公开(公告)号：US20030158729A1

公开(公告)日：2003-08-21

申请号：US10076086

申请日：2002-02-15

申请人： Radiodetection Limited

发明人： John Mark Royle ,  James Ian King ,  Richard David Pearson

IPC分类号： G10L019/14

CPC分类号： H04R5/04 ,  G10K15/02

摘要： Methods and systems for digitally generating sound from phase and amplitude information of a narrow bandwidth signal, such as a narrow bandwidth locator signal. Phase-derivative information is determined from the phase information. The bandwidth of the phase-derivative information is spread out, or stretched, over a wider bandwidth, so that the frequency variations will be more perceptible to users. The result is combined with an audio band carrier frequency, the result of which controls an oscillator. The oscillator output is combined with the amplitude information to generate an analog audio signal that is modulated with the amplitude information and the phase-derivative information. The amplitude information wider bandwidth phase-derivative information are used to modulate an audio carrier in both frequency and amplitude. The overall process can be thought of as a translation of the frequency and amplitude information from the narrow bandwidth around the locate frequency to a wider bandwidth on a chosen carrier frequency in the audio band. The received amplitude and phase information is received at an input sample rate. Where the input sample rate is relatively low, the amplitude and phase information are up-sampled to an output sample rate that is higher than a desired audio frequency. The higher output sample rate insures that there are sufficient samples of the signal during each cycle or period of the audio frequency. The higher sample rate is typically also the sample rate of a digital to analog converter that outputs an analog signal to a speaker. The amplitude information and/or phase derivative information are optionally scaled to system gain. The sound heard by the operator can optionally be adjusted with an optional selectivity filter.

摘要翻译： 用于从诸如窄带宽定位信号的窄带宽信号的相位和振幅信息中数字产生声音的方法和系统。 从相位信息确定相位导数信息。 相位导数信息的带宽在更宽的带宽上扩展或拉伸，使得频率变化对于用户来说将更为可见。 结果与音频载波频率相结合，其结果控制振荡器。 振荡器输出与幅度信息组合，以产生用振幅信息和相位导数信息调制的模拟音频信号。 振幅信息较宽的带宽相位微分信息用于调制频率和幅度的音频载波。 整个过程可以被认为是频率和幅度信息从定位频率周围的窄带宽到音频频带中所选择的载波频率上的较宽带宽的转换。 接收的幅度和相位信息以输入采样率被接收。 在输入采样率相对低的情况下，幅度和相位信息被上采样到高于期望音频的输出采样率。 较高的输出采样率确保在每个周期或音频周期期间有足够的信号样本。 更高的采样率通常也是将模拟信号输出到扬声器的数模转换器的采样率。 幅度信息和/或相位导数信息可选地被缩放到系统增益。 操作员听到的声音可以选择性地用可选的选择性过滤器进行调节。