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71. 发明专利

JP3349985B2 失效
公开(公告)号：JP3349985B2
公开(公告)日：2002-11-25
申请号：JP13829199
申请日：1999-05-19
IPC分类号： H03L7/095 , H04B1/26 , H04L27/227 , H04L27/32

72. 发明专利

JP2002528996A 失效
公开(公告)号：JP2002528996A
公开(公告)日：2002-09-03
申请号：JP2000578924
申请日：1998-10-26
IPC分类号： H04L27/32 , H04B7/005 , H04B7/26 , H04J13/00 , H04L25/02

73. 发明专利

JP2002141960A MOBILE COMMUNICATION DEVICE AND METHOD EMPLOYING CARRIER RECYCLE SYSTEM 审中-公开
公开(公告)号：JP2002141960A
公开(公告)日：2002-05-17
申请号：JP2001254064
申请日：2001-08-24
申请人： SAMSUNG SDS CO LTD
发明人： HO WAN-CHOL , CHOI SEUNG-HO
IPC分类号： H04L27/02 , H04B7/26 , H04L27/18 , H04L27/32
摘要： PROBLEM TO BE SOLVED: To provide a communication unit employing a carrier recycle system and its method. SOLUTION: A mobile station includes a mobile station source coding section 103 that conducts self synchronization Manchester coding, a first modulation section 105 that applies QPSK modulation to a first carrier, a second modulation section 107 that applies ASK modulation to a second carrier to generate an upward modulated signal, and a second demodulation section 113 that demodulates a downward modulated signal received from a base station to extract the second carrier. High-speed data communication is attained by the self-synchronization Manchester coding while other data pattern for frame synchronization is not needed. Furthermore, since the carrier received from the base station is reused and other oscillators are not required for the mobile station, configuration of the hardware is simplified and cost can be reduced.

74. 发明专利

JP2002051090A VARIABLE TRANSMISSION RATE SIGNAL DEMODULATING PROCESSING CIRCUIT 失效
公开(公告)号：JP2002051090A
公开(公告)日：2002-02-15
申请号：JP2000235070
申请日：2000-08-03
申请人： NIPPON ELECTRIC ENG
发明人： YONEDA MASAYOSHI
IPC分类号： H04L27/18 , H04L27/00 , H04L27/32 , H04L27/38
摘要： PROBLEM TO BE SOLVED: To provide a demodulating processing circuit capable of uniformly suppressing a deterioration quantity to a minimum, regardless of a data rate, while avoiding a quantization deterioration caused by a level fluctuation when performing demodulating processing to the IF signal of a gain controlled to almost fix the receiving level of an RF signal on a certain fixed frequency band width in the communication of a data signal having a variable data rate. SOLUTION: When converting an IF signal 1 to a baseband signal, A/D converting that signal and demodulating it, filtering processing corresponding to the rate of a received signal is performed by a switch 5 and an LPF 6. The receiving levels of a carrier C and a noise N in this filter output are corrected by a variable attenuator 7 and an amplifier 8 so as to almost fix the sum of these levels regardless of the rate. Thus, no difference is generated by the rate in the sum of receiving powers of C and N inputted to an A/D converter 9 and the sufficient number of quantized bits in respect to a carrier component is prevented from being not secured in the saturating operation or digital demodulating processing of the A/D converter.

75. 发明专利

JP2001307162A ON-VEHICLE EQUIPMENT 失效
公开(公告)号：JP2001307162A
公开(公告)日：2001-11-02
申请号：JP2000126867
申请日：2000-04-27
申请人： MITSUBISHI HEAVY IND LTD
发明人： KATO MASAKI , MORISHITA KEIICHI , MAEDA TAKASHI
IPC分类号： G07B15/00 , H04L27/06 , H04L27/227 , H04L27/32
摘要： PROBLEM TO BE SOLVED: To provide an on-vehicle equipment which can perform high-speed communication, can be used for ETC and can set a communication area flexibly in accordance with each application. SOLUTION: The on-vehicle equipment is provided with a transmitter for transmitting first transmission data to a roadside equipment by modulating it by an ASK modulator and transmitting second transmission data to another roadside equipment by modulating it by a PSK modulator, and a receiver which obtains ASK demodulated data (j) by demodulating an ASK modulation wave (h), which is transmitted from the roadside equipment, by an ASK demodulator 51 and obtains PSK demodulation data (k) by demodulating a PSK modulation wave (i) transmitted from another roadside equipment by a phase demodulator constituted so as to multiply a PSK carrier (p), which is reproduced by a carrier reproduction circuit 45, and a PSK demodulation wave (n) by a PSK detector 49. Furthermore, the on-vehicle equipment is provided with a receiving sensitivity switching circuit 50 for switching receiving sensitivity to the wave (i) and the wave (h) for each application.

76. 发明专利

JP2001274856A TRANSMITTER AND RECEIVER 失效
公开(公告)号：JP2001274856A
公开(公告)日：2001-10-05
申请号：JP2000088505
申请日：2000-03-24
申请人： HITACHI LTD
发明人： NODA MASAKI , NODA TSUTOMU , ADACHI SATOSHI , WADA KENJI , YOKOUCHI KATSUMASA
IPC分类号： H04N5/40 , H04J3/00 , H04L27/10 , H04L27/32 , H04L27/34 , H04N5/455 , H04N5/46 , H04N7/08 , H04N7/081 , H04N7/24 , H04N19/00
摘要： PROBLEM TO BE SOLVED: To provide a method and a device for stably receiving BS digital broadcast in which a transport stream having a frame configuration and transmission multiple control information showing a modulation method in a frame and a transport stream configuration are transmitted by using a cable television (CATV) transmission path, etc. SOLUTION: A receiving side can recognize switching timing of hierarchization and also select digital data of a hierarchized transport stream format in which a deteriorated packet is eliminated by transmitting the switching information of the digital data of a transport stream format having hierarchical relationship of the BS digital broadcasting by transmission multiple control information or digital modulated wave such as an FSK and transmitting a packet with the packet masked against deterioration of a high hierarchy.

77. 发明专利

JP3088315B2 失效
公开(公告)号：JP3088315B2
公开(公告)日：2000-09-18
申请号：JP35261796
申请日：1996-12-16
IPC分类号： H03D1/00 , H04J1/00 , H04J9/00 , H04L27/32

78. 发明专利

JP2000081597A OPTICAL DATA TRANSMISSION DEVICE 失效
公开(公告)号：JP2000081597A
公开(公告)日：2000-03-21
申请号：JP20527099
申请日：1999-07-19
申请人： CIT ALCATEL
发明人： PENNINCKX DENIS , BRIDOUX CHRISTOPHE
IPC分类号： G02F1/03 , H04B10/2513 , H04B10/50 , H04B10/564 , H04L27/32 , H04B10/04 , H04B10/06 , H04B10/142 , H04B10/152
摘要： PROBLEM TO BE SOLVED: To provide a transmission device which is improved in the flexibility of use and allows simple optimization relating to a variety of optical links and respective transmission distances. SOLUTION: This device includes first electro-optic modulators 1, 2 which are capable of supplying phase-controlled light signals S having modulation light power between a low level and a high level in response with input electric signals E and are capable of executing phase transition within respective time cells including low level power. The device includes second electro-optic modulators 3, 4 which are controlled by the input electric signals E and are coupled to the first electro-optic modulators 1, 2 in order to improve the flexibility thereof. The phase-controlled light signals are subjected to supplementary modulation of the power and/or phase in order to change an extinction ratio and/or to impart a transition 'chirp' to the signals.

79. 发明专利

JPH11284688A NETWORK COMMUNICATION SYSTEM 失效
公开(公告)号：JPH11284688A
公开(公告)日：1999-10-15
申请号：JP37331798
申请日：1998-12-28
申请人： MITSUBISHI ELECTRIC INF TECH
发明人： POON TOMMY C , BAO JAY , MIZUTANI YOSHIKI , NAKAYAMA HIROYUKI
IPC分类号： H04L27/12 , H04B1/40 , H04J11/00 , H04L1/00 , H04L27/00 , H04L27/02 , H04L27/06 , H04L27/18 , H04L27/20 , H04L27/22 , H04L27/26 , H04L27/32 , H04L27/34 , H04L27/36 , H04L27/38 , H04L29/06 , H04L29/08 , H04L29/10 , H04N5/40 , H04N5/44 , H04N5/455 , H04N5/46 , H04N7/08 , H04N7/081
摘要： PROBLEM TO BE SOLVED: To attain re-configuration for a demodulator and a modulator without increasing the number of demodulators and modulators by detecting a channel parameter and changing a modulation format of sent information according to the detection. SOLUTION: A header is always QPSK-modulated and sent repetitively periodically during transmission of a data signal. A receiver configures itself to the QPSK demodulation mode just after application of power supply, and after detecting a header word exquisitely, the receiver reconfigures itself. After detection of a prescribed noise level, a different modulator type is selected to enhance the reliability of communication. When two devices both using a conventional MODEM come the traffic, a modulator type is switched over depending on detection of any degradation in the communication state. This is conducted by using a channel noise detector 258 connecting with a controller 208 detecting a noise on a channel. Then, the controller 208 designates a proper modulation format, a proper frequency and a proper band width to realize communication with higher reliability.

80. 发明专利

JPH10178405A AM DATA MULTIPLEX MODULATED WAVE SIGNAL DEMODULATION CIRCUIT 失效
公开(公告)号：JPH10178405A
公开(公告)日：1998-06-30
申请号：JP35261796
申请日：1996-12-16
申请人： KENWOOD CORP
发明人： SHINODA ATSUSHI
IPC分类号： H03D1/00 , H04J1/00 , H04J9/00 , H04L27/32
摘要： PROBLEM TO BE SOLVED: To provide an AM data multiplex modulated wave signal demodulation circuit that demodulates a base band digital signal from an AM data multiplex modulation signal based on a multiplexed digital modulation wave signal. SOLUTION: The demodulation circuit uses an Am modulator to amplitude- modulate a carrier whose frequency is fc with an analog signal wave and demodulates a base band digital signal from an AM data multiplex modulated wave signal in which a digital modulated wave signal is multiplexed at a position of a frequency (fc+fα) and at a position of a frequency (fc-fα) in axial symmetry on a frequency base. In this case, the AM data multiplex modulated wave signal is sampled at a position at which a level of the carrier is zero, the sampled signal is A/D-converted by an A/D converter 4 and the A/D converted discrete output signal is orthogonally detected at a orthogonal detector 6 by using two carrier wave signals orthogonal to each other whose frequency is fα, a high frequency component of an orthogonal detection output is eliminated by a low-pass filter 7 to demodulate a base band digital signal.

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