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71. 发明专利

JPH03272233A INTER-CARRIER PHASE SYNCHRONIZING SYSTEM 失效
公开(公告)号：JPH03272233A
公开(公告)日：1991-12-03
申请号：JP7239890
申请日：1990-03-20
申请人： FUJITSU LTD
发明人： AONO YOSHITAMI , IWAMATSU TAKANORI
IPC分类号： H04L27/36 , H04L7/00
摘要： PURPOSE:To establish the synchronization between carriers by stopping tentatively an input clock to a device receiving other than reference carrier with respect to phase synchronizing step-out between clocks controlling write/read. CONSTITUTION:A data speed conversion section 10 and an overhead bit insertion section 19 are provided on a data transmitter side corresponding to each carrier. Moreover, the data speed conversion section 10 is provided with a tentative storage memory 11 for input data, a write address generating section 13 and a read address generating section 12. An extraction section 14 extracts an output frame pulse from the inputted data. A comparison section 15 compares the phases of clocks corresponding to carriers and a comparison section 16 compares extracted output clock pulses. When asynchronization is detected for the prescribed number of times or above, the input clock is tentatively stopped to take the phase synchronization between carriers.

72. 发明专利

JPH0396039A CARRIER RECOVERY CIRCUIT 失效
公开(公告)号：JPH0396039A
公开(公告)日：1991-04-22
申请号：JP23202989
申请日：1989-09-07
申请人： FUJITSU LTD
发明人： IWAMATSU TAKANORI , AONO YOSHITAMI
IPC分类号： H04L27/38
摘要： PURPOSE:To widen a pull-in enable frequency range further and to lock a recovered carrier with a fast rotating speed by demodulating a multi-value orthogonal amplitude signal from an input signal with recovered carriers whose phases differ by 90 deg.. CONSTITUTION:A demodulation means 1 demodulates a multi-value orthogonal amplitude signal from an input signal with a recovered carrier to output a demodulation signal. A phase synchronization means 2 corrects the phase of a recovered carrier based on the information representing the rotating direction of the phase with respect to a reference signal point on a reference phase plane of the demodulation signal obtained precedingly and gives the result to the demodulation means 1. A control means 3 prior to carrier pull-in obtains the information representing the rotating direction of the recovered carrier from the relation of phase at two different point of time of the reference signal point at a corner of the reference phase plane based on the demodulation signal and outputs it to the phase synchronization means 2.

73. 发明专利

JPH0284834A INTER-CROSS POLARIZATION INTERFERENCE COMPENSATOR 失效
公开(公告)号：JPH0284834A
公开(公告)日：1990-03-26
申请号：JP23602188
申请日：1988-09-20
申请人： FUJITSU LTD
发明人： AONO YOSHITAMI , IWAMATSU TAKANORI
IPC分类号： H04L27/38 , H04J11/00
摘要： PURPOSE:To prevent inter-cross polarization interference compensating capacity from being lowered and to operate a device at code speed by compensating delay difference between a main polarization and a cross polarization being generated due to fading on a transmission path, etc., adaptively and providing a phase control circuit, etc. CONSTITUTION:A cross polarization demodulation circuit 41 identifies and demodulates the signal of inputted cross polarization, and a clock generation circuit 42 generates a clock to be used in the decision of the timing of signal identification at the circuit 41. Also, the phase control circuit 45 judges the direction of the phase of a timing clock to obtain the optimum interference compensation effect by adjusting in a direction to lead or lag based on relation between the error of a main polarization demodulation signal before applying interference compensation and the inclination of a compensation signal. Then, the phase of the timing clock supplied from the circuit 42 to the circuit 41 is adjusted in a direction of judged result. In such a way, the compensation signal is generated at a compensation signal generation circuit 43 based on the demodulation signal whose identification timing is set at the optimum level, and the inter-cross polarization interference compensation capacity can be prevented from being lowered by suppressing an interference signal, in the main polarization by using the compensation signal, and also, the device can be operated at the code speed.

74. 发明专利

JPH01317043A DIGITAL COMPARATOR 失效
公开(公告)号：JPH01317043A
公开(公告)日：1989-12-21
申请号：JP14867388
申请日：1988-06-16
申请人： FUJITSU LTD
发明人： IWAMATSU TAKANORI
IPC分类号： G06F7/02 , G01R29/02 , H03K5/01 , H03K5/1252 , H04J3/14 , H04L1/00
摘要： PURPOSE:To facilitate circuit integration and to attain fast discrimination by discriminating whether or not a count of an up/down counting means counting up at a data with a prescribed level and counting down by an output of a frequency divider means is larger than a predetermined threshold value. CONSTITUTION:A clock extracted from a data is subject to t1/t2 frequency division by a frequency divider means 2, that is, multiplied by t2/t1, the result is given to a down terminal D of the up/down counting means 3 and the data is fed to an up terminal U as it is respectively. When 1s in the data shares the time t2 during the time t1, the count of the up/down count means 3 is all '1' and when the data is less conversely, the count is all '0'. Then a discriminator 4 compares whether the count of the up/down counting means 3 is more than the predetermined threshold value or less and sends the result of discrimination. Thus, circuit integration is facilitated and the result of discrimination is obtained quickly.

75. 发明专利

JPH01158854A DEMODULATOR FOR DIGITAL RADIO COMMUNICATION SYSTEM 失效
公开(公告)号：JPH01158854A
公开(公告)日：1989-06-21
申请号：JP31689787
申请日：1987-12-15
申请人： FUJITSU LTD
发明人： AONO YOSHITAMI , IWAMATSU TAKANORI
IPC分类号： H04L27/38 , H04L27/00
摘要： PURPOSE:To attain stable operation by providing an automatic phase control circuit detecting a phase difference between a digital data and a fixed frequency signal and applying coordinate conversion corresponding to the phase difference thereby improving the temperature stability. CONSTITUTION:An IF signal is branched and converted into a base band signal by orthogonal detectors 1a, 1b respectively and converted into a digital signal via filters 4a, 4b and an identification device 5. The phase of the IF signal is normally deviated from the phase of an oscillated frequency signal from a crystal oscillator 2. The automatic phase control circuit 6 detects the phase difference and applies the coordinate conversion with respect to the phase difference (concretely, the two inputs are corrected by control information sin thetaand costheta, where theta is the phase difference) to obtain correct I and Q channel signals. The fixed frequency is used for the detection to correct the phase difference. Thus, the temperature stability is improved and the synchronizing lock range is widened.

76. 发明专利

JPS6460133A CONTROL CIRCUIT FOR LOW FREQUENCY COMPONENT SUPPRESSION INTEGRATING VALUE 失效
公开(公告)号：JPS6460133A
公开(公告)日：1989-03-07
申请号：JP21742187
申请日：1987-08-31
申请人： FUJITSU LTD
发明人： FUKUDA EISUKE , YAMAGISHI MICHINAGA , AONO YOSHITAMI , MINOWA MORIHIKO , IWAMATSU TAKANORI , TAKENAKA SADAO
IPC分类号： H04L27/34 , H04L25/49 , H04L27/00
摘要： PURPOSE:To obtain a control means for low frequency suppression integrating value for facilitating the reproduction of a pilot carrier by adopting a modulating system to cause a space-arranged signal point to be unsymmetrical to the component axis or to cause a code allocation to the signal point not to be an inversion relation related to the component axis. CONSTITUTION:In-phase component data Iin and orthogonal component data Qin to be modulated are converted to corresponding component values (x) and (y) of a coordinates system for converting a code absolute value by a converting part 4 for the polarity deciding system. The components (x) and (y) are used for generating the sum for one frame at linear frame integration arithmetic circuits 6x and 6y, and for respective sums, polarity signals are outputted from polarity deciding circuits 8x and 8y. The polarity signal for converting the code absolute value is used for converting the I and Q components from one frame delaying parts 2I and 2Q by a code converting part 10. For frame outputs from the code converting part 10, a code converting flag is inserted to the frame slot by a flag inserting part 12. Thus, the low frequency component suppression integrating value control circuit to suppress a low frequency component can be obtained.

77. 发明专利

JPS64845A COMMUNICATION SYSTEM FOR MULTILEVEL AMPLITUDE MODULATING AND DEMODULATING SYSTEM 失效
公开(公告)号：JPS64845A
公开(公告)日：1989-01-05
申请号：JP3539188
申请日：1988-02-19
申请人： FUJITSU LTD
发明人： TAKENAKA SADAO , AONO YOSHITAMI , IWAMATSU TAKANORI , MINOWA MORIHIKO , OHORA YOSHIMASA , NAKAMURA HIROSHI
IPC分类号： H04L27/36 , H04L27/00 , H04L27/38
摘要： PURPOSE:To increase the multilevel number and to improve the frequency use rate by converting the signal point arrangement of transmission data from a rectangular grating to a honeycomb in a modulator. CONSTITUTION:The signal point arrangement of in-phase data and quadrature data is converted from a rectangular grating to a honeycomb by a signal point arrangement converting part 101, and data is sent to a transmission line 300 after quadrature amplitude modulation in a quadrature amplitude modulating part 102. A multilevel quadrature amplitude modulated and demodulated QAM is detected by a synchronous detecting part 201 to obtain an in-phase signal Xb and a quadrature signal Yb, and the operation of conversion from rectangular coordinate axes to three coordinate axes connecting signal points adjacent to one another in the honeycomb signal point arrangement is performed by a coordinate transforming part 202 with respect to these signals, and three coordinate transformation output signals X, U, and V corresponding to respective coordinate axes are obtained. Signal points of these output signals X, U, and V are discriminated by a signal discriminating part 203 to output output data corresponing to signal points.

78. 发明专利

JP2003143112A PROPAGATION PATH CHARACTERISTIC ESTIMATION APPARATUS 审中-公开
公开(公告)号：JP2003143112A
公开(公告)日：2003-05-16
申请号：JP2001334040
申请日：2001-10-31
申请人： FUJITSU LTD
发明人： IWAMATSU TAKANORI , AMAZAWA TAIJI
IPC分类号： H04J13/00 , H04L25/02 , H04J13/04
摘要： PROBLEM TO BE SOLVED: To improve estimation information of a propagation path characteristic even in an unknown information section. SOLUTION: In the phase/amplitude characteristic estimation apparatus, first transmission information removing parts (12, 13 and 14) remove transmission information from the received signal of a data channel where already known information is transmitted time-multiplexed between pieces of unknown information and output phase/amplitude information showing phase/amplitude characteristic which the data channel has received at the propagation path. Second transmission information removing parts (16 and 17) remove transmission information from the received signal of the data channel where only unknown information is transmitted and outputs phase/amplitude information showing phase/amplitude characteristic which the data channel has received at the propagation path. An addition part 19 adds the phase/amplitude information outputted from the first and second transmission information removing parts, and a phase/ amplitude estimation part 20 estimates phase characteristic and amplitude characteristic which each channel receive at the propagation path by the output of the addition part.

79. 发明专利

JP2001024560A CORRELATION ENERGY DETECTOR AND ITS DEVICE 失效
公开(公告)号：JP2001024560A
公开(公告)日：2001-01-26
申请号：JP19727099
申请日：1999-07-12
申请人： FUJITSU LTD
发明人： IWAMATSU TAKANORI
IPC分类号： H04L27/20 , H04B1/707 , H04B1/709 , H04B1/7115
摘要： PROBLEM TO BE SOLVED: To attain suitable correlation energy detection and finger (rake) synthesis or the like by simple constitution. SOLUTION: The correlation energy detector for detecting the degree of correlation between a 1st signal series (Ii, Qi) expressed by an I-Q orthogonal component and a 2nd signal series (Hj) is provided with a correlation operation means for finding out each correlation value (Iij, Qij) between the 1st and 2nd signal series and a square sum route operation means for finding out the square sum root √(Iij2+Qij2)} of found correlation values or an absolute value sum operation means for finding out the absolute value sum (|Iij|+|Qij|) of found correlation values. Since the square sum root correlation energy or the absolute value sum correlation energy is adopted as correlation energy instead of conventional square sum correlation energy (Iij2+Qij2), the scale of a circuit can be sharply reduced without reducing maximum value detection accuracy or the like.

80. 发明专利

JP2000174664A DEMODULATION METHOD AND DEVICE IN RADIO COMMUNICATION SYSTEM USING M SEQUENCE QUADRATURE MODULATION 失效
公开(公告)号：JP2000174664A
公开(公告)日：2000-06-23
申请号：JP27850899
申请日：1999-09-30
申请人： FUJITSU LTD
发明人： IWAMATSU TAKANORI , FUKUI MAMORU
IPC分类号： H03M7/30 , H04B1/707 , H04B1/7075 , H04L27/22
摘要： PROBLEM TO BE SOLVED: To provide excellent error rate characteristics equivalent to that of a synchronous system though it is an asynchronous system in a demodulation device in a radio communication system using M sequence quadrature modulation. SOLUTION: This demodulation device is provided with a reliability calculation means 21 for calculating the certainty of the value of each correlation energy as reliability R for the correlation energy for each Walsh number, a correction means 22 for considering the reliability R respectively corresponding to the correlation energy and obtaining corrected correlation energy and a maximum energy selection means 19 for using each obtained corrected correlation energy and selecting maximum correlation energy from them. Signals equivalent to the Walsh number pertinent to the maximum correlation energy are demodulated as reception signals.

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