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公开(公告)号：US5170495A
公开(公告)日：1992-12-08
申请号：US607385
申请日：1990-10-31
申请人： John D. McNicol , Stephen G. Harman
发明人： John D. McNicol , Stephen G. Harman
CPC分类号： H03G3/3042 , H04B2001/0425
摘要： In a QAM microwave radio communications system an IF (intermediate frequency) input signal is amplified and predistorted, and the amplified IF signal is mixed with a local oscillator signal to produce an RF (radio frequency) signal which is amplified in a power amplifier for transmission, the predistortion compensating for non-linear gain of the power amplifier. Clipping in the power amplifier is controlled by down-converting part of the RF signal to produce an IF output signal, monitoring amplitude distortion of the RF signal by comparing the IF output signal with the IF input signal, and controlling the IF amplifier gain in dependence upon the monitored amplitude distortion.
摘要翻译： 在QAM微波无线电通信系统中，IF（中频）输入信号被放大和预失真，并且放大的IF信号与本地振荡器信号混合以产生RF（射频）信号，该RF（射频）信号在用于传输的功率放大器中被放大 ，预失真补偿功率放大器的非线性增益。 功率放大器中的钳位通过下变频部分RF信号来控制，以产生IF输出信号，通过将IF输出信号与IF输入信号进行比较来监测RF信号的幅度失真，并依赖于IF放大器增益 受监控的幅度失真。
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公开(公告)号：US4088967A
公开(公告)日：1978-05-09
申请号：US789242
申请日：1977-04-20
申请人： Stephen G. Harman
发明人： Stephen G. Harman
CPC分类号： H04L27/2035 , H03C1/58
摘要： A transformer coupled split-ring diode modulator for digital phase modulation of a data stream in which the diodes are back-biased so as to provide additional attenuation of in-band fold-over side lobes which appear in the pass-band; the additional attenuation resulting from a cosine attenuation function which is dependent upon the switching time of the diodes and hence the bias voltage applied thereto.
摘要翻译： 一种用于数据流的数字相位调制的变压器耦合分裂二极管调制器，其中二极管被反向偏置，以便提供出现在通带中的带内折叠旁瓣的附加衰减; 由余弦衰减函数产生的附加衰减，其取决于二极管的开关时间，并因此取决于施加到其上的偏置电压。
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公开(公告)号：US5033110A
公开(公告)日：1991-07-16
申请号：US524904
申请日：1990-05-18
申请人： Stephen G. Harman
发明人： Stephen G. Harman
CPC分类号： H03D7/168 , H03D2200/0047 , H03D7/18
摘要： A frequency converter for a transmitter of a microwave radio communications system comprises an image reject mixer for mixing an IF signal with an LO or carrier frequency signal to produce an RF signal, and a nulling circuit for providing d.c. offsets to the image reject mixer to reduce carrier leak to the RF signal. The nulling circuit includes a source of phase quadrature chopper signals which are cross modulated with the LO signal to produce a modulated signal, and a single-ended mixer for mixing the modulated signal with part of the RF signal. The output of the single-ended mixer is low pass filtered and the resulting filtered signal is cross demodulated with the chopper signals to produce phase quadrature correction signals, which are integrated to produce the d.c. offsets for the image reject mixer. The arrangement avoids the need for, and expense of, a subsequent carrier frequency filter.
摘要翻译： 一种用于微波无线电通信系统的发射机的变频器包括用于将IF信号与LO或载波频率信号混合以产生RF信号的图像拒绝混合器，以及用于提供直流电平的零电路。 抵消图像抑制混频器以减少载波泄漏到RF信号。 归零电路包括用LO信号进行交叉调制以产生调制信号的相位正交斩波信号源，以及用于将调制信号与RF信号的一部分混合的单端混频器。 单端混频器的输出被低通滤波，所得到的滤波信号用斩波信号进行交叉解调，以产生相位正交校正信号，其被积分以产生直流电平。 图像拒绝混音器的偏移量。 该装置避免了后续载波频率滤波器的需要和费用。
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公开(公告)号：US4460875A
公开(公告)日：1984-07-17
申请号：US390521
申请日：1982-06-21
申请人： Stephen G. Harman
发明人： Stephen G. Harman
CPC分类号： H03F3/60 , H03F1/345 , H03F2200/198
摘要： An intermediate frequency preamplifier of a microwave radio receiver includes an amplifier circuit having a negative feedback path including a directional coupler constituted by two transformers. One port of the directional coupler is terminated with a complex impedance, producing a controlled mis-match, which is adjustable to optimize the input return loss of the amplifier without changing the noise figure of the preamplifier. The amplifier circuit has a low impedance output constituted by a common-collector transistor so that the signal reflected back into the directional coupler by the mis-match does not significantly affect the output of the amplifier.
摘要翻译： 微波无线电接收机的中频前置放大器包括具有包括由两个变压器构成的定向耦合器的负反馈路径的放大器电路。 定向耦合器的一个端口以复阻抗端接，产生可控的误匹配，其可调节以优化放大器的输入回波损耗而不改变前置放大器的噪声系数。 放大器电路具有由公共集电极晶体管构成的低阻抗输出，使得通过不匹配反射回定向耦合器的信号不会显着影响放大器的输出。
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公开(公告)号：US06990267B2
公开(公告)日：2006-01-24
申请号：US10633389
申请日：2003-08-04
CPC分类号： G02B6/3572 , G02B6/3508 , G02B6/355 , G02B6/3582
摘要： A moving fiber optical switch of the type having two opposed supports carrying optical fibers with a gap between the fiber ends, with at least one of the supports being flexibly mounted for pivotal movement relative to the other support, and in which:(1) an actuator means, which provides pivotal movement of one or both supports between two orientations corresponding to first and second relative positions of the fiber supports, is connected to a connecting member or housing by means of a flexure;(2) the switch has means for adjusting the length of the gap between the fiber ends; and(3) the switch has means for adjusting the alignment of the optical fiber ends in a direction perpendicular to the movement provided by the pivotal movement of the flexibly mounted support or supports.
摘要翻译： 一种移动光纤光开关，其具有两个相对的载体，其携带在光纤端部之间具有间隙的光纤，其中至少一个支撑件被灵活地安装成相对于另一支撑件枢转运动，其中：（1） 致动器装置，其在对应于纤维支撑件的第一和第二相对位置的两个取向之间提供一个或两个支撑件的枢转运动，通过挠曲件连接到连接构件或壳体; （2）开关具有用于调整光纤端之间的间隙的长度的装置; 和（3）开关具有用于调节光纤端部在与由柔性安装的支撑件或支撑件的枢转运动所提供的运动垂直的方向上的对准的装置。
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公开(公告)号：US06606444B2
公开(公告)日：2003-08-12
申请号：US10179945
申请日：2002-06-26
IPC分类号： G02B638
CPC分类号： G02B6/4226
摘要： A positioning device suitable for accurately positioning objects such as optical fibers includes a first support, a movable support restrained for movement relative to the first support with one degree of freedom and carrying a holder for the object to be positioned, and an intermediate support which is connected to the first support by a pair of first spaced flexible elements of equal length and which is connected to the movable support by a pair of second spaced flexible elements, the second pair also being equal in length to each other. The first and second flexible elements are oppositely arranged and dimensioned so that arc-errors in the movement of the intermediate support caused by bending of the first flexible elements are substantially compensated by arc movements of the second flexible elements to produce a desired movement of the movable support, which may be rectilinear or angular movement about an axis. An actuator causes movement of the movable support with bending of all the flexible elements, and a control member connects the first support, the intermediate support and the movable support so that the degree of movement of the intermediate support is one half the movement of the movable support.
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公开(公告)号：US5559423A
公开(公告)日：1996-09-24
申请号：US220651
申请日：1994-03-31
申请人： Stephen G. Harman
发明人： Stephen G. Harman
CPC分类号： G05F1/565
摘要： A voltage regulator for an electronic circuit card includes a FET with a source supplied via an input LC filter with a voltage to be regulated, a drain for delivering a regulated output voltage via a current-sensing resistor and an output LC circuit, and a gate which is supplied with a current drive from a linear transconductance amplifier having a differential input responsive to the regulated output voltage relative to a reference voltage. The regulator provides large bandwidth low voltage drop regulation without requiring higher voltage supply for the gate of the FET. A current limiting circuit reduces the current drive in response to excessive current through the current-sensing resistor, and a turn-on control circuit reduces the current drive to provide a controlled turn-on for hot insertion of the card into electronic equipment.
摘要翻译： 用于电子电路卡的电压调节器包括具有通过具有待调节电压的输入LC滤波器提供的源极的FET，用于通过电流检测电阻器和输出LC电路输出稳定的输出电压的漏极和输入端 其被提供有来自线性跨导放大器的电流驱动器，其具有响应于相对于参考电压的调节的输出电压的差分输入。 调节器提供大带宽低压降调节，而不需要FET的栅极的较高电压供应。 电流限制电路响应于通过电流感测电阻器的过大电流来减小电流驱动，并且导通控制电路减小了电流驱动以提供可控开启以将卡热插入电子设备。
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公开(公告)号：US5193224A
公开(公告)日：1993-03-09
申请号：US690432
申请日：1991-04-24
申请人： John D. McNicol , Stephen G. Harman
发明人： John D. McNicol , Stephen G. Harman
CPC分类号： H03F1/3247 , H03C3/08 , H03F1/3258 , H03F1/3282 , H04L27/368 , H03F2200/438 , H03F2201/3233
摘要： In a QAM microwave radio communications system an IF (intermediate frequency) input signal is amplified and predistorted, and the amplified IF signal is mixed with a local oscillator signal to produce an RF (radio frequency) signal which is amplified in a power amplifier for transmission, the predistortion compensating for non-linearity of the power amplifier. Adaptive phase control of the predistorter is provided by mixing the local oscillator signal with part of the RF signal to produce an IF output signal representative of the output of the power amplifier, detecting phase differences between the IF input and IF output signals to produce a phase difference signal, selectively inverting the phase difference signal in dependence upon whether or not an IF signal amplitude exceeds a comparison level, and integrating the selectively inverted phase difference signal to produce a phase control signal for the predistorter.
摘要翻译： 在QAM微波无线电通信系统中，IF（中频）输入信号被放大和预失真，并且放大的IF信号与本地振荡器信号混合以产生RF（射频）信号，该RF（射频）信号在用于传输的功率放大器中被放大 ，补偿功率放大器非线性的预失真。 通过将本地振荡器信号与RF信号的一部分混合来产生预失真器的自适应相位控制，以产生表示功率放大器的输出的IF输出信号，检测IF输入和IF输出信号之间的相位差，以产生相位 差分信号，根据IF信号幅度是否超过比较电平，选择性地反相相位差信号，并积分有选择地反相的相位差信号，以产生用于预失真器的相位控制信号。
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公开(公告)号：US4513250A
公开(公告)日：1985-04-23
申请号：US499309
申请日：1983-05-31
申请人： Stephen G. Harman
发明人： Stephen G. Harman
CPC分类号： H03F1/3241
摘要： A signal cuber for producing the third harmonic of an input signal, for use in a signal distortion correction circuit, comprises a split-ring mixer having two ports, at which there is produced a signal at the second harmonic of the input signal, unequally terminated, whereby the second harmonic signal is reflected into the mixer to be mixed with the input signal to produce the third harmonic. The mixer can consist of transformers and diodes, which can be Schottky diodes which are forward biassed by a potential difference supplied to the ports via the unequal terminations, which may be constituted by a single resistor.
摘要翻译： 用于产生用于信号失真校正电路的输入信号的三次谐波的信号调理器包括具有两个端口的分离式环形混频器，在该端口处产生输入信号的二次谐波的信号，不同端接 由此二次谐波信号被反射到混合器中以与输入信号混合以产生三次谐波。 混频器可以由变压器和二极管组成，其可以是肖特基二极管，其由通过不同端子提供给端口的电势差向前偏置，这可以由单个电阻器构成。
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