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公开(公告)号：JPH01248715A
公开(公告)日：1989-10-04
申请号：JP7575588
申请日：1988-03-29
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
IPC: G01S5/02 , G01S19/14 , H04B1/3822 , H04B1/40
Abstract: PURPOSE:To allow the title equipment to be connected to any mobile body communication network/ranging network of a ground system/satellite system by allowing an individual antenna and a high frequency section to cope with the ground system and the satellite system respectively and using the circuits after those handling the IF band in common. CONSTITUTION:The high frequency section 2(2') applies mainly frequency conversion between a radio frequency signal of the satellite system (ground system) sent/received by an antenna 1(1') and a signal of the prescribed intermediate frequency(IF) band in a reception/transmission IF system 4(5). A respectively IF switch circuit 3-1 receives a reception switching control signal outputted from a base band processing section 6a and supplies any output IF signal of the said high frequency sections 2, 2' to the reception IF system 4. Moreover, a transmission IF switch circuit 3-2 receives a transmission switching control signal outputted from the base band processing section 6a and supplies the transmission IF signal being an output of the transmission IF system 5 to either of the said high frequency section 2(2'). Thus, the circuits after those using the IF band are used in common and the single device is connected to any communication network/ranging network of the ground system/satellite system.
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公开(公告)号：JPS646884A
公开(公告)日：1989-01-11
申请号：JP16096087
申请日：1987-06-30
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
Abstract: PURPOSE:To easily generate a variable chirp signal by setting a chirp rate and signal time length independently by setting the constant of a constant generator and the initial value of a digital integrator with output pulses of a counter. CONSTITUTION:The constant generated by the constant generator 15 is integrated twice through digital integrators 20-1 and 20-2 to obtain a phase signal as a secondary time function. This phase signal is inputted to ROMs 5 and 6, whose outputs are passed through D/A converters 7 and 8 to obtain complex chirp signals of the base band consisting of COS chirp signals and SIN chirp signals. Those signals are passed through mixers 11 and 12 and a signal composing device 13 to obtain a chirp signal of the IF or RF band. The chirp rate is obtained according to a numeral set in the constant generator 15 and the optional time length is obtained from the frequency division ratio of a counter 2 where the initial values of memories 4 and 17 of the integrators 20-1 and 20-2 are set.
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公开(公告)号：JPS63151123A
公开(公告)日：1988-06-23
申请号：JP29678186
申请日：1986-12-15
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
Abstract: PURPOSE:To attain narrow band communication with high performance even in a transmission system of much phase noise by allowing a reception signal to pass tracking type band-pass filters and converting the frequency of a part of the output of a frequency synthesizer to an intermediate frequency IF frequency band as a local signal. CONSTITUTION:The reception signal is allowed to pass tracking type band pass filters 1 and 2 to select the signal of a channel to be received, and a reproduced pilot signal of the signal of the reception channel has the frequency converted to a low frequency band as the local signal. Further, a part of the output of a frequency synthesizer 5 has the frequency converted to the IF frequency band as the local signal to obtain a channel signal to be received in a certain frequency band independently of channels, and this signal is demodulated and reproduced. Thus, the phase noise generated in a transmission line part and a reception equipment is eliminated, and narrow band communication of stable and satisfactory characteristic is by attained the synchronous demodulation method.
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公开(公告)号：JPS62220014A
公开(公告)日：1987-09-28
申请号：JP6370686
申请日：1986-03-20
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
Abstract: PURPOSE:To apply filtering to many kinds of signals with no adjustment to output by providing a digital low pass filter array in n-stage cascade connection after an A/D converter sampled by a frequency being twice or over of the highest frequency of a demodulation signal. CONSTITUTION:A sample pulse generator 5 generates a sample pulse having a frequency being twice or over of the highest frequency of a demodulation signal and outputs it to an A/D converter 4. The A/D converter 4 samples a demodulation signal through an analog low pass filter by using a sample pulse and converts it into a digital signal. A digital low pass filter array 6 of n-stage in cascade connection is placed after the A/D converter 4 and signals having n-kind of data speeds included in the output of the A/D converter 4 are filtered and outputted sequentially in the order of lower data speed.
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公开(公告)号：JPS61234154A
公开(公告)日：1986-10-18
申请号：JP7513185
申请日：1985-04-09
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
Abstract: PURPOSE:To operate effectively a modulator and a demodulator by a required mode without an order line by transmitting a binary data of K bit by modulating a polarity of plural K number of fixed patterns in a transmitting side and identifying a modulating mode thereby in a receiving side. CONSTITUTION:By detecting a synchronous fixed pattern UW0 outputted from a fixed pattern detector 2 in accordance with a frame pulse 106 outputted from a receiving frame synchronous circuit 3, 'ambiguity removing signal' 108 is obtained. A fixed pattern polarity signal 110 removing 'ambiguity error' by an exclusive logical adder 10 is identified by an aperture pulse 109 and inputted to a mode deciding circuit 5. A fixed pattern detecting signal 104 similarly enters a change-over detection circuit 4 identified by the aperture pulse 109. The change-over detection circuit 4 decides that a change-over signal frame is received by the generation of fixed pattern detecting pulses of more than a fixed number. The mode deciding circuit 5 generates a mode control signal 114 and starts a control of a demodulator 1 by a new mode.
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Patent Agency Ranking
公开(公告)号：JPS61139128A
公开(公告)日：1986-06-26
申请号：JP26057184
申请日：1984-12-10
Applicant: Nec Corp
Inventor： ICHIYOSHI OSAMU
CPC classification number: H04B7/26
Abstract: PURPOSE:To increase the number of channels without increasing the number of base stations by arranging directional antennas, which are directed to individual subregions from positions near a specific point, in the base station and reducing the interference of signals from mobile stations in subregions by interference wave canceling circuits. CONSTITUTION:If the division number of subregions is defined as K, the base station is installed in the center of a region, and K-number of directional antennas are used to perform the communication with mobile stations in semiregions. Each channel is divided to a maximum of K-m-number of parts by a channel signal branching circuit 13, and one of them is supplied to the main signal input of an interference wave canceling circuit 14 for the channel of the pertinent semiregion, and the others are supplied to receiving circuits for the other subregions using the same frequency. The pertinent frequency channel signal from the other subregions using the same frequency is supplied to the interference wave canceling circuit 14 as an auxiliary signal. The interference wave canceling operation is performed automatically in each interference wave canceling circuit 14, and a signal of high SIR obtained as the result is supplied to a demodulating circuit 15, and the signal is reproduced in this circuit 15.
Abstract translation: 目的：通过在基站中布置定向天线，从基站附近的位置排列定向天线，增加信道数目，减少干扰下的子区域信号的干扰 波消除电路。 构成：如果将子区域的划分数定义为K，则将基站安装在区域的中心，并且使用K个定向天线来执行与半个移动站的通信。 每个通道被通道信号分支电路13分成最大的Km部件数，并且其中一个信号被提供给干涉波消除电路14的主信号输入用于相关半准则的信道，其他的 被提供给使用相同频率的其他子区域的接收电路。 来自使用相同频率的其他子区域的相关频道信号作为辅助信号提供给干扰波消除电路14。 在每个干扰波消除电路14中自动执行干扰波消除操作，并将作为结果获得的高SIR信号提供给解调电路15，并在该电路15中再现信号。
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公开(公告)号：JPS58182323A
公开(公告)日：1983-10-25
申请号：JP6462382
申请日：1982-04-20
Applicant: Nec Corp
Inventor： ICHIYOSHI OSAMU
IPC: H04B1/26 , H03L7/10 , H03L7/113 , H04L27/227
CPC classification number: H04L27/2272 , H03L7/10
Abstract: PURPOSE: To offer a PLL which attains sure and quick locking, by providing a phase shifter phase-shifting an output signal by (π/2)+nπ (where; n is an integer) for output for the pre-stage of a phase comparator.
CONSTITUTION: In Figure, 4 is a π/2 phase shifter, 5 is a multiplier, 6 is a low pass filter and 7 is a multiplier. When |ωe| is sufficiently larger against the frequency band of a loop filter 3, VCO1 is frequency-converted and the |ωe| is decreased. When the |ωe| enters the locking range of the PLL, the synchronism is attained rapidly and ωe=0 is attained. In case of the asynchronous state, the circuit is operated as an AFC circuit so as to decrease the frequency error and when the frequency error is within the range of synchronism, the PLL is operated as a phase synchronism circuit.
COPYRIGHT: (C)1983,JPO&JapioAbstract translation: 目的：通过提供一个移相器，通过（pi / 2）+ npi（其中; n是一个整数）将输出信号相位移相，用于输出相位的前级 比较器。 构成：在图中，4是π/ 2移相器，5是乘法器，6是低通滤波器，7是乘法器。 当|omegae |相对于环路滤波器3的频带足够大时，VCO1被频率转换，并且|omegae |被减小。 当|omegae进入PLL的锁定范围时，快速获得同步，并达到omega = 0。 在异步状态的情况下，电路作为AFC电路工作，以降低频率误差，当频率误差在同步范围内时，PLL作为相位同步电路运行。
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公开(公告)号：JPH09284242A
公开(公告)日：1997-10-31
申请号：JP9283496
申请日：1996-04-15
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
Abstract: PROBLEM TO BE SOLVED: To provide a communication equipment with a small scale whose band width is variable in the frequency division multiplex communication. SOLUTION: In a multiplexer at a transmitter side, an A/D converter 3 converts each channel signal into a digital signal, a complex multiplier 5 converts the signal into a complex signal with different frequency for each channel interval Δf and the signal is fed to an IFFT circuit 8 conducting inverse Fourier transformation via a switch circuit 6 having plural switch elements 7. Nyquist characteristic digital sub filters 10-1 to 10-N whose Nyquist frequency of Δf/2 are arranged to the output of the IFFT circuit 8 and outputs of the digital sub filters 10-1 to 10-N are added by an adder circuit 12 via delay devices 11-1 to 11-N. A demultiplexer at a receiver side is configured similarly to the multiplexer. The band width is changed by changing the state of each switch element 7.
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公开(公告)号：JPH09223997A
公开(公告)日：1997-08-26
申请号：JP33080096
申请日：1996-12-11
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
Abstract: PROBLEM TO BE SOLVED: To secure the synchronization among earth stations even in a multi- beam system that generally has no return path. SOLUTION: An earth station 2 generates the transmission timing of its own transmission burst based on a time piece device 221 and also detects the time when the signal is received from another station. The transmission timing of its on station and the information on the signal receiving time of another station are notified with each other among the stations 22 via the control burst. Then the time error of every station is calculated by solving the simultaneous equations where the time error of the device 221 of every station 2 and the propagation time required to a satellite 1 are defined as the unknown quantities. Based on this time error, the time of the device 221 is corrected. Thus the synchronization of time is secured among the stations 2.
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公开(公告)号：JPH0898235A
公开(公告)日：1996-04-12
申请号：JP22765294
申请日：1994-09-22
Applicant: NEC CORP
Inventor： ICHIYOSHI OSAMU
Abstract: PURPOSE: To provide the radio communication system where many and unspecified radio terminal stations or subscribers of a public network can share the same speech channel to execute even the intra-group speech in the radio communication network of the full duplex system. CONSTITUTION: In the radio communication system where a radio base station uses a common control line to assign idle speech channels to radio terminal stations which request speech, each of plural radio terminal stations generates a speaking right request signal from a generation circuit 412 to transmit it to the radio base station by radio at the time of turning-on of a speaking right request switch 37 when the absence of a reception signal is detected by a reception signal presence/absence detector 403. Each radio terminal station is provided with a display device 38 on which the speaking permission state is displayed, a speaking permission signal detector 402 which detects the speaking permission signal destined for the station itself, and a control means which displays the speaking permission state on the display device and makes a transmission part operatable at the time of detecting the speaking permission signal.
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