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公开(公告)号：US5918167A
公开(公告)日：1999-06-29
申请号：US815121
申请日：1997-03-11
CPC分类号： H03D3/008 , H04B1/30 , H03D2200/0027 , H03D2200/0047 , H03D2200/009
摘要： A quadrature downconversion stage in a radio frequency receiver compensates for leakage from the quadrature local oscillator to the input of the stage by deriving first and second feedback signals from the quadrature local oscillator. The first feedback signal is 180.degree. out of phase with the in-phase component of the signal supplied to the input of the stage and the second feedback signal is 180.degree. out of phase with the quadrature component of the signal supplied to the input of the stage. The invention reduces or cancels a d.c. offset that can appear at the output of the stage. Another advantage is the reduction of re-radiated signals resulting from the local oscillator leakage. The invention is particularly applicable to direct converters.
摘要翻译： 无线电频率接收机中的正交下变频级通过从正交本地振荡器得到第一和第二反馈信号来补偿从正交本地振荡器到级的输入的泄漏。 第一反馈信号与提供给级输入的信号的同相分量相差180°，第二反馈信号与提供给输入端的信号的信号的正交分量相差180° 阶段。 本发明减少或取消直径 偏移可以出现在舞台的输出端。 另一个优点是减少由本地振荡器泄漏引起的再辐射信号。 本发明特别适用于直接转换器。
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公开(公告)号：US6144254A
公开(公告)日：2000-11-07
申请号：US325902
申请日：1999-06-04
CPC分类号： H03G1/0023
摘要： A low noise radio frequency amplifier is switchable between a low gain state and a high gain state. A first, common-emitter transistor is active in the high gain state and inactive in the low gain state. The first transistor has a base coupled to a radio frequency input and a first bias input, an emitter coupled to ground, and a collector coupled to an amplified radio frequency output. A second, common-base transistor is active in the low gain state and inactive in the high gain state. The second transistor has an emitter coupled to the radio frequency input, a base coupled to a second bias input, and a collector coupled to the amplified radio frequency output.
摘要翻译： 低噪声射频放大器可在低增益状态和高增益状态之间切换。 第一个共发射极晶体管在高增益状态下有效，而在低增益状态下是无效的。 第一晶体管具有耦合到射频输入和第一偏置输入的基极，耦合到地的发射极和耦合到放大射频输出的集电极。 第二个公共晶体管在低增益状态下有效，在高增益状态下是无效的。 第二晶体管具有耦合到射频输入的发射极，耦合到第二偏置输入的基极和耦合到放大的射频输出的集电极。
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公开(公告)号：US6052026A
公开(公告)日：2000-04-18
申请号：US986784
申请日：1997-12-08
CPC分类号： H03G1/0023
摘要： A linear gain controlled amplifier comprising a differential transistor pair having an input and an output. The input is connected to a current supply which includes both AC and DC components. A voltage is derived which is proportional to the DC current component and this is compared with a control signal to produce an error signal which is supplied to the gain control terminals of the differential transistor pair. Traditionally, gain control has been implemented using a closed loop consisting of a power detector, a loop filter and a gain control element. The output of the power detector is compared with a reference voltage in a comparator, the output of which is filtered by the loop filter and applied to a control input of the gain control element. Most power detectors are either inaccurate or expensive and elaborate and may exhibit a control error of several decibels. The gain control elements themselves typically have non-linear control characteristics and suffer from poor repeatability and temperature variations which can necessitate extensive calibration. The present invention substantially avoids the foregoing problems by avoiding use of the prior art power detector and gain control element.
摘要翻译： 一种线性增益控制放大器，包括具有输入和输出的差分晶体管对。 输入连接到包括交流和直流分量的电流源。 导出与DC电流分量成比例的电压，并将其与控制信号进行比较，以产生提供给差分晶体管对的增益控制端的误差信号。 传统上，使用由功率检测器，环路滤波器和增益控制元件组成的闭环来实现增益控制。 功率检测器的输出与比较器中的参考电压进行比较，其输出由环路滤波器滤波并被施加到增益控制元件的控制输入端。 大多数功率检测器是不精确的或昂贵的和精细的，并且可能表现出几分贝的控制误差。 增益控制元件本身通常具有非线性控制特性，并且具有差的重复性和温度变化，这可能需要进行广泛的校准。 通过避免使用现有技术的功率检测器和增益控制元件，本发明基本上避免了上述问题。
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公开(公告)号：US5933771A
公开(公告)日：1999-08-03
申请号：US879771
申请日：1997-06-20
CPC分类号： H03G1/0023 , H03D7/1433 , H03D7/1441 , H03D7/1458 , H03D2200/0025 , H03D2200/0043
摘要： The functionality of a variable gain controlled amplifier and a tree mixer are combined to provide a variable gain controlled mixer. In constructing the combination, both the current-to-voltage conversion output stage of the mixer, and the voltage-to-current conversion input stage of the variable gain amplifier are removed. Both the variable gain stage and the mixing stage are connected in parallel to modify the input current. Other configurations are provided, including a single balanced mixer, and a folded mixer.
摘要翻译： 可变增益控制放大器和树混合器的功能被组合以提供可变增益控制混频器。 在组合时，混合器的电压 - 电压转换输出级和可变增益放大器的电压 - 电流转换输入级都被去除。 并联连接可变增益级和混合级，修改输入电流。 提供了其他配置，包括单个平衡混合器和折叠混合器。
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公开(公告)号：US20190140623A1
公开(公告)日：2019-05-09
申请号：US15808603
申请日：2017-11-09
IPC分类号： H03H11/24
CPC分类号： H03H11/245 , H03F3/19 , H03F2200/451 , H03G3/3042
摘要： A control circuit is disclosed for controlling operation of a radio frequency (RF) transistor. The control circuit has a first sub-circuit that accepts a reference voltage and a reference current. The control circuit has a second sub-circuit with a plurality of stacked transistors coupled between the first sub-circuit and ground, and a resistor ladder coupled between the first sub-circuit and an output port of the control circuit. The first sub-circuit provides the reference current to flow through the stacked transistors, and sets a total voltage drop across the stacked transistors equal to the reference voltage. The first sub-circuit also sets a total voltage drop across the resistor ladder equal to the reference voltage. Each rung of the resistor ladder is coupled to control an operating voltage of a stacked transistor, to cause each stacked transistor to operate with similar control conditions.
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公开(公告)号：US5920235A
公开(公告)日：1999-07-06
申请号：US882577
申请日：1997-06-25
CPC分类号： H03B5/1231 , H03B5/1215 , H03B5/1243 , H03B2202/04 , H03B2202/073 , H03B2202/076
摘要： A voltage controlled oscillator has a cross-coupled negative resistance cell formed as an integrated circuit connected to off-chip components of a high-Q resonant tank circuit. To counteract spurious oscillations brought about by package parasitics caused by the interconnection of the chip to the external components, the cell is provided with a degeneration impedance. Typically, a pure inductor is used if all the elements of the tank circuit are off-chip. In a case where the tank circuit includes an on-chip fixed capacitor, the degeneration impedance may take the form of a capacitor.
摘要翻译： 压控振荡器具有交叉耦合负电阻单元，其形成为连接到高Q谐振回路的芯片外部件的集成电路。 为了抵消由芯片与外部组件的互连引起的封装寄生效应引起的寄生振荡，电池被提供了退化阻抗。 通常，如果储能电路的所有元件都是芯片外的，则使用纯电感。 在储能电路包括片上固定电容器的情况下，退化阻抗可以采取电容器的形式。
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公开(公告)号：US10418973B2
公开(公告)日：2019-09-17
申请号：US15808603
申请日：2017-11-09
摘要： A control circuit is disclosed for controlling operation of a radio frequency (RF) transistor. The control circuit has a first sub-circuit that accepts a reference voltage and a reference current. The control circuit has a second sub-circuit with a plurality of stacked transistors coupled between the first sub-circuit and ground, and a resistor ladder coupled between the first sub-circuit and an output port of the control circuit. The first sub-circuit provides the reference current to flow through the stacked transistors, and sets a total voltage drop across the stacked transistors equal to the reference voltage. The first sub-circuit also sets a total voltage drop across the resistor ladder equal to the reference voltage. Each rung of the resistor ladder is coupled to control an operating voltage of a stacked transistor, to cause each stacked transistor to operate with similar control conditions.
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公开(公告)号：US06529721B1
公开(公告)日：2003-03-04
申请号：US09325903
申请日：1999-06-04
申请人： Samuel Alfred Tiller
发明人： Samuel Alfred Tiller
IPC分类号： H04B126
CPC分类号： H03D7/1425 , H03D7/1433 , H03D7/1441 , H03D7/1458 , H03D7/1491 , H03D2200/0023 , H03D2200/0043
摘要： A mixer circuit for downconverting a radio frequency signal to a lower (intermediate) frequency signal or upconverting an intermediate frequency signal to a radio frequency signal. The mixer circuit in downconversion mode has a single-ended radio frequency input and an intermediate frequency output. A transistor is provided that has a base that receives the radio frequency input, a collector, and a common emitter. A transformer is provided that has a primary winding AC coupled to ground and first and second secondary windings. The collector of the transistor is coupled to the primary winding. A first transistor pair and a second transistor pair are provided, each having a first and second transistor, and each transistor having a base, a collector and an emitter. The emitters of the first transistor pair are coupled together and to the first secondary winding of the transformer. The emitters of the second transistor pair are coupled together and to the second secondary winding of the transformer. Detailed connections, see FIGS. 1-6. In upconversion mode, the intermediate frequency signal is input to the transistor instead of the radio frequency signal.
摘要翻译： 一种用于将射频信号下变频到较低（中间）频率信号或将中频信号上变频到射频信号的混频器电路。 下变频模式的混频器电路具有单端射频输入和中频输出。 提供了具有接收射频输入的基极，集电极和公共发射极的晶体管。 提供了一种变压器，其具有耦合到地和初级和次级绕组的初级绕组AC。 晶体管的集电极耦合到初级绕组。 提供第一晶体管对和第二晶体管对，每个具有第一和第二晶体管，并且每个晶体管具有基极，集电极和发射极。 第一晶体管对的发射极耦合到变压器的第一次级绕组。 第二晶体管对的发射极耦合在一起并连接到变压器的第二次级绕组。 详细的连接，见图 1-6。 在上变频模式中，中频信号被输入到晶体管而不是射频信号。
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