8.1 引言 8.3 A/D变换的量化效应 8.5 极限环振荡 8.4 乘积误差对数字滤波器有限字长运算的影响 8.6 系数量化对系数滤波器的影响

快速傅里叶变换（FFT)的出现推动了傅里叶分析的发展和应用。事实上，FFT不是一种新的变换，而是DFT的快速算法。线性卷和及离散傅里叶变换（DFT）是信号处理涉及最多的运算，DFT在相关、滤波及谱估计等方面已得到了广泛的应用。本章重点讨论FFT的基2算法、分裂基算法和使频域细化的线性调频Z变换(CZT)算法，同时，也讨论了卷和的快速算法。 7.1 概述 7.2 直接计算DFT存在的问题及改进的途径 7.3 Goertzel算法 7.4 按时间抽取(DIT)的基2 FFT算法 7.5 按频率抽取(DIF)的基2 FFT算法 7.6 进一步减少运算量的措施 7.7 按频率抽取(DIF)的基4 FFT算法 7.8 分裂基算法 7.9 线性卷和与线性相关的FFT算法 7.10 线性调频Z变换（CZT）

5.1 Digital Processing of Continuous-Time Signals Digital processing of a continuous-time signal involves the following basic steps: (1) Conversion of the continuous-time signal into discrete-time signal, ()Processing of the discrete-time signal, (3) Conversion of the processed discrete- time signal back into a continuous-time signal

一、系统函数 二、序列线性时不变系统的频率响应 三、无限脉冲响应系统和有限脉冲响应系统

3.1离散傅立叶变换的定义 DFT的定义 设x(n)是一个长度为M的有限长序列,则定义的N点离散傅立 叶变换为

6.1 Introduction The convolution sum description of an LTI discrete-time system can, in principle, be used to implement the system For an IR finite-dimensional system this approach is not practical as here the impulse response is of infinite length · However, direct implementation of the IIR finite-dimensional system is practica

Objective-Determination- of realizable transfer function G() approximating a given frequency response specification is an important step in the development of a digital filter If an IIR filter is desired, G() should be a stable real rational function Digital filter design is the process of deriving the transfer function G

1.1 Introduction Any problems about signal analyses and processing may be thought of letting signals trough systems. f(t) y(t) h(t) From f(t) and h(t), find y(t), Signal processing From f(t) and y(t), find h(t), System design From(t)andh(t), find(t), Signal reconstruction

Discrete-Time Signals: Time-Domain Representation Signals are represented as sequences of numbers, called samples Sample value of a typical signal or sequence denoted as x[n] with n being an integer in the range-∞≤n≤∞ ·x[n] defined only for integer values of and undefined for non-integer values

Stability Condition of a Discrete-Time LTI System · BIBO Stability Condition-A- discrete--time LTI system is BIBO stable if the output sequence {y[n]} remains bounded for any bounded input sequence{x[n]} A discrete-time LTI system is BIBO stable if and only if its impulse response sequence {h[n]} is absolutely summable