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公开(公告)号：US4562414A
公开(公告)日：1985-12-31
申请号：US565947
申请日：1983-12-27
CPC分类号： H03C3/0983 , H03C3/0933 , H03C3/0941
摘要： There is disclosed a new and improved frequency modulation system and method for providing a frequency modulated signal which varies in frequency from a center frequency in response to the amplitude of an analog modulating signal. The system and method utilizes a frequency shift synthesizer to provide the frequency modulated signal and digital techniques for quantizing the amplitude modulating signal and providing dividing factors to the frequency shift synthesizer responsive to the amplitude quantization.
摘要翻译： 公开了一种新的改进的频率调制系统和方法，用于响应于模拟调制信号的振幅，提供频率随中心频率变化的频率调制信号。 该系统和方法利用频移合成器提供频率调制信号和用于量化幅度调制信号的数字技术，并且响应于幅度量化向频移合成器提供分频因子。
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公开(公告)号：US4977616A
公开(公告)日：1990-12-11
申请号：US428429
申请日：1989-10-26
IPC分类号： H04B7/08
CPC分类号： H04B7/0814 , H04B7/0808 , H04B7/0811
摘要： An antenna switch control circuit for use in achieving antenna selection diversity in TDM RF receivers. RSSI for at least one antenna is monitored during time slots containing information not of interest. This information can then be compared with other antenna performance information to allow a selection to be made such that the receiver generally operates with the antenna receiving the strongest signal. In one embodiment, all possible antennas are monitored during a time slot containing information not of interest. In another embodiment, RSSI for the selected antenna can be monitored during the time slot of interest, such that antenna selection can again be varied should the selected antenna diminish in performance.
摘要翻译： 一种天线切换控制电路，用于实现TDM射频接收机中的天线选择分集。 在包含不感兴趣的信息的时隙期间监视至少一个天线的RSSI。 然后可以将该信息与其他天线性能信息进行比较，以允许进行选择，使得接收机通常以接收最强信号的天线进行操作。 在一个实施例中，在包含不感兴趣的信息的时隙期间监视所有可能的天线。 在另一个实施例中，可以在感兴趣的时隙期间监视所选天线的RSSI，使得如果所选天线的性能降低，天线选择可以再次变化。
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3.发明授权Method, device, wireless transceiver and computer for providing collision detection in wireless carrier sense multiple access systems 失效用于在无线载波侦听多路访问系统中提供冲突检测的方法，设备，无线收发器和计算机
公开(公告)号：US5940400A
公开(公告)日：1999-08-17
申请号：US743685
申请日：1996-11-06
IPC分类号： H04B1/10 , H04L12/28 , H04L12/413
CPC分类号： H04L12/40032 , H04L12/413 , H04W74/0858
摘要： A method (600), device, wireless transceiver, computer and personal digital assistant (300, 400) provide collision presence detection in wireless intensity-modulated binary-coded data transceivers which is compatible with the collision detection employed in IEEE standard 10BASE-T Ethernet. A measurement of the degree of correlation which exists between the signal transmitted and the signal received provides a basis for efficient collision detection in CSMA systems.
摘要翻译： 一种方法（600），设备，无线收发器，计算机和个人数字助理（300,400）在无线强度调制二进制编码数据收发器中提供冲突存在检测，其与IEEE标准10BASE-T以太网中采用的冲突检测兼容 。 存在于所发送的信号和所接收的信号之间的相关程度的测量为CSMA系统中的有效冲突检测提供了依据。
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公开(公告)号：US4754450A
公开(公告)日：1988-06-28
申请号：US843882
申请日：1986-03-25
CPC分类号： H04B1/66 , H04J3/1688
摘要： A time division multiplexed (TDM) communication system is disclosed, which apportions radio frequency communication channels into at least two time slots. Voice signals for transmission on this system are analyzed and vo-coded into a digital signal that is transmitted during one or more of the time slots. Received messages are recovered from at least one of these time slots and the voice message synthesized from the vo-coded signal. In this manner multiple voice messages may be transceived in a time division multiplexed manner on a single narrowband communication channel.
摘要翻译： 公开了一种时分复用（TDM）通信系统，其将射频通信信道分配到至少两个时隙。 用于在该系统上传输的语音信号被分析并且被vo编码成在一个或多个时隙期间发送的数字信号。 从这些时隙中的至少一个和从VoIP编码信号合成的语音消息中恢复接收到的消息。 以这种方式，可以在单个窄带通信信道上以时分复用方式收发多个语音消息。
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5.发明授权Apparatus and method for generating filtered multilevel data from NRZ data 失效从NRZ数据生成滤波后的多级数据的装置和方法
公开(公告)号：US4618941A
公开(公告)日：1986-10-21
申请号：US533484
申请日：1983-09-19
申请人： Donald L. Linder , Scott N. Carney
发明人： Donald L. Linder , Scott N. Carney
CPC分类号： H03H17/06 , H04B1/62 , H04L25/4917
摘要： An embodiment of the invention includes a binary linear phase response filter having a plurality of weighted outputs and a summing circuit which sums groups of the weighted outputs. A polarity inverting mechanism is provided for selectively changing the polarity of the summed outputs from the summing circuit means. An encoding circuit controls the polarity selection in accordance with the logic rule for converting non-return to zero (NRZ) data into return to zero data. Another summing circuit sums the outputs of the polarity inverting mechanism and provides a filtered multilevel data output.
摘要翻译： 本发明的实施例包括具有多个加权输出的二进制线性相位响应滤波器和对加权输出的组进行求和的求和电路。 提供极性反转机构，用于选择性地改变来自求和电路装置的求和输出的极性。 编码电路根据用于将不归零（NRZ）数据转换成零数据的逻辑规则控制极性选择。 另一个求和电路将极性反转机构的输出相加并提供滤波后的多电平数据输出。
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公开(公告)号：US3962553A
公开(公告)日：1976-06-08
申请号：US518827
申请日：1974-10-29
摘要： A battery saving system for a portable duplex communications system such as a portable telephone system includes a voice operated transmitter within each portable unit which automatically transmits radio signals upon application of audio signals thereto and discontinues transmission upon termination of the audio signals to conserve battery power. A companion receiver includes a fast acting squelch system to substantially eliminate the noise bursts occurring between transmissions by said portable unit.
摘要翻译： 用于诸如便携式电话系统的便携式双工通信系统的电池节省系统包括在每个便携式单元内的语音操作的发射机，其在施加音频信号时自动发送无线电信号，并且在音频信号终止时中止传输以节省电池电力。 伴随接收机包括快速静噪系统，以基本上消除由所述便携式单元发射之间发生的噪声突发。
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7.发明授权FM communication system with improved response to Rayleigh-faded companded signals 失效FM通信系统对瑞利衰落的压缩信号的响应改善
公开(公告)号：US4893347A
公开(公告)日：1990-01-09
申请号：US90982
申请日：1987-08-28
CPC分类号： H03G3/3052 , H03G3/344 , H03G3/345 , H04B1/1027 , H04H20/67
摘要： An improved FM companding communication system is disclosed in which noise bursts and pops in the audio output of the receiver, due to weak and Rayleigh-faded signals, are minimized by selectively attenuating the audio signal in the receiver prior to expansion. The amount and rate of attenuation for the noise reduction circuits is determined by a control signal derived from either the average discriminator noise at frequencies above 3 kHz, or from a received RF signal strength indicator, or a combination of both. The audio output is attenuated during weak signals or Rayleigh fades only when the attenuation control signal increases above a predetermined signal-to-noise ratio threshold. Preferably, attenuation increases at a rate greater than the decrease in the received signal strength. The invention includes a circuit for modifying the expansion characteristics of the expandor to minimize signal clipping in the output audio stage of the receiver due to limited dynamic range.
摘要翻译： 公开了一种改进的FM压扩通信系统，其中由于弱和瑞利衰落的信号，接收机的音频输出中的噪声突发和流行通过在扩展之前选择性地衰减接收机中的音频信号来最小化。 噪声降低电路的衰减量和速率由通过频率高于3kHz的平均鉴别器噪声或接收到的RF信号强度指示符或两者的组合导出的控制信号确定。 只有当衰减控制信号增加到高于预定的信噪比阈值时，音频输出在弱信号或瑞利衰减期间被衰减。 优选地，衰减以大于接收信号强度的降低的速率增加。 本发明包括用于修改扩展器的扩展特性的电路，以使接收机的输出音频级中的信号限幅最小化，这是由于有限的动态范围。
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8.发明授权Automatic frequency control circuit having an equalized closed loop frequency response 失效自动频率控制电路具有均衡的闭环频率响应
公开(公告)号：US4601061A
公开(公告)日：1986-07-15
申请号：US627159
申请日：1984-07-02
申请人： Scott N. Carney , Donald L. Linder
发明人： Scott N. Carney , Donald L. Linder
CPC分类号： H03J7/04
摘要： An AFC circuit may include an oscillator having an output frequency responsive to a derived error signal, a mixer for mixing a received signal with the output of the oscillator to produce an intermediate frequency, and a signal recovery detector for recovering the information carried by the intermediate frequency. An integral loop filter and compensation circuit receives the recovered signal from the detector, provides a compensated recovery signal which is independent of the closed loop frequency response of the AFC circuit, and provides an error signal which controls the oscillator.
摘要翻译： AFC电路可以包括具有响应于导出的误差信号的输出频率的振荡器，用于将接收信号与振荡器的输出混合以产生中频的混频器，以及用于恢复由中间信号携带的信息的信号恢复检测器 频率。 积分环路滤波器和补偿电路从检测器接收恢复的信号，提供与AFC电路的闭环频率响应无关的经补偿的恢复信号，并提供控制振荡器的误差信号。
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公开(公告)号：US4581749A
公开(公告)日：1986-04-08
申请号：US627158
申请日：1984-07-02
CPC分类号： H03C3/0983 , H03C3/0941 , H03C3/0966 , H04L27/2017 , H03C2200/005
摘要： An automatic deviation control circuit for an angle modulated data transmitter is disclosed wherein the deviation level of modulated data is controlled by a modulation cancelling deviation error detection feedback loop. After the modulation is cancelled from a sample of modulated carrier by a predetermined value of deviation, residual modulation is detected, sampled following a predetermined number of like-level data bits, and applied to the modulation path gain to increase or decrease the deviation such that the residual modulation is minimized.
摘要翻译： 公开了一种用于角度调制数据发射机的自动偏差控制电路，其中调制数据的偏移电平由调制消除偏差误差检测反馈回路控制。 在从调制载波的采样中取消了预定的偏差值的调制之后，检测到残留调制，按照预定数量的同级数据比特进行采样，并将其应用于调制路径增益以增加或减少偏差，使得 残余调制被最小化。
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