Discrete time signal-sequence离散时间信号系列共23页
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《信号与系统》专业术语中英文对照表第1章绪论信号(signal)系统(system)电压(voltage)电流(current)信息(information)电路(circuit)网络(network)确定性信号(determinate signal)随机信号(random signal)一维信号(one–dimensional signal)多维信号(multi–dimensional signal)连续时间信号(continuous time signal)离散时间信号(discrete time signal)取样信号(sampling signal)数字信号(digital signal)周期信号(periodic signal)非周期信号(nonperiodic(aperiodic)signal)能量(energy)功率(power)能量信号(energy signal)功率信号(power signal)平均功率(average power)平均能量(average energy)指数信号(exponential signal)时间常数(time constant)正弦信号(sine signal)余弦信号(cosine signal)振幅(amplitude)角频率(angular frequency)初相位(initial phase)周期(period)频率(frequency)欧拉公式(Euler’s formula)复指数信号(complex exponential signal)复频率(complex frequency)实部(real part)虚部(imaginary part)抽样函数Sa(t)(sampling(Sa)function)偶函数(even function)奇异函数(singularity function)奇异信号(singularity signal)单位斜变信号(unit ramp signal)斜率(slope)单位阶跃信号(unit step signal)符号函数(signum function)单位冲激信号(unit impulse signal)广义函数(generalized function)取样特性(sampling property)冲激偶信号(impulse doublet signal)奇函数(odd function)偶分量(even component)奇分量(odd component)正交函数(orthogonal function)正交函数集(set of orthogonal function)数学模型(mathematics model)电压源(voltage source)基尔霍夫电压定律(Kirchhoff’s voltage law(KVL))电流源(current source)连续时间系统(continuous time system)离散时间系统(discrete time system)微分方程(differential function)差分方程(difference function)线性系统(linear system)非线性系统(nonlinear system)时变系统(time–varying system)时不变系统(time–invariant system)集总参数系统(lumped–parameter system)分布参数系统(distributed–parameter system)偏微分方程(partial differential function)因果系统(causal system)非因果系统(noncausal system)因果信号(causal signal)叠加性(superposition property)均匀性(homogeneity)积分(integral)输入–输出描述法(input–output analysis)状态变量描述法(state variable analysis)单输入单输出系统(single–input and single–output system)状态方程(state equation)输出方程(output equation)多输入多输出系统(multi–input and multi–output system)时域分析法(time domain method)变换域分析法(transform domain method)卷积(convolution)傅里叶变换(Fourier transform)拉普拉斯变换(Laplace transform)第2章连续时间系统的时域分析齐次解(homogeneous solution)特解(particular solution)特征方程(characteristic function)特征根(characteristic root)固有(自由)解(natural solution)强迫解(forced solution)起始条件(original condition)初始条件(initial condition)自由响应(natural response)强迫响应(forced response)零输入响应(zero-input response)零状态响应(zero-state response)冲激响应(impulse response)阶跃响应(step response)卷积积分(convolution integral)交换律(exchange law)分配律(distribute law)结合律(combine law)第3章傅里叶变换频谱(frequency spectrum)频域(frequency domain)三角形式的傅里叶级数(trigonomitric Fourier series)指数形式的傅里叶级数(exponential Fourier series)傅里叶系数(Fourier coefficient)直流分量(direct composition)基波分量(fundamental composition)n次谐波分量(nth harmonic component)复振幅(complex amplitude)频谱图(spectrum plot(diagram))幅度谱(amplitude spectrum)相位谱(phase spectrum)包络(envelop)离散性(discrete property)谐波性(harmonic property)收敛性(convergence property)奇谐函数(odd harmonic function)吉伯斯现象(Gibbs phenomenon)周期矩形脉冲信号(periodic rectangular pulse signal)周期锯齿脉冲信号(periodic sawtooth pulse signal)周期三角脉冲信号(periodic triangular pulse signal)周期半波余弦信号(periodic half–cosine signal)周期全波余弦信号(periodic full–cosine signal)傅里叶逆变换(inverse Fourier transform)频谱密度函数(spectrum density function)单边指数信号(single–sided exponential signal)双边指数信号(two–sided exponential signal)对称矩形脉冲信号(symmetry rectangular pulse signal)线性(linearity)对称性(symmetry)对偶性(duality)位移特性(shifting)时移特性(time–shifting)频移特性(frequency–shifting)调制定理(modulation theorem)调制(modulation)解调(demodulation)变频(frequency conversion)尺度变换特性(scaling)微分与积分特性(differentiation and integration)时域微分特性(differentiation in the time domain)时域积分特性(integration in the time domain)频域微分特性(differentiation in the frequency domain)频域积分特性(integration in the frequency domain)卷积定理(convolution theorem)时域卷积定理(convolution theorem in the time domain)频域卷积定理(convolution theorem in the frequency domain)取样信号(sampling signal)矩形脉冲取样(rectangular pulse sampling)自然取样(nature sampling)冲激取样(impulse sampling)理想取样(ideal sampling)取样定理(sampling theorem)调制信号(modulation signal)载波信号(carrier signal)已调制信号(modulated signal)模拟调制(analog modulation)数字调制(digital modulation)连续波调制(continuous wave modulation)脉冲调制(pulse modulation)幅度调制(amplitude modulation)频率调制(frequency modulation)相位调制(phase modulation)角度调制(angle modulation)频分多路复用(frequency–division multiplex(FDM))时分多路复用(time–division multiplex (TDM))相干(同步)解调(synchronous detection)本地载波(local carrier)系统函数(system function)网络函数(network function)频响特性(frequency response)幅频特性(amplitude frequency response)相频特性(phase frequency response)无失真传输(distortionless transmission)理想低通滤波器(ideal low–pass filter)截止频率(cutoff frequency)正弦积分(sine integral)上升时间(rise time)窗函数(window function)理想带通滤波器(ideal band–pass filter)第4章拉普拉斯变换代数方程(algebraic equation)双边拉普拉斯变换(two-sided Laplace transform)双边拉普拉斯逆变换(inverse two-sided Laplace transform)单边拉普拉斯变换(single-sided Laplace transform)拉普拉斯逆变换(inverse Laplace transform)收敛域(region of convergence(ROC))延时特性(time delay)s域平移特性(shifting in the s-domain)s域微分特性(differentiation in the s-domain)s域积分特性(integration in the s-domain)初值定理(initial-value theorem)终值定理(expiration-value)复频域卷积定理(convolution theorem in the complex frequency domain)部分分式展开法(partial fraction expansion)留数法(residue method)第5章策动点函数(driving function)转移函数(transfer function)极点(pole)零点(zero)零极点图(zero-pole plot)暂态响应(transient response)稳态响应(stable response)稳定系统(stable system)一阶系统(first order system)高通滤波网络(high-low filter)低通滤波网络(low-pass filter)二阶系统(second system)最小相移系统(minimum-phase system)维纳滤波器(Winner filter)卡尔曼滤波器(Kalman filter)低通(low-pass)高通(high-pass)带通(band-pass)带阻(band-stop)有源(active)无源(passive)模拟(analog)数字(digital)通带(pass-band)阻带(stop-band)佩利-维纳准则(Paley-Winner criterion)最佳逼近(optimum approximation)过渡带(transition-band)通带公差带(tolerance band)巴特沃兹滤波器(Butterworth filter)切比雪夫滤波器(Chebyshew filter)方框图(block diagram)信号流图(signal flow graph)节点(node)支路(branch)输入节点(source node)输出节点(sink node)混合节点(mix node)通路(path)开通路(open path)闭通路(close path)环路(loop)自环路(self-loop)环路增益(loop gain)不接触环路(disconnect loop)前向通路(forward path)前向通路增益(forward path gain)梅森公式(Mason formula)劳斯准则(Routh criterion)第6章数字系统(digital system)数字信号处理(digital signal processing)差分方程(difference equation)单位样值响应(unit sample response)卷积和(convolution sum)Z变换(Z transform)序列(sequence)样值(sample)单位样值信号(unit sample signal)单位阶跃序列(unit step sequence)矩形序列(rectangular sequence)单边实指数序列(single sided real exponential sequence)单边正弦序列(single sided exponential sequence)斜边序列(ramp sequence)复指数序列(complex exponential sequence)线性时不变离散系统(linear time-invariant discrete-time system)常系数线性差分方程(linear constant-coefficient difference equation)后向差分方程(backward difference equation)前向差分方程(forward difference equation)海诺塔(Tower of Hanoi)菲波纳西(Fibonacci)冲激函数串(impulse train)第7章数字滤波器(digital filter)单边Z变换(single-sided Z transform)双边Z变换(two-sided(bilateral)Z transform)幂级数(power series)收敛(convergence)有界序列(limitary-amplitude sequence)正项级数(positive series)有限长序列(limitary-duration sequence)右边序列(right-sided sequence)左边序列(left-sided sequence)双边序列(two-sided sequence)Z逆变换(inverse Z transform)围线积分法(contour integral method)幂级数展开法(power series expansion)z域微分(differentiation in the z-domain)序列指数加权(multiplication by an exponential sequence)z域卷积定理(z-domain convolution theorem)帕斯瓦尔定理(Parseval theorem)传输函数(transfer function)序列的傅里叶变换(discrete-time Fourier transform:DTFT)序列的傅里叶逆变换(inverse discrete-time Fourier transform:IDTFT)幅度响应(magnitude response)相位响应(phase response)量化(quantization)编码(coding)模数变换(A/D变换:analog-to-digital conversion)数模变换(D/A变换:digital-to- analog conversion)第8章端口分析法(port analysis)状态变量(state variable)无记忆系统(memoryless system)有记忆系统(memory system)矢量矩阵(vector-matrix)常量矩阵(constant matrix)输入矢量(input vector)输出矢量(output vector)直接法(direct method)间接法(indirect method)。
《信号与系统》专业术语中英文对照表第 1 章绪论信号(signal)系统(system)电压(voltage)电流(current)信息(information)电路(circuit)网络(network)确定性信号(determinate signal)随机信号(random signal)一维信号(one –dimensional signal)多维信号(multi–dimensional signal)连续时间信号(continuous time signal)离散时间信号(discrete time signal)取样信号(sampling signal)数字信号(digital signal)周期信号(periodic signal)非周期信号(nonperiodic(aperiodic)signal)能量(energy)功率(power)能量信号(energy signal)功率信号(power signal)平均功率(average power)平均能量(average energy)指数信号(exponential signal)时间常数(time constant)正弦信号(sine signal)余弦信号(cosine signal)振幅(amplitude)角频率(angular frequency)初相位(initial phase)周期(period)频率(frequency)欧拉公式(Euler’s formula)复指数信号(complex exponential signal)复频率(complex frequency)实部(real part)虚部(imaginary part)抽样函数Sa(t)(sampling(Sa)function)偶函数(even function)奇异函数(singularity function)奇异信号(singularity signal)单位斜变信号(unit ramp signal)斜率(slope)单位阶跃信号(unit step signal)符号函数(signum function)单位冲激信号(unit impulse signal)广义函数(generalized function)取样特性(sampling property)冲激偶信号(impulse doublet signal)奇函数(odd function)偶分量(even component)奇分量(odd component)正交函数(orthogonal function)正交函数集(set of orthogonal function)数学模型(mathematics model)电压源(voltage source)基尔霍夫电压定律(Kirchhoff’s voltage law(KVL))电流源(current source)连续时间系统(continuous time system)离散时间系统(discrete time system)微分方程(differential function)差分方程(difference function)线性系统(linear system)非线性系统(nonlinear system)时变系统(time–varying system)时不变系统(time–invariant system)集总参数系统(lumped–parameter system)分布参数系统(distributed–parameter system)偏微分方程(partial differential function)因果系统(causal system)非因果系统(noncausal system)因果信号(causal signal)叠加性(superposition property)均匀性(homogeneity)积分(integral)输入–输出描述法(input–output analysis)状态变量描述法(state variable analysis)单输入单输出系统(single–input and single–output system)状态方程(state equation)输出方程(output equation)多输入多输出系统(multi–input and multi–output system)时域分析法(time domain method)变换域分析法(transform domain method)卷积(convolution)傅里叶变换(Fourier transform)拉普拉斯变换(Laplace transform)第 2 章连续时间系统的时域分析齐次解(homogeneous solution)特解(particular solution)特征方程(characteristic function)特征根(characteristic root)固有(自由)解(natural solution)强迫解(forced solution)起始条件(original condition)初始条件(initial condition)自由响应(natural response)强迫响应(forced response)零输入响应(zero-input response)零状态响应(zero-state response)冲激响应(impulse response)阶跃响应(step response)卷积积分(convolution integral)交换律(exchange law)分配律(distribute law)结合律(combine law)第3 章傅里叶变换频谱(frequency spectrum)频域(frequency domain)三角形式的傅里叶级数(trigonomitric Fourier series)指数形式的傅里叶级数(exponential Fourier series)傅里叶系数(Fourier coefficient)直流分量(direct composition)基波分量(fundamental composition)n 次谐波分量(nth harmonic component)复振幅(complex amplitude)频谱图(spectrum plot(diagram))幅度谱(amplitude spectrum)相位谱(phase spectrum)包络(envelop)离散性(discrete property)谐波性(harmonic property)收敛性(convergence property)奇谐函数(odd harmonic function)吉伯斯现象(Gibbs phenomenon)周期矩形脉冲信号(periodic rectangular pulse signal)周期锯齿脉冲信号(periodic sawtooth pulse signal)周期三角脉冲信号(periodic triangular pulse signal)周期半波余弦信号(periodic half–cosine signal)周期全波余弦信号(periodic full–cosine signal)傅里叶逆变换(inverse Fourier transform)频谱密度函数(spectrum density function)单边指数信号(single–sided exponential signal)双边指数信号(two–sided exponential signal)对称矩形脉冲信号(symmetry rectangular pulse signal)线性(linearity)对称性(symmetry)对偶性(duality)位移特性(shifting)时移特性(time–shifting)频移特性(frequency–shifting)调制定理(modulation theorem)调制(modulation)解调(demodulation)变频(frequency conversion)尺度变换特性(scaling)微分与积分特性(differentiation and integration)时域微分特性(differentiation in the time domain)时域积分特性(integration in the time domain)频域微分特性(differentiation in the frequency domain)频域积分特性(integration in the frequency domain)卷积定理(convolution theorem)时域卷积定理(convolution theorem in the time domain)频域卷积定理(convolution theorem in the frequency domain)取样信号(sampling signal)矩形脉冲取样(rectangular pulse sampling)自然取样(nature sampling)冲激取样(impulse sampling)理想取样(ideal sampling)取样定理(sampling theorem)调制信号(modulation signal)载波信号(carrier signal)已调制信号(modulated signal)模拟调制(analog modulation)数字调制(digital modulation)连续波调制(continuous wave modulation)脉冲调制(pulse modulation)幅度调制(amplitude modulation)频率调制(frequency modulation)相位调制(phase modulation)角度调制(angle modulation)频分多路复用(frequency–division multiplex(FDM))时分多路复用(time –division multiplex(TDM))相干(同步)解调(synchronous detection)本地载波(local carrier)系统函数(system function)网络函数(network function)频响特性(frequency response)幅频特性(amplitude frequency response)相频特性(phase frequency response)无失真传输(distortionless transmission)理想低通滤波器(ideal low–pass filter)截止频率(cutoff frequency)正弦积分(sine integral)上升时间(rise time)窗函数(window function)理想带通滤波器(ideal band–pass filter)第 4 章拉普拉斯变换代数方程(algebraic equation)双边拉普拉斯变换(two-sided Laplace transform)双边拉普拉斯逆变换(inverse two-sided Laplace transform)单边拉普拉斯变换(single-sided Laplace transform)拉普拉斯逆变换(inverse Laplace transform)收敛域(region of convergence(ROC))延时特性(time delay)s 域平移特性(shifting in the s-domain)s 域微分特性(differentiation in the s-domain)s 域积分特性(integration in the s-domain)初值定理(initial-value theorem)终值定理(expiration-value)复频域卷积定理(convolution theorem in the complex frequency domain)部分分式展开法(partial fraction expansion)留数法(residue method)第 5 章策动点函数(driving function)转移函数(transfer function)极点(pole)零点(zero)零极点图(zero-pole plot)暂态响应(transient response)稳态响应(stable response)稳定系统(stable system)一阶系统(first order system)高通滤波网络(high-low filter)低通滤波网络(low-pass filter)二阶系统(second system)最小相移系统(minimum-phase system)维纳滤波器(Winner filter)卡尔曼滤波器(Kalman filter)低通(low-pass)高通(high-pass)带通(band-pass)带阻(band-stop)有源(active)无源(passive)模拟(analog)数字(digital)通带(pass-band)阻带(stop-band)佩利-维纳准则(Paley-Winner criterion)最佳逼近(optimum approximation)过渡带(transition-band)通带公差带(tolerance band)巴特沃兹滤波器(Butterworth filter)切比雪夫滤波器(Chebyshew filter)方框图(block diagram)信号流图(signal flow graph)节点(node)支路(branch)输入节点(source node)输出节点(sink node)混合节点(mix node)通路(path)开通路(open path)闭通路(close path)环路(loop)自环路(self-loop)环路增益(loop gain)不接触环路(disconnect loop)前向通路(forward path)前向通路增益(forward path gain)梅森公式(Mason formula)劳斯准则(Routh criterion)第 6 章数字系统(digital system)数字信号处理(digital signal processing)差分方程(difference equation)单位样值响应(unit sample response)卷积和(convolution sum)Z 变换(Z transform)序列(sequence)样值(sample)单位样值信号(unit sample signal)单位阶跃序列(unit step sequence)矩形序列(rectangular sequence)单边实指数序列(single sided real exponential sequence)单边正弦序列(single sided exponential sequence)斜边序列(ramp sequence)复指数序列(complex exponential sequence)线性时不变离散系统(linear time-invariant discrete-time system)常系数线性差分方程(linear constant-coefficient difference equation)后向差分方程(backward difference equation)前向差分方程(forward difference equation)海诺塔(Tower of Hanoi)菲波纳西(Fibonacci)冲激函数串(impulse train)第7 章数字滤波器(digital filter)单边Z 变换(single-sided Z transform)双边Z 变换(two-sided (bilateral) Z transform) 幂级数(power series)收敛(convergence)有界序列(limitary-amplitude sequence)正项级数(positive series)有限长序列(limitary-duration sequence)右边序列(right-sided sequence)左边序列(left-sided sequence)双边序列(two-sided sequence)Z 逆变换(inverse Z transform)围线积分法(contour integral method)幂级数展开法(power series expansion)z 域微分(differentiation in the z-domain)序列指数加权(multiplication by an exponential sequence)z 域卷积定理(z-domain convolution theorem)帕斯瓦尔定理(Parseval theorem)传输函数(transfer function)序列的傅里叶变换(discrete-time Fourier transform:DTFT)序列的傅里叶逆变换(inverse discrete-time Fourier transform:IDTFT)幅度响应(magnitude response)相位响应(phase response)量化(quantization)编码(coding)模数变换(A/D 变换:analog-to-digital conversion)数模变换(D/A 变换:digital-to- analog conversion)第8 章端口分析法(port analysis)状态变量(state variable)无记忆系统(memoryless system)有记忆系统(memory system)矢量矩阵(vector-matrix )常量矩阵(constant matrix )输入矢量(input vector)输出矢量(output vector)直接法(direct method)间接法(indirect method)状态转移矩阵(state transition matrix)系统函数矩阵(system function matrix)冲激响应矩阵(impulse response matrix)朱里准则(July criterion)。
• 信号的分类– 按信号载体的物理特性:电、光、声、磁、机械、热信号。
– 按自变量的数目:一维信号、多维信号(二维信号、三维信号等)。
• 按信号中自变量和幅度的取值特点:连续时间(continuous time, CT )信号:自变量时间在定义域内是连续的。
如果连续时间信号的幅度在一定的动态范围内也连续取值,信号就是模拟信号(analog signal )。
自然界中的信号大多数是模拟信号。
• 离散时间(discrete time, DT )信号:自变量时间在定义域内是离散的。
离散时间信号可以通过对连续时间信号的采样来获得,或信号本身就是离散时间信号。
• 数字信号(digital signal ):时间离散,幅度量化为有限字长二进制数的信号。
• 信号处理的根本目的:• 从信号中提取尽可能多的有用信息;增强信号的有用分量;估计信号的特征参数;识别信号的特性;抑制或消除不需要的甚至是有害的信号分量。
• 为达到上述目的,需要对信号进行分析和变换、扩展和压缩、滤波、参数估计、特性识别等加工,统称为信号处理。
• 信号处理• 具体正弦序列有以下三种情况:• (1) 2π/ ω0为整数:k=1,正弦序列是以2π/ ω0为周期的周期序列。
• (2) 2π/ ω0是有理数:设2π/ ω0 =P/Q ,式中P 、Q 是互为素数的整数,取k=Q,那么N=P ,则正弦序列是以P 为周期的周期序列 • (3) 2π/ ω0是无理数:任何整数k 都不能使N 为正整数,因此,此时的正弦序列不是周期序列。
• 线性系统y(n) = T [ax 1(n)+bx 2(n)]=ay 1(n)+by 2(n)• 线性时不变系统具有因果性的充分必要条件是系统的单位取样响应满h(n)=0, n<0 • 系统稳定的充分必要条件是系统的单位脉冲响应绝对可和 • ••• 序列的离散时间傅里叶变换的定义 • • ••• DTFT 的周期性• • 线性•• • 时移(位移)与频移• •• 序列乘以n (频域微分) •• 共轭序列 ()n h n ∞=-∞<∞∑)()()j j nn X ex n eωω∞-=-∞=∑1()()2j j nx n X eed πωωπωπ-=⎰(2)()(),j j M nn X ex n eωωπ∞-+=-∞=∑11221212()[()],()[()],[()()]()()j j j j X e DTFT x n X e DTFT x n DTFT ax n bx n aX e bX e ωωωω==+=+0000([()]()[()]()j n j j n j DTFT x n n e X e DTFT e x n X e ωωωωω---==ωωd edX jn nx DTFT j )()]([=)(*)](*[ωj e X n x DTFT -=)(*)](*[ωj e X n x DTFT =-• 序列分成实部与虚部两部分, 实部的DTFT 具有共轭对称性, 虚部乘j 一起对应的DTFT 具有共轭反对称性。
信号与系统郑君里复习要点一、引言信号与系统是电子信息科学与技术专业的核心学科之一,是掌握该领域知识的重要基础。
本文将对信号与系统中郑君里复习要点进行整理与总结,帮助广大学生更好地掌握这一学科。
二、信号的类型1. 连续时间信号(Continuous-time Signal):在连续时间上定义的信号,可用数学函数表示。
2. 离散时间信号(Discrete-time Signal):在离散时间上定义的信号,可用数列表示。
3. 连续幅度信号(Analog Signal):在幅度上连续变化的信号,可用模拟电路处理和传输。
4. 离散幅度信号(Digital Signal):在幅度上离散变化的信号,可用数字电路处理和传输。
三、系统的性质1. 因果性(Causality):系统的输出只依赖于当前和过去的输入。
2. 稳定性(Stability):当输入有界时,系统的输出也有界;当输入趋于无穷时,输出也趋于有界。
3. 线性性(Linearity):系统满足叠加原则,即输入的线性组合对应于输出的线性组合。
4. 时不变性(Time Invariance):系统的输入延时,输出也相应延时。
5. 可逆性(Invertibility):系统存在逆系统,即能恢复原输入信号。
四、连续时间信号与系统1. 连续时间傅里叶变换(Continuous-time Fourier Transform):用于将信号从时域转换到频域,获取信号的频率成分。
2. 系统的传输函数(Transfer Function):描述了输入信号和输出信号之间的关系,通过传输函数可计算系统的频率响应。
3. 连续时间卷积(Convolution):两个信号经过卷积运算得到新的信号。
卷积运算用于描述系统的输入和输出之间的关系。
五、离散时间信号与系统1. 离散时间傅里叶变换(Discrete-time Fourier Transform):类似于连续时间傅里叶变换,用于将离散时间信号从时域转换到频域。
数字信号处理Ch2.Discrete-TimeSignalsandSystemsCh2. Discrete-Time Signals andSystems22.1 Discrete-Time Signals -sequencesDiscrete-time signals are represented mathematically as sequences of numbers{[],}(2.1)x x n n =∈Z []=()()(2.2)a t nTa x n x t x nT ==()a x t{x [n ]} may be generated by periodically sampling a continuous-time signal z T : sampling periodzf s = 1/T: sampling frequencyx [n ] is referred to as the “n th sample”of the sequence 3 Graphical representation of a discrete-time signalNote : x [n ] is defined only for integer values of n . It is not correct to think of x [n ] as being zero for n is not an integer; x [n ] is simply undefined for non-integer values for n .4E.g. a speech signal and its sequence of samplesx (t )x [n ]From the sampling theorem , x (t ) can be reconstructed as accurately as desired from x [n ] if the samples are taken frequently enough. (chap 4)52.1.1 Basic Sequences and Sequence Operations0[][]y n x n n =?Basic sequence operationsSum of x [n ] and y [n ]Product of x [n ] and y [n ]Delay or shift of x [n ]:——sample-by-sample sum——sample-by-sample productα——multiplication of each sample value by multiplication of x [n ] by a number α6Basic Sequences[][][](2.6)k x n x k n k δ∞=?∞=∑1,0[]0,n n n δ=?=?≠? Unit sample sequence (impulse)An arbitrary sequence can be expressed as a sum of scaled, delayed unit impulses7Unit step sequence1,0[]0,0n u n n ≥?=?8Rectangular sequence1,01[]0,0,N n N R n n n N≤≤??=?<≥?从n =0开始到n =N -1,共有N 个幅度为1的数值,其余点上均为09以上三个序列之间的关系[][][1](2.10)n u n u n δ=??0[][](2.9)k u n n k b δ∞==?∑[][][]N R n u n u n N =??10Complex exponential sequence0()00[]cos()sin()j n x n Ae A n jA n ωφωφωφ+==+++ω0 : digital frequency (数字域频率): phase (radians)φ0[]cos()x n A n ωφ=+z特例:Sinusoidal sequence0[]sin()x n A n ωφ=+A : magnitude11Complex exponential sequence zOnly consider frequencies in an interval of 2π0(2)r ωπ+——Complex exponential sequences with frequencies , are indistinguishable from each another.z2π模糊0(2)[]j r nx n Aer Zωπ+=∈0j nAe ω=02j n j rnAe e ωπ=or 02πωπωπ<≤≤<=1122.1.2 Periodicity of sequence定义:如果对于所有的n , 存在一个最小的正整数N ,使x [n ] = x [n + N ]则称x [n ]是周期序列,且周期为N 。
信号与系统第⼆版刘树棠课后答案信号与系统刘树棠;课后习题答案美国⿇省理⼯学院(MIT)的经典教材之⼀,讨论了信号与系统分析的基本理论、基本分析⽅法及其应⽤。
本书是美国⿇省理⼯学院(MIT)的经典教材之⼀,讨论了信号与系统分析的基本理论、基本分析⽅法及其应⽤。
全书共分11章,主要讲述了线性系统的基本理论、信号与系统的基本概念、线性时扫⼀扫⽂末在⾥⾯回复答案+信号与系统⽴即得到答案不变系统、连续与离散信号的傅⾥叶表⽰、傅⾥叶变换以及时域和频域系统的分析⽅法等内容。
本书作者使⽤了⼤量在滤波、采样、通信和反馈系统中的实例,并⾏讨论了连续系统、离散系统、时域系统和频域系统的分析⽅法,使读者能透彻地理解各种信号系统的分析⽅法并⽐较其异同。
Alan V. Oppenheim,美国⿇省理⼯学院(MIT)电⽓与计算机科学系Ford教授,MIT电⼦学研究实验室(RLE)⾸席研究员,美国国家⼯程院院⼠,IEEE会⼠,研究兴趣为通⽤领域的信号处理及应⽤,曾因出⾊的科研和教学⼯作多次获奖。
另著有Discrete-Time Signal Processing。
<BR>美国⿇省理⼯学院(MIT)电⽓与计算机科学系Ford教授,MIT电⼦学研究实验室(RLE)⾸席研究员,美国国家⼯程院院⼠,IEEE会⼠,研究兴趣为通⽤领域的信号处理及应⽤,曾因出⾊的科研和教学⼯作多次获奖。
另著有Discrete-Time Signal Processing。
第1章信号与系统1.0 引⾔1.1 连续时间信号和离散时间信号1.1. 1 举例与数学表⽰2.1. 2 信号能量与功率1.2 ⾃变量的变换3.2. 1 ⾃变量变换举例4.2. 2 周期信号5.2. 3信号与系统课后答案刘树棠;偶信号与奇信号1.3 指数信号与正弦信号6.3. 1 连续时间复指数信号与正弦信号7.3. 2 离散时间复指数信号与正弦信号8.3. 3 离散时间复指数序列的周期性质1.4 单位冲激函数与单位阶跃函数显⽰全部信息译者序Signals and Systems(A. V. Oppenheim, A. S. Willsky)⼀书1983年在美国公开出版发⾏,当年8⽉即由笔者从美国带回中国。