Method for fast recovery of timing and device produced according to this method

• Main Author: JEAN-FRANCOIS RENE CORNET
• Format: Patent
• Language: English; French
• Published: 26.10.1984
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

Method for fast recovery of timing and device produced according to this method. The recovery of timing in a receiver receiving data in packets is achieved by means of a tuned circuit 15, 16 which receives the pulses of transitions and whose oscillations are transmitted to a comparator 3 which provides the timing information. To prevent the phenomena which bring about loss of timing information and which are favoured by the high value of the quality factor of the tuned circuit, the method according to the invention consists in lowering this quality factor during the time interval between two consecutive packets and in restoring it linearly to its nominal value from the start of reception of the following packet. Producing a device according to this method consists in connecting up across the terminals of the tuned circuit 15, 16 a fixed damping resistor 28 in series with a variable damping resistor stationed at the output of a damping control circuit 4 whose input receives a control pulse generated at the end of reception of each packet. Application to the reception of data transmitted in packets. PROCEDE DE RECUPERATION RAPIDE DE RYTHME ET DISPOSITIF REALISE SUIVANT CE PROCEDE.LA RECUPERATION DE RYTHME DANS UN RECEPTEUR RECEVANT DES DONNEES PAR PAQUETS EST EFFECTUEE AU MOYEN D'UN CIRCUIT ACCORDE 15, 16 QUI RECOIT LES IMPULSIONS DE TRANSITIONS ET DONT LES OSCILLATIONS SONT TRANSMISES A UN COMPARATEUR 3 QUI FOURNIT L'INFORMATION DE RYTHME. POUR PREVENIR LES PHENOMENES ENTRAINANT LA PERTE D'INFORMATION DE RYTHME ET FAVORISES PAR LA VALEUR ELEVEE DU COEFFICIENT DE SURTENSION DU CIRCUIT ACCORDE, LE PROCEDE, SELON L'INVENTION, CONSISTE A ABAISSER CE COEFFICIENT DE SURTENSION PENDANT L'INTERVALLE DE TEMPS ENTRE DEUX PAQUETS CONSECUTIFS ET A LE RAMENER LINEAIREMENT A SA VALEUR NOMINALE DES LE DEBUT DE RECEPTION DU PAQUET SUIVANT. LA REALISATION D'UN DISPOSITIF, SELON CE PROCEDE, CONSISTE A MONTER AUX BORNES DU CIRCUIT ACCORDE 15, 16 UNE RESISTANCE D'AMORTISSEMENT FIXE 28 EN SERIE AVEC UNE RESISTANCE D'AMORTISSEMENT VARIABLE APPARAISSANT EN SORTIE D'UN CIRCUIT DE COMMANDE D'AMORTISSEMENT 4 DONT L'ENTRE RECOIT UNE IMPULSION DE COMMANDE ENGENDREE EN FIN DE RECEPTION DE CHAQUE PAQUET.APPLICATION A LA RECEPTION DE DONNEES TRANSMISES PAR PAQUETS.