%本程序為LTE系統中咬尾卷積碼的住址主程序，程序包括隨機比特序列的生成，tailbiting卷積
%編碼，QPSK調制映射，AWGN噪聲添加，QPSK軟解調，TSVA譯碼算法，誤碼率及誤塊率統計。
%LTE中卷積碼碼率為1/3，仿真中需要設置信息位長度，信噪比和仿真塊數。
clear;
clc;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Info_length?=?40;?%?信息位長度
Eb_N0?=?0:1:5;?%dB??比特信噪比（start?:?step?:?end）
sim_code_blk_num?=?10000;?%每個信噪比點仿真的碼塊數。
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Code_length?=?Info_length*3;?%?code?length?rate=1/3
SNR?=?Eb_N0+10*log10（2/3）;?%?snr?for?qpsk?rate?1/3
disp（‘LTE?tailbiting?convolutional?code?simulation‘）;
disp（‘Decoding?algorithm:?TSVA‘）;
disp（‘Modulation:?QPSK?Code?rate:?1/3?Channel:?AWGN‘）;
for?snr_idx?=?1:length（SNR）
????total_bit_err_num?=?0;
????blk_err_num?=?0;
????code_bit_err_num?=?0;
????for?code_blk_cnt?=?1:sim_code_blk_num
????????info?=?randi（[01]Info_length1）;%低版本matlab如無此函數可用?info?=?randint（Info_length1）;???????
????????%咬尾卷積編碼
????????tbcc_code?=?lte_tbcc_enc（info）;????????
????????%QPSK調制
????????tbcc_symb?=?complex（1-2*tbcc_code（1:2:end）1-2*tbcc_code（2:2:end））/sqrt（2）;????????
????????%AWGN信道
????????tbcc_symb?=?awgn（tbcc_symbSNR（snr_idx））;????????
????????%QPSK軟解調
????????code_soft?=?reshape（[real（tbcc_symb）imag（tbcc_symb）].‘[]1）;??????
????????%TSVA譯碼
????????dec_bit?=?lte_tbcc_dec（code_soft）;
????????%對接收碼字硬判決
????????code_hard_slice?=?double（code_soft<0）;
????????%錯誤數統計
????????bit_err_num?=?numel（find（info~=dec_bit））;
????????total_bit_err_num?=?total_bit_err_num+bit_err_num;
????????code_bit_err_num?=?code_bit_err_num+numel（find（tbcc_code~=code_hard_slice））;
????????blk_err_num?=?blk_err_num+double（bit_err_num>0）;
????end
????%berbler統計
????ber（snr_idx）?=?total_bit_err_num/（sim_code_blk_num*Info_length）;
????hard_slice_ber（snr_idx）?=?code_bit_err_num/（sim_code_blk_num*Code_length）;
????bler（snr_idx）?=?blk_err_num/sim_code_blk_num;
????disp（[‘Eb/N0=‘num2str（Eb_N0（snr_idx）‘%.2f‘）‘dB???SNR=‘num2str（SNR（snr_idx）‘%.2f‘）‘dB???BER=‘num2str（ber（snr_idx）‘%e‘）...
?????????‘???BLER=‘num2str（bler（snr_idx）‘%e‘）]）;
????if（ber（snr_idx）<1e-5）
????????break;
????end
end
%figure
figure;semilogy（Eb_N0（1:snr_idx）ber（1:snr_idx）‘o-‘Eb_N0（1:snr_idx）bler（1:snr_idx）‘*-‘）;grid?on;
legend（‘BER‘‘BLER‘）;xlabel（‘Eb/N0（dB）‘）;
figure;semilogy（SNR（1:snr_idx）ber（1:snr_idx）‘o-‘SNR（1:snr_idx）hard_slice_ber（1:snr_idx）‘*-‘）;grid?on;
legend（‘BER‘‘Uncoded-BER‘）;xlabel（‘SNR（dB）‘）;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????2630??2014-04-03?21:42??LTE_tailbiting_cc_sim.m
?????文件????????4099??2014-03-30?21:31??lte_tbcc_dec.m
?????文件?????????570??2014-03-30?18:08??lte_tbcc_enc.m
?????目錄???????????0??2014-03-27?22:20??參考文章\
?????文件??????331060??2014-03-27?22:03??參考文章\Improved?sova-based?decoding?algorithm?for?tailbiting?codes?on?wireless?channels.pdf
?????文件?????7815075??2014-03-27?21:14??參考文章\LTE信道糾錯碼原理與實現_連立杰.caj
?????文件??????560189??2014-03-27?21:11??參考文章\LTE系統中咬尾卷積碼的編譯碼算法仿真及性能分析_陳發堂.pdf