专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

71. 发明专利

JPS62101132A RADIO COMMUNICATION SYSTEM 失效
公开(公告)号：JPS62101132A
公开(公告)日：1987-05-11
申请号：JP24066885
申请日：1985-10-29
申请人： FUJITSU LTD
发明人： NAKAZAWA ISAO , HACHITSUKA HIROYUKI , DOI YOSHIKAZU
IPC分类号： H04J3/00 , H04B7/04 , H04L1/06 , H04L1/22 , H04L12/28
摘要： PURPOSE:To ensure the excellent communication quality by connecting plural antennas to a node transmitter/receiver, applying communication with a terminal transmitter/receiver by using a burst signal and applying reception processing the burst signal giving the best quality to a reception signal in plural burst signals of the same content. CONSTITUTION:The node transmitter/receiver 1 connected with plural antennas 2 arranged scatteringly on a ceiling 5 indoor, etc., and the terminal transmitter/ receiver 3 having an antenna 4 and arranged on a desk 6 or the like are provided. The burst signal from the node transmitter/receiver 1 is sent from each antenna 2 so as to be overlapped timewise, and the burst signal from the terminal transmitter/receiver 3 is received by each antenna 2 and the burst signal is fed to the node transmitter/receiver 1 so as not to overlap the burst signal timewise. The node transmitter/receiver 1 and the terminal transmitter/receiver 3 detect the reception level of the burst signal and process the reception burst signal having the best quality of the reception signal, e.g., that of the maximum reception level as a reception signal.

72. 发明专利

JPS6248112A DEMODULATION CIRCUIT 失效
公开(公告)号：JPS6248112A
公开(公告)日：1987-03-02
申请号：JP18785485
申请日：1985-08-27
申请人： FUJITSU LTD
发明人： NAKAZAWA ISAO
IPC分类号： H03D3/02 , H03D3/00
摘要： PURPOSE:To simplify the circuit by applying an output of a VCO controlled by a demodulation output signal to a mixer and a phase detector so as to allow the VCO to apply both FM feedback and PLL demodulation. CONSTITUTION:The VCO 11 applies FM feedback and PLL demodulation, the center frequency of an input signal e is suppressed to a half and the deviation of a modulation wave is suppressed to 1/2 of the input by a local signal e from the VCO 11, an output of a BPF 10 is e , which is amplified by a gain variable amplifier 3 and the result is inputted to a phase detector 4, where the phase difference from the signal from the VCO 11 is detected, a demodulation signal is amplified by an amplifier 5 and then outputted and drives the VCO 11 via an LPF 12. The single VCO 11 applies both the FM feedback and the PLL demodulation in this way to apply demodulation where the occupied band width is halved and noise is reduced.

73. 发明专利

JPS6031366B2 失效
公开(公告)号：JPS6031366B2
公开(公告)日：1985-07-22
申请号：JP16144378
申请日：1978-12-28
申请人： FUJITSU LTD
发明人： NAKAZAWA ISAO
IPC分类号： H03C3/04 , H03C3/22

74. 发明专利

JPS60117979A PICTURE SIGNAL TRANSMISSION SYSTEM 失效
公开(公告)号：JPS60117979A
公开(公告)日：1985-06-25
申请号：JP22608883
申请日：1983-11-30
申请人： FUJITSU LTD
发明人： NAKAZAWA ISAO
IPC分类号： H04K1/00 , H04N7/167 , H04N7/169
摘要： PURPOSE:To avoid easy detection of picture signals and to keep satisfactorily the privacy with a system where the variation amount of a certain time difference from the picture signal, by controlling optionally said time difference. CONSTITUTION:A horizontal/vertical synchronizing signal detecting part 1 detects both horizontal and vertical synchronizing signals for some of the picture signals applied to an input terminal 5. A delay time control circuit 2 detects the order of the input horizontal synchronizing signal based on the vertical synchronizing signal. While the delay amount of a variable delay circuit 3 is previously decided in response to each horizontal synchronizing signal, and the circuit 3 is controlled to obtain the prescribed delay time. The rest picture signals supplied to the terminal 5 receive the delay from the circuit 3 and are supplied to another terminal of a differential amplification part 4 to be scrambled and delivered through a terminal 6 after the difference calculated from the picture signals supplied directly. At the reception side some of the reception signals supplied to a terminal 13 undergoes detection for both horizontal and vertical synchronizing signals through a horizontal/vertical synchronizing signal detecting part 7. Then the control exactly equal to the transmission side is given to a variable delay circuit 10 by means of said detected horizontal and vertical synchronizing signals.

75. 发明专利

JPS6043917A CLOCK PHASE ADJUSTING CIRCUIT 失效
公开(公告)号：JPS6043917A
公开(公告)日：1985-03-08
申请号：JP15266283
申请日：1983-08-22
申请人： FUJITSU LTD
发明人： KIYONO HIDEKI , NAKAZAWA ISAO
IPC分类号： H03K5/13 , H04L7/027
摘要： PURPOSE:To adjust continuously the phase of a clock by integrating the waveform the same as that of the clock and the inverted waveform and comparing the integrated output and a reference signal. CONSTITUTION:A clock input signal (1) is fed to an integration circuit 2 via a buffer 1-1 and an inverter 1-2. Comparators CP1, CP2 compare output signals (2), (3) from the integration circuit 2 with a reference voltage (a). An output from the comparator CP1 is inputted to a preset terminal PR of an FF5 and an output from the comparator CP2 is inputted to a clear terminal CLR. Further, phases 6, 7 of the clock are shifted optionally by adjusting the value of the reference voltage (a).

76. 发明专利

JPS605655A HIGH FREQUENCY KEYING CIRCUIT 失效
公开(公告)号：JPS605655A
公开(公告)日：1985-01-12
申请号：JP11333983
申请日：1983-06-23
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： NAKAZAWA ISAO , SAITOU TOSHIYUKI , KURITA OSAMU , OGAWA HIROTSUGU
IPC分类号： H04L27/06 , H04L27/20
摘要： PURPOSE:To facilitate spectrum controlling of carrier frequency band by detecting difference between actually obtained waveform spectrum and reference waveform in output of a keying element and synthesizing with reference waveform. CONSTITUTION:When a driving signal is impressed to the driving signal terminal DV of a non-linear keying element, a waveform shaping circuit WS is so adjusted that reference waveform that can drive the element to make the spread of waveform spectrum obtained in the output terminal OUT narrowest can be obtained. A differential amplifier DFA detects the difference between actually obtainable waveform spectrum and reference waveform in output of the keying element SW, and synthesize it with reference waveform by a synthesizing circuit H. By this way, feedback control is made to obtain ideal waveform from an output terminal OUT and to make output of the differential amplifier DFA small.

77. 发明专利

JPS604388A PICTURE SIGNAL TRANSMITTING DEVICE 失效
公开(公告)号：JPS604388A
公开(公告)日：1985-01-10
申请号：JP11324483
申请日：1983-06-23
申请人： FUJITSU LTD
发明人： NAKAZAWA ISAO , TSUKAGOSHI KENJIYU
IPC分类号： H04N7/08 , H04N7/081
摘要： PURPOSE:To transmit two analog picture signals through conventional one radio channel by transmitting a carrier after frequency-modulating the carrier with the 1st analog picture signal and further amplitue-modulating it with the 2nd analog picture signal. CONSTITUTION:The 1st analog picture signal supplied to a terminal 1 frequency- modulates a carrier by a frequency modulator FM. The output of the frequency modulator FM is further amplitude-modulated for about 50% with the 2nd analog picture signal supplied from another terminal 2 at an amplitude modulator AM. Then this modulated wave is mixed with the output wave of a transmitting local oscillator T-LOC at a frequency converter CON and radiated outside through an antenna ANT-1. At the receiving side, the mixed waves become the frequency-modulated component only by means of an amplitude limiter LIM and the 1st analog picture signal is regenerated by a frequency discriminator DISC which demodulates the frequency modulated component and, at the same time, only the 2nd analog signal is detected and outputted by means of an amplitude detector DET.

78. 发明专利

JPS596651A Modulator circuit 失效
标题翻译：调制器电路
公开(公告)号：JPS596651A
公开(公告)日：1984-01-13
申请号：JP11481682
申请日：1982-07-02
申请人： Fujitsu Ltd
发明人： YAGI TAKESHI , NAKAZAWA ISAO
IPC分类号： H04L27/12
CPC分类号： H04L27/12
摘要： PURPOSE:To simplify the constitution of the titled circuit and to shorten adjusting time, by using an LPf in common for both the prevension of leakage of carrier wave power and the limitation of the band width of a transmission signal. CONSTITUTION:A signal from a modulating signal source (e) is limited at its band width of a transmission signal by a filter circuit Z3 and applied to a variable capacity diode D1 together with a superposed DC bias. The oscillation frequency of a resonance circuit including the diode D1 is shifted in accordance with the band-imited transmission signal and outputted as an FSK modulated wave. In this case, carrier frequency which is almost equal to the resonance frequency is sufficiently higher thanthe frequency of the transmission signal. Thus, oscillating power is interrupted by the filter circuit Z3 and prevented from being leaked to the signal source (e) side.
摘要翻译：目的：为了简化标题电路的结构并缩短调整时间，通过对载波泄漏的上升和传输信号的带宽的限制，通常使用LPf。构成：来自调制信号源（e）的信号通过滤波器电路Z3限制在发送信号的带宽，并与叠加的DC偏压一起施加到可变电容二极管D1。包括二极管D1的谐振电路的振荡频率根据频带传输信号而偏移并作为FSK调制波输出。在这种情况下，几乎等于谐振频率的载波频率足够高于发送信号的频率。因此，振荡功率被滤波器电路Z3中断，并防止信号源（e）侧泄漏。

79. 发明专利

JPS58170240A DIGITAL RADIO COMMUNICATION SYSTEM 失效
公开(公告)号：JPS58170240A
公开(公告)日：1983-10-06
申请号：JP5252582
申请日：1982-03-31
申请人： FUJITSU LTD
发明人： NAKAZAWA ISAO
IPC分类号： H04J3/12 , H04B17/00 , H04J3/14 , H04L7/08
摘要： PURPOSE:To attain communication and control simply, by designating a non- modulation area between frame signals obtained from the speed conversion of digital signals of frame constitution as an area for service signal transmission. CONSTITUTION:A speed conversion circuit SPC speeds up a PCM signal so as to decrease the time for one frame and a modulation circuit MD1 modulates a carrier wave. Service signals SVS1, SVS2 are synthesized at a multiplex circuit MDX via the conversion circuit SPC, and the output of the MD1 is modulated at a modulation circuit MD2. In controlling a changeover switch SW with the timing pulse for synchronizing signal from an oscillation circuit SP, a signal of non- carrier is obtained and transmitted from an antenna AT via a transmitter TR. The service signal SVS is inserted to a vacant part TSP between adjacent frames produced with the conversion of bit rate.

80. 发明专利

JPS5687966A CARRIER WAVE PICKUP CIRCUIT 失效
公开(公告)号：JPS5687966A
公开(公告)日：1981-07-17
申请号：JP16467079
申请日：1979-12-20
申请人： FUJITSU LTD
发明人： NAKAZAWA ISAO
IPC分类号： H04J3/00 , H04L27/22 , H04L27/227
摘要： PURPOSE:To reduce an occurrence of phase jitter at switching of a filter for pickup of a carrier, by switching continuously two band filters with fixed band width. CONSTITUTION:Carrier burst input is given to two band pass filters 14, 15 having the same characteristics through dividing it into two at the brancher 11. Band pass filters 14, 15 have a fixed band to continuously switch the burst input with a burst switching controller 13, allowing to alternately supply it to the band pass filters 14 and 15. The carrier burst through the band pass filters 14 and 15 is fed to a synthesizer 16 and output as a continuous signal. Thus, the phase jitter at switching is made small and mechanical filters can be used.

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式