FR2536927A1 - MANUAL CHANNEL TESTING DEVICE OF A FIBERGLASS SUBSCRIBER OPTICAL LINE WITH WAVELENGTH BIDIRECTIONAL MULTIPLEX - Google Patents

Abstract

MANUAL TEST DEVICE OF A SUBSCRIBER OPTICAL CHANNEL WITH MULTIPLEX PER WAVELENGTH. THROUGH A BUTTON 1 AND A TRIP CIRCUIT 2, THE LASER TRANSMITTER 6 IS CONNECTED FOR A PERIOD WITHOUT OPERATION AND OPTICALLY EMITS PERMANENT SYNC INFORMATION, DELIVERED BY THE HF7 TRANSMITTER, AND WHICH, AT L THE OTHER END OF THE SUBSCRIBER CHANNEL, IS DETECTED AFTER OPTO-ELECTRIC CONVERSION IN CONVERTER 3 OF THE HF5 RECEIVER, INDICATED IN THE FORM OF A "DSE" LOGICAL SIGNAL, THEN TRANSMITTED TO A CIRCUIT 2 TO TRIGGER THE TRANSMISSION TO THE REAR OF THE PERMANENT SYNC INFORMATION.

Description

-2536927

  The present invention relates to a device for manually testing the channels of a fiber optic subscriber optical line with multiplex

  bidirectional by wavelength, in which the subscriber line.

  includes the series coupling of an RF transmitter, an electro-optical converter (laser transmitter), an opto-electric converter

and an HF receiver.

  The use of fiberglass transmission channels with multiple

  tiplex per wavelength in the connection area of the subscriber imposes more and more complex measurement and test techniques

  to determine the precise function of the various transmission channels

  if we. The subject of the invention is a device which makes it possible, with simple means, to obtain an overview of the functionality of the channels allocated to the various wavelengths on a subscriber optical line.

  operated in multiplex by wavelength.

  According to an essential characteristic of the invention,

  Via a key and a trip circuit, the laser transmitter is connected during a period without operation and optically transmits permanent SYNC information, delivered by the RF transmitter and which at the other end of the channel subscriber, is detected after opto-electrical conversion in the HF receiver converter,

  indicated as a "DSE" logic signal by an electronic diode

  luminescent, then transmitted to a trigger circuit of the

  forward transmission of permanent SYNC information.

  The invention provides two important advantages: 1 Testing a channel requires only a few components in addition to existing devices in the optical transmission channel,

  2 the test only intervenes in the connections with the conver-

  electro-optical or opto-electric weavers and HF transmitters or HF receivers Inadvertent connections by

  test tracks are virtually excluded.

  Other features and advantages of the invention will be

  better understood using the detailed description below of a

  embodiment and the accompanying drawings in which Figure 1 shows the mounting of a manual channel test forward and backward; and FIG. 2 represents the tripping circuit of the manual test

of a channel.

  As shown in FIG. 1, a key 1 (1 ') for triggering the test is assigned to each electronic converter.

  optical 6 or 6 '(laser transmitter) As will be specified later;

  However, the test can only be carried out in the absence of data transmission on the channel, ie during non-operating periods. the key (or 1 ') causes the trip circuit 2 (FIG. 2) or 2' to supply a "test" logic signal to the RF transmitter 7 (or 7 '). The "test" signal is connected in normal operation HF transmitter 7 (or 7 V) of the channel located in

  the waiting state with low energy consumption, and makes it

  Simultaneously, a permanent signal SYNCO The transmission of a permanent SYNC signal means that each time slot of the entire time multiplex frame, generated by the RF transmitter 7 (or 7 ') is occupied by a synchronization word. The transmission of data is blocked as long as a permanent SYNC is emitted The electric signal delivered by the RF transmitter to the electro-optical converter 6 (or 6 ') (via the lines D = data and BT bit frequency) is converted in the latter into optical signals wavelength X 3 (or X 4) The optical level appearing at the far end of the transmission path and assigned to the wavelength X 3 (or X 4) is detected by the opto-electric converter 3 (or 3 '), then converted into electrical signals The incident serial information is divided by the converter 3 (or 3'), which notably comprises a PLL circuit (phase control loop), into a serial data stream D and a frequency BT bit of accompaniment, obtained

  by the PLL circuit, then are transmitted to the receiver HF 5 (or 5 ').

  The information flow is detected in the latter and the logical signal "DSE" is delivered during the identification period of the permanent SYNC.

  If the logical signal "DSE" was not used at the reception

  In order to connect the laser transmitter (electro-optical converter 1 or 1 ') to the rear, a loop would

no longer to cut the test.

  To prohibit this phenomenon, the invention uses the circuit.

  Trigger 2 (or 2 ') shown in Figure 2 It is arranged in the immediate vicinity of the key 1 (or 1') and essentially consists of a rocker RS, formed by two NAND operators 11 and 12 The input of set to 1 is controlled by the operator NAND 9

  and the reset input to O by the NAND operator Four

  pulse meters 13, 14, 15 and 16 are further provided, which convert the static signals applied to their input into pulses as a function of the direction of the transition during the application or suppression of the static signals. the

  FIG. 2, the operation of the key (or 1 ') can not

  only when the signal O S is simultaneously 0 also.

  The signal O S comes from the laser transmitter (electronic converter

  optical 6 or 6 ') and is derived from its current -de threshold The latter is used as criterion of the operating state-of the transmitter

  The NAND 8 operator groups together the signals from the

  13 when the key 1 assigned to the electro-optical converter 6 of wavelength X 3 is for example pressed, the latter emits optically the permanent signal SYNC delivered by the transmitter RF 7 ,

  when no data transmission is in progress (see Figure 1).

  At the far end of the wavelength path X; the permanent SYNC signal is detected after opto-electrical conversion in the 3 'receiver of the HF 5' receiver, delivered as a signal

  logic "DSE", then indicated by the light-emitting diode 4 '.

  The signal "DSE" acts simultaneously on the trigger circuit 2 'and therefore produces the optical emission by the laser transmitter 6' of a

  permanent SYNC signal delivered by the RF transmitter 7 'of said

  This backward optical signal X is converted into serial electrical signals by the converter 3; the signal is detected

  the HF-5 receiver and provides the "DSE" logic signal.

  deny is indicated by a light-emitting diode 4 to show

  what channels? 3 and X 4 are in good condition.

2536 ç 27

  The release of the key 1 interrupts the transmission of the logic signal "test" in the trigger circuit 2 The laser transmitter 6 is cut off The signal "DSE" therefore also disappears in the trigger circuit 2 'The test is thus interrupted on both channels. Of course, various modifications may be made by those skilled in the art to the principle and to the devices which have just been described as non-limiting examples,

  without departing from the scope of the invention.

Claims (3)

claims   1 Manually testing device for channels of fiber optic subscriber optical line with bidirectional wavelength multiplex, wherein the subscriber line comprises the series coupling of an RF transmitter, a electro-optical converter (laser transmitter),   an opto-electric converter and an RF receiver, said ten-   positive being characterized in that via a key (1 or 1 and a trip circuit (2 or 2 '), the laser transmitter (6 or 6') is connected during a period without operation and optically transmits permanent SYNC information, delivered by the RF transmitter (7 or 7 ') and which, at the other end of the subscriber channel, is detected after opto-electrical conversion in the converter (3 or 3') of the HF receiver (5 or 5 '), indicated as a "DSE" logic signal by a light-emitting diode (4 or 4'), then transmitted to a tripping circuit (2 or 2 ')   forward transmission of permanent SYNC information.   2 Device according to claim 1, characterized in that a light emitting diode indicates to the operator the start of the test by application of the logic signal "test" to the circuit of trigger (2 or 2 ').   3 Device according to claims 1 and 2, characterized in that   the tripping circuit is constituted by an RS flip-flop, formed   by NAND operators (11 and 12), NAND operators of   Mande (9 and 10) and pulse shapers (13, 14, 15 and 16) converting the static signals of the key (1 or 1 ') and "DSE" into pulses; and the output of the pulse shaper (13) is connected to an input of a NAND operator (8), the second of which   input is controlled by the logic signal "O S".