公开(公告)号：US20020097860A1

公开(公告)日：2002-07-25

申请号：US09767545

申请日：2001-01-22

Applicant: Cirrus Logic, Inc.

Inventor： Manoj Soman ,  Sachin Ghanekar ,  Rajendra Datar

IPC: H04M001/00 ,  H04M003/00

CPC classification number: H04Q1/4575

Abstract: A method of detecting frequency errors exceeding a predetermined limit in a sampled signal includes the step of determining a peak amplitude of the signal at a tone frequency for a first frame of samples of the sampled signals using a filter having a first amplitude versus frequency response. A peak amplitude of signal at the tone frequency is determined for a second frame of samples of the sampled signal using a filter having a second amplitude versus frequency response. A ratio between the peak amplitude of the first frame and the peak amplitude of the second frame is calculated and compared against a threshold to detect frequency errors exceeding the predetermined limit. Among other things, this method decouples the frequency error detection problem from the twist factor estimation problem.

Abstract translation: 一种在采样信号中检测超过预定极限的频率误差的方法包括以下步骤：使用具有第一幅度对频率响应的滤波器，确定采样信号的第一采样帧采样频率处的信号的峰值幅度。 使用具有第二幅度对频率响应的滤波器，对采样信号的第二采样帧确定音调频率处的信号的峰值幅度。 计算第一帧的峰值振幅与第二帧的峰值振幅之间的比率，并将其与阈值进行比较，以检测超过预定极限的频率误差。 除此之外，这种方法将频率误差检测问题与扭转因子估计问题相分离。