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1.发明授权A/D reference level adjustment circuit to maintain optimum dynamic range at the A/D 失效A / D参考电平调节电路，以保持A / D的最佳动态范围
公开(公告)号：US5675339A
公开(公告)日：1997-10-07
申请号：US509589
申请日：1995-07-31
CPC分类号： H03M1/1295
摘要： A method and circuit for controlling a reference voltage for an analog-to-digital converter having plural outputs includes a sensor for indicating when outputs from the A/D converter are at least a desired voltage, and a processor responsive to the sensor and connected to a digital-to-analog converter which provides a reference voltage for the A/D converter. The processor provides signals to the D/A converter which change the reference voltage. A logic unit in the processor increments an accumulator when either an I or a Q component in the A/D converter output is at least the desired voltage and decrements the accumulator when neither the I nor the Q component is at least the desired voltage. A counter may buffer the accumulator changes by using only several of the most significant bits of the counter to change the A/D converter reference voltage.
摘要翻译： 用于控制具有多个输出的模数转换器的参考电压的方法和电路包括用于指示何时来自A / D转换器的输出至少为期望电压的传感器，以及响应于传感器并连接到 为A / D转换器提供参考电压的数模转换器。 处理器向D / A转换器提供信号，D / A转换器改变参考电压。 当A / D转换器输出中的I或Q分量至少为所需电压时，处理器中的逻辑单元递增累加器，并且当I和Q分量至少不是所需电压时，累加器递减。 计数器可以通过仅使用计数器的最高有效位来改变A / D转换器参考电压来缓冲累加器的变化。
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公开(公告)号：US5694417A
公开(公告)日：1997-12-02
申请号：US509590
申请日：1995-07-31
申请人： Carl Andren , John Fakatselis , Perry W. Frogge , Leonard V. Lucas , Al Petrick , Jim Snell
发明人： Carl Andren , John Fakatselis , Perry W. Frogge , Leonard V. Lucas , Al Petrick , Jim Snell
CPC分类号： H04B1/7075 , H04B7/0811 , H04B1/709
摘要： A direct sequence spread spectrum receiver and method for acquiring radio-frequency signals is provided for acquiring data from signals which have been transmitted in a spread spectrum system. The receiver is capable of receiving short data bursts from transmitters without prior knowledge of the time or location of the transmission and rapidly acquiring the signal before continuing with reliable data demodulation. The system includes one or more antennae for receiving RF signals which may be selectively connected to provide the received signals to the system for processing, a quadrature demodulator for providing I and Q baseband signals to a digital baseband processor which includes A/D converters, dual correlators for despreading the digital I and Q signals, a cartesian to polar converter, a demodulator for demodulating the polar coordinate digital I and Q signals, and a data descrambler for obtaining a serial data stream which may be provided to a serial interface.
摘要翻译： 提供一种用于获取射频信号的直接序列扩频接收机和方法，用于从在扩频系统中发送的信号中获取数据。 接收机能够从发射机接收短数据脉冲串，而无需事先知道传输的时间或位置，并在继续进行可靠数据解调之前快速获取信号。 该系统包括用于接收RF信号的一个或多个天线，其可以选择性地连接以将接收到的信号提供给系统进行处理;正交解调器，用于向包括A / D转换器的数字基带处理器提供I和Q基带信号， 用于解扩数字I和Q信号的相关器，笛卡尔到极化转换器，用于解调极坐标数字I和Q信号的解调器，以及用于获得可提供给串行接口的串行数据流的数据解扰器。
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公开(公告)号：US5029184A
公开(公告)日：1991-07-02
申请号：US470199
申请日：1990-01-24
IPC分类号： H04K3/00
摘要： A low probability of intercept communication system (CCSK)--modulates information signals onto an inverse fast Fourier transformation of a large number of simultaneous frequencies that have been determined to be reasonably `quiet` within a given system bandwidth, so as to produce a time domain pulse waveform. The amplitude of each transmitted frequency is weighted. Within the receiver equipment of each participant in the system, the incoming pulse waveform produced by the inverse fast Fourier transformation mechanism at the source is coupled to a fast Fourier transform operator, so as to separate the time domain signal into a plurality of frequency components that contain the modulated data. These components are then convolved with a replica of the plurality of quiet channels to derive a time domain output waveform from which the data modulation can be identified and recovered. Even if a jamming threat is injected into one or more of the `quiet` channels that has been selected as a participating carrier, by virtue of the signal analysis and recovery process employed by each unit for incoming signals, jamming spikes are effectively excised.
摘要翻译： 拦截通信系统（CCSK）的低概率 - 将信息信号调制到已经被确定为在给定系统带宽内合理“安静”的大量同时频率的快速傅里叶逆变换，从而产生时域 脉搏波形。 每个发射频率的幅度被加权。 在系统中每个参与者的接收机设备内，由源上的快速傅里叶逆变换机构产生的输入脉冲波形耦合到快速傅里叶变换算子，以将时域信号分离成多个频率分量， 包含调制数据。 然后将这些组件与多个安静信道的副本进行卷积，以导出可以识别和恢复数据调制的时域输出波形。 即使将干扰威胁注入一个或多个已经被选为参与载体的“安静”信道，由于每个单元用于输入信号的信号分析和恢复过程，有效地切断了干扰峰值。
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4.发明授权Method of performing antenna diversity in spread spectrum in wireless local area network 有权在无线局域网中在扩频中执行天线分集的方法公开(公告)号：US06563858B1
公开(公告)日：2003-05-13
申请号：US09231608
申请日：1999-01-14
申请人： John Fakatselis , Leonard V. Lucas
发明人： John Fakatselis , Leonard V. Lucas
IPC分类号： H04B169
CPC分类号： H04L27/2332 , H04B1/707 , H04B1/709 , H04B7/08 , H04B7/0811 , H04L25/03057 , H04L25/03267 , H04L27/2273 , H04L2025/03401 , H04L2025/0349 , H04W84/12 , H04W88/02
摘要： A method of performing antenna diversity in a wireless spread spectrum communication system is disclosed. A spread spectrum phase shift keyed (PSK) packet signal having data symbols formed from high rate mode chips is received in each of two respective spaced antenna of a spread spectrum receiver. The bit sync peak sample is determined within the packet signal for each antenna. Predetermined bit sync samples are subtracted a predetermined number of chips on either side of the bit sync peak sample from the peak for each antenna. The antenna having the higher value obtained in the subtracting step accomplished for each antenna is selected.
摘要翻译： 公开了一种在无线扩频通信系统中执行天线分集的方法。 具有由高速率模式芯片形成的数据符号的扩频相移键控（PSK）分组信号被接收在扩展频谱接收机的两个相应间隔天线的每一个中。 在每个天线的分组信号内确定位同步峰值采样。 从位于每个天线的峰值的位同步峰值采样的任一侧减去预定位同步采样。 选择在每个天线完成的减法步骤中获得的具有较高值的天线。
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5.发明授权Mechanism for extracting hybrid (fh/ds) spread spectrum signals within multi-signal type environment 失效在多信号类型环境中提取混合（fh / ds）扩频信号的机制
公开(公告)号：US5363401A
公开(公告)日：1994-11-08
申请号：US23264
申请日：1993-02-25
CPC分类号： H04B1/7102 , H04B1/692 , H04B1/715 , H04B2001/7152
摘要： Identification and extraction of hybrid, frequency-hopped direct sequence pseudo noise (FH/DS), signals from a multiband signal environment is effected by a sequential signal processing technique which examines the distribution of the energy content within a prescribed sub-spectrum window that is iteratively scanned or `slides` across the overall signal spectrum of interest. Based upon this energy content distribution, in particular the extent to which a sub-spectrum window contains energy that exhibits significant conjugate phase symmetry associated with a direct spread signal, the inventive signal processing technique proceeds to emphasize the spectral composition of components of which hybrid signals are comprised and to deemphasize the spectral composition of signals other than those contained in hybrid signals. Potential hybrid signal candidates whose spectral composition has been emphasized are then selectively combined with the deemphasized signals to isolate and identify the hybrid signals.
摘要翻译： 混合式跳频直接序列伪噪声（FH / DS）的识别和提取，来自多频带信号环境的信号通过顺序信号处理技术来实现，该信号处理技术检查在规定的子频谱窗口内的能量含量的分布， 在感兴趣的整个信号频谱上迭代扫描或“幻灯片”。 基于该能量含量分布，特别是子频谱窗口包含显示与直接扩展信号相关联的显着共轭相位对称性的能量的程度，本发明的信号处理技术继续强调其混合信号的分量的频谱组成 被包含并且不强调混合信号中包含的信号以外的信号的频谱组成。 光谱组成被强调的潜在混合信号候选者然后选择性地与去加重的信号组合以分离和识别混合信号。
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