VLC-OFDM-Simulation-original

%OFDM Simulation in MATLAB %The intial code is from Jordan Street's work. close all; clc clear all; %% Simulation Parameters %Moduluation method: BPSK, QPSK, 8PSK, 16QAM, 32QAM, 64QAM, %Assume we use 14 channels of 256. 1,2 and 3 we use 128QAM, 4 and 5 we use 64QAM, 6,7,8 we use 32QAM mod_methods = {'BPSK', 'QPSK', '8QAM', '16QAM', '32QAM', '64QAM','128QAM','256QAM'}; %Channel Information we use Sub_channel_num_used = 80; Channel_bit = [10,10,10,10,10,10,10,10];%Channel number of each modulation scheme Total_bit_num_in_one_ofdm_symbol = 8*Channel_bit(8) + 7*Channel_bit(7) + 6*Channel_bit(6) + 5*Channel_bit(5) + 4*Channel_bit(4) + 3*Channel_bit(3) + 2*Channel_bit(2) + 1*Channel_bit(1); %fft size nfft = 512; %size of cycle prefix extension n_cpe = 16; %Channel estimation method ch_est_method = 'LS'; %ch_est_method = 'none'; %SNR in dB snr = 10;%The unit is Db, the ratio of average power of signal and noise %Number of channel taps n_taps = 8;%this is the same as the example, I think it is the pulse response %Check whether the parameter is right or not? if Sub_channel_num_used ~= sum(Channel_bit) disp('error: The summary of bit allocated channel is not equal to total used channel'); exit; end if Sub_channel_num_used >= nfft/2 - 1%dc cannot be used in the simulation disp('error: The number of used subchannel is larger than fft number'); exit; end %%Read the image and convert to binary format, we use one picture as our signal source im = imread('baboon.png'); im_bin_1 = im(:); im_bin_2 = dec2bin(im_bin_1,8)'; im_bin = im_bin_2(:); %transfer the matrix to bit sequence %% Transmisstor %Binary Stream to Symbol %We assume we just use 20 subchannel, the first five we use first five channel as %Step 1: Padding source signal sys_rem = mod(Total_bit_num_in_one_ofdm_symbol-mod(length(im_bin),Total_bit_num_in_one_ofdm_symbol),Total_bit_num_in_one_ofdm_symbol);%calculate the bit not enought for one OFDM frame padding = repmat('0',sys_rem,1); im_bin_padded = [im_bin; padding];%combining in row ofdm_symbol_total_num = length(im_bin_padded)/Total_bit_num_in_one_ofdm_symbol; cons_data = reshape(im_bin_padded,Total_bit_num_in_one_ofdm_symbol,ofdm_symbol_total_num); %Mapping source bit to symbol %Step 2: Devide the signal source into different groups according modulation scheme, offline processing method cons_data_1bit = cons_data(1:1*Channel_bit(1),:); cons_data_2bit = cons_data(1*Channel_bit(1)+1:1*Channel_bit(1)+2*Channel_bit(2),:); cons_data_3bit = cons_data(1*Channel_bit(1)+2*Channel_bit(2)+1:1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3),:); cons_data_4bit = cons_data(1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+1:1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4),:); cons_data_5bit = cons_data(1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+1:1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+5*Channel_bit(5),:); cons_data_6bit = cons_data(1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+5*Channel_bit(5)+1:1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+5*Channel_bit(5)+6*Channel_bit(6),:); cons_data_7bit = cons_data(1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+5*Channel_bit(5)+6*Channel_bit(6)+1:1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+5*Channel_bit(5)+6*Channel_bit(6)+7*Channel_bit(7),:); cons_data_8bit = cons_data(1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+5*Channel_bit(5)+6*Channel_bit(6)+7*Channel_bit(7)+1:1*Channel_bit(1)+2*Channel_bit(2)+3*Channel_bit(3)+4*Channel_bit(4)+5*Channel_bit(5)+6*Channel_bit(6)+7*Channel_bit(7)+8*Channel_bit(8),:); %Step 3: reshaping the each group for symbol mapping, and do the tranposition operation for mapping cons_data_1bit_reshape = reshape(cons_data_1bit,1,ofdm_symbol_total_num*Channel_bit(1))'; cons_data_2bit_reshape = reshape(cons_data_2bit,2,ofdm_symbol_total_num*Channel_bit(2))'; cons_data_3bit_reshape = reshape(cons_data_3bit,3,ofdm_symbol_total_num*Channel_bit(3))'; cons_data_4bit_reshape = reshape(cons_data_4bit,4,ofdm_symbol_total_num*Channel_bit(4))'; cons_data_5bit_reshape = reshape(cons_data_5bit,5,ofdm_symbol_total_num*Channel_bit(5))'; cons_data_6bit_reshape = reshape(cons_data_6bit,6,ofdm_symbol_total_num*Channel_bit(6))'; cons_data_7bit_reshape = reshape(cons_data_7bit,7,ofdm_symbol_total_num*Channel_bit(7))'; cons_data_8bit_reshape = reshape(cons_data_8bit,8,ofdm_symbol_total_num*Channel_bit(8))'; %Step 4: transform from bit to dec for symbol mapping cons_data_1bit_sys_id = bin2dec(cons_data_1bit_reshape); cons_data_2bit_sys_id = bin2dec(cons_data_2bit_reshape); cons_data_3bit_sys_id = bin2dec(cons_data_3bit_reshape); cons_data_4bit_sys_id = bin2dec(cons_data_4bit_reshape); cons_data_5bit_sys_id = bin2dec(cons_data_5bit_reshape); cons_data_6bit_sys_id = bin2dec(cons_data_6bit_reshape); cons_data_7bit_sys_id = bin2dec(cons_data_7bit_reshape); cons_data_8bit_sys_id = bin2dec(cons_data_8bit_reshape); %Adding this step to calculate the symbol error rate in each subchannel cons_data_1bit_sys_id_reshape = reshape(cons_data_1bit_sys_id,Channel_bit(1),ofdm_symbol_total_num); cons_data_2bit_sys_id_reshape = reshape(cons_data_2bit_sys_id,Channel_bit(2),ofdm_symbol_total_num); cons_data_3bit_sys_id_reshape = reshape(cons_data_3bit_sys_id,Channel_bit(3),ofdm_symbol_total_num); cons_data_4bit_sys_id_reshape = reshape(cons_data_4bit_sys_id,Channel_bit(4),ofdm_symbol_total_num); cons_data_5bit_sys_id_reshape = reshape(cons_data_5bit_sys_id,Channel_bit(5),ofdm_symbol_total_num); cons_data_6bit_sys_id_reshape = reshape(cons_data_6bit_sys_id,Channel_bit(6),ofdm_symbol_total_num); cons_data_7bit_sys_id_reshape = reshape(cons_data_7bit_sys_id,Channel_bit(7),ofdm_symbol_total_num); cons_data_8bit_sys_id_reshape = reshape(cons_data_8bit_sys_id,Channel_bit(8),ofdm_symbol_total_num); %Step 4: Mapping and judging whether the matrix is empty or not not_empty_flag = zeros(8,1); if Channel_bit(1)~=0 cons_data_1bit_symbol = qammod(cons_data_1bit_sys_id,2^1,'UnitAveragePower',true); cons_data_1bit_symbol_reshape = reshape(cons_data_1bit_symbol,Channel_bit(1),ofdm_symbol_total_num); not_empty_flag(1) = 1; else cons_data_1bit_symbol_reshape = []; end if Channel_bit(2)~=0 cons_data_2bit_symbol = qammod(cons_data_2bit_sys_id,2^2,'UnitAveragePower',true); cons_data_2bit_symbol_reshape = reshape(cons_data_2bit_symbol,Channel_bit(2),ofdm_symbol_total_num); not_empty_flag(2) = 1; else cons_data_2bit_symbol_reshape = []; end if Channel_bit(3)~=0 cons_data_3bit_symbol = qammod(cons_data_3bit_sys_id,2^3,'UnitAveragePower',true); cons_data_3bit_symbol_reshape = reshape(cons_data_3bit_symbol,Channel_bit(3),ofdm_symbol_total_num); not_empty_flag(3) = 1; else cons_data_3bit_symbol_reshape = []; end if Channel_bit(4)~=0 cons_data_4bit_symbol = qammod(cons_data_4bit_sys_id,2^4,'UnitAveragePower',true); cons_data_4bit_symbol_reshape = reshape(cons_data_4bit_symbol,Channel_bit(4),ofdm_symbol_total_num); not_empty_flag(4) = 1; else cons_data_4bit_symbol_reshape = []; end if Channel_bit(5)~=0 cons_data_5bit_symbol = qammod(cons_data_5bit_sys_id,2^5,'UnitAveragePower',true); cons_data_5bit_symbol_reshape = reshape(cons_data_5bit_symbol,Channel_bit(5),ofdm_symbol_total_num); not_empty_flag(5) = 1; else cons_data_5bit_symbol_reshape = []; end if Channel_bit(6)~=0 cons_data_6bit_symbol = qammod(cons_data_6bit_sys_id,2^6,'UnitAveragePower',true); cons_data_6bit_symbol_reshape = reshape(cons_data_6bit_symbol,Channel_bit(6),ofdm_symbol_total_num); not_empty_flag(6) = 1; else cons_data_6bit_symbol_reshape = []; end if Channel_bit(7)~=0 cons_data_7bit_symbol = qammod(cons_data_7bit_sys_id,2^7,'UnitAveragePower',true); cons_data_7bit_symbol_reshape = reshape(cons_data_7bit_symbol,Channel_bit(7),ofdm_symbol_total_num); not_empty_flag(7) = 1; else cons_data_7bit_symbol_reshape = []; end if Channel_bit(8)~=0 cons_data_8bit_symbol = qammod(cons_data_8