小波.zip_小波消噪_小波阈值_阈值小波

clc; clear; close all; % 当前延拓模式是补零 oldmode = dwtmode('zpd'); %% 小波分解与重构 %装载信号 data = xlsread('1956-2011张家山月runoff.xlsx','sheet1'); s = data(12,:); % index = 1:672; % ts = 1; % fs = 1/ts; % t=1:ts:672; % N = length(s); % %画出原始信号 % figure(1); % plot(index,s); % ylable = ('jingliu'); % xlable = ('xuhao n'); %多尺度一维分解 [c,l] = wavedec(s,5,'db5'); % 重构第1～5层逼近系数 % a5 = wrcoef('a',c,l,'db5',5); % a6 = wrcoef('a',c,l,'db5',6); a5 = wrcoef('a',c,l,'db5',5); a4 = wrcoef('a',c,l,'db5',4); a3 = wrcoef('a',c,l,'db5',3); a2 = wrcoef('a',c,l,'db5',2); a1 = wrcoef('a',c,l,'db5',1); % % 显示逼近系数 % figure % subplot(6,1,1);plot(a6);ylabel('a6'); % subplot(6,1,2);plot(a5);ylabel('a5'); % subplot(6,1,3);plot(a4);ylabel('a4'); % subplot(6,1,4);plot(a3);ylabel('a3'); % subplot(6,1,5);plot(a2);ylabel('a2'); % subplot(6,1,6);plot(a1);ylabel('a1'); % xlabel('时间 t/s'); figure subplot(5,1,1);plot(a5);ylabel('a5'); subplot(5,1,2);plot(a4);ylabel('a4'); subplot(5,1,3);plot(a3);ylabel('a3'); subplot(5,1,4);plot(a2);ylabel('a2'); subplot(5,1,5);plot(a1);ylabel('a1'); xlabel('时间 t/s'); % 重构第1～5层细节系数 % d6 = wrcoef('a',c,l,'db5',6); d5 = wrcoef('d',c,l,'db5',5); d4 = wrcoef('d',c,l,'db5',4); d3 = wrcoef('d',c,l,'db5',3); d2 = wrcoef('d',c,l,'db5',2); d1 = wrcoef('d',c,l,'db5',1); % 显示细节系数 figure subplot(5,1,1);plot(d5);ylabel('d5'); subplot(5,1,2);plot(d4);ylabel('d4'); subplot(5,1,3);plot(d3);ylabel('d3'); subplot(5,1,4);plot(d2);ylabel('d2'); subplot(5,1,5);plot(d1);ylabel('d1'); xlabel('时间 t/年'); % figure % subplot(6,1,1);plot(d6);ylabel('d6'); % subplot(6,1,2);plot(d5);ylabel('d5'); % subplot(6,1,3);plot(d4);ylabel('d4'); % subplot(6,1,4);plot(d3);ylabel('d3'); % subplot(6,1,5);plot(d2);ylabel('d2'); % subplot(6,1,6);plot(d1);ylabel('d1'); % xlabel('时间 t/年'); xxk = []; xxk(:,1) = a1; xxk(:,2) = a2; xxk(:,3) = a3; xxk(:,4) = a4; xxk(:,5) = a5; xxk(:,6) = d1; xxk(:,7) = d2; xxk(:,8) = d3; xxk(:,9) = d4; xxk(:,10) = d5; % xxk(:,11) = d6; % xxk(:,12) = a6; xlswrite('xiaobo.xlsx',xxk); % 第1层细节信号的包络谱 yh = hilbert(d3); aabs = abs(yh); % 包络的绝对值 aabs = aabs - mean(aabs); aangle = unwrap(angle(yh)); % 包络的相位 af = diff(aangle)/2/pi; % 包络的瞬时频率，差分代替微分计算 % NFFT = 2^nextpow2(N); NFFT = 2^nextpow2(1024*4); % 改善栅栏效应 f = fs*linspace(0,1,NFFT); YH = fft(yh, NFFT)/N; % Hilbert变换复信号的频谱 A = fft(aabs, NFFT)/N; % 包络的频谱 figure plot(f,abs(YH)) title('原始复信号的Hilbert谱') xlabel('频率f (Hz)') ylabel('|YH(f)|') figure subplot(221) plot(t, aabs') title('包络的绝对值') legend('包络分析结果', '真实包络') subplot(222) plot(t, aangle) title('调制信号的相位') subplot(223) plot(t(1:end-1), af*fs) title('调制信号的瞬时频率') subplot(224) plot(f,abs(A)) title('包络的频谱') xlabel('频率f (Hz)') ylabel('|A(f)|') % 恢复延拓模式 dwtmode(oldmode); % % % c = wavedec2(a,3,'db1'); % % %提取系数 % % cA3 = appcoef(C,L,'db1',3); % % cD3 = detcoef(C,L,3); % % cD2 = detcoef(C,L,2); % % cD1 = detcoef(C,L,1); % % % % %重构系数 % % A3 = wrcoef('a',C,L,'db1',3); % % D1 = wrcoef('d',C,L,'db1',2); % % D2 = wrcoef('d',C,L,'db1',1); % % D3 = wrcoef('d',C,L,'db1',2); % % % % %重构原始信号 % % A0 = waverec(C,L,'db1'); % % % % %重构最大误差 % % Err = max(abs(a-A0)); % %