公开(公告)号：JPH11331043A

公开(公告)日：1999-11-30

申请号：JP13934798

申请日：1998-05-21

申请人： NIPPON ELECTRIC ENG

发明人： ISHIHARA TADASHI ,  HARADA CHIHIRO

IPC分类号： H04B1/74 ,  H04B10/03 ,  H04B10/032 ,  H04B10/035 ,  H04B10/079 ,  H04B10/80 ,  H04B10/02

摘要： PROBLEM TO BE SOLVED: To provide a redundant system optical transmission line switching device with a simple configuration capable of preventing the occurrence of leak and unnecessitating an optical receiver exclusively for a monitor signal. SOLUTION: A redundant system optical transmission line switching device 100 detects an error in an optical fiber cable 4a of an active system optical transmission line 22a and an optical fiber cable 4b of a standby system optical transmission line 22b, uses a power supply connection means that connects a light receiving element of an optical receiver in the normal optical transmission line system to a power supply to select an optical signal from the active optical transmission line 22a and the standby system optical transmission line 22b and provides an output of an electric signal.

公开(公告)号：JPH10145307A

公开(公告)日：1998-05-29

申请号：JP30266796

申请日：1996-11-14

申请人： NIPPON ELECTRIC ENG

发明人： ISHIHARA TADASHI

IPC分类号： H03F1/32 ,  H04B15/00

摘要： PROBLEM TO BE SOLVED: To generate intermodulation distortion required for the intermodulation distortion compensation circuit with a superior characteristic through the configuration of easy adjustment. SOLUTION: An input frequency multiplex signal is distributed into two at a distributer 3a, so as to be opposite in phase to each other, each distribution signal is led out via composite diodes 4a whose characteristics are the same, and the distribution signals are synthesized by a synthesizer 3b using a balun transformer to produce odd number degree intermodulation distortion component in the synthesis output. Otherwise, the frequency multiplex signal is distributed into two, so as to be opposite in phase to each other. Each distribution signal is led out via composite diodes 4a whose characteristic are the same, and the distribution signals are synthesized by a resistance synthesizer 7a, so as to produce even number degree intermodulation distortion component in the synthesis output. Since odd number and even number degree produce odd number degree intermodulation distortion components are obtained with high accuracy, the distortion components are mixed in an input frequency multiplex signal to eliminate the distortion components included in the input signal.

公开(公告)号：JPH0697798A

公开(公告)日：1994-04-08

申请号：JP26738091

申请日：1991-10-16

申请人： NIPPON ELECTRIC ENG

发明人： SUZUKI FUMIO ,  ISHIHARA TADASHI

IPC分类号： H03K17/60 ,  H03F3/50 ,  H03K19/018

摘要： PURPOSE:To provide the output circuit with the high driving ability by stabilizing an output signal voltage level and requiring low consumption current. CONSTITUTION:The signal center potential of an output terminal becomes the double of the base-emitter voltage of a transistor by making the center potentials of signal to be inputted to input terminals 1 and 2 equal. Only when the output signal changes from high voltage to low, the current value of a current source 13 having a current control terminal to be connected to an output terminal 3 is designed to increase. Thus, the output circuit requires low consumption current and provides the high driving abilitly.

公开(公告)号：JP2001230638A

公开(公告)日：2001-08-24

申请号：JP2000040583

申请日：2000-02-18

申请人： NIPPON ELECTRIC ENG

发明人： YOSHIDA YUKO ,  ISHIHARA TADASHI

IPC分类号： H03F1/56 ,  G06F17/50 ,  H03F3/08

摘要： PROBLEM TO BE SOLVED: To provide a method for design of a precise optical receiving circuit and an optical transmitting circuit. SOLUTION: The single unit S parameter characteristics of an optical component are extracted and converted into data applicable to simulation, and an impedance matching circuit 7 is designed on the same simulation as an electrical component. The impedance matching circuit 7 between the optical component and the electrical component is designed by combining a pattern form, a resistor 15, a coil 16 and a capacitor 17.

公开(公告)号：JPH09283830A

公开(公告)日：1997-10-31

申请号：JP8543096

申请日：1996-04-08

申请人： NIPPON ELECTRIC ENG

发明人： HARADA CHIHIRO ,  ISHIHARA TADASHI

IPC分类号： H01S5/042 ,  H01S5/00 ,  H01S5/06 ,  H01S5/068 ,  H01S5/0683 ,  H01S3/133 ,  H01S3/096 ,  H01S3/103

摘要： PROBLEM TO BE SOLVED: To provide an optical modulation controller which stabilizes the operation of an optical modulator, by canceling the variation of the optical modulation in this modulator, if any. SOLUTION: An optical modulation controller 1 comprises a thermistor 5 and a Peltier cooler 6, both disposed in an optical modulator the modulation of which varies with the change of the ambient temp. of a light emitting element 3, means 7, 8, 9 for detecting the variation of the optical modulation degree, signal generating means 10 for generating a control signal having a value depending on the variation and varying direction of the detected optical modulation degree, and temp. adjusting means 11 for controlling the quantity of heat absorption or generation of the cooler 6, based on the generated control signal, thereby changing the ambient temp. of the light emitting element 3 at variation of the optical modulation.

公开(公告)号：JP2001215362A

公开(公告)日：2001-08-10

申请号：JP2000021589

申请日：2000-01-31

申请人： NIPPON ELECTRIC ENG

发明人： ISHIHARA TADASHI

IPC分类号： G02B6/40

摘要： PROBLEM TO BE SOLVED: To provide a highly reliable optical fiber connector that prevents damage to the end face of an optical fiber and that eliminates wrong connection in connecting plural optical fibers. SOLUTION: The optical fiber connector is equipped with magnetic bodies 2a, 2b having holes 14a, 14b for inserting optical fibers 1a, 1b; the magnetic bodies 2a, 2b are provided with the N pole and the S pole on the faces 15a, 15b connecting with the opposite optical fiber connectors 16a, 16b; and the optical fibers 1a, 1b are fixed on the magnetic bodies 2a, 2b so that the optical axis becomes perpendicular to the line connecting the two poles. The end face of the optical fibers 1a, 1b is suitably arranged on the center of the connecting faces 15a, 15b of the optical fiber connectors 16a, 16b. It is also possible that, with plural holes drilled on the magnetic bodies, a plurality of optical fibers are inserted and fixed.

公开(公告)号：JPH0983259A

公开(公告)日：1997-03-28

申请号：JP23223295

申请日：1995-09-11

申请人： NIPPON ELECTRIC ENG

发明人： ISHIHARA TADASHI ,  HARADA CHIHIRO

IPC分类号： H02M1/12 ,  H03F1/32 ,  H04B10/2507 ,  H04B10/40 ,  H04B10/50 ,  H04B10/60 ,  H04B10/67 ,  H04B10/69

摘要： PROBLEM TO BE SOLVED: To surely compensate intermodulation distortion in the case of transmission of a signal including two carriers or over with different frequencies by generating a signal having distortion nearly equal to waveform distortion of and antiphase to an amplifier circuit and synthesizing the signal with an output of the amplifier circuit. SOLUTION: When a signal from a photodetector 2 includes two carriers or over with different frequencies, an amplifier circuit 8 generates intermodulation distortion due to its nonlinearity. A distortion generating circuit 10 generates distortion having an opposite phase to intermodulation distortion included in an output signal of the amplifier circuit 8. The output signal of the amplifier circuit 8 is given to a synthesizer 7b via a phase adjustment device 9a and in this case the phase adjustment device 9a absorbs a phase shift due to a delay in the distortion generating circuit 10. The signal outputted from the phase adjustment device 9a and the intermodulation distortion outputted from the distortion generating circuit 10 are cancelled in the synthesizer 7b, which provides an output of the signal with low intermodulation distortion.

公开(公告)号：JPH07273598A

公开(公告)日：1995-10-20

申请号：JP5952294

申请日：1994-03-29

申请人： NIPPON ELECTRIC ENG ,  NEC CORP

发明人： AKEYA MIKIJI ,  SASAKI CHIHARU ,  ISHIHARA TADASHI

IPC分类号： H03G3/20 ,  H03G3/02 ,  H03H11/24

摘要： PURPOSE:To adjust the interfacing automatically with respect to a device or a line connecting to an input terminal and an output terminal by controlling three transistors (TRs) in pi connection in the variable attenuation circuit based on stored variable voltage information. CONSTITUTION:When input output impedance information to be set respectively to an input terminal 1 and an output terminal 2 and input information of attenuation information with respect to the input of an output are received from an input section 6, a control section 9 reads corresponding voltage variable information from a storage section 8 to provide an output of the information to a variable voltage section 7. Then the voltage section 7 controls independently three MOS TRs 3 to 5 in pi connection in the attenuation circuit so as to adjust the interfacing of a device or a line connecting to the input terminal 1 and the output terminal 2 based on the input information such as input impedance information, output impedance information and attenuation information or the like automatically.

公开(公告)号：JP2000286800A

公开(公告)日：2000-10-13

申请号：JP8963899

申请日：1999-03-30

申请人： NIPPON ELECTRIC ENG

发明人： HARADA CHIHIRO ,  ISHIHARA TADASHI

IPC分类号： H04J14/00 ,  H04B10/07 ,  H04B10/2507 ,  H04B10/29 ,  H04B10/293 ,  H04B10/564 ,  H04B10/572 ,  H04J1/00 ,  H04J14/02 ,  H04B10/14 ,  H04B10/04 ,  H04B10/06

摘要： PROBLEM TO BE SOLVED: To suppress a carrier level deviation at the time of multistage connection by correcting the levels of all the plurality of carriers installed and inputted between arbitrary local stations. SOLUTION: In a sub-carrier multiplex system optical network, a center station 16, local stations 17a-17f and a level correction device 18 are connected in a circle through optical fiber cables 13a-13j. The level correction device 18 is connected between the local stations 17c and 17d. The center station 16 outputs signal light containing a pilot carrier to the local station 17a of a next stage through the optical fiber cable 13a. The local station 17a has a function for synthesizing a signal from the previous stage with the carrier taken in by a self-station and outputting signal light to the next stage and the other local stations have the same functions. All the carriers are contained in signal light which the local station 17f of the final stage outputs, and the center station 16 can receive the whole carriers. The level correction device 18 arranged between the local stations corrects each carrier level in the input signals to be constant.

公开(公告)号：JPH06188642A

公开(公告)日：1994-07-08

申请号：JP33988392

申请日：1992-12-21

申请人： NIPPON ELECTRIC ENG

发明人： SUZUKI FUMIO ,  ISHIHARA TADASHI

IPC分类号： H03F1/34 ,  H03F1/42

摘要： PURPOSE:To attain amplification up to a high frequency band stably by inserting a transistor(TR) in cascode connection between an input terminal and a negative feedback amplifier comprising an inverting amplifier and a feedback resistor and driving the TRs at a constant current. CONSTITUTION:An npn TR 6 is in cascode connection between an input terminal 1 and a negative feedback amplifier comprising an inverting amplifier 3 and a feedback resistor 4 and the npn TR 6 is driven at a constant current from a constant current source 5. Thus, when the base current of the npn TR 6 is sufficiently small, a same current as a signal current inputted to the input terminal 1 is supplied from the negative feedback amplifier. Thus, the input impedance is smaller by increasing a current of the constant current source 5 and a high band coverage is obtained by adding a parasitic capacitance to the input terminal 1. Furthermore, a voltage gain of the inverting amplifier 3 is adjusted to cope with deterioration in the band due to the collector parasitic capacitance of the npn TR 6 and the wiring parasitic capacitance.