EP1131927A1 - Procede de regler un emetteur a une puissance d'emission - Google Patents

Procede de regler un emetteur a une puissance d'emission

Info

Publication number
EP1131927A1
EP1131927A1 EP99960905A EP99960905A EP1131927A1 EP 1131927 A1 EP1131927 A1 EP 1131927A1 EP 99960905 A EP99960905 A EP 99960905A EP 99960905 A EP99960905 A EP 99960905A EP 1131927 A1 EP1131927 A1 EP 1131927A1
Authority
EP
European Patent Office
Prior art keywords
radiation power
signal
binary
transmission
participant
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Withdrawn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
EP99960905A
Other languages
German (de)
English (en)
Inventor
Johannes Bozenhardt
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.)
Siemens AG
Original Assignee
Siemens AG
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 DE1998152749 external-priority patent/DE19852749A1/de
Priority claimed from DE1998155225 external-priority patent/DE19855225A1/de
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP1131927A1 publication Critical patent/EP1131927A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/38—Synchronous or start-stop systems, e.g. for Baudot code
    • H04L25/40—Transmitting circuits; Receiving circuits
    • H04L25/49—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems
    • H04L25/4917—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems using multilevel codes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/38—Synchronous or start-stop systems, e.g. for Baudot code
    • H04L25/40—Transmitting circuits; Receiving circuits
    • H04L25/49—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems
    • H04L25/4917—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems using multilevel codes
    • H04L25/4919—Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems using multilevel codes using balanced multilevel codes

Definitions

  • the invention relates to a method for setting a radiation power in a transmitter of a subscriber of an optical data transmission system, wherein a transmission signal can be generated by the subscriber from a binary signal and can be transmitted by this subscriber to a further subscriber of the optical data transmission system, and wherein the transmission signal comprises light pulses which include a radiation power corresponding to bit information "0" or a bit information "1" can be transmitted.
  • Bit information "0" of a binary signal to be transmitted is usually characterized by a first low radiation power and bit information "1" by a second high radiation power.
  • the first and second radiation powers are dimensioned such that a receiver can still reliably decode the corresponding bit information "0" and "1".
  • the bit information "1" is to be transmitted over a longer transmission phase, which means that, in particular in the event that a low-frequency binary signal is to be transmitted over an optical path, the probability is very high that a sequence of light pulses must be transmitted with a high radiation power.
  • This can mean that the transmitter is overloaded, which has a disadvantageous effect on its service life, the service life usually being a period of time after which the originally maximum adjustable radiation power has dropped to fifty percent of this radiation power.
  • a participant of an optical transmission system in particular a participant with light emitting diodes of high transmission power, is that no special protective measures are provided to classify into a so-called laser protection class II, since the average radiation power exceeds a predefinable limit value in an observation interval (time interval) proposed in this standard.
  • special security measures with regard to eye protection are required for the use of such subscribers in an optical data transmission system.
  • EP 0 460 626 is a subscriber of an optical
  • Known data transmission system which is connected to further participants connected in a ring-shaped optical data transmission line, the participants being each provided with optical transmitters and receivers. Measures to adjust the radiation power of the transmitter are not provided.
  • the present invention has for its object to provide a method of the type mentioned, which allows easy adjustment of the radiation power of the transmitter.
  • a participant is to be created according to the preamble of claim 6, in which the radiation power of the transmitter is easily adjustable.
  • this object is achieved by the measures specified in the characterizing part of claim 1, with regard to the participant by the measures specified in the characterizing part of claim 6.
  • the useful life (lifespan) of the transmitter is increased by setting the radiant power to a predeterminable first limit value, which is smaller than the power integral in an unmodulated transmission.
  • the lifespan of the transmitter is essentially determined by the sum of the radiation power in this period.
  • the usable cable length in the system can be increased for a given service life of the transmitter by z.
  • the radiation power is set to a predeterminable second limit value, which corresponds to the maximum radiation power for which the manufacturer specifies the service life; because the minimum radiation power that a receiver needs to still reliably recognize bit information is usually known from data sheets or from a suitable measurement.
  • the respective attenuation of the plug and the cable is usually known.
  • the peak value of the radiation power can be increased for a given service life of the transmitter by setting the limit value accordingly, without exceeding the technical limit values.
  • the maximum distance to be bridged can thus be increased.
  • a simple amplitude modulation of the binary information of the binary signal generates a transmission signal in such a way that the average radiation power does not exceed the predefinable limit value.
  • Figures 1 and 2 show the time course of a binary signal and modulation signals and Figure 3 is a block diagram of a transmitter.
  • la denotes a binary signal provided with a bit clock 2, having bit information "0" and bit information "1".
  • a subscriber of an optical data transmission system From the binary information of the binary signal la, a subscriber of an optical data transmission system generates an amplitude-modulated transmission signal 4 which comprises light pulses which are to be transmitted to a further subscriber of the data transmission system with a radiation power corresponding to the bit information "0" and the bit information "1".
  • the transmission signal 4 comprises four radiation power levels 0%, 50%, 100% and 150%, based on a maximum value of a radiation power in the case of an unmodulated light transmission of the sending subscriber.
  • bit information "1" is assigned to a group of radiation powers equal to or greater than 50%, the bit information "0" to a group of radiation powers less than 50%.
  • the receiving subscriber is designed in such a way that the subscriber caught radiation power can decode the bit information "0" and "1".
  • the average radiation power in this unmodulated light transmission of bit information “1” over a period of one bit clock 2 comprises eight radiation units.
  • the modulated transmission signal 4 has a modulation clock 3, which corresponds to a four-fold bit clock 2, whereby a time interval Zi comprises twenty modulation clocks 3.
  • the bit information is "0", no light is transmitted and the radiant power is zero.
  • the binary signal la changes its level from “0" to "1” and up to a time tOl in the case of an unmodulated data transmission up to this time tOl light would be transmitted with two radiation units.
  • the radiation power of the transmission signal 4 during this period is one and a half times the unmodulated comparison signal Ib, as a result of which light with an increased radiation power, namely with three radiation units, is transmitted. This excessive radiation power produces an improved contrast between dark and light in the receiving subscriber, which simplifies decoding of the transmitted signal with regard to the bit information.
  • the radiation power is reduced by one unit, by the radiation power of the transmission signal 4 corresponds to that of the comparison signal lb.
  • This radiation power remains constant up to a point in time t03. Since a change in level from "1" to "0" is provided in the binary signal la at a time t1, the radiation power of the transmission signal 4 during the modulation clock 3 is in turn changed in the period between the time t03 and tl to achieve a good light / dark contrast increased one and a half times the radiant power of the comparison signal Ib. Up to the time t1, i.e.
  • the transmission signal 4 transmits light with ten radiation units to a subscriber, ie light with two radiation units is transmitted more than with an unmodulated light transmission, because the comparison signal 1b transmits light with eight beams - units.
  • the predetermined limit of twenty-eight radiation units is not exceeded during the time interval Z10 (8, 10).
  • the bit information "0" is to be transmitted between the time t1 and a time t2, as a result of which the sum of the radiation power of the transmission signal 4 remains constant at ten radiation units during the time interval Z20 (8, 10).
  • a time interval Z30 (16, 20) the sum of the radiation power of the transmission signal 4 increases to twenty radiation units, since ten radiation units are provided in a period between the time t2 and a time t3.
  • the sum of the radiation power remains constant in a time interval Z40 (16, 20) up to a time t4, since in a period between the time t3 and t4, however, no light is transmitted.
  • the radiation power of the transmission signal 4 initially again shows one and a half times to achieve a good light / dark contrast the radiation power of the unmodulated comparison signal lb.
  • the radiation power of the transmission signal 4 corresponds to the simple, between the time t42 and a time t43 half and between the time t43 and a time t5 the simple radiation power of the unmodulated comparison signal Ib.
  • the sending subscriber generates the send signal 4 in the following time intervals in such a way that the average radiation power does not exceed the predetermined limit value of twenty-eight radiation units.
  • the radiation power of the unmodulated comparison signal Ib increases, reaches the predetermined limit value at a time t62 in a time interval Z62 (28, 25) and finally exceeds the limit value at a next time t63.
  • the radiation power of the unmodulated comparison signal Ib comprises thirty radiation units.
  • the transmission signal 4 comprises twenty-four radiation units in the time interval Z61 (26, 24), twenty-five at time t62 in the time interval Z62 (28, 25), twenty-seven at time t63 in the time interval Z63 (30, 27) and at a time t7 im Time interval Z70 (32, 28) the limit of twenty-eight radiation units.
  • the radiation exceeds Power of the comparison signal LB the limit of twenty-eight radiation units already at time t63, rises to a maximum of forty radiation units up to a time t9 in the time interval Z90 (40, 28) and remains constant at this maximum from this time t9 until a time t10 .
  • the modulation does not exceed the limit value and the radiation power varies from twenty-three to twenty-eight radiation units from time t63 to time t10.
  • FIG. 2 in which the time course of a binary signal and of modulation signals is shown.
  • a sending subscriber first generates a first and a second modulation signal provided with the modulation clock 3 (FIG. 1) in the form of a first and a second modulation stream 5, 6, from which the subscriber, by adding these streams, generates a modulation stream 7 for amplitude modulation Binary data information of the binary signal la forms.
  • This modulation current 7 has four pulse heights 8, 9, 10, 11 and, as will be shown below, causes a current to flow through a transmitter diode.
  • the modulated transmission signal 4 (FIG.
  • the receiving subscriber assigns bit information "1" to a group of radiation powers equal to or greater than 50%, bit information "0" to a group of transmission powers less than 50%.
  • FIG. 3 in which a block diagram of a transmission device is shown.
  • the in Figures 1, 2 and 3 the same parts are provided with the same reference numerals.
  • the transmitting device comprises in particular a transmitter in the form of a transmitting diode 12 which is connected to a positive supply potential 13 and is connected to a ground potential 16 via a first and a second driver stage 14, 15. Further components of this transmission device are a first and a second AND gate 17, 18 and also a power output controller 19.
  • the characteristic curve of the transmitter 12 can be stored in the controller 19, from which the relationship between a modulation current 7 flowing through the transmitter 12 and the radiation power of the transmitter 12 caused by this current 7 results.
  • the controller 19 From this characteristic and a binary signal 1c that can be fed to the controller 19, the controller 19 first determines the average radiation power over a time interval in the event of an unmodulated light transmission. If this average radiation power is above the limit value, the controller 19 generates a first and a second binary enable signal 23a, 23b, which has the modulation clock 3 (FIG. 1), the first enable signal 23a leads the first AND gate 17, the second enable signal 23b the second AND Link 18 and both AND links 17, 18 to binary signal la, which is time-shifted by a time interval ⁇ t from binary signal lc.
  • the driver stages 14, 15 are activated together or alternately in such a way that a modulation current 7 with four pulse heights 8, 9, 10, 11 (FIG. 2) is brought about, whereby the transmitter 12 emits a transmission signal 4 with four radiation power levels of 0%, 50%, 100% or 150%.
  • the controller 19 takes into account the level changes of the binary signal la, z. B. at times tO, tl, whereby a modulation current 7 flowing at times tO, t03 through the transmitter 12 is to be generated, which causes a light transmission with a radiation power level of 150%.
  • the AND logic element 18 activates the driver stage 15 at the times t0, t03 for the duration of a modulation cycle 3, as a result of which the second modulation current 6 flows through a current path 21.
  • the AND gate 17 activates the driver stage 14 from the time t0 to the time t1, as a result of which the first modulation current 5 flows through a current path 22. Due to the dimensioning of the current path 22 with a resistor 20 and the current path 21 with two such resistors 20, the first modulation current 5 flows through the current path 22 with a proportion of 2/3 and through the current path 21 the second modulation current 6 with a proportion of 1 / 3, based on the total current, ie based on the modulation current 7.
  • the level of the first modulation current 5 corresponds to the level of a current flowing through the transmitter 12 during an unmodulated light transmission
  • the level of the second modulation current 6 corresponds to half the level this corresponds to the current flowing through the transmitter 12 during an unmodulated light transmission.
  • the modulation current 7 flowing through the transmitter 12 therefore comprises a one and a half level of this current flowing through the transmitter during an unmodulated light transmission.
  • the driver stages 14, 15 are enabled jointly or alternately by the enable signals 23a, 23b in such a way that a modulation current 7 with four pulse heights 8, 9, 10, 11 ( Figure 2) is effected.
  • the pulse height 8 corresponds to a level 0, the pulse height 9 to half, the pulse height 10 to a simple one and the pulse height 11 is one and a half times the level, based on a current flowing through the transmitter during an unmodulated light transmission.
  • a transmission signal 4 is thereby generated, whereby the transmitter 12 emits light with four radiation power levels of 0%, 50%, 100% and 150%, based on the maximum value of the radiation power in the case of unmodulated light transmission.

Landscapes

  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Optical Communication System (AREA)

Abstract

L'invention concerne un procédé permettant de régler un émetteur d'un abonné d'un système de transmission optique de données à une puissance d'émission. Cet abonné peut produire un signal d'émission à partir d'un signal binaire et le transmettre à un autre abonné du système de transmission optique de données. Ce signal d'émission peut comporter des impulsions lumineuses pouvant être transmises avec une puissance d'émission correspondant à une donnée binaire '0' ou '1'. Des mesures appropriées permettent de régler la puissance d'émission de telle façon que, par exemple, dans l'espace d'un intervalle de temps donné, la puissance d'émission déterminée ne dépasse pas une valeur limite donnée, ce qui augment la durée de vie de l'émetteur.
EP99960905A 1998-11-16 1999-11-16 Procede de regler un emetteur a une puissance d'emission Withdrawn EP1131927A1 (fr)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE19852749 1998-11-16
DE1998152749 DE19852749A1 (de) 1998-11-16 1998-11-16 Verfahren zur Erzeugung eines Sendesignals aus einem Binärsignal
DE19855225 1998-11-30
DE1998155225 DE19855225A1 (de) 1998-11-30 1998-11-30 Verfahren zum Einstellen einer Strahlungsleistung in einem Sender
PCT/DE1999/003648 WO2000030309A1 (fr) 1998-11-16 1999-11-16 Procede de regler un emetteur a une puissance d'emission

Publications (1)

Publication Number Publication Date
EP1131927A1 true EP1131927A1 (fr) 2001-09-12

Family

ID=26050181

Family Applications (1)

Application Number Title Priority Date Filing Date
EP99960905A Withdrawn EP1131927A1 (fr) 1998-11-16 1999-11-16 Procede de regler un emetteur a une puissance d'emission

Country Status (3)

Country Link
US (1) US20020018270A1 (fr)
EP (1) EP1131927A1 (fr)
WO (1) WO2000030309A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100561885C (zh) * 2005-09-29 2009-11-18 中兴通讯股份有限公司 集群群组前向补充信道功率过载控制装置及方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1091439B (it) * 1977-10-13 1985-07-06 Studi E Lab Telcomunicazioni S Procedimento e sistema di modulazione e demodulazione per trasmissione numerica
FR2652215B1 (fr) * 1989-09-19 1994-06-10 France Etat Procede de codage d'un signal numerique, codeur et decodeur pour la mise en óoeuvre de ce procede, procede de regeneration et regenerateur correspondant.
DE4423264A1 (de) * 1994-07-02 1996-01-11 Leuze Electronic Gmbh & Co Optoelektronische Vorrichtung zum Übertragen von Datenworten

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0030309A1 *

Also Published As

Publication number Publication date
WO2000030309A1 (fr) 2000-05-25
US20020018270A1 (en) 2002-02-14

Similar Documents

Publication Publication Date Title
EP2245812B1 (fr) Procédé de transmission de données numériques sans scintillement dans un système de transmission optique a espace libre
DE3007958C2 (de) Opto-elektonisches Übertragungssystem
DE69829246T2 (de) Mobilkommunikationssystem unter Verwendung von Frequenzspringen
EP0656700A1 (fr) Système optique pour la transmission d'un signal à plusieurs étages
DE3705697A1 (de) Schaltungsanordnung zur stabilisierung des laser-vorstroms fuer ein im burst-betrieb arbeitendes lichtleiter-kommunikationssystem
DE2844293A1 (de) Verfahren und system der modulation und demodulation zur digitalsignaluebertragung
EP0999955B1 (fr) Systeme pour transmettre des donnees dans un vehicule a moteur
DE19900869A1 (de) Steuer- und Datenübertragungsanlage
DE3608930A1 (de) Verfahren zur regelung der optischen leistung eines lasers und schaltung zur ausuebung des verfahrens
DE3147555C2 (fr)
DE3100929A1 (de) "anlage zur informationsuebertragung mit einer optischen sammelleitung"
WO2019243290A1 (fr) Système de caméra temps de vol à puissance de sortie optique ajustable
EP2284040A1 (fr) Procédé de commande de la puissance d'éclairage d'un faisceau lumineux émis par une installation d'éclairage de véhicule
DE2539438C3 (de) Strahlenschranke
WO2000030309A1 (fr) Procede de regler un emetteur a une puissance d'emission
DE19855225A1 (de) Verfahren zum Einstellen einer Strahlungsleistung in einem Sender
EP1014605B1 (fr) Système de codage optique pour une série d'impulsions
DE19852749A1 (de) Verfahren zur Erzeugung eines Sendesignals aus einem Binärsignal
DE3048978A1 (de) Optisches datenuebertragungssystem
EP0771088A2 (fr) Système de transmission par fibre optique avec mode de test
EP3895383A1 (fr) Système de communication de réseau présentant une modulation de courant bidirectionnelle aux fins de la transmission de données
DE3304300A1 (de) Verfahren und einrichtung zur busanforderung und sammelquittierung in einem prozessbus-system
DE4332475C2 (de) Fahrzeuggerät zur Datenübertragung an eine ortsfeste Bake
DE4421441A1 (de) Optisches Nachrichtenübertragungsverfahren und Zwischenverstärker hierfür
EP0085849A2 (fr) Méthode pour réduire la dynamique de niveau dans un système de transmission optique

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

17P Request for examination filed

Effective date: 20010508

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

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: 20030603