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公开(公告)号：JPH11326657A
公开(公告)日：1999-11-26
申请号：JP10154799
申请日：1999-04-08
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BOSCHIS LAURA , GNAZZO ANGELANTONIO , ROSSOTTO ORIANA , TALLONE LUIGI
Abstract: PROBLEM TO BE SOLVED: To obtain a grating which has a narrow reflection factor spectrum distant from a 2nd lobe and reduced equivalent length. SOLUTION: A grating 10 formed in the core of an optical fiber 1 has a modulation profile, which is uneven and asymmetrical in refractive index along the length and the profile is represented with a curve which gradually and monotonously increases from a minimum value which is substantially zero to a maximum value. Here, the minimum value has a substantially horizontal tangent and corresponds to the end of the grating 10 and the maximum value also has a substantially horizontal tangent and corresponds to the other end of the grating 10.
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公开(公告)号：JPH11317966A
公开(公告)日：1999-11-16
申请号：JP37504198
申请日：1998-12-14
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： QUACCHIA MARCO
IPC: H04N17/00
Abstract: PROBLEM TO BE SOLVED: To provide a method for allowing distortions to be easily perceptible by obtaining a displacement index against a corresponding block group in a previous frame against a detected block, comparing it with a first threshold and giving distortions only to a block whose displacement index is not less than the threshold. SOLUTION: The sequence of a test picture is digitally converted in an analog/digital converter 2 and is given to a testing device 3 such as a digital encoder/ decoder and a reference picture generation system 4, for example. The system 4 is adapted so that a specified distortion is added to the picture. Generally, the added distortion is selected from distortions introduced by a processing. Outputs of the testing device 3 and of the system 4 are given to a digital/analog converter 5, which gives reformed sequence to a monitor 6 for comparison by an observer. The converters 2 and 5 can mutually and directly be connected.
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13.发明专利
公开(公告)号：JPH11225369A
公开(公告)日：1999-08-17
申请号：JP32439998
申请日：1998-10-30
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： PIOLINI FLAVIO
Abstract: PROBLEM TO BE SOLVED: To provide a channel assignment method that takes a position of a terminal, a geographic characteristic of cells and also a moving characteristic of the terminal into account. SOLUTION: In the mobile communication system conducting space division multiplex access, a channel to be assigned to a terminal is decided by evaluating an assignment cost to each channel under the condition of re-use of channels. The cost is a function of a mean time that elapses between two consecutive channel assignment jobs to a terminal and then a channel maximizing the time is identified. The evaluation is conducted by using a cost coefficient that takes information relating to cell topology and information of terminal mobility into account. The cost coefficient is decided by re-dividing a cell into sectors in the initializing stage of the system and detecting the moment when cell collision between terminals takes place.
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公开(公告)号：JPH11225070A
公开(公告)日：1999-08-17
申请号：JP32440098
申请日：1998-10-30
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BURZIO MARCO
Abstract: PROBLEM TO BE SOLVED: To obtain a high performance phase locked loop circuit. SOLUTION: This phase locked loop circuit includes an oscillator 5, which is usually configured as a voltage controlled oscillator VCO and is operated selectively according to different input/output characteristics. The phase locked loop circuit further includes a means 81 that selectively control the operation of the oscillator 5 under any of the input/output characteristics determined selectively according to the operating state of the phase locked loop 1.
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公开(公告)号：JPH11139832A
公开(公告)日：1999-05-25
申请号：JP22520398
申请日：1998-07-27
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BRAGLIA MARCO , DAI GUOJUN , MOSSO SABRINA
Abstract: PROBLEM TO BE SOLVED: To provide an improved induction electric furnace from which the temp. nonuniformity between different regions is removed. SOLUTION: The supporting device 6' for a crucible 3 of the glass synthesizing induction electric furnace and more particularly the induction electric furnace for fluorozirconate used in an fiber for communication is connected to a pair of sleeves 7, 9 and an annular element 8 constituting an actual supporting member is inserted therebetween. The first sleeve 7 has a such a size in a longitudinal direction that the crucible 3 is supported within this annular element 8 apart a specified spacing from a plane element 5'. The second sleeve has such a size in a longitudinal direction that the top end of the second sleeve exists at a level higher than the top end of the crucible so as to allow the existence of the temp. region uniform over at least the entire height of the crucible.
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Patent Agency Ranking
公开(公告)号：JPH10319255A
公开(公告)日：1998-12-04
申请号：JP15077798
申请日：1998-05-15
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BOSCHIS LAURA , ROSSOTTO ORIANA , TALLONE LUIGI
IPC: G02B6/13 , B29D11/00 , G02B20060101 , G02B5/18 , G02B5/26 , G02B6/02 , G02B6/10 , G02B6/124 , G02B6/136 , G02B6/255 , G02B6/293 , G02B6/34
Abstract: PROBLEM TO BE SOLVED: To provide a method and a device for uniformly irradiating all fibers or waveguides for writing a grating. SOLUTION: This method and a device simultaneously form the same Bragg grating in a different optical fiber or waveguide, the fiber/waveguide 1 is mounted in line on a common supporting base 2 together with a phase mask 3 and the phase mask 3 gives the desired intensity distribution to a radiating beam for writing a grating. The common supporting base 2 is moved back and forth in the lateral direction to the longitudinal axis of the fiber or the waveguide at appropriately low frequency so as to expose the fiber/waveguide to the radiating beam for a time enough to start changing the refractive index when each fiber/waveguide passes through the radiating beam.
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公开(公告)号：JPH1065623A
公开(公告)日：1998-03-06
申请号：JP18328097
申请日：1997-06-25
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： RICCARDO CALVANI , RENATO CAPONI
IPC: H04B10/00 , G02F1/365 , H04B10/04 , H04B10/06 , H04B10/142 , H04B10/152 , H04B10/18
Abstract: PROBLEM TO BE SOLVED: To obtain a pulse so that the product of band width with a duration time exists within a requiured limit by utilizing peak power as a control parameter. SOLUTION: A pulse source includes a color center laser 1 and the pulse discharged by the laser 1 is transmitted to the inside of a distribution shift optical fiber 4 with certain length. A coupler 11 transmits a part of pulse power to a power meter 12 or to the same kind of device for measuring the peak power of the pulse. The power meter 12 is connected to a computer 13. The computer 13 controls a required peak power variation and receives information about the duration time of the pulse which is outputted from the device. The information is given by a self correlator 8 and the self correlator 8 receives a part of output power with another coupler 10. Conventional fibers 5a and 5b are arranged along a pulse path. The whole length of the fibers is the one for compensating a phase effect as the function of a frequency.
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公开(公告)号：JPH08211258A
公开(公告)日：1996-08-20
申请号：JP27640995
申请日：1995-09-29
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： BURUUNO BOSUCHIKA , FURANKO DERUPIANO , RUKA PESANDO
IPC: G02B6/42 , H01S5/00 , H04B10/12 , H04B10/135 , H04B10/14 , H04B10/2581 , H01S3/18 , H04B10/13
Abstract: PROBLEM TO BE SOLVED: To provide a transmitter module having a structure in which problems by length of connecting line, parasitic effect, and effect of signal reflection by impedance mismatching are minimized, and thermal dissipation is satisfactory promoted with a small operating power. SOLUTION: In a transmitter module for optical mutual connection comprising a metal vessel A for housing a light emitting device, an integrated circuit B including the driving circuit of the light emitting device, and an optical fiber extended to the outside of the metal vessel A, the light emitting device is installed on a metal ground area D formed on the integrated circuit B. A cathode is electrically connected to the ground area D. An anode is connected to a second metal area N connected to the driving circuit output.
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公开(公告)号：JPH07277756A
公开(公告)日：1995-10-24
申请号：JP8086295
申请日：1995-03-14
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： MARUKO BURAGURIA , JIYUSETSUPE KOCHIITO
IPC: G02B6/00 , C03B37/012 , C03B37/014 , C03C13/04
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公开(公告)号：JPH07270730A
公开(公告)日：1995-10-20
申请号：JP8771995
申请日：1995-03-22
Applicant: CSELT CENTRO STUDI LAB TELECOM
Inventor： HAINTSUUKURISUTOFU NAITSUERUTO , DOMENIKO KAMUPI
Abstract: PURPOSE: To suitably execute a complicated logic by including a guide zone which consists of a series of layers that are alternately changed between a quantum well and a barrier layer and sending parallelly luminous radiation to be processed to the layers in quantum well modulators where an electro- optical modulator makes a pair. CONSTITUTION: A pair of quantum well modulators M are applied reverse bias by a variable voltage source U through a load impedance Z, a light beam Fi is entered into a guide zone by an optical system L1 and a light beam Fo which is collimated by an optical system L2 is taken out. The impedance Z sets an operating point of the modulators M which are equal to a PIN diode and brings about a positive feedback. An luminous radiation absorption coefficient is reduced by an operational wavelength. As backward direction applied voltage increases, photocurrent which crosses the modulators M decreases, voltage drop in the impedance Z is decreased and the increase of backward applied voltage is brought about. A desired transfer function Po/Pi can be selected by changing voltage of a variable generator U.
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