LS_CE.m

function H_LS = LS_CE(Y,Xp,pilot_loc,Nfft,Nps,int_opt)
% LS channel estimation function
% Inputs:
%       Y         = Frequency-domain received signal
%       Xp        = Pilot signal
%       pilot_loc = Pilot location
%       N         = FFT size
%       Nps       = Pilot spacing
%       int_opt   = 'linear' or 'spline'
% output:
%       H_LS      = LS channel etimate

%MIMO-OFDM Wireless Communications with MATLAB¢ç   Yong Soo Cho, Jaekwon Kim, Won Young Yang and Chung G. Kang
%2010 John Wiley & Sons (Asia) Pte Ltd

Np=Nfft/Nps; k=1:Np; LS_est(k) = Y(pilot_loc(k))./Xp(k);  % LS channel estimation
if  lower(int_opt(1))=='l', method='linear'; else method='spline';  end
H_LS = interpolate(LS_est,pilot_loc,Nfft,method); % Linear/Spline interpolation