Spread spectrum digital data communication overlay system and method
    2.
    发明授权
    Spread spectrum digital data communication overlay system and method 失效
    扩频数字数据通信覆盖系统及方法

    公开(公告)号:US06865215B1

    公开(公告)日:2005-03-08

    申请号:US09505463

    申请日:2000-02-16

    IPC分类号: H04B1/707 H04B1/713 H04B7/26

    摘要: A digital data communication overlay system is disclosed which is overlaid on a predefined frequency band of an existing analog data communication system. The digital data communication overlay system comprises a digital mobile unit and a digital ground station. The digital mobile unit and the digital ground station are configured to transmit and receive spread spectrum digital data communication signals between each other over the same spread spectrum digital channel. This is done by spreading the spread spectrum digital data communication signals over the predefined frequency spectrum of the existing analog data communication system.

    摘要翻译: 公开了覆盖在现有模拟数据通信系统的预定义频带上的数字数据通信覆盖系统。 数字数据通信覆盖系统包括数字移动单元和数字地面站。 数字移动单元和数字地面站被配置为通过相同的扩频数字信道在彼此之间发送和接收扩频数字数据通信信号。 这是通过在现有模拟数据通信系统的预定义频谱上扩展扩频数字数据通信信号来完成的。

    Direct-sequence spread-spectrum ultrasonic testing device
    3.
    发明授权
    Direct-sequence spread-spectrum ultrasonic testing device 失效
    直接序列扩频超声波检测装置

    公开(公告)号:US5461921A

    公开(公告)日:1995-10-31

    申请号:US91179

    申请日:1993-07-13

    摘要: Techniques for providing an ultrasonic flaw detection system are disclosed. A continuous wave of wide-band direct-sequence spread-spectrum signals continuously drives one or more transmitting transducers, thereby flooding a test object with coded ultrasound. In operation, the ultrasonic testing system is capable of reliably and predictably transmitting a high degree of ultrasonic energy (power) to a test object. Code division multiplexing correlation techniques using a variably delayed replica of a selected segment of the DSSS signal are applied to the signals received by the receiving transducers to generate a signature representing the signal returned from all reflectors within the test object.

    摘要翻译: 公开了一种用于提供超声波探伤系统的技术。 宽带直接序列扩频信号的连续波连续地驱动一个或多个发射换能器,从而通过编码超声波淹没测试对象。 在操作中,超声波测试系统能够可靠且可预测地将高度的超声波能量(功率)传输到测试对象。 使用DSSS信号的所选段的可变延迟副本的码分复用相关技术被应用于由接收换能器接收的信号,以产生表示从测试对象内的所有反射器返回的信号的签名。

    Communication device, apparatus, and method utilizing pseudonoise signal
for acoustical echo cancellation
    4.
    发明授权
    Communication device, apparatus, and method utilizing pseudonoise signal for acoustical echo cancellation 失效
    利用伪噪声信号进行声学回波消除的通信装置,装置和方法

    公开(公告)号:US5327496A

    公开(公告)日:1994-07-05

    申请号:US85749

    申请日:1993-06-30

    摘要: A communication device, an apparatus, and a method for acoustic echo cancellation which makes use of a pseudonoise signal. An audio mixer adds the pseudonoise signal to an input signal received from another communication device to produce a first composite signal. An audio system converts the first composite signal to sound in an at least partially enclosed space. The at least partially enclosed space produces an acoustical echo in response. The audio system then converts the acoustical echo and other sounds in the at least partially enclosed space to a second composite signal. A signal processor cross-correlates the second composite signal with the pseudonoise signal to produce an estimate of the overall impulse response of the combined system formed by the at least partially enclosed space and the audio system. The processor then convolves the first composite signal with the impulse response estimate to produce an echo estimation signal. The echo estimation signal is an estimate of the component of the second composite signal which corresponds to the acoustical echo. The processor then subtracts the echo estimation signal from the second composite signal to produce an output signal.

    摘要翻译: 一种使用伪噪声信号的通信设备,装置和用于声学回声消除的方法。 音频混合器将伪噪声信号添加到从另一通信设备接收的输入信号以产生第一复合信号。 音频系统将第一复合信号转换成至少部分封闭的空间中的声音。 至少部分封闭的空间产生响应的声学回波。 然后,音频系统将至少部分封闭空间中的声学回声和其他声音转换为第二复合信号。 信号处理器将第二复合信号与伪噪声信号相互相关,以产生由至少部分封闭的空间和音频系统形成的组合系统的总脉冲响应的估计。 然后处理器将第一复合信号与脉冲响应估计进行卷积,以产生回波估计信号。 回波估计信号是对应于声学回波的第二复合信号的分量的估计。 然后,处理器从第二复合信号中减去回波估计信号以产生输出信号。

    Pre-distorter and corresponding method for deriving same
    5.
    发明授权
    Pre-distorter and corresponding method for deriving same 失效
    预失真和相应的推导方法

    公开(公告)号:US06377116B1

    公开(公告)日:2002-04-23

    申请号:US09566642

    申请日:2000-05-08

    IPC分类号: H03F126

    CPC分类号: H03F1/3241

    摘要: A method of deriving a pre-distorter for a corresponding non-linear amplifier is disclosed. The first step of the method is to form the pre-distorter's topology. This is done by first determining a corresponding inverse topology to the non-linear amplifier's topology. The non-linear amplifier has a topology comprising filter and non-linear amplifier elements. The inverse topology comprises corresponding inverse filter and amplifier elements to the amplifier's filter and non-linear amplifier elements. Then, those of the inverse filter and amplifier elements for which compensation with the pre-distorter is desired are selected. Any of the inverse filter and amplifier elements that were not selected are then removed from the inverse topology to form the pre-distorter's topology. Thus, the pre-distorter's topology comprises the selected inverse filter and amplifier elements. After the pre-distorter's topology is determined, a predefined input signal is applied to the non-linear amplifier. In response, measurements of selected signals of the non-linear amplifier are made. Once the measurements are made, coefficients that define the selected inverse filter and amplifier elements' are estimated. This is done in response to the measurements that were made.

    摘要翻译: 公开了一种导出相应非线性放大器的预失真器的方法。 该方法的第一步是形成预失真器的拓扑。 这是通过首先确定与非线性放大器的拓扑的对应的逆拓扑来完成的。 非线性放大器具有包括滤波器和非线性放大器元件的拓扑。 反向拓扑包括放大器滤波器和非线性放大器元件的对应的反相滤波器和放大器元件。 然后,选择需要与预失真器进行补偿的反相滤波器和放大器元件的那些。 然后从逆拓扑中除去未选择的任何反向滤波器和放大器元件以形成预失真器的拓扑。 因此,预失真器的拓扑结构包括所选择的反向滤波器和放大器元件。 在确定预失真器的拓扑结构之后,将预定义的输入信号应用于非线性放大器。 作为响应,进行非线性放大器的选定信号的测量。 一旦进行了测量,就可以估计定义所选择的反相滤波器和放大器元件的系数。 这是为了响应所做的测量而完成的。

    Communication device apparatus and method utilizing pseudonoise signal
for acoustical echo cancellation
    6.
    再颁专利
    Communication device apparatus and method utilizing pseudonoise signal for acoustical echo cancellation 失效
    利用伪噪声信号进行回声消除的通信装置及方法

    公开(公告)号:USRE35574E

    公开(公告)日:1997-07-29

    申请号:US447686

    申请日:1995-05-23

    摘要: A communication device, an apparatus, and a method for acoustic echo cancellation which makes use of a pseudonoise signal. An audio mixer adds the pseudonoise signal to an input signal received from another communication device to produce a first composite signal. An audio system converts the first composite signal to sound in an at least partially enclosed space. The at least partially enclosed space produces an acoustical echo in response. The audio system then converts the acoustical echo and other sounds in the at least partially enclosed space to a second composite signal. A signal processor cross-correlates the second composite signal with the pseudonoise signal to produce an estimate of the overall impulse response of the combined system formed by the at least partially enclosed space and the audio system. The processor then convolves the first composite signal with the impulse response estimate to produce an echo estimation signal. The echo estimation signal is an estimate of the component of the second composite signal which corresponds to the acoustical echo. The processor then subtracts the echo estimation signal from the second composite signal to produce an output signal.

    摘要翻译: 一种使用伪噪声信号的通信设备,装置和用于声学回声消除的方法。 音频混合器将伪噪声信号添加到从另一通信设备接收的输入信号以产生第一复合信号。 音频系统将第一复合信号转换成至少部分封闭的空间中的声音。 至少部分封闭的空间产生响应的声学回波。 然后,音频系统将至少部分封闭空间中的声学回声和其他声音转换为第二复合信号。 信号处理器将第二复合信号与伪噪声信号相互相关,以产生由至少部分封闭的空间和音频系统形成的组合系统的总脉冲响应的估计。 然后处理器将第一复合信号与脉冲响应估计进行卷积,以产生回波估计信号。 回波估计信号是对应于声学回波的第二复合信号的分量的估计。 然后,处理器从第二复合信号中减去回波估计信号以产生输出信号。