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公开(公告)号：US5150080A
公开(公告)日：1992-09-22
申请号：US806956
申请日：1991-12-12
CPC分类号： H03L7/02 , H03B5/1864 , H03B2200/0024 , H03B2200/0048 , H03B2200/0056 , H03B2200/0072 , H03B2200/0088 , H03B2200/009 , H03B2201/0258 , H03B2202/025 , H03B2202/076 , H03B5/1841
摘要： An oscillator includes an amplifier having an input and an output and a feedback circuit disposed between the input and the output of the amplifier. The feedback circuit includes a plurality of resonators and a pair of switches. Each switch includes a first port and multiple connectable ports, the multiple connectable ports of each switch connected to a corresponding one of the plurality of resonators. The feedback circuit further includes a voltage-controlled phase shifter disposed in series with the switches. The oscillator further includes a discriminator circuit, responsive to signals from the feedback circuit, for providing a control signal to the voltage-controlled phase shifter for degenerating low frequency noise within the oscillator. With such an arrangement, high Q low noise resonators can be switched in and out of the circuit thus providing improved phase noise performance at high power levels with the desirable frequency agility required for a microwave oscillator.
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公开(公告)号：US5032800A
公开(公告)日：1991-07-16
申请号：US538439
申请日：1990-06-15
CPC分类号： H03B9/142 , H03B5/1882 , H03B2009/126 , H03B2200/0088 , H03B2200/009 , H03B2201/0241 , H03B2201/033 , H03B2202/076 , H03B5/1841
摘要： An oscillator providing predictable oscillator modulation sensitivity includes an amplifier and a feedback circuit disposed about the amplifier. The feedback circuit includes a resonator having a first port and a second port and a voltage-controlled phase shifter having an input port, an output port and a control port, the input port of the voltage-controlled phase shifter connected to the output port of the amplifier and the output port of the voltage-controlled phase shifter coupled to a port of the resonator. The oscillator further includes a circuit, responsive to signals from the output of the voltage-controlled phase shifter and the first port of the resonator, to provide a control signal to the control port of the voltage-controlled phase shifter for degenerating low frequency FM noise arising within the amplifier.
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公开(公告)号：US4912432A
公开(公告)日：1990-03-27
申请号：US339534
申请日：1989-04-17
CPC分类号： H03L7/23
摘要： A multiple feedback loop frequency synthesizer, having a first and a second feedback loop, each fed by one of a pair of reference frequency signals having a frequency separation equal to the desired frequency separation of the output signals provided by the synthesizer. The frequency of each of such reference frequency signals is greater than the desired frequency separation of the output signals provided by the synthesizer. With such arrangement, because the bandwidth of each of the feedback loops must be less than the frequency of the reference frequency signal fed to such loop, achievement of frequency separation less than the frequency of either one of the reference frequencies enables each of the feedback loops to have increased bandwidth and hence reduced frequency switching times and increased noise suppression.
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公开(公告)号：US4758800A
公开(公告)日：1988-07-19
申请号：US33306
申请日：1987-04-02
申请人： Robert DiBiase , Zvi Galani , Raymond C. Waterman, Jr. , Ernst F. R. A. Schloemann , Ronald E. Blight
发明人： Robert DiBiase , Zvi Galani , Raymond C. Waterman, Jr. , Ernst F. R. A. Schloemann , Ronald E. Blight
CPC分类号： H01P1/218
摘要： A magnetically tuned resonant circuit having improved noise performance includes a ferrimagnetic or gyromagnetic body such as a YIG sphere which is disposed within r.f. structure, The r.f. structure is disposed between a pair of pole pieces of a biasing magnet and flux return path. Several techniques are described for reducing fluctuations in magnetic fields through the gyromagnetic body. The gyromagnetic body is isolated from conductive surfaces, or the bulk of conductive surfaces in the region adjacent to the magnetic body are reduced. Further, a technique is also described which provides a break in the electrical continuity around the r.f. structure. Each of these technique reduce the magnitude of thermally induced eddy current flow in conductive regions adjacent to the resonant body. It is believed that such eddy current flow produce random magnetic field variations which produce random variations in the frequency characteristics of conventional magnetically tuned resonant circuits.
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公开(公告)号：US4555678A
公开(公告)日：1985-11-26
申请号：US554012
申请日：1983-11-21
CPC分类号： H03B5/1894 , H03B2200/0088 , H03B2202/076
摘要： An improvement in a microwave oscillator using a GaAs FET as the active element is shown to include a phase detector responsive to a portion of the positive feedback signals applied to a resonator having a high Q and to a portion of the signals out of the GaAs FET, shifted by 90.degree., to obtain signals to degenerate noise internally formed in the GaAs FET.
摘要翻译： 使用GaAs FET作为有源元件的微波振荡器的改进被示为包括相位检测器，该相位检测器响应于施加到具有高Q的谐振器的一部分的正反馈信号和来自GaAs FET的信号的一部分 ，偏移90°，以获得GaAs FET内部形成的退化噪声信号。
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公开(公告)号：US5019792A
公开(公告)日：1991-05-28
申请号：US425144
申请日：1989-10-23
摘要： A tunable bandpass filter for radio frequency energy with a phase-locked loop for tracking an input signal and to control the filter to keep the center frequency of the passband coincident with the frequency of the input signal is shown. Using a Yttrium Iron Garnet (YIG) filter as a frequency determining element and as a passive dispersive reference element for a frequency discriminator, the bandpass filter uses the output signal of the discriminator to form a fine tuning signal to control the center frequency of the passband of the YIG filter.
摘要翻译： 示出了用于射频能量的可调谐带通滤波器，其具有用于跟踪输入信号的锁相环并且控制滤波器以保持通带的中心频率与输入信号的频率一致。 使用钇铁石榴石（YIG）滤波器作为频率确定元件，并作为用于鉴频器的无源色散参考元件，带通滤波器使用鉴频器的输出信号形成微调信号，以控制通带的中心频率 的YIG滤波器。
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7.发明授权
公开(公告)号：US4510463A
公开(公告)日：1985-04-09
申请号：US487778
申请日：1983-04-22
CPC分类号： H03D3/22 , H03L7/02 , H03D2200/0031 , H03D2200/0082
摘要： A frequency discriminator having a wide capture band is shown to comprise, in addition to a conventional phase detector having two channels fed by a signal whose frequency is to be determined (the first one of the channels containing a tuned circuit operative to shift the phase of the signal in accordance with the difference between the frequency of the signal and the center frequency of the tuned circuit and the second one of the channels containing a phase shifter operative to shift the phase of the signal by 90.degree. regardless of the frequency of the signal), a compensating circuit operative substantially to equalize the amplitudes of the signals applied to the phase detector, the compensating circuit including an amplifier in the first one of the channels to amplify the signal out of the tuned circuit, the gain of the amplifier being controlled by a signal indicative of the difference between the amplitudes of the signals fed to the phase detector.
摘要翻译： 具有宽捕获带的鉴频器除了具有由要被确定频率的信号馈送的两个信道的常规相位检测器之外还包括（第一个信道包含调谐电路，该调谐电路可操作以使 根据信号的频率和调谐电路的中心频率之间的差异以及包含移相器的通道的第二个信号的信号可操作以将信号的相位偏移90°，而不管信号的频率如何 ），补偿电路基本上用于均衡施加到相位检测器的信号的幅度，补偿电路包括在第一通道中的放大器以放大调谐电路中的信号，放大器的增益被控制 通过表示馈送到相位检测器的信号的幅度之间的差异的信号。
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8.发明授权Ferrite phase shifter having conductive material plated around ferrite assembly 失效具有导电材料的铁素体相变材料在铁素体组件周围
公开(公告)号：US4001733A
公开(公告)日：1977-01-04
申请号：US605789
申请日：1975-08-18
CPC分类号： H01P1/195
摘要： A radio frequency phase shifter suitable for X-band operation is disclosed. Such phase shifter incudes a waveguide structure and a ferrite assembly disposed within such waveguide structure. The ferrite assembly has a conductive material plated on the sides thereof. A pair of such plated sides is in contact with the wide walls of the waveguide structure thereby preventing the generation of longitudinal section modes (i.e. LSE.sub.1,1, LSM.sub.1,1, and LSE.sub.1,2) and another pair of such plated walls is displaced from the narrow walls of such waveguide structure to form a pair of waveguide sections cut off to the dominant mode of the radio frequency energy passing through the ferrite phase shifter thereby inhibiting such energy from coupling to wires passing through such waveguide sections for supplying drive current to the enclosed ferrite assembly. Because the waveguide structure may be flexed and has a width greater than the width of the ferrite assembly, the ferrite assembly may be inserted within the waveguide structure, when flexed, to provide the desired contact between the plated sides of the ferrite assembly and the wide walls of the waveguide structure when the latter returns to its original dimensions.
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