EP0714183A2 - Méthode pour la synchronisation d'un récepteur RDS et récepteur de radiodiffusion utilisant cette méthode - Google Patents

Méthode pour la synchronisation d'un récepteur RDS et récepteur de radiodiffusion utilisant cette méthode Download PDF

Info

Publication number
EP0714183A2
EP0714183A2 EP95118045A EP95118045A EP0714183A2 EP 0714183 A2 EP0714183 A2 EP 0714183A2 EP 95118045 A EP95118045 A EP 95118045A EP 95118045 A EP95118045 A EP 95118045A EP 0714183 A2 EP0714183 A2 EP 0714183A2
Authority
EP
European Patent Office
Prior art keywords
data stream
bit sequence
word
code
radio
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.)
Withdrawn
Application number
EP95118045A
Other languages
German (de)
English (en)
Other versions
EP0714183A3 (fr
Inventor
Joachim Bischoff
Volker Heicappell
Reiner Klos
Wolfgang Trinks
Guido Zehnle
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.)
Harman Becker Automotive Systems GmbH
Original Assignee
Becker 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
Priority claimed from DE19944441789 external-priority patent/DE4441789C1/de
Application filed by Becker GmbH filed Critical Becker GmbH
Publication of EP0714183A2 publication Critical patent/EP0714183A2/fr
Publication of EP0714183A3 publication Critical patent/EP0714183A3/fr
Withdrawn legal-status Critical Current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
    • H04H20/28—Arrangements for simultaneous broadcast of plural pieces of information
    • H04H20/33—Arrangements for simultaneous broadcast of plural pieces of information by plural channels
    • H04H20/34—Arrangements for simultaneous broadcast of plural pieces of information by plural channels using an out-of-band subcarrier signal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H40/00—Arrangements specially adapted for receiving broadcast information
    • H04H40/18—Arrangements characterised by circuits or components specially adapted for receiving
    • 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

  • the present invention relates to a method for synchronizing a radio receiver, which operates in a radio system in which, in addition to the actual program, additional information, such as a program identification (PI) code, is transmitted in the form of a serially transmitted binary data stream, the data stream being divided into individual ones Blocks is divided, each containing a so-called offset word, a useful word, in particular a radio data system (RDS) receiver for the received data stream, by examining the received data stream for the presence of a known bit sequence.
  • PI program identification
  • RDS radio data system
  • the present invention relates to a radio receiver that works according to this method.
  • a binary data stream is transmitted inaudibly for the radio listener, which contains a series of tuning, switching and operating information.
  • a program identification code (PI code) is continuously transmitted as a tuning aid, which allows the assignment of a transmission frequency to a program chain.
  • the offset words contained in each transmitted block are used for synchronization with the data stream.
  • the offset words in this system each have a length of ten bits and there are a total of five different offset words, so that every 5 x 210 bits are random a bit sequence occurs that corresponds to one of the offset words. Due to the transmission rate of the data stream, this means that the bit sequence of an offset word occurs randomly after every six seconds. This error rate is prohibitively high, so that pure block synchronization is not sufficient.
  • a group synchronization is therefore additionally carried out in that the synchronization is only considered complete when two offset words are found offset from one another by a block or more. This means that at least two valid blocks must be recognized before synchronization is complete. Accordingly, the synchronization time is at least the transmission time of two blocks.
  • reception conditions With poor reception conditions, it is difficult to identify two fully received offset words at intervals of one or more blocks, since the error rate of the received RDS signals is then correspondingly high. Especially when reception conditions are poor, it is important to check alternative frequencies and to have as many alternative frequencies identified as possible in order to be able to switch back and forth between them. If the synchronization now takes too long, the associated alternative frequencies either cannot be identified or there are mute pauses that lie above the hearing threshold.
  • the invention is therefore based on the object of specifying a method for synchronizing a radio receiver of the type mentioned at the outset, which enables faster synchronization and, in particular even in the case of poor reception conditions, ensures that alternative frequencies are found without long mute pauses.
  • This object is achieved in that at least part of an expected useful word is used for synchronization, in that the data stream is at least also examined for the presence of the bit sequence of the expected useful word or part of the useful word.
  • the useful words have a length of 16 bits, so that a longer bit sequence is available for synchronization than the bit sequence used in known methods.
  • another known word in particular one relating to the useful word, can also be used according to the invention appropriate offset word can be used.
  • the data stream is therefore not examined, or not only for the presence of the known bit sequence of an offset word, but at least also for the bit sequence of an expected useful word or useful word part.
  • the error probability resulting from the random occurrence of the bit sequence being sought is correspondingly reduced in the method according to the invention.
  • Group synchronization can therefore be dispensed with and only one block from the data stream must be received without errors.
  • the invention takes advantage of the fact that in many cases a useful word or part of a useful word is known, so that one knows that the data stream of the received program must contain a certain useful word. For example, when searching for an alternative frequency to a set program, the PI code of the program is known, since this is transmitted with the received program. The same also applies when searching for a frequency on the basis of a stored PI code in order to carry out a so-called station order or switch-on confirmation process, in which all frequencies belonging to a stored PI code are searched for and the frequency with the best reception quality is set.
  • the duration of a synchronization process in the method according to the invention is significantly shortened compared to the known methods. This has an effect in particular in the case of poor reception conditions, since here the error rate of the received RDS signals is particularly high and it is therefore very difficult to find two complete offset words at a distance of one or more blocks from one another.
  • the advantages according to the invention also occur not only when frequencies are switched on or off, but also when there is a loss of synchronization during reception.
  • program identification code In addition to the program identification code already mentioned, other expected useful words can also be used for synchronization, in particular in conjunction with the associated offset words.
  • the program identification code can be used for synchronization both with and without the regionalization part, that is to say the part which identifies a regional subroutine.
  • a shift register is preferably used to check the data stream for the bit sequence sought, the content of which is compared with the bit sequence sought in a memory after each input of a new bit.
  • a test template is, so to speak, placed over the received data stream.
  • the radio receiver for carrying out the synchronization method according to the invention has means for at least examining the data stream for the presence of the bit sequence of at least part of an expected useful word, the means preferably having a shift register for the received data stream and a memory for the bit Episode include.
  • At least part of the PI code of a set or searched radio program, in particular in connection with an associated offset word, can be stored as part of the bit sequence sought.
  • This embodiment is particularly advantageous in the case of a radio receiver which has means for searching for all reception frequencies associated with a PI code stored in a memory and for setting the frequency with the best reception quality.
  • the PI code of the frequency sought in each case is known and can therefore be used for synchronization.
  • the figure shows a binary data stream 1, which consists of a serial sequence of individual bits 2.
  • the data stream 1 is divided into blocks 3 of twenty-six bits each, of which ten bits each represent an offset word 4 and sixteen bits a useful word 5.
  • the data stream 1 flows in the direction of the arrow 6. Accordingly, the offset words 4 are arranged at the beginning of each block 3.
  • the bit sequence 7 consists of twenty-six bits 8, thus has the same bit length as a block 3 of the data stream 1.
  • the bit sequence 7 stored in the memory corresponds to the bit sequence of an offset word 4 and a subsequent expected useful word 5.
  • the data stream 1 is now pushed through a shift register 9, the length of which corresponds to the length of the bit sequence 7 stored in the memory.
  • a bit is inserted into the shift register 9, its content is compared bit by bit with the bits of the bit sequence 7 contained in the memory.
  • the bit sequence 7 is thus placed over the serial data stream 1 like a template and checked for agreement with the bit sequence of the data stream.
  • the synchronization is complete as soon as a matching bit sequence has been found in the data stream.
  • the PI code is used, which is known from the received RDS data when searching for alternative frequencies to a set program (autobest process) or when carrying out a station order or switch-on order process from the memory provided for this purpose .
  • the bit sequence of the known PI code is entered into the memory for the bit sequence 7 together with a likewise known associated offset word, in order then to be compared in each case with the corresponding positions of the shift register.
  • the invention enables rapid synchronization both in the case of frequency switching and in the event of loss of synchronization. There are therefore more identified alternative frequencies, which improves the autobest properties. In particular, it is possible to switch between many alternative frequencies inaudibly. Furthermore, there are shorter mute pauses when performing autobest processes with unknown alternative frequencies and when performing station best and switch-on best processes.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Circuits Of Receivers In General (AREA)
  • Synchronisation In Digital Transmission Systems (AREA)
EP95118045A 1994-11-24 1995-11-16 Méthode pour la synchronisation d'un récepteur RDS et récepteur de radiodiffusion utilisant cette méthode Withdrawn EP0714183A3 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE19944441789 DE4441789C1 (de) 1994-11-24 1994-11-24 Verfahren zur Erkennung von Daten in einem, insbesondere gestörten, RDS-Signal
DE4441789 1994-11-24
DE19539750A DE19539750C2 (de) 1994-11-24 1995-10-26 Verfahren zur Synchronisation eines Rundfunkempfängers und nach diesem Verfahren arbeitender Rundfunkempfänger
DE19539750 1995-10-26

Publications (2)

Publication Number Publication Date
EP0714183A2 true EP0714183A2 (fr) 1996-05-29
EP0714183A3 EP0714183A3 (fr) 1998-08-05

Family

ID=25942247

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95118045A Withdrawn EP0714183A3 (fr) 1994-11-24 1995-11-16 Méthode pour la synchronisation d'un récepteur RDS et récepteur de radiodiffusion utilisant cette méthode

Country Status (1)

Country Link
EP (1) EP0714183A3 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997050201A1 (fr) * 1996-06-25 1997-12-31 Philips Electronics N.V. Procede et systeme de synchronisation dans un train de messages et emetteur et recepteur utilises dans ce systeme
WO1999065182A2 (fr) * 1998-06-08 1999-12-16 Telefonaktiebolaget Lm Ericsson Procede permettant de selectionner un motif de synchronisation a partir d'un signal d'essai

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4611334A (en) * 1984-08-31 1986-09-09 Motorola, Inc. Message capturing radio data system
FR2591834B1 (fr) * 1985-12-13 1988-02-19 Radiotechnique Procede de decodage de donnees radiodiffusees et dispositif de mise en oeuvre
EP0491084A1 (fr) * 1990-12-19 1992-06-24 Siemens Aktiengesellschaft Dispositif pour produire des signaux synchrones pour synchroniser des blocs de télégrammes de données codées en code de blocs avec mots de correction et utilisation

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997050201A1 (fr) * 1996-06-25 1997-12-31 Philips Electronics N.V. Procede et systeme de synchronisation dans un train de messages et emetteur et recepteur utilises dans ce systeme
WO1999065182A2 (fr) * 1998-06-08 1999-12-16 Telefonaktiebolaget Lm Ericsson Procede permettant de selectionner un motif de synchronisation a partir d'un signal d'essai
WO1999065182A3 (fr) * 1998-06-08 2000-02-17 Ericsson Telefon Ab L M Procede permettant de selectionner un motif de synchronisation a partir d'un signal d'essai
US6628737B1 (en) 1998-06-08 2003-09-30 Telefonaktiebolaget Lm Ericsson (Publ) Signal synchronization using synchronization pattern extracted from signal

Also Published As

Publication number Publication date
EP0714183A3 (fr) 1998-08-05

Similar Documents

Publication Publication Date Title
EP0090210B1 (fr) Système pour l'installation automatique d'une communication par ondes courtes à signaux télégraphiques
EP0497116A2 (fr) Récepteur de radiodiffusion avec RDS
DE19539750C2 (de) Verfahren zur Synchronisation eines Rundfunkempfängers und nach diesem Verfahren arbeitender Rundfunkempfänger
EP0666661B1 (fr) Procédé pour identifier le mode de transmission dans un système de transmission numérique à canaux multiples
DE3432848C2 (de) Verfahren zum Übertragen einer digitalen Information
DE3824309A1 (de) Verfahren zur auswertung von in einem datentelegramm digital codiert empfangener verkehrsnachrichten, sowie rundfunkempfaenger
DE3448043A1 (de) Verfahren zum abstimmen eines mobilen rundfunkempfaengers
DE2850733A1 (de) Rundfunkempfaenger, insbesondere ukw- empfaenger, mit einer einrichtung zur programm-direktwahl
WO2000064074A1 (fr) Procede et dispositif pour la synchronisation d'un recepteur radio-mobile avec une structure de trame d'un signal radio
EP0714183A2 (fr) Méthode pour la synchronisation d'un récepteur RDS et récepteur de radiodiffusion utilisant cette méthode
DE60030932T2 (de) Suche des optimalen Abtastzeitpunktes in einem TDMA Paketübertragungssystem
EP0443436B1 (fr) Procédé d'appel sélectif d'un programme de radiodiffusion
EP0433904B1 (fr) Récepteur de radiodiffusion RDS pourvu d'un dispositif de réception préférentielle de programmes ayant le même indicatif national
EP0900432A1 (fr) Procede et recepteur pour la selection geographique de messages codes numeriquement
EP1000516B1 (fr) Procede et dispositif pour commander la reception de paquets de donnees dans une station mobile
DE10133518B4 (de) Verfahren und Vorrichtung zur drahtlosen Übertragung von Sprachdaten
DE4338422C1 (de) Verfahren zur Synchronisation eines RDS-Decoders
EP0652654B1 (fr) Méthode pour la détection de données dans un signal RDS
EP0840230A2 (fr) Dispositif de sélection de mots d'adresse utilisant du décodage de démultiplexage
DE4005413C2 (de) RDS-Rundfunkempfänger mit einer Einrichtung zum beschleunigten Auffinden alternativer Frequenzen
DE19502360C1 (de) Verfahren und Vorrichtung zum schnellen Verfügbarmachen von programmbezogenen Daten im Rundfunkgerät
EP1620978B1 (fr) Procédé et testeur pour déterminer un taux d'erreurs pour un appareil de téléphonie mobile, notamment un USF-BLER
DE2756923A1 (de) Verfahren- und schaltungsanordnung zur nachrichten- und datenuebertragung
EP0171778A2 (fr) Procédé de transmission d'informations au moyen d'une modulation par déplacement de fréquence
DE3817750C2 (de) Funknetz mit stationären und mobilen Funksende- und -empfangsstationen

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): AT CH DE FR GB IT LI NL

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT CH DE FR GB IT LI NL

17P Request for examination filed

Effective date: 19980710

17Q First examination report despatched

Effective date: 20050311

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

Owner name: HARMAN BECKER AUTOMOTIVE SYSTEMS GMBH

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20060307