prefix.m

一些关于调指和解调的小程序

function out=prefix(input,L)

%%% This function copy the last L points of inputed sequence to the head of this sequence
%%% input---Inputed sequence, and is parallel sequence
%%% L--- The length of cyclic prefix, or the number of cyclic prefix points

K=length(input);

p_out=[input(K-L+1:K)
       input];
 
out=p_out;         %%% The output is also parallel sequence