我要做的是让a*b的值做反傅立叶转 a在频域上的范围是3*10^17/1520~3*10^17/1570 而a取样1024个点 於是就在刚刚提到频域上这段范围除以1024 等於是平均两个点的频率间格(应该就是取样频率?) 不过这边会出现一个问题 取样频率没有大於最高频率 但是如果要让取样频率大於最高频率 取的点必须很少 那精确度就不够了 要怎麽解决这个问题呢 以下附上我的成式码 请大家帮帮忙 这个做不出来我可能就没办法把毕业了 拜托大家了 (不好意思a值个数太多了 有1024个值 这部分大家可快速跳过) %%取样值 a=[0.4146*1,0.4146*2,0.4146*3,0.4146*4,0.4146*5,0.4146*6,0.4146*7,0.4146*8,0.4146*9,0.4146*10,0.4146*11,0.4146*12,0.4146*13,0.4146*14,0.4146*15,0.4146*16,0.4146*17,0.4146*18,0.4146*19,0.4146*20,0.4146*21,0.4146*22,0.4146*23,0.4146*24,0.4146*25,0.4146*26,0.4146*27,0.4146*28,0.4146*29,0.4146*30,0.4146*31,0.4146*32,0.4146*33,0.4146*34,0.4146*35,0.4146*36,0.4146*37,0.4146*38,0.4146*39,0.4146*40,0.4146*41,0.4146*42,0.4146*43,0.4146*44,0.4146*45,0.4146*46,0.4146*47,0.4146*48,0.4146*49,0.4146*50,0.4146*51,0.4146 *52,0.4146*53,0.4146*54,0.4146*55,0.4146*56,0.4146*57,0.4146*58,0.4146*59,0.4146*60,0.4146*61,0.4146*62,0.4146*63,0.4146*64,0.4146*65,0.4146*66,0.4146*67,0.4146*68,0.4146*69,0.4146*70,0.4146*71,0.4146*72,0.4146*73,0.4146*74,0.4146*75,0.4146*76,0.4146*77,0.4146*78,0.4146*79,0.4146*80,0.4146*81,0.4146*82,0.4146*83,0.4146*84,0.4146*85,0.4146*86,0.4146*87,0.4146*88,0.4146*89,0.4146*90,0.4146*91,0.4146*92,0.4146*93,0.4146*94,0.4146*95,0.4146*96,0.4146*97,0.4146*98,0.4146*99,0.4146*100,0.4146*101,0.4146*102,0.4 146*103,0.4146*104,0.4146*105,0.4146*106,0.4146*107,0.4146*108,0.4146*109,0.4146*110,0.4146*111,0.4146*112,0.4146*113,0.4146*114,0.4146*115,0.4146*116,0.4146*117,0.4146*118,0.4146*119,0.4146*120,0.4146*121,0.4146*122,0.4146*123,0.4146*124,0.4146*125,0.4146*126,0.4146*127,0.4146*128,0.4146*129,0.4146*130,0.4146*131,0.4146*132,0.4146*133,0.4146*134,0.4146*135,0.4146*136,0.4146*137,0.4146*138,0.4146*139,0.4146*140,0.4146*141,0.4146*142,0.4146*143,0.4146*144,0.4146*145,0.4146*146,0.4146*147,0.4146*148,0.4146* 149,0.4146*150,0.4146*151,0.4146*152,0.4146*153,0.4146*154,0.4146*155,0.4146*156,0.4146*157,0.4146*158,0.4146*159,0.4146*160,0.4146*161,0.4146*162,0.4146*163,0.4146*164,0.4146*165,0.4146*166,0.4146*167,0.4146*168,0.4146*169,0.4146*170,0.4146*171,0.4146*172,0.4146*173,0.4146*174,0.4146*175,0.4146*176,0.4146*177,0.4146*178,0.4146*179,0.4146*180,0.4146*181,0.4146*182,0.4146*183,0.4146*184,0.4146*185,0.4146*186,0.4146*187,0.4146*188,0.4146*189,0.4146*190,0.4146*191,0.4146*192,0.4146*193,0.4146*194,0.4146*195, 0.4146*196,0.4146*197,0.4146*198,0.4146*199,0.4146*200,0.4146*201,0.4146*202,0.4146*203,0.4146*204,0.4146*205,21+0.39*163,21+0.39*162,21+0.39*161,21+0.39*160,21+0.39*159,21+0.39*158,21+0.39*157,21+0.39*156,21+0.39*155,21+0.39*154,21+0.39*153,21+0.39*152,21+0.39*151,21+0.39*150,21+0.39*149,21+0.39*148,21+0.39*147,21+0.39*146,21+0.39*145,21+0.39*144,21+0.39*143,21+0.39*142,21+0.39*141,21+0.39*140,21+0.39*139,21+0.39*138,21+0.39*137,21+0.39*136,21+0.39*135,21+0.39*134,21+0.39*133,21+0.39*132,21+0.39*131,21+0 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,21+0.39*86,21+0.39*85,21+0.39*84,21+0.39*83,21+0.39*82,21+0.39*81,21+0.39*80,21+0.39*79,21+0.39*78,21+0.39*77,21+0.39*76,21+0.39*75,21+0.39*74,21+0.39*73,21+0.39*72,21+0.39*71,21+0.39*70,21+0.39*69,21+0.39*68,21+0.39*67,21+0.39*66,21+0.39*65,21+0.39*64,21+0.39*63,21+0.39*62,21+0.39*61,21+0.39*60,21+0.39*59,21+0.39*58,21+0.39*57,21+0.39*56,21+0.39*55,21+0.39*54,21+0.39*53,21+0.39*52,21+0.39*51,21+0.39*50,21+0.39*49,21+0.39*48,21+0.39*47,21+0.39*46,21+0.39*45,21+0.39*44,21+0.39*43,21+0.39*42,21+0.39*41,21+ 0.39*40,21+0.39*39,21+0.39*38,21+0.39*37,21+0.39*36,21+0.39*35,21+0.39*34,21+0.39*33,21+0.39*32,21+0.39*31,21+0.39*30,21+0.39*29,21+0.39*28,21+0.39*27,21+0.39*26,21+0.39*25,21+0.39*24,21+0.39*23,21+0.39*22,21+0.39*21,21+0.39*20,21+0.39*19,21+0.39*18,21+0.39*17,21+0.39*16,21+0.39*15,21+0.39*14,21+0.39*13,21+0.39*12,21+0.39*11,21+0.39*10,21+0.39*9,21+0.39*8,21+0.39*7,21+0.39*6,21+0.39*5,21+0.39*4,21+0.39*3,21+0.39*2,21+0.39*1,21,21+0.0294*1,21+0.0294*2,21+0.0294*3,21+0.0294*4,21+0.0294*5,21+0.0294*6,21+0.02 94*7,21+0.0294*8,21+0.0294*9,21+0.0294*10,21+0.0294*11,21+0.0294*12,21+0.0294*13,21+0.0294*14,21+0.0294*15,21+0.0294*16,21+0.0294*17,21+0.0294*18,21+0.0294*19,21+0.0294*20,21+0.0294*21,21+0.0294*22,21+0.0294*23,21+0.0294*24,21+0.0294*25,21+0.0294*26,21+0.0294*27,21+0.0294*28,21+0.0294*29,21+0.0294*30,21+0.0294*31,21+0.0294*32,21+0.0294*33,21+0.0294*34,21+0.0294*35,21+0.0294*36,21+0.0294*37,21+0.0294*38,21+0.0294*39,21+0.0294*40,21+0.0294*41,21+0.0294*42,21+0.0294*43,21+0.0294*44,21+0.0294*45,21+0.0294*46, 21+0.0294*47,21+0.0294*48,21+0.0294*49,21+0.0294*50,21+0.0294*51,21+0.0294*52,21+0.0294*53,21+0.0294*54,21+0.0294*55,21+0.0294*56,21+0.0294*57,21+0.0294*58,21+0.0294*59,21+0.0294*60,21+0.0294*61,21+0.0294*62,21+0.0294*63,21+0.0294*64,21+0.0294*65,21+0.0294*66,21+0.0294*67,21+0.0294*68,21+0.0294*69,21+0.0294*70,21+0.0294*71,21+0.0294*72,21+0.0294*73,21+0.0294*74,21+0.0294*75,21+0.0294*76,21+0.0294*77,21+0.0294*78,21+0.0294*79,21+0.0294*80,21+0.0294*81,21+0.0294*82,21+0.0294*83,21+0.0294*84,21+0.0294*85,21+ 0.0294*86,21+0.0294*87,21+0.0294*88,21+0.0294*89,21+0.0294*90,21+0.0294*91,21+0.0294*92,21+0.0294*93,21+0.0294*94,21+0.0294*95,21+0.0294*96,21+0.0294*97,21+0.0294*98,21+0.0294*99,21+0.0294*100,21+0.0294*101,21+0.0294*102,21+0.0294*103,21+0.0294*104,21+0.0294*105,21+0.0294*106,21+0.0294*107,21+0.0294*108,21+0.0294*109,21+0.0294*110,21+0.0294*111,21+0.0294*112,21+0.0294*113,21+0.0294*114,21+0.0294*115,21+0.0294*116,21+0.0294*117,21+0.0294*118,21+0.0294*119,21+0.0294*120,21+0.0294*121,21+0.0294*122,21+0.0294 *123,21+0.0294*124,21+0.0294*125,21+0.0294*126,21+0.0294*127,21+0.0294*128,21+0.0294*129,21+0.0294*130,21+0.0294*131,21+0.0294*132,21+0.0294*133,21+0.0294*134,21+0.0294*135,21+0.0294*136,21+0.0294*137,21+0.0294*138,21+0.0294*139,21+0.0294*140,21+0.0294*141,21+0.0294*142,24.17+0.098*101,24.17+0.098*100,24.17+0.098*99,24.17+0.098*98,24.17+0.098*97,24.17+0.098*96,24.17+0.098*95,24.17+0.098*94,24.17+0.098*93,24.17+0.098*92,24.17+0.098*91,24.17+0.098*90,24.17+0.098*89,24.17+0.098*88,24.17+0.098*87,24.17+0.098* 86,24.17+0.098*85,24.17+0.098*84,24.17+0.098*83,24.17+0.098*82,24.17+0.098*81,24.17+0.098*80,24.17+0.098*79,24.17+0.098*78,24.17+0.098*77,24.17+0.098*76,24.17+0.098*75,24.17+0.098*74,24.17+0.098*73,24.17+0.098*72,24.17+0.098*71,24.17+0.098*70,24.17+0.098*69,24.17+0.098*68,24.17+0.098*67,24.17+0.098*66,24.17+0.098*65,24.17+0.098*64,24.17+0.098*63,24.17+0.098*62,24.17+0.098*61,24.17+0.098*60,24.17+0.098*59,24.17+0.098*58,24.17+0.098*57,24.17+0.098*56,24.17+0.098*55,24.17+0.098*54,24.17+0.098*53,24.17+0.098* 52,24.17+0.098*51,24.17+0.098*50,24.17+0.098*49,24.17+0.098*48,24.17+0.098*47,24.17+0.098*46,24.17+0.098*45,24.17+0.098*44,24.17+0.098*43,24.17+0.098*42,24.17+0.098*41,24.17+0.098*40,24.17+0.098*39,24.17+0.098*38,24.17+0.098*37,24.17+0.098*36,24.17+0.098*35,24.17+0.098*34,24.17+0.098*33,24.17+0.098*32,24.17+0.098*31,24.17+0.098*30,24.17+0.098*29,24.17+0.098*28,24.17+0.098*27,24.17+0.098*26,24.17+0.098*25,24.17+0.098*24,24.17+0.098*23,24.17+0.098*22,24.17+0.098*21,24.17+0.098*20,24.17+0.098*19,24.17+0.098* 18,24.17+0.098*17,24.17+0.098*16,24.17+0.098*15,24.17+0.098*14,24.17+0.098*13,24.17+0.098*12,24.17+0.098*11,24.17+0.098*10,24.17+0.098*9,24.17+0.098*8,24.17+0.098*7,24.17+0.098*6,24.17+0.098*5,24.17+0.098*4,24.17+0.098*3,24.17+0.098*2,24.17+0.098*1,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24. 17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,24.17,0.0671*359,0.0671*358,0.0671*357,0.0671*356,0.0671*355,0.0671*354,0.0671*353,0.0671*352,0.0671*351,0.0671*350,0.0671*349,0.0671*348,0.0671*347,0.0671*346,0.0671*345,0.0671*344,0.0671*343,0.0671*342,0.0671*341,0.0671*340,0.0671*339,0.0671*338,0.0671*337,0.0671*336,0.0671*335,0.0671*334,0.0671*333,0.0671*332,0.0671*331,0.0671*330,0.0671*329,0.0671*328,0.0671*327,0.0671*326,0.0671*325,0.0671*324,0.0671*323,0.0671*322,0.0671*321,0.0671*320,0.0671*319,0. 0671*318,0.0671*317,0.0671*316,0.0671*315,0.0671*314,0.0671*313,0.0671*312,0.0671*311,0.0671*310,0.0671*309,0.0671*308,0.0671*307,0.0671*306,0.0671*305,0.0671*304,0.0671*303,0.0671*302,0.0671*301,0.0671*300,0.0671*299,0.0671*298,0.0671*297,0.0671*296,0.0671*295,0.0671*294,0.0671*293,0.0671*292,0.0671*291,0.0671*290,0.0671*289,0.0671*288,0.0671*287,0.0671*286,0.0671*285,0.0671*284,0.0671*283,0.0671*282,0.0671*281,0.0671*280,0.0671*279,0.0671*278,0.0671*277,0.0671*276,0.0671*275,0.0671*274,0.0671*273,0.0671 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671*179,0.0671*178,0.0671*177,0.0671*176,0.0671*175,0.0671*174,0.0671*173,0.0671*172,0.0671*171,0.0671*170,0.0671*169,0.0671*168,0.0671*167,0.0671*166,0.0671*165,0.0671*164,0.0671*163,0.0671*162,0.0671*161,0.0671*160,0.0671*159,0.0671*158,0.0671*157,0.0671*156,0.0671*155,0.0671*154,0.0671*153,0.0671*152,0.0671*151,0.0671*150,0.0671*149,0.0671*148,0.0671*147,0.0671*146,0.0671*145,0.0671*144,0.0671*143,0.0671*142,0.0671*141,0.0671*140,0.0671*139,0.0671*138,0.0671*137,0.0671*136,0.0671*135,0.0671*134,0.0671* 133,0.0671*132,0.0671*131,0.0671*130,0.0671*129,0.0671*128,0.0671*127,0.0671*126,0.0671*125,0.0671*124,0.0671*123,0.0671*122,0.0671*121,0.0671*120,0.0671*119,0.0671*118,0.0671*117,0.0671*116,0.0671*115,0.0671*114,0.0671*113,0.0671*112,0.0671*111,0.0671*110,0.0671*109,0.0671*108,0.0671*107,0.0671*106,0.0671*105,0.0671*104,0.0671*103,0.0671*102,0.0671*101,0.0671*100,0.0671*99,0.0671*98,0.0671*97,0.0671*96,0.0671*95,0.0671*94,0.0671*93,0.0671*92,0.0671*91,0.0671*90,0.0671*89,0.0671*88,0.0671*87,0.0671*86,0.0 671*85,0.0671*84,0.0671*83,0.0671*82,0.0671*81,0.0671*80,0.0671*79,0.0671*78,0.0671*77,0.0671*76,0.0671*75,0.0671*74,0.0671*73,0.0671*72,0.0671*71,0.0671*70,0.0671*69,0.0671*68,0.0671*67,0.0671*66,0.0671*65,0.0671*64,0.0671*63,0.0671*62,0.0671*61,0.0671*60,0.0671*59,0.0671*58,0.0671*57,0.0671*56,0.0671*55,0.0671*54,0.0671*53,0.0671*52,0.0671*51,0.0671*50,0.0671*49,0.0671*48,0.0671*47,0.0671*46,0.0671*45,0.0671*44,0.0671*43,0.0671*42,0.0671*41,0.0671*40,0.0671*39,0.0671*38,0.0671*37,0.0671*36,0.0671*35,0.0 671*34,0.0671*33,0.0671*32,0.0671*31,0.0671*30,0.0671*29,0.0671*28,0.0671*27,0.0671*26,0.0671*25,0.0671*24,0.0671*23,0.0671*22,0.0671*21,0.0671*20,0.0671*19,0.0671*18,0.0671*17,0.0671*16,0.0671*15,0.0671*14,0.0671*13,0.0671*12,0.0671*11,0.0671*10,0.0671*9,0.0671*8,0.0671*7,0.0671*6,0.0671*5,0.0671*4,0.0671*3,0.0671*2,0.0671*1]; %%1024个点，二的十次方，所以n等於10 n=10; %%把相位值带入e^j(phi)，等比例取成与取样的个数相同的个数 for z=1:2^(n-3) b(z)=1; b(z+2^(n-3))=-1; b(z+2^(n-2))=1; b(z+3*2^(n-3))=-1; b(z+4*2^(n-3))=1; b(z+5*2^(n-3))=-1; b(z+6*2^(n-3))=1; b(z+7*2^(n-3))=-1; end %%相乘 c=a.*b; %%取样频率为取样的两点之间之间隔 fs=(3*10^17/1520-3*10^17/1570)/2^n; %%反傅立叶转换回来之後，时间单位横轴为ps time=(-2^(n-1): 2^(n-1)-1)*10^12/fs; %%反傅立叶转换 m=ifft(c, 2^n); %%对反傅立叶转换回来的值取绝对值 y=abs(m) %%画出图形 plot(time, y, '.-'); title('Cross-correlation'); xlabel('Delay (ps)');ylabel('Power (a.u.)'); axis tight --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 140.116.92.115 ※ 编辑: hopeandhmm 来自: 140.116.92.115 (12/23 15:44) ※ 编辑: hopeandhmm 来自: 140.116.92.115 (12/23 15:45)