91av视频/亚洲h视频/操亚洲美女/外国一级黄色毛片 - 国产三级三级三级三级

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    文件類型: .zip
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    發(fā)布日期: 2021-06-04
  • 語言: 其他
  • 標簽: PSK;ASK;QAM??

資源簡介

包含2ASK、4ASK、8ASK等不同MASK調(diào)制方式下抗噪聲性能對比和抗多徑對比,單路多徑、二路多徑、三路多徑,即銳利信道下性能; 包含2PSK、4PSK、8PSK等不同MPSK調(diào)制方式下抗噪聲性能對比和抗多徑對比,單路多徑、二路多徑、三路多徑,即銳利信道下性能; 包含16QAM、64QAM、128QAM等不同MQAM調(diào)制方式下抗噪聲性能對比和抗多徑對比,單路多徑、二路多徑、三路多徑,即銳利信道下性能; 包含OFDM-QPSK OFDM-QAM等不同OFDM調(diào)制方式下抗噪聲性能對比和抗多徑對比,單路多徑、二路多徑、三路多徑,即銳利信道下性能;

資源截圖

代碼片段和文件信息

close?all;
clear?all;
clc;
t0=0.049999;???%總仿真時間,單位為s
%?0.004999?50個碼元?0.049999?500個碼元??0.099999?1000個碼元
%?碼元寬度?0.0001s,?每個碼元100個采樣點
ts=1*10^-6;??%采樣間隔1us
fc=50*10^3;????%載波頻率50kHz
?snr=6;?%信噪比,以dB來表示
fs=1/ts;??%采樣頻率?1M
df=0.3;??%頻率分辨率
t=[0:ts:t0];
%計算仿真的數(shù)字序列長度
n=size(t);
N=n(2)/100;?%?碼元個數(shù)

%載波信號生成,頻率為fc
c=cos(2*pi*fc*t);
%本地載波信號
c_local=cos(2*pi*fc.*t);


m2=fix(2*rand(1N));?%生成消息信號(二進制數(shù)字序列)

%將二進制數(shù)字序列轉(zhuǎn)換為時域信號,也就是對數(shù)字符號進行采樣處理
for?k=1:N
????for?i=(100*k-99):(100*k)
?????????m2_time(i)=m2(k);
????end???
end

%清零處理
for?i=(100*(N/2)+1):(100*N)
????m2_time(i)=0;
end


ask2=m2_time.*c;?%生成2ASK時域信號
%
figure(1)????
subplot(311)??????%子圖語句
plot(tm2_time)?????%畫出調(diào)制信號
axis([0?0.001?-0.5?3.5])
title(‘調(diào)制信號‘);
grid?on;

subplot(312)
plot(tc)??????????%畫出載波信號
axis([0?0.001?-3.5?3.5])
title(‘載波信號‘);
grid?on;

subplot(313)
plot(task2)??????%畫出已調(diào)信號
axis([0?0.001?-3.5?3.5])
title(‘ASK已調(diào)信號‘);
grid?on;
%}


ask2_noise=awgn(ask2snr‘measured‘);??%經(jīng)過AWGN高斯白噪聲

%繪制ASK信號波形(受噪聲影響)
figure(2)
plot(task2_noise)
grid?on;
title(‘a(chǎn)sk信號波形(加噪)‘)

axis([0?0.001?-2?2])
%本地載波與接收已調(diào)信號相乘,實現(xiàn)相干解調(diào)
ask2_dem1=ask2_noise.*c_local;

%將相乘結(jié)果轉(zhuǎn)換為頻域
[ASK2_DEM1ask2_dem1df1]=fftseq(ask2_dem1tsdf);?%df1是頻率采樣間隔
ASK2_DEM1=ASK2_DEM1/fs;?%乘以FFT系數(shù)
f=[0:df1:df1*(length(ask2_dem1)-1)]-fs/2;?%f是FFT變換后的頻域點
%
%將已調(diào)信號轉(zhuǎn)換為頻域
[ASK2_NOISEask2_noisedf1]=fftseq(ask2_noisetsdf);
ASK2_NOISE=ASK2_NOISE/fs;
%}
%低通濾波器設(shè)計
f_cutoff=50000;??????????%截止頻率
n_cutoff=floor(f_cutoff/df1);?%頻率采樣個數(shù)
H=zeros(size(f));?????????%H是頻域低通濾波器
H(1:n_cutoff)=2*ones(1n_cutoff);
H(length(f)-n_cutoff+1:length(f))=2*ones(1n_cutoff);?%H的前n_cutoff個和后n_cutoff個值設(shè)為2,其他值為0

%接收信號通過低通濾波器
ASK2_DEM2=H.*ASK2_DEM1;
ask2_dem2=real(ifft(ASK2_DEM2))*fs;?%重新轉(zhuǎn)化為時域信號


figure(3)
%subplot(313)
plot(fabs(fftshift(ASK2_NOISE)))???%畫出已調(diào)信號頻率
axis([-150000?150000?0?0.001])
xlabel(‘頻率‘);
title(‘已調(diào)信號頻譜‘);
grid?on;
%}

%抽樣判決
k=1;
for?i=50:100:(N*100-50)
????if?ask2_dem2(i)<=0.5?????%根據(jù)采樣信號幅度來判決,大于0.5為1,小于0.5為0
????????m2_sample(k)=0;
????else?
????????m2_sample(k)=1;
????end
????k=k+1;
end

%將抽樣結(jié)果轉(zhuǎn)換為不歸零碼型
for?k=1:(N/2)
????for?i=(100*k-99):(100*k)
?????????m2_sampletime(i)=m2_sample(k);
????end???
end

%清零處理
for?i=(100*(N/2)+1):(100*N)
????m2_sampletime(i)=0;
end


%
figure(4)
%將調(diào)制信號與解調(diào)還原的信號作對比
subplot(311)
plot(tm2_time(1:length(t)))
axis([0?0.001?-1?2])
title(‘調(diào)制信號‘)
grid?on;
subplot(312)
plot(task2_dem2(1:length(t)))
axis([0?0.001?-1?2])
title(‘通過LPF后的波形‘)
grid?on;
subplot(313)
plot(tm2_sampletime(1:length(t)))
axis([0?0.001?-1?2])
title(‘抽樣判決后波形‘)
grid?on;


?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2017-04-18?20:49??MASK\
?????目錄???????????0??2017-04-18?20:49??MASK\2ASK\
?????文件????????3071??2014-04-20?22:45??MASK\2ASK\ask22.m
?????文件?????????525??2014-04-16?22:58??MASK\2ASK\fftseq.m
?????目錄???????????0??2017-04-18?20:49??MASK\2ASK_4ASK_8ASK\
?????文件?????????251??2014-04-23?00:11??MASK\2ASK_4ASK_8ASK\2askBER_0_15.mat
?????文件?????????312??2014-04-23?00:11??MASK\2ASK_4ASK_8ASK\4askBER_0_15.mat
?????文件?????????320??2014-04-23?00:12??MASK\2ASK_4ASK_8ASK\8askBER_0_15.mat
?????文件????????1366??2014-04-21?00:10??MASK\2ASK_4ASK_8ASK\ASK.asv
?????文件????????1484??2014-04-21?23:18??MASK\2ASK_4ASK_8ASK\ASK.m
?????文件?????????146??2014-04-23?02:36??MASK\2ASK_4ASK_8ASK\BERplot.asv
?????文件?????????146??2014-04-23?02:39??MASK\2ASK_4ASK_8ASK\BERplot.m
?????文件????????1687??2014-04-21?22:49??MASK\2ASK_4ASK_8ASK\Copy_of_ASK.asv
?????文件????????1998??2014-04-22?15:25??MASK\2ASK_4ASK_8ASK\Copy_of_ASK.m
?????文件?????????351??2008-07-04?15:07??MASK\2ASK_4ASK_8ASK\F2T.m
?????文件?????????451??2008-09-05?08:17??MASK\2ASK_4ASK_8ASK\jd.m
?????文件?????????543??2014-04-23?01:06??MASK\2ASK_4ASK_8ASK\lpf.asv
?????文件?????????547??2014-04-24?19:34??MASK\2ASK_4ASK_8ASK\lpf.m
?????文件????????2179??2014-04-22?23:16??MASK\2ASK_4ASK_8ASK\my_2ASK.m
?????文件????????2757??2014-04-23?01:16??MASK\2ASK_4ASK_8ASK\my_4ASK.asv
?????文件????????2765??2014-04-24?19:26??MASK\2ASK_4ASK_8ASK\my_4ASK.m
?????文件????????3847??2014-04-23?00:52??MASK\2ASK_4ASK_8ASK\my_8ASK.asv
?????文件????????4672??2014-04-24?19:34??MASK\2ASK_4ASK_8ASK\my_8ASK.m
?????文件?????????493??2014-04-17?16:45??MASK\2ASK_4ASK_8ASK\T2F.asv
?????文件?????????567??2014-04-22?00:22??MASK\2ASK_4ASK_8ASK\T2F.m
?????文件????????1994??2014-04-22?16:11??MASK\2ASK_4ASK_8ASK\test_my_ASK.m
?????目錄???????????0??2017-04-18?20:49??MFSK\
?????目錄???????????0??2017-04-18?20:49??MFSK\2FSK\
?????文件?????????351??2014-04-24?19:51??MFSK\2FSK\F2T.m
?????文件????????1907??2014-04-24?19:51??MFSK\2FSK\FSK.m
?????文件?????????543??2014-04-24?19:51??MFSK\2FSK\lpf.m
............此處省略55個文件信息

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