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1. 发明专利

JPS59224907A DIGITAL CONTROL TYPE AGC CIRCUIT 失效
公开(公告)号：JPS59224907A
公开(公告)日：1984-12-17
申请号：JP9945683
申请日：1983-06-06
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE , NIPPON ELECTRIC CO
发明人： NAKAJIYOU TAKAFUMI , TSUDA TOSHITAKA , YAMAGUCHI KAZUO , FUKUDA SETSU , ISHIKAWA MASAYUKI , TAMAKI NORIO , KURAISHI YOSHIAKI
IPC分类号： H04B3/04 , H03G3/20 , H04B3/06
摘要： PURPOSE:To solve simultaneously delay in initial locking of AGC, inconvenience in mounting of capacitor and instability of AGC characteristic or the like by searching the optimum AGC level depending on the pulse mode of an output pulse from two comparators. CONSTITUTION:While the 1st comparator 14-1 and the 2nd comparator 14-2 receive in common an AGC control output signal Sout, they have respectively the 1st reference voltage Vr1 and the 2nd reference voltage Vr2 as a comparison reference voltage Vr1 and the 2nd reference voltage Vr2 as a comparison reference level. The 1st output pulse C1 is obtained during the period when the level of the signal Sout exceeds the Vr1 and the 2nd output pulse C2 is obtained during the period when the level exceeds the Vr2. Both the output pulses C1 and C2 exist in the 1st event I and only the output pulse C2 exists in the 2nd event II. The 1st event I represents that the signal Sout does not go down up to a prescribed level yet and the further reduction is required for the gain. Further, the 2nd event II represents that the signal Sout goes down to the prescribed level for a moment and no further reduction in the gain is required.

2. 发明专利

JPS607240A TIMING EXTRACTING CIRCUIT 失效
公开(公告)号：JPS607240A
公开(公告)日：1985-01-16
申请号：JP11395183
申请日：1983-06-24
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： NAKAJIYOU TAKAFUMI , TSUDA TOSHITAKA , YAMAGUCHI KAZUO , FUKUDA SETSU , ISHIKAWA MASAYUKI , TAMAKI NORIO
IPC分类号： H04L25/52 , H03G11/00 , H04L7/027 , H04L25/06 , H04L7/02
摘要： PURPOSE:To prevent the fluctuation of a slice level from being caused even if the characteristic of an active element is varied by supervising the output of an equalizing amplifier, and slicing the output by applying the linear amplification when the output is at the reference slice level or over, and holding the value equal to the slice level when the output is at the reference slice level or below. CONSTITUTION:A nonlinear amplifier 14 consists of a linear amplifier (amplifier and switch circuit) 24 and a comparator 26. The amplifier 24 amplifies linearly an input signal when an input signal S3 is higher than the slice level, and has a characteristic holding an amplifier output voltage at a level equal to the slice level when the input signal is lower, and the comparator 26 receives the input signal S3 and a voltage VB for deciding slice level from a reference voltage source 20 and executes the changeover control for the amplifier 24. Differential pair transistors (TRs) 32, 34 flow an equal current when S3=SB. The comparator 26 changes over a switch 42 in the position of the contact (b) when S3 VB and an output at S3=VB is held when S3

3. 发明专利

JPS605633A BRIDGED TAP EQUALIZER 失效
公开(公告)号：JPS605633A
公开(公告)日：1985-01-12
申请号：JP11334083
申请日：1983-06-23
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： TSUDA TOSHITAKA , YAMAGUCHI KAZUO , NAKAJIYOU TAKAFUMI , FUKUDA SETSU , ISHIKAWA MASAYUKI , TAMAKI NORIO
IPC分类号： H03H15/00 , H04B3/04 , H04B3/06 , H04L25/03
摘要： PURPOSE:To equalize at high stability in relatively short time by detecting arrival of a pulse signal at equalizer input and controlling an inhibition gate by output that delayed the detection pulse one step. CONSTITUTION:An equalizer output signal is delayed by plural steps of delay cicrcuits D1-D3 through an inhibition gate IHG. Delayed output of each step is multiplied by coefficients C1-C3 by multipliers M1-M3 respectively, and output of multipliers M1-M3 is subtracted from an input signal IN by an arithmetic circuit SM to obtain output of a bridged tap equalizer. When the input signal of the equalizer is pulselike form, this is delayed by the time 1T for a time slot by the circuit D1, and this is detected by a pulse detecting circuit PD. The detected pulse is waveform shaped by a time constant circuit TC, and a gate IHG is controlled by the signal, and the pulse to be inputted next is inhibited by IHG. Accordingly, no signal due to secondary echo occurs, and action is controlled at high speed.

4. 发明专利

JPS59221127A TIME CONSTANT CIRCUIT 失效
公开(公告)号：JPS59221127A
公开(公告)日：1984-12-12
申请号：JP9658383
申请日：1983-05-31
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： FUKUDA SETSU , TSUDA TOSHITAKA , YAMAGUCHI KAZUO , NAKAJIYOU TAKAFUMI , KIMURA TADAKATSU , TAMAKI NORIO
IPC分类号： H03H21/00 , H04B3/04 , H04B3/06 , H04L25/03
摘要： PURPOSE:To apply coefficient correction only to a stationary equalizing error by utilizing a difference between a tap coefficient correcting signal at steady-state and a correcting signal produced suddenly in a tap coefficient control circuit of an automatic equalizer. CONSTITUTION:An FF2, an FF3 and an EOR gate C constitute a circuit discriminating whether the tap coefficient correcting signal is of the same polarity or opposite polarity, and if the signal is inputted continuously, an output of the EOR gate C is at ''0'' and when the polarity is opposite, the output is at ''1''. When the output is at ''1'', a continuous number counter H is reset by an FF4 and a gate G and also an NAND gate D and an AND gate A revise the coefficient of an equalizer (not shown). When an output of the EOR gate C is at ''0'', the continuous number cunter H counts the continuous number by the Q' output of the FF4 and when the count value reaches a prescribed number, the coefficient of the equalizer is revised by the output of the AND gate F and the Q output of the FF1 resets the counter H.

5. 发明专利

JP2001251615A OPTICAL TERMINATOR FOR DISTRIBUTING VIDEO 失效
公开(公告)号：JP2001251615A
公开(公告)日：2001-09-14
申请号：JP2000062112
申请日：2000-03-07
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： SUGAWA TOMONORI , UENOHARA HIROYUKI , TAMAKI NORIO
IPC分类号： H04M11/00 , H04N5/00 , H04N5/44 , H04N7/173 , H04N7/22 , H04N21/438
摘要： PROBLEM TO BE SOLVED: To eliminate the need for a set-top box for every television receiver. SOLUTION: In a service system an integrated service of a video distribution service, a data communication service and a phone service is provided through an optical fiber, the optical terminator for distributing video image installed in a house being distribution destination has a video ONU 27 that converts a video signal of a plurality of channels provided through the optical fiber into an electric signal and tuner means 32-37 that select one channel or more from the video signal converted by the video ONU 27 and transmit the video signal of the selected channel(s) to one image device or more installed in the house.

6. 发明专利

JPH10232326A LIGHT TRANSMITTING DEVICE 失效
公开(公告)号：JPH10232326A
公开(公告)日：1998-09-02
申请号：JP3796497
申请日：1997-02-21
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： TAMAKI NORIO , MIKI NORIMOTO , HASHIMOTO HITOSHI , HAGA KAZUO
IPC分类号： G02B6/42 , G02B6/28 , H04B10/00 , H04B10/27 , H04B10/272 , H04J14/08 , H04B10/20 , H04B10/24
摘要： PROBLEM TO BE SOLVED: To make possible ideally making a station side loss zero and transferring only with a subscriber side loss increase by connecting a transmitting element to a receiving element with a specified branch coupler. SOLUTION: A transmitting unit 21 having the transmitting element LD as an optical module and a receiving unit 22 having the receiving element PD are respectively connected to one side two output ends among four output ends of a 2×2 branch coupler 24. Further, the other two output ends of the 2×2 branch coupler 24 are connected respectively to optical star couplers through optical fibers. Further, the 2×2 branch coupler 24 is formed on a planer light wave circuit(PLC). By connecting with this X branch coupler, a branch loss 3dB in the station side is made zero ideally compared with being connected with a Y branch coupler, and the transmission becomes possible only with the subscriber side loss of 3dB. Thus, the matter that a transmission distance of a subscriber line is prolonged becomes possible.

7. 发明专利

JPS6376536A CIRCUIT FOR EXTRACTING TIMING OF BINARY CODE 失效
公开(公告)号：JPS6376536A
公开(公告)日：1988-04-06
申请号：JP21969786
申请日：1986-09-19
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： TAMAKI NORIO , MANO FUMIO
IPC分类号： H04L7/027 , H04L7/02 , H04L25/40
摘要： PURPOSE:To make normal timing extraction possible even in a transmission system, in which inter-symbol interference exists, by providing a delaying circuit which delays a sampled output by one period, circuit which discriminates the polarity of a sample signal, circuit which compares amplitude of signals with each other, and oscillator and giving the timing extracted by means of the output of the oscillator. CONSTITUTION:An EX-OR 104 detects that a received code and a signal which is produced by delaying the received code by one bit have the same polarity (positive and positive or negative and negative) and, only when they have the same polarity, actuates this binary code timing extracting circuit. A subtraction circuit 107 detects the difference between the received signal and its one-bit delayed code, namely, the amplitude difference and a code bit detector 108 detects the polarity (positive or negative) of the amplitude point. Then the polarity of the amplitude difference is controlled in accordance with the polarity of the received code detected at an AND circuit 105. When control is performed to take the absolute value of the amplitude difference by detecting the polarity of the received code in such way, the advance or delay of a timing phase can be detected and, therefore, the timing phase can be adjusted by controlling the phase of a VCO-112.

8. 发明专利

JPH10233734A OPTICAL TRANSMISSION SYSTEM 失效
公开(公告)号：JPH10233734A
公开(公告)日：1998-09-02
申请号：JP3795797
申请日：1997-02-21
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： TAMAKI NORIO , MIKI NORIMOTO , HAGA KAZUO
IPC分类号： H04J14/08 , H04B10/2507 , H04B10/27 , H04B10/272 , H04B10/02 , H04B10/18 , H04B10/20
摘要： PROBLEM TO BE SOLVED: To prevent erroneous synchronism due to reflected light in a transmission system by which one station-side device and plural subscriber-side devices execute point/multi-point optical transmission by setting guard time so that the first reflected light of an optical transmission signal from the assumed farthest reflection terminal is not superposed on a reception signal. SOLUTION: The station-side device is provided with a switch 21 for changing over transmission and reception and a guard time generation circuit for setting transition time and reception time. The subscriber-side device is provided with a switch 41 for changing over transmission and reception and a guard time generation circuit 48 for setting guard time between reception time and transmission time. Then, guard time between a transmission time area and a reception time area is set at a time interval where the first reflected light of the light transmission signal from the assumed remotest reflection terminal is not superposed on the reception signal, and the switching of the transmission/reception of the switches 21 and 41 is controlled. Thus, the reception signal and a bit for reception distance measurement are not affected even if reflection at a connection terminal is generated in any way.

9. 发明专利

JPH09214436A OPTICAL TRAMSMITTER 失效
公开(公告)号：JPH09214436A
公开(公告)日：1997-08-15
申请号：JP1784996
申请日：1996-02-02
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： IKEDA SATOSHI , KIKUSHIMA KOJI , KUMOSAKI KIYOMI , TAMAKI NORIO , SHIBATA NOBURU
IPC分类号： H04B10/00 , H04B10/25 , H04B10/2507 , H04B10/516 , H04B10/548 , H04B10/58 , H04B10/61 , H04J14/00 , H04J14/02 , H04J14/04 , H04J14/06 , H04B10/152 , H04B10/02 , H04B10/04 , H04B10/06 , H04B10/142 , H04B10/18
摘要： PROBLEM TO BE SOLVED: To simultaneously transmit an AM modulation signal which is frequency-multiplexed and the other signal at low cost by setting a difference between the center frequencies of a local oscillation light and a light signal which is frequency-modulated to be larger than the sum of the half value of the occupied frequency bandwidth of the light signal which is frequency-modulated and the occupied frequency bandwidth of a signal different from the light signal. SOLUTION: A collective FM modulator 3 is provided with an optical frequency modulation part 31, an optical frequency local oscillation part 32, an optical multiplexing part 33 and an optical heterodyne detection part 34. The difference between the center optical frequencies of local oscillation light and the light signal which is frequency-modulated is set to be larger than the sum of the half value of the occupied frequency bandwidth of the frequency-modulated light signal and the occupied frequency band of the second signal different from the frequency modulated light signal. The signal can be multiplexed without being overlapped with the second signal by setting the intermediate frequency of batch frequency modulation to be larger than a value obtained by adding the occupied frequency bandwidth of the second signal to the half value of the occupied frequency bandwidth of the batch FM video signal. Thus, the AM modulation signal and the other signal can simultaneously be transmitted.

10. 发明专利

JPH10233747A SUBSCRIBER LINE TRANSMITTING SYSTEM 失效
公开(公告)号：JPH10233747A
公开(公告)日：1998-09-02
申请号：JP3793597
申请日：1997-02-21
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： TAMAKI NORIO , HAGA KAZUO , MIKI NORIMOTO
IPC分类号： H04J14/00 , H04B10/00 , H04B10/2507 , H04B10/27 , H04B10/272 , H04J3/00 , H04J14/04 , H04J14/06 , H04B10/20 , H04B10/24
摘要： PROBLEM TO BE SOLVED: To shorten the processing time of a reception frame and to shorten transmission delay by dividing the transmission frame of a down signal into two, arranging the first half part of information addressed to a subscriber device, arranging the latter half part of information, dividing an up signal into two and similarly arranging them. SOLUTION: A station-side device transmits the first half parts of information signals (signal 501-1 to signal 502-1) addressed to the respective subscriber devices by following an overhead part in frame areas divided into a first half and a latter half. Then, it transmits the latter half parts of the information signals (signal 501-2 to signal 502-2) addressed to the subscriber devices. A subscriber-side device transmits the first half parts of the up signals (signal 511-1 ... signal 512-1) to the station-side device at the first half of the up frame area, and the first half parts of the up signals (signal 511-2 ... signal 512-2) to the station-side device at the latter half of the down frame area at timing allocated to the subscriber-side devices.

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