实验一 熟悉MATLAB环境 常用离散时间信号的仿真
[实验内容] 1．用MATLAB实现函数impseq(n0,n1,n2)，使函数实现 δ(n-n0)。 该函数的格式为： Function [x,n]=impseq(n0,n1,n2) % Generate x(n)=delta(n-n0);n1<=n<=n2 % [x,n]=impseq(n0,n1,n2) 2．用MATLAB实现函数stepseq(n0,n1,n2)，使函数实现u(n-n0)， 。 function [x,n]=stepseq(n0,n1,n2) %Generate x(n)=u(n-n0);n1<=n<=n2 %[x,n]=stepseq(n0,n1,n2) 3. 用MATLAB实现常见的离散时间序列。
1.单位脉冲序列 Unit sample sequence Representation in MATLAB
Function [x,n]=impseq(n0,n1,n2) A: n=[n1:n2]; x = zeros(1,n2-n1+1); x(n0-n1+1)=1; B: n=[n1:n2]; x = [(n-n0)==0]; stem(n,x,’ro’);
2. 单位阶跃序列 Unit step sequence A: n=[n1:n2]; x=zeros(1,n2-n1+1); x(n0-n1+1:end)=1; B: n=[n1:n2]; x=[(n-n0)>=0];
3. 实指数序列 For Example: n=[0:10]; x=(0.9).^n; stem(n,x,’ro’)
4. 复指数序列 Attenuation: 衰减因子 frequency in radians: For Example: n=[0:10]; x=exp((2+3j)*n);
5. 正弦序列 Phase in radians For Example: n=[0:10]; x=3*cos(0.1*pi*n+pi/3)+2*sin(0.5*pi*n)
6. 随机序列 Rand(1,N) Generate a length N random sequence whose elements are uniformly distributed between [0,1] Randn(1,N) Generate a length N Gaussian random sequence with mean 0 and variance 1. en [0,1]
7. 周期序列 A sequence x(n) is periodic if x(n)=x(n+N) The smallest integer N is called the fundamental period For example A: xtilde=[x,x,x,…x] B: xtilde=x’*ones(1,P); xtilde=xtilde(:); xtilde=xtilde’; transposition