EP0445027B1 - Verfahren zur Synchronisierung von Sendern in einem Rundfunknetz - Google Patents

Verfahren zur Synchronisierung von Sendern in einem Rundfunknetz Download PDF

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Publication number
EP0445027B1
EP0445027B1 EP91400528A EP91400528A EP0445027B1 EP 0445027 B1 EP0445027 B1 EP 0445027B1 EP 91400528 A EP91400528 A EP 91400528A EP 91400528 A EP91400528 A EP 91400528A EP 0445027 B1 EP0445027 B1 EP 0445027B1
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Prior art keywords
signal
frequency
source signal
digital
digitized
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French (fr)
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EP0445027A1 (de
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Patrice Bourcet
Alain Komly
Michel Seguin
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Telediffusion de France ets Public de Diffusion
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Telediffusion de France ets Public de Diffusion
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04H—BROADCAST COMMUNICATION
    • H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
    • H04H20/65—Arrangements characterised by transmission systems for broadcast
    • H04H20/67—Common-wave systems, i.e. using separate transmitters operating on substantially the same frequency

Definitions

  • the field of the invention is that of methods for synchronizing the transmitters of a broadcasting network, in particular broadcasting, in frequency modulation.
  • the synchronization of two transmitters makes it possible in particular to guarantee the identity of the signals delivered by each transmitter at a constant level and at a ready delay.
  • the invention relates to a method of synchronizing a plurality of transmitters in a broadcasting network comprising a production site of a program linked by transmission links to said transmitters remote from the production site, the production site transmitting to each transmitter a baseband source signal corresponding to the program and each transmitter broadcasting a final signal in frequency modulation originating from a plurality of processing steps of the source signal.
  • the objective of the invention is to overcome the various drawbacks of the state of the art and in particular to produce a network of transmitters in synchronous frequency modulation which respects the usual structure of a broadcasting network, which allows adjustment simple and precise phasing of synchronous signals at critical points in the areas served, which uses equipment compatible with current equipment indifferently authorizing the equipment and operation of the broadcasting network in synchronous or non-synchronous mode, and in which the transmitters simultaneously broadcast a final signal on the same carrier frequency.
  • the identity of the signals received by the transmitters is guaranteed to within a transmission delay. Thanks to the fact that a predetermined delay is applied in the diffusion of the final signal at the level of each transmitter, it is possible to phase the signals transmitted at the level of the critical zones.
  • the structure of a traditional broadcasting network essentially comprises a production site 10 connected by a transmission network 20 to a plurality of transmitters 30 remote from the production site, of which four transmitters have been shown in this figure.
  • the transmission network 20 establishes the links necessary for the distribution of a baseband source signal to be transmitted corresponding to a program, from the production site 10 of this signal to each transmission site 30 of a final signal intended for listeners.
  • Each transmitter 30 covers a respective transmission zone, not shown, defined by the directivity diagram of its associated antenna.
  • the emission zones partially overlap in critical zones 35 where the fields have very little different average levels.
  • the production site 10 mainly comprises an analog-to-digital converter 15 for digitizing the baseband source signal available for example in analog form on a recording medium 11 and corresponding to the program to be transmitted.
  • the digitization of the baseband source signal is done by sampling at a determined sampling frequency Fe, for example at a sampling frequency of 32 kHz.
  • the baseband source signal is a stereophonic signal consisting of a left voice and a right voice, the analog-to-digital conversion 15 delivering two series of binary values, respectively left voice and right voice, each series comprising Fe values of 16 binary elements per second.
  • the digital series obtained at the output of the analog-to-digital conversion 15 are framed by alternating the left voice and the right voice by example in accordance with the "EBU / AES" standard.
  • the framing step 17 carried out after the analog to digital conversion step 15 of the baseband signal makes it possible to constitute a digital serial signal to be transmitted SNE conforming to the "EBU / AES" standard.
  • the signal SNE also includes signals or service data 12 specific to the transmission network, this being made possible by the format of the frame.
  • the SSP signal constitutes a synchronization signal at the rate of 1 kHz, transmitted by means of the "user" binary element provided in the format of the "EBU / AES" standard.
  • This SSP signal is generated by a subcarrier synchronization signal generator 16.
  • the analog-digital converter 15, the framing device 17 and the synchronization signal generator 16 are paced at the same frequency and in synchronism by a clock 18 generating a signal of frequency Fe, hereinafter called sampling frequency Fe.
  • the broadcasting network is constructed using digital transmission links 20 as shown in FIG. 3.
  • the purpose of these digital transmission links is to route the signal SNE from the production site 10 to each of the transmitters 30 and to guarantee reception of the same digital signal.
  • any type of known digital transmission medium can be used, namely an optical fiber, an electric cable, the radio link or the satellite link.
  • the Hertzian beam it suffices to use a framing, in the context of a transmission known to those skilled in the art, of the digital serial signal SNE at the head of the transmission network for directly attack a such a beam via a transmitter 22 and an antenna 23.
  • the broadcast signal is received on the reception side of the digital transmission link by an antenna 24 coupled to a receiver 25.
  • a star network is obtained as shown in FIG. 1.
  • the signal to be transmitted is transmitted by successive hops from the production site 10 to the first transmission site then from this site to the second emission site, and so on.
  • an online network is obtained.
  • a regenerator 27 is connected to a re-emitter 28 associated with an antenna 29 so as to be able to make as many successive hops as necessary without degrading the signal to be transmitted.
  • a broadcasting network can present a mixture of the two configurations mentioned above, but, in all cases, the broadcasting network according to the invention has only one production site 10 or is digitized only once. the baseband source signal.
  • the devices used to establish the digital transmission link 20 are distributed between the production site 10 and the transmitting sites 30. As visible in FIG. 3, a transmitter 30 can receive the equipment 27, 28, 29 necessary for the retransmission of the signal SNE in the case of an online transmission.
  • each transmitter 30 comprises according to the invention a synchronizable modulator coder 40, receiving as input the signal SNE.
  • the synchronizable modulator coder 40 delivers, following a plurality of steps for processing the signal SNE, a signal final analog in frequency modulation, at a final emission frequency identical for each transmitter and situated for example between 88 and 108 MHz.
  • the final analog signal is finally amplified by a power amplifier 50 delivering the power necessary for a transmitting antenna 60 in accordance with the specifications of the transmission site considered. It will be understood that synchronization only applies in the case where several transmitters operate simultaneously on the same transmission frequency.
  • each transmitter 30 After transmission by the production site 10 of the digitized baseband source signal SNE, each transmitter 30 nominally receives the same signal SNE. The difference in transmission time from one transmitting site to another is likely to affect the reception of the SNE signal by each transmitter with a different delay. However, apart from a delay, the SNE signals received by the transmitters 30 are identical due to the digital transmission. Furthermore, in the case of a stereophonic baseband source signal, the phase of the SSP subcarrier synchronization signal introduced into the SNE signal is identical from one transmission site to the other upon reception of the signal. SNE signal.
  • the signal SNE received by the transmitter 30 is transmitted to the synchronizable modulator coder 40.
  • the synchronization of the coder-modulator 40 consists in being able to program a "transmission delay" of the final signal, this "transmission delay” compensating for the "delay of reception "of the signal SNE at each transmitting site 30 and the" delay of reception "of the signal transmitted at the level of the critical zone.
  • the modulator coder 40 comprises a digital part 40A where digital processing steps are carried out on the signal SNE for supplying a servo signal and an analog frequency modulation signal from an intermediate frequency carrier Fi for example 10.7 MHz, and an analog part 40B receiving said analog frequency modulation signal and said servo signal where analog processing steps on said analog signal to provide the final analog signal to be broadcast in frequency modulation on the final carrier tuned to the final frequency.
  • FIG. 5 schematically represents the different stages of digital processing while FIG. 6 schematically represents the various stages of analog processing.
  • the digital signal SNE in the form of a serial transmission of bits is received by a frame receiver 400 conforming to the "EBU / AES" standard.
  • the frame receiver 400 separates each right and left voice, in the signal SNE, to deliver in parallel two series of digital values VDN, VGN corresponding respectively to the right voice and to the left voice, each value being coded on 16 bits.
  • the frame receiver 400 also delivers the sub-carrier synchronization signal SSP.
  • a timing signal representative of the sampling frequency Fe is recovered on reception of the signal SNE by the frame receiver, by counting and detection of the received bits.
  • the SSP signal constitutes, as already mentioned above, a synchronization signal at the rate of 1 kHz.
  • the frame receiver 400 being designed to operate at a frequency Fe whose nominal value is fixed at 32 kHz for example, a phase locked loop controlled by the timing signal is used to provide the frame receiver with a timing signal representing the smoothed sampling frequency Fe exhibiting a short-term stability greater than the recovered frequency Fe and for synchronizing all the processing operations on this smoothed frequency Fe.
  • the phase-locked loop consists of a comparator phase 431 receiving at a first input the timing signal, a loop filter 432 connected at input to the output of the phase comparator and intended to ensure the stability of the loop, a temperature compensated oscillator 433 oscillating at a reference frequency of 40.96 MHz and connected at the input to the output of the loop filter and a divider of the reference frequency 440 connected at the input to the output of the temperature compensated oscillator.
  • the divider 440 is connected to the frame receiver 400 as well as to a second input of the phase comparator 431, the smoothed frequency Fe delivered by the divider 440 corresponding to the division by 1280 of the reference frequency supplied by the controlled oscillator.
  • the smoothed frequency Fe therefore has a nominal value of 32 kHz corresponding to the nominal value of the sampling frequency Fe of the baseband signal.
  • the digital series VGN, VDN originating from the frame receiver 400 must be represented according to the invention in the form of a stereo digital multiplex authorizing the voltage / frequency conversion. Furthermore, the digital series VGN, VDN originating from the frame receiver 400 represent signals digitized at the frequency Fe of 32 kHz. Sampled in time, these signals are of the periodic frequency type and therefore occupy the entire frequency spectrum in the form of replicas around the multiples of the sampling frequency Fe (64 kHz, 96 kHz, 128 kHz, etc.). ).
  • a series of oversampling steps 401, 403 are performed on the VGN, VDN digital series. Each oversampling step makes it possible to reject unwanted replicas outside the useful part of the spectrum reserved for the constitution of the multiplex .
  • the oversampling of the VGN, VDN digital series consists in reconstructing the missing samples between the known samples for each of the right and left voices.
  • a transverse low pass filter FIR
  • This operation is done without gain in precision since the original description of the baseband signal is sufficient for a digital / analog converter to be able to reconstruct this signal perfectly. It will however be noted that for a constant computing power, it is necessary to make a compromise between the quality of the oversampling carried out, ie the number of coefficients of the transversal filter used, and the oversampling factor.
  • each sample at the output of the filter is calculated by convolution of the non-zero input samples with 1 / n of the coefficients of the transversal filter, n being the multiplicative factor of oversampling.
  • the coefficients of the transversal filters used were calculated using a computer according to the REMETZ algorithm published in "The Technical and Scientific Collection of Telecommunications - Digital signal processing" by Mr. BELLANGER - 3rd edition MASSON.
  • a second oversampling step 403 is carried out by a factor P2 on each of the two digital series as shown in FIG. 5.
  • This processing 403 is carried out by a second microprocessor circuit specialized in signal processing identical to the previous one and programmed to perform oversampling by a factor P2 equal this time to 4.
  • a stereo digital multiplex 404 consists of performing the operation: (VGN ′ + VDN ′) / 2 + ⁇ (VGN ′ - VDN ′) (/ 2 ⁇ x P + Q where P represents a carrier frequency at 38 kHz and Q a pilot frequency at 19 kHz. This operation is performed on each sample of the VGN ′, VDN ′ series at the rate of P1 x P2 x Fe, ie 256 kHz.
  • Synchronization between these different processing steps is carried out by the fact that in each step the corresponding calculation is carried out in a time less than the time allocated to make this calculation, so that at the level of the last step we can have in permanence of the right number of samples to be delivered per unit of time.
  • a frequency of 19 kHz or 38 kHz is synthesized as is known to those skilled in the art.
  • the SSP signal whose recurrence of 1 kHz makes it possible to periodically control, at each complete passage of the PROM, for the two reading increments, that the digital synthesis begins at the same address in the PROM memory and at the same instant for each transmitter. For example, every millisecond, on reception of signal SSP, the zero address of the PROM memory is imposed as a summary reference.
  • the second microprocessor circuit is programmed to synthesize the subcarrier P and pilot Q signals thanks to its internal PROM memory.
  • the digital multiplex obtained at the output of the multiplexing step 404 is identical from one transmitting site 30 to another.
  • the muliplex obtained at the output of these processing steps is in the form of a series of sixteen-bit words delivered at the rate Fh.
  • FIG. 7 represents in the form of a chronogram the rhythms of calculations in the different processing stages.
  • the sample clock signal or interrupt signal gives 32,000 synchronization tops every second, this signal corresponding to the sampling frequency Fe.
  • two samples right voice, left voice, represented by the reference n (g + d) are taken care of in step 401 of oversampling by two.
  • two samples right voice, and two left voice samples are produced corresponding to the references ng1, ng2, nd1, nd2.
  • the samples ng1 and nd1 are then used in the second oversampling step 403 and in the step of constituting the multiplex 404 to provide the samples of the multiplex represented by the reference ng1 + nd1 of index 1, 2, 3, 4 corresponding to the four periods of serial transmission of oversampling by four.
  • Each sample ng1 + nd1 of index i from 1 to 4 is used in the step of oversampling by eight 405 to deliver eight corresponding samples represented by blocks 8, 16, 24, 32.
  • the samples represented by blocks 40, 48 , 56, 64 are calculated in the same way by oversampling by thirty two from samples ng2 and nd2.
  • transmitter 30 As described below. Referring to Figure 8, there is shown a diagram of the propagation times of a source signal from the production site to critical areas. It is considered in the example that the production site is placed at the level of the transmitter 302 and the broadcasting network consists of the three transmitters 301, 302, 303 of FIG. 1. This configuration is given by way of example not limiting.
  • t0 represents the time reference at the time of the production of the source signal.
  • t1 represents the time of arrival with respect to the time t0 of the signals at the level of the area 352.
  • t2 represents the time of arrival with respect to the time t0 of the signals at the level of the area 351.
  • T t1 represents the propagation time necessary for the transmission of the source signal from the production site 10 (transmitter site 302) to the transmitter site 301.
  • T t3 represents the propagation time necessary for the transmission of the source signal from the production site 10 to the emitting site 303.
  • the propagation time necessary for the transmission of the source signal from the production site 10 to the transmitting site 302 is negligible by construction of the network. These propagation times are calculated from the determination of the relative geographic positions of the emission sites with respect to the production site and as a function of the speed of transmission of the signal in the transmission medium 20. In the case of a medium transmission time such as the Hertzian beam, the transmission time is approximately 10/3 microseconds / kilometer.
  • T d1 represents the propagation time necessary for the diffusion of the final signal in frequency modulation from the transmitting site 301 to the critical zone 351.
  • T ′ d2 represents the propagation time necessary for the diffusion of the final frequency modulation signal from the transmitting site 302 to the critical zone 351.
  • T d2 represents the propagation time necessary for the diffusion of the final frequency modulation signal from the transmitting site 302 to the critical zone 352.
  • T d3 represents the propagation time necessary for the diffusion of the modulation signal frequency from the transmitting site 303 to the critical zone 35 2.
  • specific delays are applied for the broadcasting of the frequency modulation signal at each transmitter connected to the production site 10.
  • the application of these specific delays is carried out as follows.
  • a diffusion delay corresponding to a guard delay R3 is applied to a first transmitter, for example the transmitter 303, so that, as shown in FIG. 8 in correspondence with the transmitter 303, the propagation time of the source signal from the production site 10 via the transmitter 303 to the critical zone 352 is equal to T t3 + R3 + T d3 .
  • the signals transmitted by the transmitters 302 and 303 must be in phase.
  • a synchronizer 420 receiving the series of binary words constituting the multiplex, stores them temporarily and restores them in their order of arrival, at the frequency Fh.
  • the temporary storage of binary words in the synchronizer 420 amounts to delaying at the level of an emitting site 30 the emission of the final signal which will be formed from this series of binary words.
  • the synchronizer 420 may for example consist of a memory with dual access in read and write, the time difference between the writing of a data item in memory and its reading corresponding to a delay whose precision is 1 / Fh.
  • it is easy to program a delay 430 which can go up to a millisecond, for example if the size of the dual-access memory used allows the memorization of 2048 words of 16 binary elements.
  • the synchronizer 420 is controlled at output at the frequency Fh generated by the phase locked loop 431, 432, 433, 440. This frequency corresponds to the overall frequency of arrival of the binary words from the oversampling 405.
  • the digital multiplex delayed in step 420 is transmitted at frequency Fh to a digital modulator 421.
  • the digital modulator 421 is a synthesizer using a memory of the read only memory type containing N (65536) digital values corresponding to the samples of a complete period of a sinusoid, each value being coded on 16 binary elements.
  • the carrier frequency Fp generated by the frequency synthesizer is directly dependent on the address increment N0 with which the memory is read.
  • each value of the series of values constituting the multiplex at the output of the synchronizer 420 is added modulo N to the increment N0 to constitute a new increment.
  • the value of the new increment is then added modulo N to the current address of the memory.
  • a scaling factor of the voltage-frequency conversion is obtained by connecting, for example, thirteen most significant binary elements of each binary word of the series of binary words constituting the multiplex to the thirteen least significant binary elements of the read address word. memory containing the sinusoid samples.
  • the frequency increment of the synthesizer being determined by the ratio Fh / N, that is to say 31.25 Hz, this results in a maximum deviation of the carrier frequency Fp, before clipping of 256 kHz (31.25 x 213), that is to say 128 kHz deviation on either side of this carrier frequency. This gives a margin of approximately 4.6 dB compared to the maximum normalized deviation of ⁇ 75 kHz.
  • the digital signal representing the carrier frequency Fp modulated at the output of the digital modulator 421 is then multiplied with a frequency Ft to obtain a frequency transposition of the modulation.
  • the quantization precision on sixteen binary elements of each binary word coming from the digital modulator 421 is no longer useful and consequently the multiplication with the frequency Ft is limited to the twelve most significant binary elements of each of these words.
  • the values chosen for the frequencies Fp and Ft are respectively 460 kHz and 10.24 MHz.
  • the words of twelve binary elements resulting from the multiplication are delivered at the frequency Ft and converted to a double frequency by a digital analog converter 423 adapted to convert words of twelve binary elements.
  • the frequencies Fh, Ft and 2Ft are obtained at the output of the divider 440 of the phase locked loop synchronized on the frequency Fe.
  • all these frequencies are synchronous with one another and with Fe.
  • a control signal is also obtained according to the same principle by division at the level of the phase lock loop on Fe, this control signal being intended to synchronize the analog transposition to the final frequency of the signal to be transmitted.
  • the analog signal at the intermediate frequency and the servo signal are transmitted to the analog part 40B of the synchronizable modulator coder according to the invention.
  • the analog signal from digital to analog conversion is filtered 450 by a bandpass filter centered on the frequency of 10.7 MHz so as to eliminate all unnecessary image frequencies.
  • the transposition 451 is carried out at the final carrier frequency f in a conventional analog manner.
  • a phase locked loop 455, 456, 457, 458 is implemented, slaving a controlled oscillator 457 which is used as a reference to obtain a local conversion frequency 454.
  • the loop is locked to the servo signal from the divider 440, this servo signal itself being locked in phase on the signal sampling frequency Fe.
  • the signal from the transposition to the final frequency is finally filtered by a bandpass filter centered on the final transmission frequency which is between 88 and 108 MHz.

Claims (8)

  1. Verfahren zur Synchronisierung von Sendern in einem Sendenetz, insbesondere einem Rundfunksendenetz, das einen Produktionsort (10) eines Programmes aufweist, der durch Übertragungsverbindungen (20, 25) mit einer Vielzahl von Sendern (30) verbunden ist, die vom Produktionsort entfernt sind, wobei der Produktionsort jedem Sender ein dem Programm entsprechendes Quellensignalbasisband übermittelt und jeder Sender ein Endsignal in Frequenzmodulation desselben Sinussträgers ausstrahlt, wobei das Endsignal aus einer Vielzahl von Schritten zur Verarbeitung des Quellensignals hervorgegangen ist, Verfahren, dadurch gekennzeichnet, daß
    - das Quellensignal durch Abtastung mit einer vorbestimmten Abtastfrequenz digital konvertiert wird, um den Sendern ein digitales Quellensignal zu übermitteln,
    - die Schritte der Verarbeitung des digitalen Quellensignals mit der genannten Abtastfrequenz synchronisiert werden und
    - in einem der Schritte der Verarbeitung des Quellensignals eine vorbestimmte Verzögerung in der Ausstrahlung des Endsignals vorgenommen wird.
  2. Verfahren nach Patentanspruch 1, dadurch gekennzeichnet, daß die Schritte der Verarbeitung des digitalen Quellensignals einen Synchronisierschritt (420) enthalten, die darin besteht, das digitale Quellensignal vorübergehend zu speichern, um die Ausführung eines folgenden Schrittes der Signalverarbeitung um eine vorbestimmte Zeitdauer zu verzögern, und einen Schritt zur digitalen Modulation (421) des digitalen Quellensignals, um ein synthetisiertes frequenzmoduliertes Signal zu liefern.
  3. Verfahren nach Patentanspruch 1 oder 2, dadurch gekennzeichnet, daß eine Phasenverriegelungsschleife verwendet wird, die durch die aus dem übermittelten digitalen Quellensignal rückgewonnene Abtastfrequenz gesteuert wird, um eine geglättete Frequenz zu liefern, durch die die Schritte der Verarbeitung des digitalen Quellensignals synchronisiert werden.
  4. Verfahren nach Patentanspruch 1, in dem das Quellensignalbasisband ein Stereophoniesignal ist, dadurch gekennzeichnet, daß die Schritte der Verarbeitung des digitalen Quellensignals Schritte (401, 402, 403, 404) zur Kodierung der beiden Kanäle des digitalen Quellensignals zur Ausgabe eines digitalen Multiplexes enthalten, der in einer Form vorliegt, der eine Spannungs/Frequenz-Konvertierung ermöglicht.
  5. Verfahren nach Patentanspruch 4, dadurch gekennzeichnet, daß der digitale Multiplex durch Kombination der beiden Kanäle des digitalen Quellensignals mit einem durch direkte digitale Synthese (410, 411) erzeugten Hilfsträgersignal und Pilotton erhalten wird.
  6. Verfahren nach Patentanspruch 5, dadurch gekennzeichnet, daß die direkte digitale Synthese des Hilfsträgersignals und des Pilottons mit einem Hilfsträgersynchronisiersignal synchronisiert wird, das mit dem digitalen Quellensignalbasisband übertragen wird.
  7. Verfahren nach Patentanspruch 2, dadurch gekennzeichnet, daß die Schritte der Signalverarbeitung außerdem enthalten:
    - einen Schritt zur Digital-/Analog-Wandlung (423) des synthetisierten frequenzmodulierten Signals, um dieselbe Frequenzmodulation in analoger Form zu erhalten, und
    - einen Schritt zur analogen Umsetzung (451) des vorangehenden analogen Signals, um eine identische Frequenzmodulation bei allen Sendern bei einer Endsendefrequenz zu erreichen.
  8. Verfahren nach Patentanspruch 7, dadurch gekennzeichnet, daß die Schritte zur analogen Umsetzung (451) durch ein Regelsignal synchronisiert wird, das durch die genannte Phasenverriegelungsschaltung erzeugt wird.
EP91400528A 1990-03-02 1991-02-27 Verfahren zur Synchronisierung von Sendern in einem Rundfunknetz Expired - Lifetime EP0445027B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9002629A FR2659181B1 (fr) 1990-03-02 1990-03-02 Procede de synchronisation d'emetteurs dans un reseau de diffusion radiophonique.
FR9002629 1990-03-02

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EP0445027A1 EP0445027A1 (de) 1991-09-04
EP0445027B1 true EP0445027B1 (de) 1994-07-20

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US (1) US5216717A (de)
EP (1) EP0445027B1 (de)
DE (1) DE69102906T2 (de)
ES (1) ES2056592T3 (de)
FR (1) FR2659181B1 (de)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5604768A (en) * 1992-01-09 1997-02-18 Cellnet Data Systems, Inc. Frequency synchronized bidirectional radio system
US5377232A (en) * 1992-01-09 1994-12-27 Cellnet Data Systems, Inc. Frequency synchronized bidirectional radio system
FR2690593B1 (fr) * 1992-04-22 1995-06-30 Telediffusion Fse Procede de synchronisation d'au moins une composante d'un signal multiplex.
WO1994022275A1 (fr) * 1993-03-18 1994-09-29 Luigi Capasso Systeme multi-microphones/emetteurs sans fil a porteuse commune
DE69535958D1 (de) * 1994-09-12 2009-07-02 Sony Corp Übertragungsnetz, verfahren und sender zur gleichzeitigen übertragung
US5842134A (en) * 1995-09-28 1998-11-24 Ericsson Inc. Auto-alignment of clear voice and low speed digital data signals in a simulcast system
FR2760920B1 (fr) * 1997-03-12 2000-08-04 Sagem Procede de transmission de donnees entre des moyens de traitement de donnees et un reseau de radiocommunication et module et terminal mobile pour la mise en oeuvre du procede
DE19737758A1 (de) * 1997-08-29 1999-03-04 Bosch Gmbh Robert Verfahren zum Einstellen der Sendeträgerfrequenz in einer Teilnehmerstation eines Punkt-zu-Mehrpunkt Funkübertragungssystem
US6185305B1 (en) * 1998-05-04 2001-02-06 Motorola, Inc. Method and system for broadcasting digital audio to a radio
US6349215B1 (en) * 1999-05-21 2002-02-19 Warren L. Braun Synchronization of broadcast facilities via microwave tone
US6349214B1 (en) * 1999-05-21 2002-02-19 Warren L. Braun Synchronization of broadcast facilities via satellite
KR100370216B1 (ko) * 2000-08-18 2003-01-29 삼성전자 주식회사 Ｅ-쿠폰 데이터 방송을 이용한 광고 시스템 및 방법
US6563893B2 (en) * 2001-05-17 2003-05-13 Ut-Battelle, Llc Carrier-frequency synchronization system for improved amplitude modulation and television broadcast reception
US7587017B2 (en) * 2001-05-17 2009-09-08 Ut-Battelle, Llc Carrier phase synchronization system for improved amplitude modulation and television broadcast reception
US7072431B2 (en) * 2002-10-30 2006-07-04 Visteon Global Technologies, Inc. Clock timing recovery using arbitrary sampling frequency
US7533285B2 (en) * 2004-04-22 2009-05-12 Hewlett-Packard Development Company, L.P. Synchronizing link delay measurement over serial links
JP4469758B2 (ja) * 2005-07-04 2010-05-26 パナソニック株式会社 音声処理装置
JP5217999B2 (ja) * 2008-12-12 2013-06-19 沖電気工業株式会社 伝搬遅延時間調整方法、伝搬遅延時間調整システム、伝搬遅延時間調整装置、伝搬遅延時間調整プログラム及びノード装置

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1109524A (en) * 1977-07-15 1981-09-22 James L. Osborn Simulcast transmission system
US4317220A (en) * 1979-02-05 1982-02-23 Andre Martin Simulcast transmission system
DE3020176A1 (de) * 1980-05-28 1981-12-03 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Verfahren und anordnung zum zeitgleichen aussenden von nachrichten ueber mehrere gleichwellensender
US4608699A (en) * 1982-12-27 1986-08-26 Motorola, Inc. Simulcast transmission system
DE3511430A1 (de) * 1985-03-29 1986-10-02 Philips Patentverwaltung Gmbh, 2000 Hamburg Verfahren zur synchronisierung der empfangseinrichtungen in einem digitalen multiplex-uebertragungssystem
DE3642982A1 (de) * 1986-12-17 1988-06-30 Thomson Brandt Gmbh System zur uebertragung
US5038402A (en) * 1988-12-06 1991-08-06 General Instrument Corporation Apparatus and method for providing digital audio in the FM broadcast band
US4972410A (en) * 1989-07-20 1990-11-20 Electrocom Automation, Inc. Method and apparatus for controlling signal coherency in simulcast systems

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DE69102906D1 (de) 1994-08-25
FR2659181A1 (fr) 1991-09-06
US5216717A (en) 1993-06-01
EP0445027A1 (de) 1991-09-04
ES2056592T3 (es) 1994-10-01
FR2659181B1 (fr) 1994-01-14
DE69102906T2 (de) 1995-03-02

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