uwbawgnchan.m

来自「斯坦福大学scholze教授实验室uwb信道建模程序的源代码」· M 代码 · 共 59 行

function [sys,x0,str,ts] = AWGNchan(t,x,u,flag,noisePower)

switch flag,

  %%%%%%%%%%%%%%%%%%
  % Initialization %
  %%%%%%%%%%%%%%%%%%
  case 0,
    sizes = simsizes;

    sizes.NumContStates  = 0;
    sizes.NumDiscStates  = 0;
    sizes.NumOutputs     = 1;
    sizes.NumInputs      = 1;
    sizes.DirFeedthrough = 1;
    sizes.NumSampleTimes = 1;   % at least one sample time is needed

    sys = simsizes(sizes);
    
    x0  = [];
    str = []; ts  = [0 0];

  %%%%%%%%%%%%%%%
  % Derivatives %
  %%%%%%%%%%%%%%%
  case 1,
    sys=[];

  %%%%%%%%%%
  % Update %
  %%%%%%%%%%
  case 2,
      sys=[];
      
  %%%%%%%%%%%
  % Outputs %
  %%%%%%%%%%%
  case 3,
      noiseVariance=1e-3*10^(noisePower/10);
      sys=u+sqrt(noiseVariance)*randn(1);

  %%%%%%%%%%%%%%%%%%%%%%%
  % GetTimeOfNextVarHit %
  %%%%%%%%%%%%%%%%%%%%%%%
  case 4,
    sys=[];
  %%%%%%%%%%%%%
  % Terminate %
  %%%%%%%%%%%%%
  case 9,
     sys=[];
     
  %%%%%%%%%%%%%%%%%%%%
  % Unexpected flags %
  %%%%%%%%%%%%%%%%%%%%
  otherwise
    error(['Unhandled flag = ',num2str(flag)]);

end