《DSP using MATLAB》示例Example 8.1

代码: % Discrete-time Signal x1(n) % Ts = 0.0002; n = -25:1:25; nTs = n*Ts; Fs = 1/Ts; x = exp(-1000*abs(nTs)); Ts = 0.001; n = -5:1:5; nTs = n*Ts; Fs = 1/Ts; x = exp(-1000*abs(nTs)); % Analog Signal Dt = 0.00005; t = -0.005:Dt:0.005; xa = x * sinc(Fs*

代码: % Analog Signal Dt = 0.00005; t = -0.005:Dt:0.005; xa = exp(-1000*abs(t)); % Continuous-time Fourier Transform Wmax = 2*pi*2000; K = 500; k = 0:1:K; % index array k for frequencies W = k*Wmax/K; % freqency between 0 and +pi, [0,pi] axis divided i

代码: % Analog Signal Dt = 0.00005; t = -0.005:Dt:0.005; xa = exp(-1000*abs(t)); % Discrete-time Signal Ts = 0.0002; n = -25:1:25; x = exp(-1000*abs(n*Ts)); % Discrete-time Fourier Transform %Wmax = 2*pi*2000; K = 500; k = 0:1:K; w = pi*k/K; % index ar

上代码: subplot(1,1,1); b = 1; a = [1, -0.8]; n = [0:100]; x = cos(0.05*pi*n); y = filter(b,a,x); figure('NumberTitle', 'off', 'Name', 'Input and Output sequence'); set(gcf,'Color','white'); subplot(2,1,1); stem(n,x); title('Input sequence'); xlabel('n'

上代码 % noise sequence 1 x = [3, 11, 7, 0, -1, 4, 2]; nx = [-3:3]; % given signal x(n) [y,ny] = sigshift(x,nx,2); % obtain x(n-2) set(gcf,'Color','white') subplot(2,1,1);stem(nx,x); title('sequence x(n)'); xlabel('n');ylabel('x(n)'); grid on subplot(2,

代码: n = [-5:5]; x = (-0.9).^n; % x(n) = k = -200:200; w = (pi/100)*k; % [0,pi] axis divided into 101 points. X = x * (exp(-j*pi/100)) .^ (n'*k); magX = abs(X); angX = angle(X); realX = real(X); imagX = imag(X); set(gcf,'Color','white'); subplot(2,2,1

代码: b = [1]; a = [1, -0.9]; n = [-5:50]; h = impz(b,a,n); set(gcf,'Color','white'); %subplot(2,1,1); stem(n,h); title('Impulse Response'); xlabel('n'); ylabel('h(n)'); grid on; x = stepseq(0, -5, 50) - stepseq(10, -5, 50) y = filter(b, a, x); figure;

n = [0:10]; x = stepseq(0,0,10) - stepseq(10,0,10); [xe,xo,m] = evenodd(x,n); set(gcf,'Color',[1,1,1]) % 改变坐标外围背景颜色 stem(n,x); title('Rectangular Pulse'); xlabel('n'); ylabel('x(n)') ; axis([-10,10,0,1.2]) grid on figure set(gcf,'Color',[1,1,1]) stem

用到的性质 上代码: n = 0:100; x = cos(pi*n/2); k = -100:100; w = (pi/100)*k; % freqency between -pi and +pi , [0,pi] axis divided into 101 points. X = x * (exp(-j*pi/100)) .^ (n'*k); % DTFT of x % signal multiplied y = exp(j*pi*n/4) .* x; % signal multiplied