clear?all;
clc;
cycl?=?100;
snr_db?=?0:1:10;
%?輸入信息
msg?=?randint（11024）;
ber0?=?zeros（cycllength（snr_db））;
ber1?=?zeros（cycllength（snr_db））;
%?Trellises
trel?=?poly2trellis（3[6?7]）;?%Define?trellis?for?rate?1/2?code.
for?n?=?1:cycl
????for?x?=?1:length（snr_db）
????????%?Code?words
????????code?=?convenc（msgtrel）;?%?Encode.
????????%?Interleaver
????????state?=?20;
????????inter?=?randintrlv（codestate）;
????????%?BPSK?調制
????????s0?=?sign（msg?-?0.5）;?
????????s1?=?sign（inter-0.5）;?
????????s2?=?sign（code-0.5）;
????????%?AWGN?Channel
????????add_noise0=awgn（s0snr_db（x）‘measured‘）;
????????add_noise1=awgn（s1snr_db（x）‘measured‘）;
????????add_noise2=awgn（s2snr_db（x）‘measured‘）;

????????%?解調
????????r_0?=?0.5*sign（add_noise0）?+?0.5;
????????r_1?=?0.5*sign（add_noise1）?+?0.5;?
????????r_2?=?0.5*sign（add_noise2）?+?0.5;?
????????%?Deinterleaver
????????deinter_1?=?randdeintrlv（r_1state）;
????????%?Traceback?length
????????tblen?=?5;
????????%?vitdec
????????decoded1?=?vitdec（deinter_1treltblen‘cont‘‘hard‘）;

????????%?比較誤碼率
????????[num0rat0]?=?biterr（r_0msg）;
????????[num1rat1]?=?biterr（double（decoded1（tblen+1:end））msg（1:end-tblen））;
????????ber0（nx）?=?rat0;
????????ber1（nx）?=?rat1;
????end
end?
ber0?=?mean（ber0）;
ber1?=?mean（ber1）;
figure;
semilogy（snr_dbber0‘b-o‘snr_dbber1‘r-s‘）;
xlabel（‘SNR?（dB）‘）;
ylabel（‘BER‘）;
legend（‘未使用編碼‘‘使用卷積編碼‘）;
title（‘碼率為1/2時的卷積碼性能分析‘）;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????1499??2016-04-25?14:32??main432.m
?????文件????????2696??2016-04-25?14:35??main433.m
?????文件????????2622??2016-04-25?14:34??main434.m
?????文件????????2119??2016-04-25?14:39??main435.m
?????文件????????1498??2016-04-06?17:54??main444.m
?????文件????????2697??2016-04-06?17:55??main445.m
?????文件????????2623??2016-04-06?16:24??main446.m
?????文件????????2120??2016-04-06?16:58??main447.m
?????文件????????1919??2016-04-06?17:48??main448.m