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1. 发明授权

US06034573A Method and apparatus for calibrating modulation sensitivity 失效
标题翻译：用于校准调制灵敏度的方法和装置
公开(公告)号：US06034573A
公开(公告)日：2000-03-07
申请号：US961400
申请日：1997-10-30
申请人： Martin Alderton
发明人： Martin Alderton
IPC分类号： H03D7/16 , H03C3/08
CPC分类号： H03D7/161
摘要： A method and apparatus for continuously calibrating the modulation sensitivity of a voltage controlled oscillator (VCO) within a modulator of a transmitter. In accordance with the present invention, the transmitter is coupled to the receiver in order to loop back the transmit signal. The present invention includes a baseband signal generator which generates a reference baseband signal of known amplitude during periods when no other baseband information is being applied to the transmitter by the user. A Signal and Reference Comparison Circuit (SRCC) receives the output from the demodulator and determines whether the VCO within the transmitter has the proper modulation sensitivity. If the modulation sensitivity of the VCO is not within a desired range, then a signal generated by the SRCC is applied to a baseband level control circuit to adjust the level of the baseband signal that is applied to the VCO.
摘要翻译：一种用于连续校准发射机调制器内的压控振荡器（VCO）的调制灵敏度的方法和装置。根据本发明，发射机耦合到接收机以便回传发射信号。本发明包括基带信号发生器，其在没有其他基带信息被用户向发射机应用的时段期间产生已知幅度的参考基带信号。信号和参考比较电路（SRCC）接收解调器的输出，并确定发射机内的VCO是否具有适当的调制灵敏度。如果VCO的调制灵敏度不在期望的范围内，则由SRCC产生的信号被施加到基带电平控制电路以调整施加到VCO的基带信号的电平。

2. 发明授权

US06025758A Method and apparatus for performing digital data signal modulation 失效
标题翻译：用于执行数字数据信号调制的方法和装置
公开(公告)号：US06025758A
公开(公告)日：2000-02-15
申请号：US961392
申请日：1997-10-30
申请人： Keh-Shehn Lu
发明人： Keh-Shehn Lu
IPC分类号： H04L25/03 , H04L27/20 , H04L27/28 , H04L27/10
CPC分类号： H04L27/2017 , H04L25/03834
摘要： The present invention includes a method for generating a GMSK modulating signal from a serial digital data bit stream whereby the GMSK modulating signal modulates a carrier frequency signal associated with a GMSK transmitter of a digital communications system. Specifically, the method includes converting each set of m consecutive data bits of the bit stream into a parallel symbol, whereby there are 2.sup.m possible symbols. Each symbol is generally defined as (B.sub.-(m-1). . . B.sub.0), where B.sub.0 is the current data bit and B.sub.-(m-1) is the mth previous data bit with respect to B.sub.0. Next, a corresponding phase advance is assigned to each of the 2.sup.m symbols, each phase advance being substantially equivalent to a percent phase advance contributed by the m consecutive data bits of each symbol. Also, four corresponding accumulated phases are assigned to each of the 2.sup.m symbols, each accumulated phase being derived from a multiple of 90 degrees. Still further, digitally represented waveform portions are stored in a memory unit, each waveform portion respectively representing a time varying waveform that advances in phase by an amount respectively equal to each of the four accumulated phases. Next, the phase advance assigned to the current symbol is added to the phase advance accumulated from the previous symbol to yield a current accumulated phase for the current symbol. The memory unit is searched for the waveform portion that corresponds to the current accumulated phase and the portion is then outputted from the memory unit. The adding, searching and outputting steps are performed for each data bit of the digital data bit stream to form a digital representation of the GMSK modulating signal.
摘要翻译：本发明包括一种用于从串行数字数据比特流产生GMSK调制信号的方法，由此GMSK调制信号调制与数字通信系统的GMSK发射机相关联的载波频率信号。具体地说，该方法包括将比特流的每个m个连续的数据比特组转换为并行符号，由此有2m个可能的符号。每个符号通常定义为（B-（m-1）... B0），其中B0是当前数据位，B（m-1）是相对于B0的第m个前一个数据位。接下来，将相应的相位前进分配给每个2m个符号，每个相位提前基本上等于由每个符号的m个连续数据位贡献的百分比相位提前。另外，对于2m个符号中的每一个分配四个相应的累积相位，每个累积相位从90度的倍数导出。另外，数字表示的波形部分存储在存储单元中，每个波形部分分别表示时相波形，该时变波形相当于四个累加相中的每一个相位相等的量。接下来，将分配给当前符号的相位前进相加到从先前符号累积的相位提前，以产生当前符号的当前累积相位。搜索存储器单元对应于当前累积相位的波形部分，然后从存储器单元输出该部分。对数字数据位流的每个数据位进行加法，搜索和输出步骤，以形成GMSK调制信号的数字表示。

3. 发明授权

US6005756A Effective grounding of a circuit at RF and IF 失效
标题翻译： RF和IF电路的有效接地
公开(公告)号：US6005756A
公开(公告)日：1999-12-21
申请号：US977785
申请日：1997-11-25
申请人： Mark Lane
发明人： Mark Lane
IPC分类号： H03H7/01 , H02H3/00
CPC分类号： H03H7/0115 , H03H7/1791
摘要： A circuit for grounding a signal at a first frequency and at a second frequency. The circuit includes a first capacitor and an inductor in series and a second capacitor in parallel with the first capacitor and inductor. The first capacitor is series resonant at the first frequency and the second capacitor is series resonant at the second frequency. The inductance of the inductor is selected so the combination of the packaging inductance of the first capacitor and the inductor parallel resonants with the second capacitor at a frequency lower than the second frequency and higher than the first frequency, where the second frequency is greater than the first frequency. The grounding circuit may be used to provide a second input to a balanced RF mixer where the RF mixer receives a RF signal at the second frequency at a first input and generates an IF signal at the first frequency.
摘要翻译：一种用于以第一频率和第二频率对信号进行接地的电路。该电路包括串联的第一电容器和电感器，以及与第一电容器和电感器并联的第二电容器。第一电容器在第一频率处串联谐振，第二电容器在第二频率处串联谐振。选择电感器的电感，使得第一电容器的封装电感和电感器的并联谐振与第二电容器的组合在比第二频率低的频率处并且高于第一频率，其中第二频率大于第一频率接地电路可以用于向平衡RF混频器提供第二输入，其中RF混频器在第一输入处以第二频率接收RF信号，并以第一频率产生IF信号。

4. 发明授权

US5956627A Temperature compensated power control circuit 失效
标题翻译：温度补偿功率控制电路
公开(公告)号：US5956627A
公开(公告)日：1999-09-21
申请号：US889318
申请日：1997-07-08
申请人： Jeffrey J. Goos
发明人： Jeffrey J. Goos
IPC分类号： H03G1/04 , H04Q7/20
CPC分类号： H03G1/04
摘要： A temperature compensation technique employing a directional coupler providing signals from a forward sample port to a detector circuit for providing a DC output representative of transmitted power. A temperature compensation circuit including a current source is coupled to a reverse sample port of the directional coupler for providing a compensating DC bias current via said coupler, to the detector circuit. The detector circuit and the temperature compensation circuit each include matched diodes and corresponding circuits for tracking temperature and offsetting the effects of temperature on the DC output of the detector circuit.
摘要翻译：一种采用定向耦合器的温度补偿技术，其提供从正向采样端口到检测器电路的信号，以提供表示发射功率的DC输出。包括电流源的温度补偿电路耦合到定向耦合器的反向采样端口，用于经由所述耦合器向检测器电路提供补偿DC偏置电流。检测器电路和温度补偿电路各自包括匹配的二极管和对应的电路，用于跟踪温度并抵消温度对检测器电路的直流输出的影响。

5. 发明授权

US6127894A High frequency shunt feedback amplifier topology 失效
标题翻译：高频分流反馈放大器拓扑
公开(公告)号：US6127894A
公开(公告)日：2000-10-03
申请号：US10094
申请日：1998-01-21
申请人： Martin Alderton
发明人： Martin Alderton
IPC分类号： H01L23/66 , H03F1/34 , H03F3/60 , H03F1/26
CPC分类号： H03F3/601 , H01L23/66 , H03F1/342 , H01L2223/6644 , H01L2223/665 , H01L2224/05553 , H01L2224/05599 , H01L2224/48091 , H01L2224/48227 , H01L2224/48464 , H01L2224/49171 , H01L2224/85399 , H01L24/48 , H01L24/49 , H01L2924/00014 , H01L2924/01019 , H01L2924/01029 , H01L2924/01078 , H01L2924/14 , H01L2924/1423 , H01L2924/15153 , H01L2924/1517 , H01L2924/19041 , H01L2924/19107 , H01L2924/3011 , H01L2924/30111
摘要： A shunt feedback circuit path for use in high frequency amplifiers fabricated as a transmission line coupled to ground at one end and coupled to the shunt feedback transmission line of the amplifier at the other end. The shunt feedback transmission line has a first and second resistive element and a first and second capacitive element. A quarter-wavelength transmission line is used to transform the impedance coupled to one end with respect to the other end. The impedance as seen from one end of the line is a function of the characteristic impedance of the line. Therefore, by selecting the characteristic impedance the transmission line can be used to affect the impedance of the feedback path so the transmission line appears as an inductor of reactance equal to the characteristic impedance of the quarter-wavelength transmission line and reduces the overall effective length of the feedback path.
摘要翻译：用于高频放大器的分路反馈电路路径，其制造为在一端耦合到地并且耦合到另一端的放大器的并联反馈传输线的传输线。并联反馈传输线具有第一和第二电阻元件以及第一和第二电容元件。四分之一波长传输线用于将耦合到一端的阻抗相对于另一端变换。从线路的一端看的阻抗是线路的特征阻抗的函数。因此，通过选择特性阻抗，可以使用传输线来影响反馈路径的阻抗，因此传输线作为等于四分之一波长传输线的特性阻抗的电抗器的电感器出现，并降低总体有效长度反馈路径。

6. 发明授权

US06064270A System and method for compensating for reference frequency drift in a communications system 失效
公开(公告)号：US06064270A
公开(公告)日：2000-05-16
申请号：US63812
申请日：1998-04-21
申请人： Robert Keith Douglas
发明人： Robert Keith Douglas
IPC分类号： H03J1/00 , H03J7/04 , H03L7/00
CPC分类号： H03J1/0066 , H03J7/04
摘要： A system for compensating for reference frequency drift in a communications system. The inventive system includes a frequency source for providing a reference frequency. An error determination circuit determines if the reference frequency is within a predetermined range of a desired reference frequency and provides an error signal in response thereto. A frequency correction circuit steps the reference frequency up and/or down by a predetermined amount in response to the error signal until the reference frequency is within the predetermined range of the desired reference frequency. In a specific embodiment, the predetermined amount is twice the short-term capture range of the reference frequency which corresponds to approximately four parts per million. The predetermined range is the short-term capture range or two parts per million. The predetermined range is dependent upon the reference frequency band in which the receiver can successfully receive and decode the receive signal. The frequency source includes a voltage-controlled temperature-compensated crystal oscillator (VC-TCXO). The error determination circuit is a processor connected to the receiver. The processor includes a short-term frequency drift detector/compensator that generates a first control voltage input to the VC-TCXO for correcting the reference frequency in response to the error signal. The processor further includes a digital signal processing circuit for processing signals received from the receiver and determining the error signal in response thereto. The frequency correction circuit includes a long-term frequency drift detector/compensator that generates a second control voltage that is input to the VC-TCXO for correcting the reference frequency in response to the signal. In a more specific embodiment, the long-term frequency drift detector receives a correction signal from the short-term frequency drift detector indicating if the short-term frequency drift detector was successful in adjusting the reference frequency to the desired reference frequency.

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