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161.发明专利
公开(公告)号：JPH10232316A
公开(公告)日：1998-09-02
申请号：JP4295998
申请日：1998-02-10
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BOTTAZZI LORENZO , DONATI SILVANO , SOREL MARC , TAMBOSSO TIZIANA
Abstract: PROBLEM TO BE SOLVED: To eliminate all of the optical constituting elements existing outside a light source and associated aligning stages and to enable the use of a continuous wave laser diode by collecting the radiation generated from the interaction between the radiation generated at the light source and the optical fiber constituting elements and detecting this radiation. SOLUTION: The semiconductor laser light source 11 delivers the radiation of the wavelength λ through an end face 13 subjected to an antireflection treatment into a fiber length 19. The photodiode 12 is placed behind the light source 11 on a supporting table 10 and is so arranged as to detect the laser radiation from a rear part mirror 3. The fiber 19 is wound 5 to 10 times on a phase modulator 14 and generates periodic signals in the output of the photodiode 12. The effect by the reflection in the optical fiber constituting elements is made identifiable by these periodic signals and these signals are made into a DC signal. The novel measurement technique based on the coherent interaction with the reflected radiation in the same cavity resonator and the oscillation electromagnetic field existing in the cavity resonator is obtd.
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162.发明专利
公开(公告)号：JPH10154959A
公开(公告)日：1998-06-09
申请号：JP31775297
申请日：1997-11-05
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： GAMBINI PIERO , PULEO MARIO
IPC: H04B10/04 , H04B10/00 , H04B10/06 , H04B10/08 , H04B10/142 , H04B10/152 , H04B10/22 , H04L7/00
Abstract: PROBLEM TO BE SOLVED: To provide the method and device to control accurately a phase of a clock signal transferred along with an optical fiber between two points. SOLUTION: A signal to be controlled is sent along with an optical fiber 3 by a wavelength tunable laser 2 whose radiation wavelength is varied as a function of possible phase fluctuation in a reception signal with respect to a reference phase. At a receiving end of the optical fiber 3, part of power of the reception signal is extracted and sent back toward a transmission end, then a control signal is generated. At a transmitter end, a phase of part of the power is compared with a phase of an original signal and the tunable laser 2 is driven so that clock information with a wavelength is sent to be reached to the receiving end having the reference phase.
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公开(公告)号：JPH09127563A
公开(公告)日：1997-05-16
申请号：JP24682496
申请日：1996-08-30
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： MATSUSHIMO ARUTEIGURIA , ERUNESUTO CHIYARAMETSURA
Abstract: PROBLEM TO BE SOLVED: To improve spectrum conversion efficiency. SOLUTION: On the basis of a solving method known as spectrum inversion (or light phase conjugation), a spectrum is changed. This device 1 generally includes a medium like a dispersion shift optical fiber 4. A signal to be varied is sent in the optical fiber together with a pump signal of level which causes modulation unstableness in the fiber 4. A spectrum-inverted light signal is obtained as the output of the fiber 4 and varied in wavelength and its conversion efficiency is high. The spectrum of the pump signal is preferably expanded by, for example, a modulator 5 so as to evade induced Brillouin scatter.
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公开(公告)号：JPH08289447A
公开(公告)日：1996-11-01
申请号：JP8448096
申请日：1996-03-14
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： JIYUZETSUPE KOCHITO
Abstract: PROBLEM TO BE SOLVED: To provide a duct in which ribs are formed on the inner surface of a pipe in order to facilitate insertion of a cable regardless of the ration of diameter between the cable and the pipe (tubular element). SOLUTION: The duct for containing cables of underground communication network comprises one or more tubular elements 1 made of a first plastic substance and is provided, on the inner surface thereof, with spiral ribs 2a, 2b. Alternatively, the rib may be inserted into the tubular element 1.
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公开(公告)号：JPH08279747A
公开(公告)日：1996-10-22
申请号：JP8448196
申请日：1996-03-14
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： MARUKO BURUTSUIO
Abstract: PROBLEM TO BE SOLVED: To speedily match a clock signal with the clock of a data signal by allowing a main PLL of the clock extracting circuit to control VCO by continuously controlling the phase and allowing an auxiliary PLL to lock a main loop by oscillating the VCO at a frequency close to an operating frequency. SOLUTION: The extracting circuit for the clock from the high-speed data stream has twin-loop PLL structure. The main loop consisting of a phase detector DFS, a driving current generator PC1, a loop filter FI, and VCO locks the phase of a clock signal which is generated by the VCO and present on a wiring to data arriving at the wiring 1. The subordinate loop consisting of a threshold comparator CS, a driving current generator PC2, a filter FI, and VCO locks the main loop by oscillating the VCO at the frequency close to a desired frequency. When the VCO oscillates a frequency greatly different from the optimum frequency and the wiring frequency is too low, the frequency detector DFR outputs an error pulse to the wire 4 and when the frequency of the wiring 2 is too high, an error pulse is generated to a wiring 5 to control the oscillation frequency of the VCO, thereby approximating its frequency to the desired frequency.
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Patent Agency Ranking
公开(公告)号：JPH08256184A
公开(公告)日：1996-10-01
申请号：JP5362996
申请日：1996-02-19
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BUARUTAA BENEDEITSUTO
IPC: H04L27/00 , H03M13/23 , H03M13/25 , H03M13/29 , H03M13/41 , H03M13/45 , H04L1/00 , H04L25/03 , H04L27/38 , H03M13/12
Abstract: PROBLEM TO BE SOLVED: To provide a method for receiving a signal affected by inter-sumbol interference, especially a signal which is encoded and modulated by a TCM system. SOLUTION: A receiver containing two viterbi decoders 1 and 2 which are cascade-connected is used for receiving a TCM modulation signal. The first decoder 1 operates in accordance with software output viterbi algorithm SOVA and the output contains rigid decision on a reliable degree paraffieter and a transmission symbol. The output of the first decoder 1 which substantially considers the storage effect of a channel is generally sent to the second viterbi decoder 2 executing actual decision after the operation of an inverse interleaving operation by comparing the influence of inter-symbol interference. The method and the device are suitable for a digital communication system such as a micro wave radio link.
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167.发明专利
公开(公告)号：JPH08237195A
公开(公告)日：1996-09-13
申请号：JP34601895
申请日：1995-12-11
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： ROBERUTO KADETSUDOU , RITSUKARUDO KARUBUAANI , JIYUZETSUPE FUERARISU , ROBERUTO RANO , EMIRIO BUETSUTSUOONI
IPC: H04B10/02 , H04B10/20 , H04B10/213 , H04J14/02 , H04L12/437
Abstract: PROBLEM TO BE SOLVED: To efficiently use a transmission capacity. SOLUTION: In a ring network communication structure for communication with optical transmission lines 3A and 3B, plural nodes 2A...2E are mutually connected by at least first and second optical transmission lines 3A and 3B like optical fibers. A first wavelength λ1 is used for communication in one direction on the first transmission line 3A out of this pair of optical transmission lines to perform transmission in a ring network based on a WDN structure, and a second wavelength λ2 is used on the other optical transmission line 3B to perform communication in the opposite direction. If one of these connections gets faulty, nodes 2B and 2C adjacent to each other which cannot be connected are reconfigured, and the first wavelength λ1 is used on the second transmission line 3B and the second wavelength λ2 is used on the first transmission line 3A to continue the communication through another route given from the ring network. This structure is suitably applied to an SDH optical fiber ring network.
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公开(公告)号：JPH08110789A
公开(公告)日：1996-04-30
申请号：JP17555395
申请日：1995-06-20
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： FOTI ENZO , NEBBIA LUCIANO , SANDRI STEFANO
Abstract: PURPOSE: To reduce the processing time, and to improve the natural sound of the synthesizing signal by leaving a part of the original signal, which includes the basic information of each block, as it is, and changing the residual part. CONSTITUTION: In this sound signal synthesizing method by connection of waveform, which present the unit of element of the sound signal, with the lapse of time, at least the waveform related to the sound to be output as voice is divided into plural blocks, which are synchronized with the basic frequency of the signal and which correspond to the response of sound pipe in relation to a continuous stimulus impact of a vocal cord, and weighting is performed in each block, and the signal generated by the weighting is substituted with a copy thereof when the time is shifted by the quantity, which depends on the rhythm element information, and the sifted signal are overlapped and added to each other for sound synthesis. In each block of the original signal to be regenerated by the synthesis, a non-changed part of the original signal, which includes the basic information and which is not changed in the synthesized signal so as to be regenerated, is discriminated, and weighting, overlap and addition are performed to the residual block.
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公开(公告)号：JPH07335957A
公开(公告)日：1995-12-22
申请号：JP16158495
申请日：1995-06-06
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BUARUTERU BERA , PAORO PEREGURIINO
Abstract: PURPOSE: To provide a circuit which enables a high speed drive of a laser diode and efficiently operates at a speed meeting requirements given by an optical fiber communication system to avoid interference between an optical source drive current and bias current. CONSTITUTION: When a data transmitting source feeds a drive current to the input I of a cascade of CMOS inverters, this cascade can be driven by the cascade of inverters having characteristics about the size of p- and n-type CMOS transistors at a speed enough for the input capacity of transistors SM. When the voltage is at a low logic level on the input I, the gate of MS goes to a high logic level to cut off the p-type transistor and only a bias current fed from MP flows to a terminal L. The current flowing to this terminal L is given by addition of the bias current to a modulating current fed from MM, and both currents depend on a voltage fed to terminals M and P but are mutually independently adjustable.
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公开(公告)号：JPH07307720A
公开(公告)日：1995-11-21
申请号：JP14253193
申请日：1993-05-24
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： ARESANDORO KABUACHIUTEI , MARIO PUREO
Abstract: PURPOSE: To provide an optical multiple separating device in which the properties of transmission data can be prevented from being deteriorated, and a critical high speed bit processing is not necessary by extracting the optical signal of a prescribed channel from the multiplexed signal of a carrier light modulated by time-division multiplexed(TDM) data, and transmitting it to a corresponding light receiver. CONSTITUTION: This is a device for extracting the optical signal of a prescribed channel from the multiplexed signal of a carrier light modulated by TDM (time- division multiplexed) data. A semiconductor light amplifier SA which adjusts a gain by a saturation effect by the algebraic sum of the power of an input signal is used. This amplifier SA simultaneously receives the modulated carrier light and a sampling carrier light with wavelength different from that of the modulated carrier light. An optical filter F1 connected at the output side of the amplifier SA extracts the sampling carrier light modulated by a data signal from the output of the amplifier, and supplies the signal of the channel to an output side.
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