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公开(公告)号：US5077546A
公开(公告)日：1991-12-31
申请号：US610108
申请日：1990-11-07
IPC分类号： H03B19/18
CPC分类号： H03B19/18
摘要： A low phase noise frequency multiplier is disclosed for multiplying a sine wave obtained from a low phase noise crystal oscillator to higher frequencies than can be directly obtained from a crystal oscillator. The multiplication occurs without the ordinary increase in phase noise. The multiplier, when tripling the frequency contains a low phase noise frequency doubler. The double and triple frequency terms in the tripler are synthesized from two orthogonally related derivatives of the same wave, which are then multiplied in a double balanced mixer. The process reinforces the desired harmonics while not reinforcing the short term random phase noise, and produces a substantial improvement in the single sideband phase noise ratio over conventional frequency multipliers.
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公开(公告)号：US4271533A
公开(公告)日：1981-06-02
申请号：US164198
申请日：1980-06-30
申请人： Wilfred L. Hand , Victor J. Jacek
发明人： Wilfred L. Hand , Victor J. Jacek
摘要： An interface circuit that couples the output of a differential AFC detector to a tuner and in so doing provides a single-ended control signal and a substantially constant reference signal. A bridging circuit combines the differential outputs to effect a substantially constant signal which is appropriately scaled by a referencing circuit so as to develop the reference voltage required. A dividing circuit coupled to one of the differential outputs develops an AFC control voltage having the range required to accommodate the tuner's AFC-responsive circuitry.
摘要翻译： 将差分AFC检测器的输出耦合到调谐器并且这样做的接口电路提供单端控制信号和基本恒定的参考信号。 桥接电路组合差分输出以实现基本恒定的信号，其被参考电路适当地缩放以便产生所需的参考电压。 耦合到差分输出之一的分频电路产生具有适应调谐器的AFC响应电路所需范围的AFC控制电压。
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公开(公告)号：US5091699A
公开(公告)日：1992-02-25
申请号：US612485
申请日：1990-11-14
申请人： Bert K. Erickson , Robert R. Greenwood , Wilbert C. Kennedy , David W. Michel , David C. Allen , Victor J. Jacek
发明人： Bert K. Erickson , Robert R. Greenwood , Wilbert C. Kennedy , David W. Michel , David C. Allen , Victor J. Jacek
IPC分类号： H03B19/00
CPC分类号： H03B19/00
摘要： A frequency division network is disclosed in which a sinusoidal signal is converted to a digital format for frequency division and then converted back to the sinusoidal format, the sinusoidal output waveform having low phase noise. In a preferred embodiment the frequency conversion takes place in an m-fold plurality of edge triggered flip-flops, connected to divide by two, and clocked by the sinusoidal waveform. Each flip-flop is subject to jitter causing phase noise, which is minimized when the output of two sets of four flip-flops are averaged, and then filtered to obtain the sinusoidal fundamental. When a crystal filter having a very narrow pass band is employed, the phase noise is further reduced. The frequency division network uses low cost components and the phase noise of the output waveform approaches that of a stable crystal oscillator.
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公开(公告)号：US5255318A
公开(公告)日：1993-10-19
申请号：US839139
申请日：1992-02-20
申请人： Aravanan Gurusami , Robert Chamberlin , Victor J. Jacek , Thomas P. Strong , Jeffrey L. Cox , Mark Chapman
发明人： Aravanan Gurusami , Robert Chamberlin , Victor J. Jacek , Thomas P. Strong , Jeffrey L. Cox , Mark Chapman
CPC分类号： H04K3/825 , H04K3/41 , H04K3/42 , H04N7/166 , H04K2203/14 , H04K2203/34
摘要： A subscriber control system designed to be placed outside of the subscriber's home, for controlling access to cable television signals provided by a cable television headend. The system is modular in design containing a single control module and a single RF distribution module both shared by a number of jammer modules. The jammer modules contain a plurality of frequency agile oscillators, the frequencies of which can be changed in time-multiplex fashion. The outputs of the jammer modules can be shared amongst a number of subscribers using space division switching. The system features switching utilizing a plurality of series connected diodes to form a transmission line switch and also utilizes filters having inductive elements which are configured by etching processes
摘要翻译： 用户控制系统被设计为放置在用户家庭之外，用于控制对由有线电视头端提供的有线电视信号的访问。 该系统是模块化设计，包含单个控制模块和单个RF分配模块，由多个干扰模块共享。 干扰模块包含多个频率敏捷振荡器，其频率可以以时间复用的方式改变。 干扰模块的输出可以在使用空分切换的多个用户之间共享。 该系统具有利用多个串联连接的二极管的切换以形成传输线开关，并且还利用具有通过蚀刻工艺配置的电感元件的滤波器
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公开(公告)号：US5081433A
公开(公告)日：1992-01-14
申请号：US620667
申请日：1990-12-03
CPC分类号： G01S13/288 , H03C3/00 , H03C3/04
摘要： The invention relates to a two state phase modulator with minimum amplitude modulation. The modulator assumes two phase states differing by .THETA. where .THETA. is a sub-multiple of 180.degree. which permits a phase variation of 180.degree. for phase coded transmissions when the frequency of the phase modulated carrier wave is multiplied by the reciprocal of the sub-multiple. Three equal components are derived in the phase modulator: an in-phase, an out of phase, and a quadrature phase component. The out of phase component is delayed in relation to the in-phase component by .THETA./2, while the quadrature phase component is delayed .THETA./4. The in-phase and out of phase components are then reduced by a factor (2 sin .THETA./2) selected such that when added to the quadrature component, the resultants have a magnitude equal to that of the quadrature component and differ in phase from the quadrature comonent by .+-..THETA./2. The modulator output is formed of the resultants supplied in alternation with the quadrature component at zero phase being supplied during the transitions. Amplitude variation during the phase modulation process is reduced to a fraction of a decibel.
摘要翻译： 本发明涉及具有最小幅度调制的两状态相位调制器。 调制器假设两个相位状态不同于THETA，其中THETA是180°的子倍数，当相位调制载波的频率乘以子倍数的倒数时，允许相位变换为180°的相位编码传输的相位变化 。 在相位调制器中导出三个相等的分量：同相，异相和正交相位分量。 相位分量相对于同步分量由THETA / 2延迟，而正交相位分量延迟THETA / 4。 然后，同相和异相分量被选择为因子（2sin THETA / 2）减小，使得当加到正交分量时，结果的幅度等于正交分量的幅度，并且相位与 +/- THETA / 2的正交分子。 调制器输出由在转换期间提供的零相位正交分量交替提供的结果形成。 在相位调制过程中的幅度变化减小到分贝的分数。
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