{"id":819,"date":"2020-08-11T17:55:24","date_gmt":"2020-08-11T09:55:24","guid":{"rendered":"http:\/\/www.growlove.cn\/blog\/?p=819"},"modified":"2020-08-11T17:55:24","modified_gmt":"2020-08-11T09:55:24","slug":"%e8%af%ad%e9%9f%b3%e4%bf%a1%e5%8f%b7%e6%bb%a4%e6%b3%a2%e5%8e%bb%e5%99%aa","status":"publish","type":"post","link":"https:\/\/growlove.cn\/index.php\/2020\/08\/11\/%e8%af%ad%e9%9f%b3%e4%bf%a1%e5%8f%b7%e6%bb%a4%e6%b3%a2%e5%8e%bb%e5%99%aa\/","title":{"rendered":"\u8bed\u97f3\u4fe1\u53f7\u6ee4\u6ce2\u53bb\u566a"},"content":{"rendered":"<p>&nbsp;<\/p>\n<p><strong>\u8bed\u97f3\u4fe1\u53f7\u6ee4\u6ce2\u53bb\u566a<\/strong><\/p>\n<p>\u2014\u2014<strong>\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\u00a0 <\/strong><\/p>\n<p>&nbsp;<\/p>\n<p>\u6458\u00a0 \u8981 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<\/strong><strong>\u8bfe\u7a0b\u8bbe\u8ba1\u76ee\u7684<\/strong><\/p>\n<p>\u300a\u6570\u5b57\u4fe1\u53f7\u5904\u7406\u300b\u8bfe\u7a0b\u8bbe\u8ba1\u662f\u5728\u5b66\u751f\u5b8c\u6210\u6570\u5b57\u4fe1\u53f7\u5904\u7406\u548cMATLAB\u7684\u7ed3\u5408\u540e\u7684\u57fa\u672c\u5b9e\u9a8c\u4ee5\u540e\u5f00\u8bbe\u7684\u3002\u672c\u8bfe\u7a0b\u8bbe\u8ba1\u7684\u76ee\u7684\u662f\u4e3a\u4e86\u8ba9\u6211\u4eec\u7efc\u5408\u6570\u5b57\u4fe1\u53f7\u5904\u7406\u548cMATLAB\u5e76\u5b9e\u73b0\u4e00\u4e2a\u8f83\u4e3a\u5b8c\u6574\u7684\u5c0f\u578b\u6ee4\u6ce2\u7cfb\u7edf\u3002\u8fd9\u4e00\u70b9\u4e0e\u9a8c\u8bc1\u6027\u7684\u57fa\u672c\u5b9e\u9a8c\u6709\u672c\u8d28\u6027\u7684\u533a\u522b\u3002\u5f00\u8bbe\u8bfe\u7a0b\u8bbe\u8ba1\u73af\u8282\u7684\u4e3b\u8981\u76ee\u7684\u662f\u901a\u8fc7\u7cfb\u7edf\u8bbe\u8ba1\u3001\u8f6f\u4ef6\u4eff\u771f\u3001\u7a0b\u5e8f\u5b89\u6392\u4e0e\u8c03\u8bd5\u3001\u5199\u5b9e\u4e60\u62a5\u544a\u7b49\u6b65\u9aa4\uff0c\u4f7f\u5b66\u751f\u521d\u6b65\u638c\u63e1\u5de5\u7a0b\u8bbe\u8ba1\u7684\u5177\u4f53\u6b65\u9aa4\u548c\u65b9\u6cd5\uff0c\u63d0\u9ad8\u5206\u6790\u95ee\u9898\u548c\u89e3\u51b3\u95ee\u9898\u7684\u80fd\u529b\uff0c\u63d0\u9ad8\u5b9e\u9645\u5e94\u7528\u6c34\u5e73\u3002<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>1.2 <\/strong><strong>\u8bfe\u7a0b\u8bbe\u8ba1\u7684\u8981\u6c42<\/strong><\/p>\n<p>\uff081\uff09\u5b66\u4f1a MATLAB \u7684\u4f7f\u7528\uff0c\u638c\u63e1 MATLAB \u7684\u7a0b\u5e8f\u8bbe\u8ba1\u65b9\u6cd5\uff1b<\/p>\n<p>\uff082\uff09\u6ee4\u6ce2\u5668\u6307\u6807\u5fc5\u987b\u7b26\u5408\u5de5\u7a0b\u5b9e\u9645\uff0c\u6839\u636e\u6a21\u62df\u6ee4\u6ce2\u5668\u7684\u6027\u80fd\u6307\u6807\uff0c\u786e\u5b9a\u6570\u5b57\u6ee4\u6ce2\u5668\u6307\u6807\uff1b<\/p>\n<p>\uff083\uff09\u91c7\u7528\u7a97\u51fd\u6570\u6cd5\uff0c\u8bbe\u8ba1\u6ee1\u8db3\u4e0a\u8ff0\u6027\u80fd\u6307\u6807\u8981\u6c42\u7684FIR\u578b\u6570\u5b57\u4f4e\u901a\u6ee4\u6ce2\u5668\uff1b<\/p>\n<p>\uff084\uff09\u8bbe\u8ba1\u5b8c\u540e\u5e94\u68c0\u67e5\u5176\u9891\u7387\u54cd\u5e94\u66f2\u7ebf\u662f\u5426\u6ee1\u8db3\u6307\u6807\uff1b<\/p>\n<p>\uff085\uff09\u5904\u7406\u7ed3\u679c\u548c\u5206\u6790\u7ed3\u8bba\u5e94\u8be5\u4e00\u81f4\uff0c\u800c\u4e14\u5e94\u7b26\u5408\u7406\u8bba\uff1b<\/p>\n<p>\uff086\uff09\u72ec\u7acb\u5b8c\u6210\u8bfe\u7a0b\u8bbe\u8ba1\u5e76\u6309\u8981\u6c42\u7f16\u5199\u8bfe\u7a0b\u8bbe\u8ba1\u62a5\u544a\u4e66\uff1b<\/p>\n<p>&nbsp;<\/p>\n<p><strong>1.3 <\/strong><strong>\u8bbe\u8ba1\u5e73\u53f0<\/strong><\/p>\n<p>\u672c\u6b21\u8bfe\u7a0b\u8bbe\u8ba1\u662f\u5728MATLAB\u8f6f\u4ef6\u5e73\u53f0\u4e0a\u8fdb\u884c\u7684\u3002MATLAB\u662f\u77e9\u9635\u5b9e\u9a8c\u5ba4\uff08MATRIX LABORATORY\uff09\u7684\u7b80\u79f0\uff0c\u662f\u7f8e\u56fdMATHWORKS\u516c\u53f8\u63a8\u51fa\u7684\u5177\u6709\u5f3a\u5927\u6570\u503c\u5206\u6790\u3001\u77e9\u9635\u8fd0\u7b97\u3001\u56fe\u5f62\u7ed8\u5236\u548c\u6570\u636e\u5904\u7406\u7b49\u529f\u80fd\u7684\u8f6f\u4ef6\uff0c\u73b0\u5df2\u5e7f\u6cdb\u5e94\u7528\u5230\u6559\u5b66\u3001\u79d1\u7814\u3001\u5de5\u7a0b\u8bbe\u8ba1\u7b49\u9886\u57df[2]\u3002\u968f\u7740MATLAB\u8f6f\u4ef6\u4fe1\u53f7\u5904\u7406\u5de5\u5177\u7bb1\u7684\u63a8\u51fa\uff0cMATLAB\u5df2\u6210\u4e3a\u4fe1\u606f\u5904\u7406\uff0c\u7279\u522b\u662f\u6570\u5b57\u4fe1\u53f7\u5904\u7406DSP\u5e94\u7528\u4e2d\u5206\u6790\u548c\u8bbe\u8ba1\u7684\u4e3b\u8981\u5de5\u5177\u3002\u5c31MATLAB\u4fe1\u53f7\u5904\u7406\u4e2d\u7684\u6ee4\u6ce2\u5668\u8bbe\u8ba1\u800c\u8a00\uff0c\u5728\u5f88\u5927\u7a0b\u5ea6\u4e0a\u80fd\u5feb\u901f\u6709\u6548\u5730\u5b9e\u73b0\u6ee4\u6ce2\u5668\u7684\u5206\u6790\u3001\u8bbe\u8ba1\u53ca\u4eff\u771f\uff0c\u5927\u5927\u8282\u7ea6\u4e86\u8bbe\u8ba1\u65f6\u95f4\uff0c\u76f8\u5bf9\u4f20\u7edf\u8bbe\u8ba1\u800c\u8a00\uff0c\u7b80\u5316\u4e86\u6ee4\u6ce2\u5668\u8bbe\u8ba1\u7684\u96be\u5ea6\u3002<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>2 <\/strong><strong>\u8bbe\u8ba1\u539f\u7406<\/strong><\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>2.1<\/strong>\u7528\u9ea6\u514b\u98ce\u91c7\u96c6\u4e00\u6bb5\u53cc\u97f3\u9891\u4fe1\u53f7\uff0c\u7ed8\u5236\u6ce2\u5f62\u5e76\u89c2\u5bdf\u5176\u9891\u8c31\uff0c\u7ed9\u5b9a\u76f8\u5e94\u6280\u672f\u6307\u6807\uff0c\u7528\u53cc\u7ebf\u6027\u53d8\u6362\u6cd5\u8bbe\u8ba1\u7684\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\uff0c\u5bf9\u8be5\u53cc\u97f3\u9891\u4fe1\u53f7\u8fdb\u884c\u6ee4\u6ce2\u53bb\u566a\u5904\u7406\uff0c\u6bd4\u8f83\u6ee4\u6ce2\u524d\u540e\u7684\u6ce2\u5f62\u548c\u9891\u8c31\u5e76\u8fdb\u884c\u5206\u6790\u3002<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>2.2 <\/strong>\u6a21\u62df\u542b\u566a\u8bed\u97f3\u4fe1\u53f7\u5408\u6210\uff1b<\/p>\n<p>\u5728MATLAB\u8f6f\u4ef6\u5e73\u53f0\u4e0b\uff0c\u7ed9\u539f\u59cb\u7684\u8bed\u97f3\u4fe1\u53f7\u53e0\u52a0\u4e0a\u566a\u58f0\uff0c\u566a\u58f0\u7c7b\u578b\u5206\u4e3a\u5982\u4e0b\u51e0\u79cd\uff1aa\u767d\u566a\u58f0\uff1bb\u5355\u9891\u566a\u8272\uff08\u6b63\u5f26\u5e72\u6270\uff09\uff1bc\u591a\u9891\u566a\u58f0\uff08\u591a\u6b63\u5f26\u5e72\u6270\uff09\uff1bd\u5176\u5b83\u5e72\u6270\u3002\u7ed8\u51fa\u53e0\u52a0\u566a\u58f0\u540e\u7684\u8bed\u97f3\u4fe1\u53f7\u65f6\u57df\u548c\u9891\u8c31\u56fe\uff0c\u5728\u89c6\u89c9\u4e0a\u4e0e\u539f\u59cb\u8bed\u97f3\u4fe1\u53f7\u56fe\u5f62\u5bf9\u6bd4\uff0c\u4e5f\u53ef\u901a\u8fc7Windows\u64ad\u653e\u8f6f\u4ef6\u4ece\u542c\u89c9\u4e0a\u8fdb\u884c\u5bf9\u6bd4\uff0c\u5206\u6790\u542b\u566a\u8bed\u97f3\u4fe1\u53f7\u9891\u8c31\u548c\u65f6\u57df\u6ce2\u5f62\u7684\u6539\u53d8\u3002<\/p>\n<p><strong>2.3 <\/strong>\u6570\u5b57\u6ee4\u6ce2\u5668\u8bbe\u8ba1\u53ca\u6ee4\u6ce2\uff1b<\/p>\n<p>\u5df2\u77e5\u6570\u5b57\u6ee4\u6ce2\u5668\u7684\u6027\u80fd\u6307\u6807\u4e3a\uff1a\uff0c\u91c7\u7528\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1\u4f4e\u901a\u578bFIR\u6ee4\u6ce2\u5668\u6765\u5bf9\u53e0\u52a0\u566a\u58f0\u524d\u540e\u7684\u8bed\u97f3\u4fe1\u53f7\u8fdb\u884c\u6ee4\u6ce2\u5904\u7406\uff0c\u7ed8\u51fa\u6ee4\u6ce2\u5668\u7684\u9891\u57df\u54cd\u5e94\u3001\u6ee4\u6ce2\u540e\u4fe1\u53f7\u7684\u65f6\u57df\u6ce2\u5f62\u548c\u9891\u8c31\uff0c\u5e76\u5bf9\u6ee4\u6ce2\u524d\u540e\u7684\u4fe1\u53f7\u8fdb\u884c\u5bf9\u6bd4\uff0c\u5206\u6790\u4fe1\u53f7\u7684\u53d8\u5316\u3002\u5206\u522b\u7ed8\u5236\u51fa\u7406\u60f3\u51b2\u6fc0\u54cd\u5e94\u548c\u5b9e\u9645\u51b2\u6fc0\u54cd\u5e94\u7ed3\u679c\u56fe\u3002\u5e76\u4e14\u7ed9\u51fa\u5e45\u5ea6\u54cd\u5e94\u7ed3\u679c\u56fe\u3002<\/p>\n<p>&nbsp;<\/p>\n<p>3 <strong>\u8bbe\u8ba1\u6b65\u9aa4<\/strong><\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>3.1<\/strong><strong>\u8bbe\u8ba1\u6d41\u7a0b\u56fe<\/strong><\/p>\n<p>\u8bed\u97f3\u4fe1\u53f7\u6ee4\u6ce2\u53bb\u566a\u2014\u2014\u4f7f\u7528\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\u7684\u8bbe\u8ba1\u6d41\u7a0b\u5982\u56fe3.1\u6240\u793a\uff1a<\/p>\n<p><strong>\u00a0<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-820\" src=\"http:\/\/bestgrow-bestgrow.stor.applinzi.com\/uploads\/2020\/08\/111.png\" alt=\"\" width=\"635\" height=\"519\" \/><\/strong><\/p>\n<p>\u56fe3.1\u00a0\u00a0 \u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\u5bf9\u53cc\u97f3\u9891\u4fe1\u53f7\u53bb\u566a\u6d41\u7a0b\u56fe<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>3.2<\/strong><strong>\u8bed\u97f3\u4fe1\u53f7\u7684\u91c7\u96c6<\/strong><\/p>\n<p>\u70b9\u51fbwindows\u7cfb\u7edf\u684c\u9762\u7684\u201c\u5f00\u59cb\u201d\u6309\u94ae\uff0c\u70b9\u51fb\u5f00\u59cb\u83dc\u5355\u680f\u91cc\u7684\u201c\u9644\u4ef6\u201d\uff0c\u9009\u62e9\u201c\u5f55\u97f3\u673a\u201d\u9009\u9879\uff0c\u70b9\u51fb\u5f55\u97f3\u673a\u201c\u6587\u4ef6\u201d\u9009\u9879\uff0c\u8fdb\u5165\u201c\u58f0\u97f3\u9009\u5b9a\u201d\u8bbe\u7f6e\uff0c\u628a\u5c5e\u6027\u4e00\u680f\u8bbe\u7f6e\u6210\u201c8000Hz\uff0c8\u4f4d\uff0c\u5355\u58f0\u9053\uff0c7KB\/\u79d2\u201d(\u89c1\u56fe3.2)\u3002\u70b9\u51fb\u786e\u5b9a\uff0c\u7136\u540e\u5f00\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7\u7684\u91c7\u96c6\uff0c\u91c7\u96c6\u65f6\u95f4\u4e3a2\u20143\u79d2\u5de6\u53f3\u4e3a\u6700\u4f73\u3002\u91c7\u96c6\u7684\u58f0\u97f3\u6587\u4ef6\u4ee5\u201c.wav\u201d\u683c\u5f0f\u5b58\u50a8\uff08\u89c1\u56fe3.3\uff09\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-821\" src=\"http:\/\/bestgrow-bestgrow.stor.applinzi.com\/uploads\/2020\/08\/222.png\" alt=\"\" width=\"344\" height=\"181\" \/><\/p>\n<p>\u56fe3.2\u00a0\u00a0\u00a0 \u91c7\u96c6\u58f0\u97f3\u7684\u53c2\u6570\u8bbe\u7f6e<\/p>\n<p>&nbsp;<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-822\" src=\"http:\/\/bestgrow-bestgrow.stor.applinzi.com\/uploads\/2020\/08\/333.png\" alt=\"\" width=\"276\" height=\"194\" \/><\/p>\n<p>\u56fe3.3\u00a0\u00a0 \u91c7\u96c6\u58f0\u97f3<\/p>\n<p>&nbsp;<\/p>\n<p><strong>3.3<\/strong><strong>\u8bed\u97f3\u4fe1\u53f7\u7684\u9891\u8c31\u5206\u6790<\/strong><\/p>\n<p>\u5728MATLAB\u4e2d\u7f16\u8f91m\u51fd\u6570\uff0c\u4f7f\u7528wavread\u51fd\u6570\u8bfb\u53d6\u91c7\u96c6\u7684\u58f0\u97f3\u6587\u4ef6\uff08.wav)\u5c06\u5b83\u8d4b\u503c\u7ed9\u67d0\u4e00\u5411\u91cf\uff0c\u518d\u5bf9\u5176\u8fdb\u884c\u91c7\u6837,\u7136\u540e\u4f7f\u7528plot\u8bed\u53e5\u753b\u51fa\u76f8\u5173\u7684\u9891\u8c31\u56fe\u5f62\u3002<\/p>\n<p>\uff081\uff09Wavread\u51fd\u6570\u8c03\u7528\u683c\u5f0f\uff1a<\/p>\n<p>[y,fs,nbits]=wavread(file)<\/p>\n<p>\u529f\u80fd\u8bf4\u660e\uff1a\u91c7\u6837\u503c\u653e\u5728\u5411\u91cfx\u4e2d\uff0cfs\u8868\u793a\u91c7\u6837\u9891\u7387\uff08Hz\uff09\uff0cbits\u8868\u793a\u91c7\u6837\u4f4d\u6570\u3002<\/p>\n<p>\uff082\uff09\u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362\u7b97\u6cd5FFT\u8ba1\u7b97DFT\u7684\u51fd\u6570fft,\u5176\u8c03\u7528\u683c\u5f0f\u5982\u4e0b\uff1a<\/p>\n<p>Xk=fft(x,n)<\/p>\n<p>\u53c2\u6570x\u4e3a\u88ab\u53d8\u6362\u7684\u65f6\u57df\u5e8f\u5217\u5411\u91cf\uff0cN\u662fDFT\u53d8\u6362\u533a\u95f4\u957f\u5ea6\uff0c\u5f53n\u5927\u4e8ex\u7684\u957f\u5ea6\u65f6\uff0cfft\u51fd\u6570\u81ea\u52a8\u5728x\u540e\u9762\u8865\u96f6\u3002\uff0c\u5f53n\u5c0f\u4e8exn\u7684\u957f\u5ea6\u65f6\uff0cfft\u51fd\u6570\u8ba1\u7b97x\u7684\u524dn\u4e2a\u5143\u7d20\uff0c\u5ffd\u7565\u5176\u540e\u9762\u7684\u5143\u7d20\u3002<\/p>\n<p>\u5728\u672c\u6b21\u8bfe\u7a0b\u8bbe\u8ba1\u4e2d\uff0c\u6211\u4eec\u5229\u7528fft\u51fd\u6570\u5bf9\u53cc\u97f3\u9891\u4fe1\u53f7\u8fdb\u884c\u5feb\u901f\u5085\u91cc\u53f6\u53d8\u6362\uff0c\u5c31\u53ef\u4ee5\u5f97\u5230\u4fe1\u53f7\u7684\u9891\u8c31\u7279\u6027\u3002<\/p>\n<p>\uff083\uff09\u58f0\u97f3\u91c7\u6837\u6587\u4ef6\u8bfb\u53d6\u7684\u7a0b\u5e8f\uff08\u6587\u4ef6\u540d\uff1axiaomiao.wav)\uff1b<\/p>\n<p>\u53cc\u97f3\u9891\u4fe1\u53f7\u7684\u63d0\u53d6\uff1a<\/p>\n<p>[x,fs,bits]=wavread(&#8216;D:\\MATLAB7\\work\\xiaomiao.wav&#8217;); \u00a0% \u8f93\u5165\u53c2\u6570\u4e3a\u6587\u4ef6\u7684\u5168\u8def\u5f84\u548c\u6587\u4ef6\u540d\uff0c\u8f93\u51fa\u7684\u7b2c\u4e00\u4e2a\u53c2\u6570\u662f\u6bcf\u4e2a\u6837\u672c\u7684\u503c\uff0cfs\u662f\u751f\u6210\u8be5\u6ce2\u5f62\u6587\u4ef6\u65f6\u7684\u91c7\u6837\u7387\uff0cbits\u662f\u6ce2\u5f62\u6587\u4ef6\u6bcf\u6837\u672c\u7684\u7f16\u7801\u4f4d\u6570\u3002<\/p>\n<p>sound(x,fs,bits);\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u6309\u6307\u5b9a\u7684\u91c7\u6837\u7387\u548c\u6bcf\u6837\u672c\u7f16\u7801\u4f4d\u6570\u56de\u653e<\/p>\n<p>N=length(x);\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u4fe1\u53f7x\u7684\u957f\u5ea6<\/p>\n<p>fn=2200;\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u5355\u9891\u566a\u58f0\u9891\u7387\uff0c\u6b64\u53c2\u6570\u53ef\u6539<\/p>\n<p>t=0:1\/fs:(N-1)\/fs;\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u65f6\u95f4\u8303\u56f4\uff0c\u6837\u672c\u6570\u9664\u4ee5\u91c7\u6837\u9891\u7387<\/p>\n<p>x=x(:,1)&#8217;; y=x+sin(fn*2*pi*t);<\/p>\n<p>sound(y,fs,bits);\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u5e94\u8be5\u53ef\u4ee5\u660e\u663e\u542c\u51fa\u6709\u5c16\u9510\u7684\u5355\u9891\u5578\u53eb\u58f0<\/p>\n<p>X=abs(fft(x));\u00a0 Y=abs(fft(y));\u00a0 \u00a0\u00a0% \u5bf9\u539f\u59cb\u4fe1\u53f7\u548c\u52a0\u566a\u4fe1\u53f7\u8fdb\u884cfft\u53d8\u6362,\u53d6\u5e45\u5ea6\u8c31<\/p>\n<p>X=X(1:N\/2); Y=Y(1:N\/2); \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u622a\u53d6\u524d\u534a\u90e8\u5206<\/p>\n<p>deltaf=fs\/N;\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u9891\u8c31\u7684\u8c31\u7ebf\u95f4\u9694<\/p>\n<p>f=0:deltaf:fs\/2-deltaf;\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u9891\u8c31\u9891\u7387\u8303\u56f4<\/p>\n<p>&nbsp;<\/p>\n<p>\u5f97\u5230\u7684\u539f\u59cb\u8bed\u97f3\u4fe1\u53f7\u548c\u52a0\u4e0a\u566a\u97f3\u540e\u7684\u8bed\u97f3\u4fe1\u53f7\u7684\u65f6\u57df\u6ce2\u5f62\u548c\u9891\u8c31\u56fe\u5982\u56fe3.4\u6240\u793a\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-823\" src=\"http:\/\/bestgrow-bestgrow.stor.applinzi.com\/uploads\/2020\/08\/444.png\" alt=\"\" width=\"571\" height=\"504\" \/><\/p>\n<p>\u56fe3.4\u00a0\u00a0 \u539f\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7\u548c\u52a0\u566a\u540e\u4fe1\u53f7\u7684\u65f6\u57df\u548c\u9891\u8c31\u56fe<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>3.4<\/strong><strong>\u6ee4\u6ce2\u5668\u8bbe\u8ba1<\/strong><\/p>\n<p><strong>\u00a0\u00a0\u00a0 <\/strong>\u8bbe\u8ba1\u6307\u6807\uff1a\u901a\u5e26\u622a\u6b62\u9891\u7387\u4e3a2000Hz\uff0c\u963b\u5e26\u622a\u6b62\u9891\u7387\u4e3a2150Hz\uff0c\u901a\u5e26\u6ce2\u7eb9\u4e3a1dB\uff0c\u963b\u5e26\u6ce2\u7eb9\u4e3a35dB\uff0c\u7528\u53cc\u7ebf\u6027\u53d8\u6362\u6cd5\u8bbe\u8ba1\u7684\u4e00\u4e2a\u6ee1\u8db3\u4e0a\u8ff0\u6307\u6807\u7684\u5207\u6bd4\u96ea\u592bI\u578b\u6ee4\u6ce2\u5668<\/p>\n<p>\u53cc\u7ebf\u6027\u53d8\u6362\u6cd5\u8bbe\u8ba1\u5207\u6bd4\u96ea\u592bI\u578b\u6ee4\u6ce2\u5668<\/p>\n<p>fs=22050;<\/p>\n<p>[x,fs,bits]=wavread(&#8216;D:\\\u6211\u7684\u7956\u56fd22.wav&#8217;);<\/p>\n<p>sound(x,fs,bits);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u6309\u6307\u5b9a\u7684\u91c7\u6837\u7387\u548c\u6bcf\u6837\u672c\u7f16\u7801\u4f4d\u6570\u56de\u653e<\/p>\n<p>fn=2200;\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u5355\u9891\u566a\u58f0\u9891\u7387\uff0c\u6b64\u53c2\u6570\u53ef\u6539<\/p>\n<p>t=0:1\/fs:(N-1)\/fs;\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u8ba1\u7b97\u65f6\u95f4\u8303\u56f4\uff0c\u6837\u672c\u6570\u9664\u4ee5\u91c7\u6837\u9891\u7387<\/p>\n<p>%x=x(:,1)&#8217;;<\/p>\n<p>y=x+awgn(x,10);<\/p>\n<p>N=length(y);<\/p>\n<p>%sound(y,fs,bits);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u5e94\u8be5\u53ef\u4ee5\u660e\u663e\u542c\u51fa\u6709\u5c16\u9510\u7684\u5355\u9891\u5578\u53eb\u58f0<\/p>\n<p>X=abs(fft(x));\u00a0 Y=abs(fft(y));\u00a0\u00a0\u00a0 % \u5bf9\u539f\u59cb\u4fe1\u53f7\u548c\u52a0\u566a\u4fe1\u53f7\u8fdb\u884cfft\u53d8\u6362,\u53d6\u5e45\u5ea6\u8c31<\/p>\n<p>%X=X(1:N\/2); Y=Y(1:N\/2);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u622a\u53d6\u524d\u534a\u90e8\u5206<\/p>\n<p>%deltaf=fs\/N;\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u8ba1\u7b97\u9891\u8c31\u7684\u8c31\u7ebf\u95f4\u9694<\/p>\n<p>%f=0:deltaf:fs\/2-deltaf;\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0% \u8ba1\u7b97\u9891\u8c31\u9891\u7387\u8303\u56f4<\/p>\n<p>y_p=fft(y,N);<\/p>\n<p>f=fs*(0:N\/2-1)\/N;<\/p>\n<p>figure(1);<\/p>\n<p>subplot(2,1,1);<\/p>\n<p>plot(y);<\/p>\n<p>title(&#8216;\u539f\u59cb\u8bed\u97f3\u4fe1\u53f7\u91c7\u6837\u540e\u65f6\u57df\u6ce2\u5f62&#8217;);<\/p>\n<p>xlabel(&#8216;\u65f6\u95f4\u8f74&#8217;);<\/p>\n<p>ylabel(&#8216;\u5e45\u5ea6A&#8217;);<\/p>\n<p>subplot(2,1,2);<\/p>\n<p>plot(f,abs(y_p(1:N\/2)));<\/p>\n<p>title(&#8216;\u539f\u59cb\u8bed\u97f3\u4fe1\u53f7\u91c7\u6837\u540e\u9891\u8c31\u56fe&#8217;);<\/p>\n<p>xlabel(&#8216;\u9891\u7387HZ&#8217;);<\/p>\n<p>ylabel(&#8216;\u9891\u7387\u5e45\u503c&#8217;);<\/p>\n<p>&nbsp;<\/p>\n<p>\u5f97\u5230\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\u7684\u5e45\u5ea6\u548c\u76f8\u4f4d\u8c31\u5982\u56fe3.5\u6240\u793a\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-824\" src=\"http:\/\/bestgrow-bestgrow.stor.applinzi.com\/uploads\/2020\/08\/555.png\" alt=\"\" width=\"606\" height=\"521\" \/><\/p>\n<p>\u56fe3.5\u00a0 \u5207\u6bd4\u96ea\u592b\u6ee4\u6ce2\u5668\u7684\u5e45\u5ea6\u548c\u76f8\u4f4d\u8c31<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p>3.5\u53cc\u97f3\u9891\u7684\u6ee4\u6ce2\u7a0b\u5e8f\u53ca\u6ee4\u6ce2\u6548\u679c\u56fe<\/p>\n<p>\u6ee4\u6ce2\u7a0b\u5e8f\uff1a<\/p>\n<p>y_fil=filter(b,a,y);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u7528\u8bbe\u8ba1\u597d\u7684\u6ee4\u6ce2\u5668\u5bf9y\u8fdb\u884c\u6ee4\u6ce2<\/p>\n<p>Y_fil=abs(fft(y_fil));Y_fil=Y_fil(1:N\/2); \u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u9891\u8c31\u53d6\u524d\u4e00\u534a<\/p>\n<p>&nbsp;<\/p>\n<p>\u753b\u51fa\u6ee4\u6ce2\u524d\u540e\u53cc\u97f3\u9891\u4fe1\u53f7\u7684\u65f6\u57df\u548c\u9891\u8c31\u56fe\u5982\u56fe3.6\u6240\u793a\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-825\" src=\"http:\/\/bestgrow-bestgrow.stor.applinzi.com\/uploads\/2020\/08\/666.png\" alt=\"\" width=\"738\" height=\"597\" \/><\/p>\n<p>\u56fe3.6\u00a0 \u6ee4\u6ce2\u524d\u540e\u53cc\u97f3\u9891\u4fe1\u53f7\u7684\u65f6\u57df\u548c\u9891\u8c31\u56fe<\/p>\n<p>&nbsp;<\/p>\n<p><strong>3.6<\/strong><strong>\u7ed3\u679c\u5206\u6790<\/strong><\/p>\n<p>\u5728MATLAB\u4e2d\uff0c\u7ecfsound\u51fd\u6570\uff0c\u5bf9\u7ecf\u8fc7\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\u4e4b\u540e\u7684\u4fe1\u53f7\u8fdb\u884c\u56de\u653e\uff0c\u53ef\u4ee5\u542c\u51fa\u6ee4\u6ce2\u4e4b\u540e\u7684\u4fe1\u53f7\u6bd4\u539f\u59cb\u4fe1\u53f7\u66f4\u6e05\u6670\u4e00\u4e9b\uff0c\u6e05\u9664\u4e86\u73af\u5883\u566a\u97f3\u3002<\/p>\n<p>\u901a\u8fc7\u4ee5\u4e0b\u8bed\u53e5\u6765\u8fdb\u884c\u8bed\u97f3\u4fe1\u53f7\u56de\u653e\u6bd4\u8f83\uff1a<\/p>\n<p>sound\uff08x\uff0cfs\uff0cbits\uff09\u00a0\u00a0\u00a0\u00a0\u00a0 %\u64ad\u653e\u539f\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7<\/p>\n<p>sound\uff08y\uff0cfs\uff0cbits\uff09\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 %\u64ad\u653e\u52a0\u566a\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7<\/p>\n<p>sound\uff08y_fil\uff0cfs\uff0cbits\uff09\u00a0\u00a0 %\u64ad\u653e\u7ecf\u8fc7\u6ee4\u6ce2\u5904\u7406\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7<\/p>\n<p>\u6240\u5f97\u7ed3\u679c\u8bc1\u660e\u4e86\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\u53bb\u566a\u8bbe\u8ba1\u6210\u529f\u3002<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>4 <\/strong><strong>\u51fa\u73b0\u7684\u95ee\u9898\u53ca\u89e3\u51b3\u65b9\u6cd5<\/strong><\/p>\n<p>\u5728\u8fd9\u6b21\u7684\u8bfe\u7a0b\u8bbe\u8ba1\u4e2d\uff0c\u7531\u4e8e\u7406\u8bba\u77e5\u8bc6\u7684\u4e0d\u8e0f\u5b9e\u4ee5\u53ca\u5176\u4ed6\u5404\u79cd\u539f\u56e0\uff0c\u6211\u4eec\u9047\u5230\u4e86\u4e0d\u5c11\u95ee\u9898\u3002<\/p>\n<p>\uff081\uff09\u5728\u8fdb\u884c\u53cc\u97f3\u9891\u4fe1\u53f7\u63d0\u53d6\u65f6\uff0c\u8fdb\u8fc7\u591a\u6b21\u5f55\u53d6\u624d\u5f97\u5230\u7406\u60f3\u7684\u53cc\u97f3\u9891\u4fe1\u53f7\uff0c\u5728\u5f97\u5230\u7406\u60f3\u7684\u6ce2\u5f62\u65f6\uff0c\u901a\u8fc7\u591a\u6b21\u5c1d\u8bd5\uff0c\u548c\u67e5\u627e\u4e66\u7c4d\u53ca\u540c\u5b66\u8ba8\u8bba\uff0c\u6700\u540e\u731c\u5f97\u5230\u7406\u60f3\u7684\u53cc\u97f3\u9891\u4fe1\u53f7\u7684\u65f6\u57df\u56fe\u548c\u9891\u8c31\u56fe<\/p>\n<p>\uff082\uff09\u5728\u8fd0\u7528Matlab\u8bbe\u8ba1\u6ee4\u6ce2\u5668\u65f6\uff0c\u5f53\u7f16\u8f91\u5b8c\u524d\u9762\u4e24\u6761\u7a0b\u5e8f\u65f6\u65e0\u6cd5\u653e\u51fa\u58f0\u97f3\uff0c\u540e\u6765\u53d1\u73b0\u6211\u4eec\u5e94\u5f53\u628a\u91c7\u96c6\u7684\u53cc\u97f3\u9891\u4fe1\u53f7wav\u6587\u4ef6\u653e\u5230Matlab\u7684work\u6587\u4ef6\u5939\u4e2d\u3002<\/p>\n<p>\uff083\uff09\u8fd8\u8981\u5728\u6ee4\u6ce2\u5668\u6027\u80fd\u66f2\u7ebf\u7684As\u5904\u753b\u4e00\u6839\u7ad6\u7ebf\uff0c\u8fd9\u6837\u66f4\u65b9\u4fbf\u770b\u51fa\u7ed3\u679c\u3002<\/p>\n<p>\uff084\uff09\u6240\u6709\u7684\u65f6\u95f4\u6ce2\u5f62\u6a2a\u5750\u6807\u90fd\u8981\u5316\u4e3a\u65f6\u95f4\uff0c\u6ee4\u6ce2\u524d\u540e\u9891\u8c31\u7684\u6a2a\u5750\u6807\u5e94\u662f\u9891\u7387\uff0c\u8fd9\u6837\u5728\u89c2\u5bdf\u901a\u5e26\u622a\u6b62\u9891\u7387\u548c\u963b\u5e26\u622a\u6b62\u9891\u7387\u65f6\u66f4\u52a0\u7cbe\u786e\uff0c\u8bef\u5dee\u8f83\u5c0f\u3002<a name=\"_Toc249500208\"><\/a><\/p>\n<p>&nbsp;<\/p>\n<p><strong>5 <\/strong><strong>\u8bfe\u7a0b\u8bbe\u8ba1\u5fc3\u5f97\u4f53\u4f1a<\/strong><\/p>\n<p>\u91c7\u7528MATLAB\u8bbe\u8ba1\u6ee4\u6ce2\u5668\uff0c\u4f7f\u539f\u6765\u975e\u5e38\u7e41\u7410\u590d\u6742\u7684\u7a0b\u5e8f\u8bbe\u8ba1\u53d8\u6210\u4e86\u7b80\u5355\u7684\u51fd\u6570\u8c03\u7528\uff0c\u4e3a\u6ee4\u6ce2\u5668\u7684\u8bbe\u548c\u5b9e\u73b0\u5f00\u8f9f\u4e86\u5e7f\u9614\u7684\u5929\u5730\uff0c\u5c24\u5176\u662fMATLAB\u5de5\u5177\u7bb1\u4f7f\u5404\u4e2a\u9886\u57df\u7684\u7814\u7a76\u4eba\u5458\u53ef\u4ee5\u76f4\u89c2\u65b9\u4fbf\u5730\u8fdb\u884c\u79d1\u5b66\u7814\u7a76\u4e0e\u5de5\u7a0b\u5e94\u7528\u3002\u5176\u4e2d\u7684\u4fe1\u53f7\u5904\u7406\u5de5\u5177\u7bb1\u3001\u56fe\u50cf\u5904\u7406\u5de5\u5177\u7bb1\u3001\u5c0f\u6ce2\u5de5\u5177\u7bb1\u7b49\u66f4\u662f\u4e3a\u6570\u5b57\u6ee4\u6ce2\u7814\u7a76\u7684\u84ec\u52c3\u53d1\u5c55\u63d0\u4f9b\u4e86\u53ef\u80fd\u3002MATLAB \u4fe1\u53f7\u5904\u7406\u5de5\u5177\u7bb1\u4e3a\u6ee4\u6ce2\u5668\u8bbe\u8ba1\u53ca\u5206\u6790\u63d0\u4f9b\u4e86\u975e\u5e38\u4f18\u79c0\u7684\u8f85\u52a9\u8bbe\u8ba1\u5de5\u5177, \u5728\u8bbe\u8ba1\u6570\u5b57\u6ee4\u6ce2\u5668\u65f6, \u5584\u4e8e\u5e94\u7528MATLAB\u8fdb\u884c\u8f85\u52a9\u8bbe\u8ba1, \u80fd\u591f\u5927\u5927\u63d0\u9ad8\u8bbe\u8ba1\u6548\u7387\u3002\u4e24\u5468\u7684\u8bfe\u7a0b\u8bbe\u8ba1\u8ba9\u6211\u5bf9MATLAB\u8f6f\u4ef6\u7684\u4f7f\u7528\u66f4\u52a0\u7684\u719f\u7ec3\uff0c\u5bf9\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4\u6ce2\u5668\u539f\u7406\u6709\u4e86\u66f4\u6df1\u523b\u7684\u8ba4\u8bc6\u3002<\/p>\n<p>&nbsp;<\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>6 <\/strong><strong>\u53c2\u8003\u6587\u732e<\/strong><\/p>\n<p>[1] \u7a0b\u4f69\u9752\uff0e\u6570\u5b57\u4fe1\u53f7\u5904\u7406\u6559\u7a0b\uff3bM\uff3d\uff0e\u5317\u4eac\uff1a\u6e05\u534e\u5927\u5b66\u51fa\u7248\u793e\uff0c2002<\/p>\n<p>[2] \u859b\u5e74\u559c\u4e3b\u7f16\uff0eMATLAB \u5728\u6570\u5b57\u4fe1\u53f7\u5904\u7406\u4e2d\u7684\u5e94\u7528[M]\uff0e\u5317\u4eac\uff1a\u6e05\u534e\u5927\u5b66\u51fa\u7248\u793e\uff0c2002<\/p>\n<p>[3]\u00a0 \u7ef4\u7eb3\u2022K\u2022\u6069\u683c\u5c14\uff0c\u7ea6\u7ff0\u2022G\u2022\u666e\u7f57\u514b\u65af.\u300a\u6570\u5b57\u4fe1\u53f7\u5904\u7406\u300b[M].\u897f\u5b89\u4ea4\u901a\u5927\u5b66\u51fa\u7248\u793e\uff0c2002<\/p>\n<p>[4] \u8463\u957f\u8679\u7b49. MATLAB\u4fe1\u53f7\u5904\u7406\u4e0e\u5e94\u7528[M].\u5317\u4eac\uff1a\u56fd\u9632\u5de5\u4e1a\u51fa\u7248\u793e\uff0c2005<br \/>\n[5] [\u7f8e] M.H.\u6d77\u56e0\u65af \u8457\uff0c\u5f20\u5efa\u534e\u7b49 \u8bd1.\u6570\u5b57\u4fe1\u53f7\u5904\u7406[M].\u5317\u4eac\uff1a\u79d1\u5b66\u51fa\u7248\u793e\uff0c2002<br \/>\n[6] \u5f20\u845b\u7965\uff0c\u674e \u5a1c. MATLAB\u4eff\u771f\u6280\u672f\u4e0e\u5e94\u7528[M].\u5317\u4eac\uff1a\u6e05\u534e\u5927\u5b66\u51fa\u7248\u793e\uff0c2007<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>\u9644\u5f55\u4e00: \u6e90\u7a0b\u5e8f\u8bbe\u8ba1\u6e05\u5355<\/p>\n<p>\u539f\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7\u7684\u91c7\u96c6\u53ca\u52a0\u566a\uff1a<\/p>\n<p>[x,fs,bits]=wavread(&#8216;D:\\MATLAB7\\work\\xiaomiao.wav&#8217;); \u00a0% \u8f93\u5165\u53c2\u6570\u4e3a\u6587\u4ef6\u7684\u5168\u8def\u5f84\u548c\u6587\u4ef6\u540d\uff0c\u8f93\u51fa\u7684\u7b2c\u4e00\u4e2a\u53c2\u6570\u662f\u6bcf\u4e2a\u6837\u672c\u7684\u503c\uff0cfs\u662f\u751f\u6210\u8be5\u6ce2\u5f62\u6587\u4ef6\u65f6\u7684\u91c7\u6837\u7387\uff0cbits\u662f\u6ce2\u5f62\u6587\u4ef6\u6bcf\u6837\u672c\u7684\u7f16\u7801\u4f4d\u6570\u3002<\/p>\n<p>sound(x,fs,bits);\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u6309\u6307\u5b9a\u7684\u91c7\u6837\u7387\u548c\u6bcf\u6837\u672c\u7f16\u7801\u4f4d\u6570\u56de\u653e<\/p>\n<p>N=length(x);\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u4fe1\u53f7x\u7684\u957f\u5ea6<\/p>\n<p>fn=2200;\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u5355\u9891\u566a\u58f0\u9891\u7387\uff0c\u6b64\u53c2\u6570\u53ef\u6539<\/p>\n<p>t=0:1\/fs:(N-1)\/fs;\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u65f6\u95f4\u8303\u56f4\uff0c\u6837\u672c\u6570\u9664\u4ee5\u91c7\u6837\u9891\u7387<\/p>\n<p>x=x(:,1)&#8217;; y=x+sin(fn*2*pi*t);<\/p>\n<p>sound(y,fs,bits);\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u5e94\u8be5\u53ef\u4ee5\u660e\u663e\u542c\u51fa\u6709\u5c16\u9510\u7684\u5355\u9891\u5578\u53eb\u58f0<\/p>\n<p>X=abs(fft(x));\u00a0 Y=abs(fft(y));\u00a0 \u00a0\u00a0% \u5bf9\u539f\u59cb\u4fe1\u53f7\u548c\u52a0\u566a\u4fe1\u53f7\u8fdb\u884cfft\u53d8\u6362,\u53d6\u5e45\u5ea6\u8c31<\/p>\n<p>X=X(1:N\/2); Y=Y(1:N\/2); \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u622a\u53d6\u524d\u534a\u90e8\u5206<\/p>\n<p>Warning: Integer operands are required for colon operator when used as index.<\/p>\n<p>Warning: Integer operands are required for colon operator when used as index.<\/p>\n<p>deltaf=fs\/N;\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u9891\u8c31\u7684\u8c31\u7ebf\u95f4\u9694<\/p>\n<p>f=0:deltaf:fs\/2-deltaf;\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u9891\u8c31\u9891\u7387\u8303\u56f4<\/p>\n<p>subplot(2,2,1);plot(t,x);xlabel(&#8216;\u65f6\u95f4(\u5355\u4f4d:s)&#8217;);ylabel(&#8216;\u5e45\u5ea6&#8217;);title(&#8216;\u539f\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7&#8217;);grid<\/p>\n<p>subplot(2,2,2);plot(f,X);xlabel(&#8216;\u9891\u7387(\u5355\u4f4d:Hz)&#8217;);ylabel(&#8216;\u5e45\u5ea6\u8c31&#8217;);title(&#8216;\u539f\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7\u5e45\u5ea6\u8c31\u56fe&#8217;); axis([0,6*10^3,0,6000]);grid<\/p>\n<p>subplot(2,2,3);plot(t,y);xlabel(&#8216;\u65f6\u95f4(\u5355\u4f4d:s)&#8217;);ylabel(&#8216;\u5e45\u5ea6&#8217;);title(&#8216;\u52a0\u566a\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7&#8217;);grid<\/p>\n<p>subplot(2,2,4);plot(f,Y);xlabel(&#8216;\u9891\u7387(\u5355\u4f4d:Hz)&#8217;);ylabel(&#8216;\u5e45\u5ea6\u8c31&#8217;);title(&#8216;\u52a0\u566a\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7\u5e45\u5ea6\u8c31\u56fe&#8217;); axis([0,6*10^3,0,6000]);grid<\/p>\n<p>&nbsp;<\/p>\n<p>\u4f7f\u7528\u53cc\u7ebf\u6027\u53d8\u6362\u6cd5\u8bbe\u8ba1\u5207\u6bd4\u96ea\u592bI\u578b\u6ee4\u6ce2\u5668\uff1a<\/p>\n<p>fp=fn-200;fc=fn-50;\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0%\u5b9a\u4e49\u901a\u5e26\u548c\u963b\u5e26\u622a\u6b62\u9891\u7387<\/p>\n<p>Rp=1;As=35;\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0% \u5b9a\u4e49\u901a\u5e26\u6ce2\u7eb9\u548c\u963b\u5e26\u8870\u51cf<\/p>\n<p>wp=fp\/fs*2*pi; ws=fc\/fs*2*pi;\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0%\u8ba1\u7b97\u5bf9\u5e94\u7684\u6570\u5b57\u9891\u7387<\/p>\n<p>T=1;Fs = 1\/T; \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0%\u5b9a\u4e49\u91c7\u6837\u95f4\u9694<\/p>\n<p>Omegap=(2\/T)*tan(wp\/2);<\/p>\n<p>Omegas=(2\/T)*tan(ws\/2);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0%\u622a\u6b62\u9891\u7387\u9884\u7578\u53d8<\/p>\n<p>[cs,ds] = afd_chb1(Omegap,Omegas,Rp,As);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0%\u9009\u62e9\u6ee4\u6ce2\u5668\u6700\u5c0f\u9636\u6570<\/p>\n<p>Warning: Function call afd_chb1 invokes inexact match d:\\MATLAB7\\work\\AFD_CHB1.M.<\/p>\n<p>*** \u5207\u6bd4\u96ea\u592b-1 \u6ee4\u6ce2\u5668\u9636\u6b21 = 14<\/p>\n<p>Warning: Function call u_chb1ap invokes inexact match d:\\MATLAB7\\work\\U_CHB1AP.M.<\/p>\n<p>&gt; In AFD_CHB1 at 29<\/p>\n<p>[b,a] = bilinear(cs,ds,Fs);[C,B,A] = dir2cas(b,a)\u00a0\u00a0\u00a0\u00a0\u00a0 %\u53cc\u7ebf\u6027\u53d8\u6362\u6cd5\u5b9e\u73b0\u6a21\u62df\u6ee4\u6ce2\u5668\u5230<\/p>\n<p>\u6570\u5b57\u6ee4\u6ce2\u5668\u7684\u8f6c\u6362<\/p>\n<p>Warning: Function call dir2cas invokes inexact match d:\\MATLAB7\\work\\DIR2CAS.M.<\/p>\n<p>C =<\/p>\n<p>3.3307e-016<\/p>\n<p>B =<\/p>\n<p>1.0000\u00a0\u00a0 -0.0321\u00a0\u00a0\u00a0 0.4021<\/p>\n<p>1.0000\u00a0\u00a0 -0.2091\u00a0\u00a0\u00a0 0.0238<\/p>\n<p>1.0000\u00a0\u00a0 -0.2206\u00a0\u00a0\u00a0 5.8342<\/p>\n<p>1.0000\u00a0\u00a0 -0.3400\u00a0\u00a0\u00a0 0.1487<\/p>\n<p>1.0000\u00a0\u00a0 -0.5438\u00a0\u00a0\u00a0 0.7109<\/p>\n<p>1.0000\u00a0\u00a0 -2.1153\u00a0\u00a0\u00a0 8.5100<\/p>\n<p>1.0000\u00a0 -12.5391\u00a0 364.1406<\/p>\n<p>A =<\/p>\n<p>1.0000\u00a0\u00a0 -1.9050\u00a0\u00a0\u00a0 0.9776<\/p>\n<p>1.0000\u00a0\u00a0 -1.9116\u00a0\u00a0\u00a0 0.9540<\/p>\n<p>1.0000\u00a0\u00a0 -1.9147\u00a0\u00a0\u00a0 0.9950<\/p>\n<p>1.0000\u00a0\u00a0 -1.9185\u00a0\u00a0\u00a0 0.9754<\/p>\n<p>1.0000\u00a0\u00a0 -1.9315\u00a0\u00a0\u00a0 0.9425<\/p>\n<p>1.0000\u00a0\u00a0 -1.9354\u00a0\u00a0\u00a0 0.9570<\/p>\n<p>1.0000\u00a0\u00a0 -1.9430\u00a0\u00a0\u00a0 0.9444<\/p>\n<p>&nbsp;<\/p>\n<p>[db,mag,pha,grd,w]=freqz_m(b,a);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0%\u7ed8\u5236\u6570\u5b57\u6ee4\u6ce2\u5668\u9891\u7387\u54cd\u5e94\u5e45\u5ea6\u56fe<\/p>\n<p>Warning: Function call freqz_m invokes inexact match d:\\MATLAB7\\work\\FREQZ_M.M. delta=[1,zeros(1,99)];ha=filter(b,a,delta);<\/p>\n<p>figure<\/p>\n<p>Subplot(221);plot(w\/pi,db); title(&#8216;\u5207\u6bd4\u96ea\u592bI \u6ee4\u6ce2\u5668\u5e45\u5ea6(dB)&#8217;);<\/p>\n<p>xlabel(&#8216;w&#8217;);ylabel(&#8216;dB&#8217;);axis([0,1,-150,10]);grid<\/p>\n<p>Subplot(222);plot(w\/pi,mag);title(&#8216;\u5207\u6bd4\u96ea\u592bI\u6ee4\u6ce2\u5668\u5e45\u5ea6\u54cd\u5e94&#8217;);xlabel(&#8216;w&#8217;);ylabel(&#8216;\u5e45\u503c |H|&#8217;); axis([0,1,0,1]);grid<\/p>\n<p>Subplot(223);plot(w\/pi,pha);title(&#8216;\u5207\u6bd4\u96ea\u592bI \u6ee4\u6ce2\u5668\u76f8\u4f4d\u54cd\u5e94&#8217;); xlabel(&#8216;w&#8217;);ylabel(&#8216;\u76f8\u4f4d\uff08\u5355\u4f4d\uff1a\u03c0 \uff09&#8217;);axis([0,1,-4,4]);grid<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>\u5bf9\u52a0\u566a\u4fe1\u53f7\u8fdb\u884c\u6ee4\u6ce2\u5904\u7406\u5e76\u753b\u51fa\u52a0\u566a\u524d\u540e\u7684\u4fe1\u53f7\u65f6\u57df\u548c\u9891\u8c31\uff1a<\/p>\n<p>y_fil=filter(b,a,y);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 % \u7528\u8bbe\u8ba1\u597d\u7684\u6ee4\u6ce2\u5668\u5bf9y\u8fdb\u884c\u6ee4\u6ce2<\/p>\n<p>Y_fil=abs(fft(y_fil));Y_fil=Y_fil(1:N\/2); \u00a0\u00a0\u00a0\u00a0\u00a0% \u8ba1\u7b97\u9891\u8c31\u53d6\u524d\u4e00\u534a<\/p>\n<p>Warning: Integer operands are required for colon operator when used as index.<\/p>\n<p>figure<\/p>\n<p>subplot(3,2,1);plot(t,x);xlabel(&#8216;\u65f6\u95f4(\u5355\u4f4d:s)&#8217;);ylabel(&#8216;\u5e45\u5ea6&#8217;);title(&#8216;\u539f\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7&#8217;);grid<\/p>\n<p>subplot(3,2,2);plot(f,X);xlabel(&#8216;\u9891\u7387(\u5355\u4f4d:Hz)&#8217;);ylabel(&#8216;\u5e45\u5ea6\u8c31&#8217;);title(&#8216;\u539f\u59cb\u53cc\u97f3\u9891\u4fe1\u53f7\u5e45\u5ea6\u8c31\u56fe&#8217;);grid<\/p>\n<p>axis([0,6*10^3,0,6000])<\/p>\n<p>subplot(3,2,3);plot(t,y);xlabel(&#8216;\u65f6\u95f4(\u5355\u4f4d:s)&#8217;);ylabel(&#8216;\u5e45\u5ea6&#8217;);title(&#8216;\u52a0\u566a\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7&#8217;);grid<\/p>\n<p>subplot(3,2,4);plot(f,Y);xlabel(&#8216;\u9891\u7387(\u5355\u4f4d:Hz)&#8217;);ylabel(&#8216;\u5e45\u5ea6\u8c31&#8217;);title(&#8216;\u52a0\u566a\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7\u5e45\u5ea6\u8c31\u56fe&#8217;);grid<\/p>\n<p>axis([0,6*10^3,0,6000])<\/p>\n<p>subplot(3,2,5);plot(t,y_fil);xlabel(&#8216;\u65f6\u95f4(\u5355\u4f4d:s)&#8217;);ylabel(&#8216;\u5e45\u5ea6&#8217;);title(&#8216;\u6ee4\u6ce2\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7&#8217;);grid<\/p>\n<p>axis([0,6,-1,1])<\/p>\n<p>subplot(3,2,6);plot(f,Y_fil);xlabel(&#8216;\u9891\u7387(\u5355\u4f4d:Hz)&#8217;);ylabel(&#8216;\u5e45\u5ea6\u8c31&#8217;);title(&#8216;\u6ee4\u6ce2\u540e\u7684\u53cc\u97f3\u9891\u4fe1\u53f7\u5e45\u5ea6\u8c31\u56fe&#8217;);grid<\/p>\n<p>axis([0,6*10^3,0,6000])<\/p>\n<p>&nbsp;<\/p>\n<p>\u9644\u5f55\u4e8c\uff1aafd_chb1\u51fd\u6570<\/p>\n<p>function [b,a] = afd_chb1(Wp,Ws,Rp,As);<\/p>\n<p>% \u5207\u6bd4\u96ea\u592b-1\u578b\u6a21\u62df\u4f4e\u901a\u6ee4\u6ce2\u5668\u8bbe\u8ba1<\/p>\n<p>% &#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211;<\/p>\n<p>% [b,a] = afd_chb1(Wp,Ws,Rp,As);<\/p>\n<p>%\u00a0 b = Ha(s) \u5206\u5b50\u7684\u7cfb\u6570<\/p>\n<p>%\u00a0 a = Ha(s) \u5206\u6bcd\u7684\u7cfb\u6570<\/p>\n<p>% Wp = \u4ee5\u5f27\u5ea6\/\u79d2\u4e3a\u5355\u4f4d\u7684\u901a\u5e26\u8fb9\u7f18\u9891\u7387; Wp &gt; 0<\/p>\n<p>% Ws = \u4ee5\u5f27\u5ea6\/\u79d2\u4e3a\u5355\u4f4d\u7684\u963b\u5e26\u8fb9\u7f18\u9891\u7387; Ws &gt; Wp &gt; 0<\/p>\n<p>% Rp = \u901a\u5e26\u4e2d\u7684\u632f\u5e45\u6ce2\u52a8\u7684+dB\u6570; (Rp &gt; 0)<\/p>\n<p>% As = \u963b\u5e26\u8870\u51cf\u7684+dB\u6570; (As &gt; 0)<\/p>\n<p>%<\/p>\n<p>if Wp &lt;= 0<\/p>\n<p>error(&#8216;\u901a\u5e26\u8fb9\u7f18\u5fc5\u987b\u5927\u4e8e 0&#8217;)<\/p>\n<p>end<\/p>\n<p>if Ws &lt;= Wp<\/p>\n<p>error(&#8216;\u963b\u5e26\u8fb9\u7f18\u5fc5\u987b\u5927\u4e8e\u901a\u5e26\u8fb9\u7f18&#8217;)<\/p>\n<p>end<\/p>\n<p>if (Rp &lt;= 0) | (As &lt; 0)<\/p>\n<p>error(&#8216;\u901a\u5e26\u6ce2\u52a8\u6216\u963b\u5e26\u8870\u51cf\u5fc5\u987b\u5927\u4e8e0&#8217;)<\/p>\n<p>end<\/p>\n<p>ep = sqrt(10^(Rp\/10)-1);<\/p>\n<p>A = 10^(As\/20);<\/p>\n<p>OmegaC = Wp;<\/p>\n<p>OmegaR = Ws\/Wp;<\/p>\n<p>g = sqrt(A*A-1)\/ep;<\/p>\n<p>N = ceil(log10(g+sqrt(g*g-1))\/log10(OmegaR+sqrt(OmegaR*OmegaR-1)));<\/p>\n<p>fprintf(&#8216;\\n*** \u5207\u6bd4\u96ea\u592b-1 \u6ee4\u6ce2\u5668\u9636\u6b21 = %2.0f \\n&#8217;,N)<\/p>\n<p>[b,a]=u_chb1ap(N,Rp,OmegaC);<\/p>\n<p>&nbsp;<\/p>\n<p>\u9644\u5f55\u4e09\uff1afreqz.m.m\u51fd\u6570<\/p>\n<p>function [db,mag,pha,grd,w] = freqz_m(b,a);<\/p>\n<p>% freqz \u5b50\u7a0b\u5e8f\u7684\u6539\u8fdb\u7248\u672c<\/p>\n<p>% &#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;<\/p>\n<p>% [db,mag,pha,grd,w] = freqz_m(b,a);<\/p>\n<p>%\u00a0\u00a0 db = [0 \u5230pi\u5f27\u5ea6]\u533a\u95f4\u5185\u7684\u76f8\u5bf9\u632f\u5e45(db)<\/p>\n<p>%\u00a0 mag = [0 \u5230pi\u5f27\u5ea6]\u533a\u95f4\u5185\u7684\u7edd\u5bf9\u632f\u5e45<\/p>\n<p>%\u00a0 pha = [0 \u5230pi\u5f27\u5ea6]\u533a\u95f4\u5185\u7684\u76f8\u4f4d\u54cd\u5e94<\/p>\n<p>%\u00a0 grd = [0 \u5230pi\u5f27\u5ea6]\u533a\u95f4\u5185\u7684\u7fa4\u8fdf\u5ef6<\/p>\n<p>%\u00a0\u00a0\u00a0 w =\u00a0 [0 \u5230pi\u5f27\u5ea6]\u533a\u95f4\u5185\u7684501\u4e2a\u9891\u7387\u6837\u672c\u5411\u91cf<\/p>\n<p>%\u00a0\u00a0\u00a0 b = Ha(z)\u7684\u5206\u5b50\u591a\u9879\u5f0f\u7cfb\u6570(\u5bf9FIR b=h)<\/p>\n<p>%\u00a0\u00a0\u00a0 a = Ha(z)\u7684\u5206\u6bcd\u591a\u9879\u5f0f\u7cfb\u6570(\u5bf9 FIR: a=[1])<\/p>\n<p>%<\/p>\n<p>[H,w] = freqz(b,a,1000,&#8217;whole&#8217;);<\/p>\n<p>H = (H(1:1:501))&#8217;; w = (w(1:1:501))&#8217;;<\/p>\n<p>mag = abs(H);<\/p>\n<p>db = 20*log10((mag+eps)\/max(mag));<\/p>\n<p>pha = angle(H);<\/p>\n<p>%\u00a0 pha = unwrap(angle(H));<\/p>\n<p>grd = grpdelay(b,a,w);<\/p>\n<p>%\u00a0 grd = diff(pha);<\/p>\n<p>%\u00a0 grd = [grd(1) grd];<\/p>\n<p>%\u00a0 grd = [0 grd(1:1:500); grd; grd(2:1:501) 0];<\/p>\n<p>%\u00a0 grd = median(grd)*500\/pi;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; \u8bed\u97f3\u4fe1\u53f7\u6ee4\u6ce2\u53bb\u566a \u2014\u2014\u7a97\u51fd\u6570\u6cd5\u8bbe\u8ba1FIR\u4f4e\u901a\u6ee4&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_kadence_starter_templates_imported_post":false,"footnotes":""},"categories":[11,12],"tags":[15,17,24],"class_list":["post-819","post","type-post","status-publish","format-standard","hentry","category-11","category-12","tag-learn","tag-17","tag-24"],"_links":{"self":[{"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/posts\/819","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/comments?post=819"}],"version-history":[{"count":0,"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/posts\/819\/revisions"}],"wp:attachment":[{"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/media?parent=819"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/categories?post=819"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/growlove.cn\/index.php\/wp-json\/wp\/v2\/tags?post=819"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}