=6400636

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91102296A Expired - Lifetime EP0443501B1 (en) 1990-02-21 1991-02-19 RDS broadcast receiver with a device for accelerated seeking of alternative frequencies

Country Status (2)

Country Link
EP (1) EP0443501B1 (en)
DE (2) DE4005413C2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0552442A2 (en) * 1991-11-28 1993-07-28 Kabushiki Kaisha Kenwood Radio data system receiver
US5961126A (en) * 1996-07-02 1999-10-05 Ishikawa Gasket Co., Ltd. Metal gasket with peripheral bead

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4137000C2 (en) * 1991-11-11 1994-06-09 Opel Adam Ag Method for field strength-dependent evaluation of radio information for vehicles

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0305172A2 (en) 1987-08-24 1989-03-01 British Broadcasting Corporation Radio data system receivers
DE3835870C1 (en) 1988-10-21 1990-01-18 Blaupunkt-Werke Gmbh, 3200 Hildesheim, De

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3448043C2 (en) * 1984-09-07 1987-01-15 Institut für Rundfunktechnik GmbH, 8000 München Method for transmitting and processing digital information contained in a broadcast signal
DE3737535C1 (en) * 1987-11-05 1989-05-18 Blaupunkt Werke Gmbh Receiver for the radio data system
DE3825812A1 (en) * 1988-07-29 1990-02-01 Metz Werke Gmbh & Co Kg HIGH-FREQUENCY RECEIVER WITH A DEVICE FOR DISPLAYING THE PROGRAM IDENTIFICATION OF TRANSMITTERS
JPH082030B2 (en) * 1990-01-31 1996-01-10 パイオニア株式会社 RDS preset receiver

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0305172A2 (en) 1987-08-24 1989-03-01 British Broadcasting Corporation Radio data system receivers
DE3835870C1 (en) 1988-10-21 1990-01-18 Blaupunkt-Werke Gmbh, 3200 Hildesheim, De

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0552442A2 (en) * 1991-11-28 1993-07-28 Kabushiki Kaisha Kenwood Radio data system receiver
EP0552442A3 (en) * 1991-11-28 1995-03-22 Kenwood Corp
US5961126A (en) * 1996-07-02 1999-10-05 Ishikawa Gasket Co., Ltd. Metal gasket with peripheral bead

Also Published As

Publication number Publication date
DE4005413C2 (en) 1993-12-16
EP0443501A3 (en) 1992-04-22
DE59107910D1 (en) 1996-07-18
DE4005413A1 (en) 1991-08-22
EP0443501B1 (en) 1996-06-12

Similar Documents

Publication Publication Date Title
EP0459360B1 (en) RDS broadcast receiver with a device for searching for currently receivable alternative frequencies
DE69114238T2 (en) Procedure for selecting the reception frequency for an RDS receiver.
DE69124764T2 (en) Automatic radio wave tuner for RDS receivers
EP0415132B1 (en) RDS broadcast receiver with device for automatically switching over to an alternative regional programme
DE3938457C2 (en) RDS radio receiver with a facility for country-specific evaluation of RDS data
EP0403744B1 (en) RDS broadcast receiver with empirically growing memory contents in its program memories
DE2850733A1 (en) VHF radio receiver with automatic tuning suppression - is operative only when decoded received regional code equals stored regional transmitter code
EP0579955B1 (en) Tuning of a receiver according to the language of transmitter
EP0364749B1 (en) Radio receiver
EP0443436B1 (en) Method for selecting a broadcast programme
DE69525564T2 (en) Process for the acquisition of PTY burst signals in radio data receivers
EP0433904B1 (en) RDS broadcast receiver with a device for preferential reception of programs with the same country code
EP0443501B1 (en) RDS broadcast receiver with a device for accelerated seeking of alternative frequencies
DE69523510T2 (en) RDS receiver using EON information
DE69520911T2 (en) Method of an RDS receiver for controlling a program interruption
EP1241812B1 (en) Method for determining an RDS-code with a broadcast receiver
DE19531527C2 (en) Method and circuit arrangement for changing the program in the event of a brief signal failure
DE4425194B4 (en) Method and device for determining the location of a radio receiver
DE4038597C2 (en)
DE19746960B4 (en) Method for storing data of broadcast transmission frequencies in a data memory of a radio receiver
DE4428314A1 (en) RDS receiver with channel presetting function
EP0862814B1 (en) Method of selecting a transmit frequency
DE19531367A1 (en) RDS receiver

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB IT

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR GB IT

17P Request for examination filed

Effective date: 19920921

17Q First examination report despatched

Effective date: 19950111

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: GRUNDIG E.M.V. ELEKTRO-MECHANISCHE VERSUCHSANSTALT

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

REF Corresponds to:

Ref document number: 59107910

Country of ref document: DE

Date of ref document: 19960718

ET Fr: translation filed
GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19960726

ITF It: translation for a ep patent filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20100218

Year of fee payment: 20

Ref country code: FR

Payment date: 20100223

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20100202

Year of fee payment: 20

Ref country code: DE

Payment date: 20100226

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 59107910

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20110218

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20110218

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20110219