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1. 发明专利

DE2640805A1 未知
公开(公告)号：DE2640805A1
公开(公告)日：1977-03-17
申请号：DE2640805
申请日：1976-09-10
申请人： HITACHI LTD
发明人： MUKAEMACHI TAKUJI , FUKUSHIMA YUTAKA
IPC分类号： H04M3/30
摘要： A testing system for testing an impedance of a subscriber line by connecting a test circuit to the subscriber line through one of channels in a network including current self-holding semiconductor switching devices, wherein a series circuit of a second channel and a constant current source is connected in parallel with said first-mentioned channel whereby the current self-holding semiconductor switching devices in said first and second channels are kept conductive by said constant current source.

2. 发明专利

CA1054275A SUBSCRIBER LINE TESTING SYSTEM INCLUDING EXCHANGE SEMICONDUCTOR S POINT SWITCHING 未知
公开(公告)号：CA1054275A
公开(公告)日：1979-05-08
申请号：CA260828
申请日：1976-09-09
申请人： HITACHI LTD
发明人： MUKAEMACHI TAKUJI , FUKUSHIMA YUTAKA
IPC分类号： H04M3/30 , H04B3/46 , H04M1/24
摘要： A testing system for testing an impedance of subscriber line by connecting a test circuit to the subscriber line through one of channels in a network including current self-holding semiconductor switching devices, wherein a series circuit of a second channel and a constant current source is connected in parallel with said first-mentioned channel whereby the current self-holding semiconductor switching device in said first and second channels are kept conductive by said constant current source.

3. 发明专利

JP2002101065A HIGH-SPEED DATA TRANSMISSION METHOD AND REMOTE TERMINATOR 失效
公开(公告)号：JP2002101065A
公开(公告)日：2002-04-05
申请号：JP2000295450
申请日：2000-09-25
申请人： HITACHI LTD
发明人： NAGUMO KATSUMI , NISHI YUMIKO , FUKUSHIMA YUTAKA , YAMAMOTO KOHEI
IPC分类号： H04J3/00 , H04J3/16 , H04L12/66 , H04M3/00 , H04Q11/04
摘要： PROBLEM TO BE SOLVED: To simultaneously transmit a high-speed data subscriber's data call and a telephone subscriber's exchange call, on a pair of optical cables between a housing device and a remote terminator. SOLUTION: In a high-speed data transmission method, for a high-speed data subscriber's 20 data call 92 which is under the control of a remote terminator 3 connected to a housing device 4 via an optical cable 8, a fixed band other than that for a telephone subscriber's 1 exchange call 91 is allocated in the remote terminator 3 so that the data call 92 and the exchange call 91 can be STM-multiplexed and collected in the housing device 4 by the pair of optical cables 8.

4. 发明专利

JPH07312773A PORTABLE TELEPHONE SYSTEM 失效
公开(公告)号：JPH07312773A
公开(公告)日：1995-11-28
申请号：JP15901394
申请日：1994-07-11
申请人： HITACHI LTD , KOKUSAI ELECTRIC CO LTD
发明人： FUKUSHIMA YUTAKA , TAKEMURA TETSUO , IWAKI SHINICHI , HASHIDA MITSUYOSHI , WANAMI MASAO , SHINPO ISAO , WADA MITSUHIRO , UTAKI HIROSHI , KONDOU YOSHIHIRO , YAMAMOTO YOSHINOBU , NAKAKOSHI ARATA , WATABE YUMIKO , OTA KOICHI , KUWABARA HIROSHI
IPC分类号： H04B10/00 , H04B10/032 , H04B10/2507 , H04B10/272 , H04W56/00 , H04W76/02 , H04W84/10 , H04W88/14 , H04W92/00 , H04Q7/22 , H04Q7/24 , H04Q7/26 , H04Q7/30 , H04Q7/38
摘要： PURPOSE:To prevent the interference among radio base stations without the provision of a special physical transmission line and to improve the reliability of the system. CONSTITUTION:A base station controller 3 and a radio base station 2 as to each system are interconnected by optical fibers in duplicate. The optical fibers in duplicate are connected to each radio base station 2 of a concerned system via a star coupler. Then each radio base station 2 is arranged to each zone so that radio base stations of different systems are adjacent to each other. The interface between the base station controller 3 and the radio base station 2 is an I interface and each radio base station 2 makes ping-pong transmission with a portable telephone set synchronously with a multi-frame built in the I interface.

5. 发明专利

JPH07170567A PORTABLE TELEPHONE SYSTEM 失效
公开(公告)号：JPH07170567A
公开(公告)日：1995-07-04
申请号：JP15901494
申请日：1994-07-11
申请人： HITACHI LTD , KOKUSAI ELECTRIC CO LTD
发明人： FUKUSHIMA YUTAKA , TAKEMURA TETSUO , IWAKI SHINICHI , HASHIDA MITSUYOSHI , WANAMI MASAO , SHINPO ISAO , WADA MITSUHIRO , UTAKI HIROSHI , KONDOU YOSHIHIRO , YAMAMOTO YOSHINOBU , NAKAKOSHI ARATA , WATABE YUMIKO , OTA KOICHI , KUWABARA HIROSHI
IPC分类号： H04W24/04 , H04W24/06 , H04W56/00 , H04W60/04 , H04W64/00 , H04W84/04 , H04W88/08 , H04Q7/38
摘要： PURPOSE:To allow the system to provide diversified service utilizing portable telephone sets. CONSTITUTION:Data received by a portable telephone set 1 connected to a radio base station 2 connecting to an exchange 4 or the like through a radio channel are given to an error control circuit 270, in which the error of data is corrected and the corrected data are sent to a data terminal equipment 271 connected to the outside of the system via a predetermined interface. On the other hand, data sent from a data terminal equipment through a predetermined interface are sent from the portable telephone set 1 to the radio base station 2. For example, let the data terminal equipment 271 be a home security equipment, then the home security equipment is controlled from a visiting location and also makes a call to a portable telephone set carried by the user visiting to any place on a predetermined opportunity and required information or the like to the user.

6. 发明专利

JPH07170560A PORTABLE TELEPHONE SYSTEM 失效
公开(公告)号：JPH07170560A
公开(公告)日：1995-07-04
申请号：JP15901694
申请日：1994-07-11
申请人： HITACHI LTD , KOKUSAI ELECTRIC CO LTD
发明人： FUKUSHIMA YUTAKA , TAKEMURA TETSUO , IWAKI SHINICHI , HASHIDA MITSUYOSHI , WANAMI MASAO , SHINPO ISAO , WADA MITSUHIRO , UTAKI HIROSHI , KONDOU YOSHIHIRO , YAMAMOTO YOSHINOBU , NAKAKOSHI ARATA , WATABE YUMIKO , OTA KOICHI , KUWABARA HIROSHI
IPC分类号： H04W24/00 , H04W76/02 , H04W88/14 , H04Q7/22 , H04Q7/24 , H04Q7/26 , H04Q7/30 , H04Q7/34 , H04Q7/38
摘要： PURPOSE:To test a portable telephone system effciently. CONSTITUTION:Upon the receipt of a command from a test operation system Ops, a supervisory test system reserves relay using a designated channel for a test call to a radio base station BS being a test object through an ISDN exchange and gives a command of call of a test call to a test device TTR provided to a specific BS among plural base stations. The test call is connected to the supervisory test system via the BS accepting the reservation. The supervisory test system confirms the normality of the connected call.

7. 发明专利

JPH0698367A RESTRICTION SYSTEM IN MOBILE COMMUNICATION SYSTEM 失效
公开(公告)号：JPH0698367A
公开(公告)日：1994-04-08
申请号：JP30592391
申请日：1991-11-21
申请人： HITACHI LTD
发明人： HASHIDA MITSUYOSHI , FUKUSHIMA YUTAKA , SHINPO ISAO
IPC分类号： H04W4/16 , H04W48/02 , H04W48/20 , H04W84/10 , H04Q7/04
摘要： PURPOSE:To provide the restriction system in the mobile body communication system in which an invalid call in a communication network is reduced and the restriction for each terminal equipment is attained. CONSTITUTION:A restriction status of a terminal equipment is recognized by using a database comprising a terminal equipment position information table representing a location of a terminal equipment 1 and a position restriction information table 20 representing the restriction state at each position to restrict a calling from the terminal equipment and an incoming call to the terminal equipment. Moreover, the registration means together with the position information of the terminal equipment 1 is stored in the table 20, and the call connection request from a terminal equipment making its position registration by an automatic position registration means is made a restriction object with priority over the call connection request from the terminal equipment making position registration by a manual position registration means.

8. 发明专利

JPH01305623A PHASE SYNCHRONOUS OSCILLATOR 失效
公开(公告)号：JPH01305623A
公开(公告)日：1989-12-08
申请号：JP13548688
申请日：1988-06-03
申请人： HITACHI LTD
发明人： SUZUKI SHINJI , FUKUSHIMA YUTAKA , SHIMIZU TAKEHIKO
IPC分类号： H03L7/093 , H03L7/08
摘要： PURPOSE:To reduce the fluctuation of a normal phase error due to the dispersion of parts or the change of an environment and to obtain the phase synchronous oscillator of high stability by providing an amplitude limit element in the input part of a loop filter. CONSTITUTION:Amplitude limit elements 21 and 22 such as a diode, etc., to limit the amplitude of an input voltage to a constant value are provided in the input part of a loop filter 2A. Accordingly, even when the amplitude of an output differential voltage in a phase comparator 1 is fluctuated, since the input differential voltage of the loop filter 2A is limited to the constant amplitude value, the fluctuation of the output differential voltage to accompany the characteristic change of the phase comparator 1 is absorbed and the phase- voltage converting gain of the phase comparator 1 can be suppressed to the constant value. Thus, the fluctuation of the normal phase error, which is caused by the dispersion of the parts and the change of the environment such as a temperature and a power source voltage, etc., can be made small and the phase synchronous oscillator of the high stability can be obtained.

9. 发明专利

JPS6489619A PHASE LOCKED LOOP OSCILLATOR 失效
公开(公告)号：JPS6489619A
公开(公告)日：1989-04-04
申请号：JP24373487
申请日：1987-09-30
申请人： HITACHI LTD
发明人： TAKAHASHI YASUSHI , MAEDA MINORU , FUKUSHIMA YUTAKA
IPC分类号： H03L7/08 , H03L7/06 , H03L7/14
摘要： PURPOSE:To suppress the accumulation of output phase fluctuation by providing a means to measure a time, in which the fluctuation of the central frequency of a phase locked loop oscillator goes to be the integer-fold output frequency control resolution, and a means to detect a control value, in which an output frequency goes to be higher than an input reference clock frequency, and a control value in which it goes to be lower. CONSTITUTION:This device is composed ot a phase comparator 1, a processing circuit 2, a rubidium optical transmitter 3 and a phase locked loop oscillator 4. In this constitution, a phase difference between a reference input clock fin and an output clock fo is detected by the phase comparator 1 and the processing circuit 2 calculates the control value from the detected result. The output clock fo is made by a rubidium oscillator 3, which goes to be a reference oscillator at a selftraveling time, and the phase synchronizing oscillator 4 to be synchronized to it. For the phase locked loop oscillator 4, since an output clock frequency is controlled by the above mentioned control value, the output clock fo is synchronized to the rubidium oscillator 3 and the input clock fin.

10. 发明专利

JPS5416908A TIME PULSE RECEIVING CIRUCUIT 失效
公开(公告)号：JPS5416908A
公开(公告)日：1979-02-07
申请号：JP8097977
申请日：1977-07-08
申请人： HITACHI LTD
发明人： FUKUSHIMA YUTAKA
IPC分类号： H04M15/00 , H04Q1/30 , H04Q1/36
摘要： PURPOSE:To ensure an accurate reception of the periodic pulse by carrying out a sampling with use of the pulse which does not synchronize unnecessarily with the periodic pulse.

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