实验二连续时间系统的频率响应

1、-. z.实验二连续时间系统的频率响应39022622 龚小川一实验目的：1. 进一步加深对连续时间系统频率响应理解；2掌握借助计算机计算任意连续时间系统频率响应的方法。二实验原理1.本实验的根本内容就是将系统函数的幅频特性曲线以及相频特性曲线给画出来。而系统函数,令,则即1计算所有零点模之积及极点模之积，两者之商即为的幅度；2计算所有零点相角之和及极点相角之和，两者之差即为的相角。2.通过零极点图通过几何的方法来计算，而且通过零极点图可以迅速地判断系统的滤波特性。通过零极点图进展计算的方法是：1在S 平面上标出系统的零极点位置；2选择S 平面的坐标原点为起始点，沿虚轴向上移动，计算此时各极点

2、和零点与该点的膜和夹角；3将所有零点的模相乘，再除以各极点的模，得到对应频率处的幅频特性的值；4将所有零点的幅角相加，减去各极点的幅角，得到对应频率处的相角。三实验流程图jm,否是输出temp1,即为零点模之积令j=0,temp1=1in,否是输出temp2,即为极点模之积令i=0,temp2=1输出temp1/temp2,极为H(s)之幅度jm 否是输出temp1,即为零点相角之和令j=0,temp1=0in否是输出temp2,即为极点相角之和令i=0,temp2=0输出temp1-temp2,极为H(s)之相角四实验代码#include stdio.h#include math.h#inc

3、lude graphics.hfloat atannew(float t1,float t2);int main()float z102,p102,out1003,f50; int a,iout;int i,itemp,k,ktemp,j,m,n;float w,temp1,temp2,prew,pretemp1,pretemp2,ptemp,h,fout;int gdriver,gmode=0;char s10; gdriver=0; /*/ for(i=0;i=10;i+) a=scanf(%f %fj,&zi0,&zi1); if(a!=0); elsefflush(stdin);/*清

4、空输入缓冲区,使得第二个scanf不被忽略*/ for(k=0;k=10;k+) a=scanf(%f %fj,&pk0,&pk1); if(a!=0); else break;break;/*/initgraph(&gdriver,&gmode, e:tcbgi);setbkcolor(10); setcolor(4); setlinestyle(1,0,1); rectangle(50,20,600,420); for(ptemp=20;ptemp=420;ptemp=ptemp+50) line(50,ptemp,600,ptemp); for(ptemp=50;ptemp=600;pt

5、emp=ptemp+50) line(ptemp,20,ptemp,420); setlinestyle(0,0,1); setcolor(1); line(200,20,200,420); line(50,420,600,420); line(200,20,190,30); line(200,20,210,30); outte*t*y(210,30,A); line(600,420,590,410); line(600,420,590,430); outte*t*y(600,430,w); for(iout=0;iout=5;iout+) sprintf(s,%d,iout); outte*

6、t*y(iout*50+200,430,s); for(fout=1.0;fout=8;fout=fout+1) sprintf(s,%.1f,fout/10); outte*t*y(170,420-fout*50,s); setcolor(4);/*printf(w 幅度相角n);*/for(w=0,j=0;w=5.0;j+) temp1=1; for(itemp=0;itemp=i-1;itemp+)temp1=temp1*sqrt(zitemp0*zitemp0+(zitemp1-w)*(zitemp1-w);for(ktemp=0;ktemp0) line(prew*40+200,42

7、0-pretemp1*500,w*40+200,420-temp1*500); prew=w; pretemp1=temp1; w=w+0.1; for(m=0;moutm+11) break; printf(%.4f,%f,outm1,outm0); line(100,420-outm1/sqrt(2)*500,500,420-outm1/sqrt(2)*500); getch(); closegraph(); initgraph(&gdriver,&gmode, e:tcbgi); setbkcolor(10); setcolor(4); setlinestyle(1,0,1); rect

8、angle(50,20,600,420); for(ptemp=20;ptemp=420;ptemp=ptemp+50) line(50,ptemp,600,ptemp); for(ptemp=50;ptemp=600;ptemp=ptemp+50) line(ptemp,20,ptemp,420); for(w=0,j=0;w=5;j+) temp2=0;for(ktemp=0;ktemp=k-1;ktemp+)temp2=temp2-atannew(-pktemp0,w-pktemp1);for(itemp=0;itemp=180) temp2=temp2-360;else if(temp

9、20)line(prew*50+200,180+pretemp2,w*50+200,180+temp2);prew=w;pretemp2=temp2;w=w+0.1;getch(); closegraph(); for(j=0;j=50;j+) printf(%.2f,%.4f,%.2f*,outj0,outj1,outj2); printf(nn); for(n=0,j=0;n=50;n+) fn=fabs(outm1/sqrt(2)-outn1); for(n=0,h=f0,j=0;nfn) h=fn; j=n; printf(Fl=%.1fn,outj0); for(n=m,h=f0,j

10、=0;nfn) h=fn; j=n; printf(Fh=%.1f,outj0); getch(); return 0;float atannew(float t1,float t2)if(t10&t20)return atan(t2/t1)/3.14*180;else if(t10&t20)return 180+atan(t2/t1)/3.14*180;else if(t10)return 180+atan(t2/t1)/3.14*180;else if(t10&t20) return 90;else if(t1=0&t20&t2=0) return 180;else if(t10&t2=0

11、) return -180; 五实验数据及所绘图形零点z1=0;极点 p1=-1-j,p2=-1+jw|H(jw)|(jw)w|H(jw)|(jw)0.10.04999984.26712.60.368813-42.47360.20.0999878.471152.70.357173-44.41370.30.14984872.565952.80.34606-46.20520.40.19936366.506332.90.335472-47.86360.50.24806960.2595530.325396-49.40230.60.29525553.810753.10.315814-50.83340.7

12、0.33994647.168263.20.306705-52.16740.80.3809740.36753.30.298046-53.41350.90.41709233.471593.40.289812-54.579910.44721426.5673.50.281981-55.67391.10.4705819.75423.60.274528-56.70191.20.48692113.134983.70.267431-57.66961.30.4964836.7998163.80.26067-58.58221.40.4999490.818513.90.254222-59.44421.50.4982

13、73-4.76440.248069-60.25961.60.492515-9.926984.10.242194-61.03211.70.483703-14.674.20.23658-61.7651.80.472742-19.00744.30.231209-62.46131.90.460383-22.96334.40.22607-63.123620.447214-26.5674.50.221146-63.75452.10.433676-29.84984.60.216427-64.3562.20.420092-32.84284.70.211899-64.93012.30.406687-35.575

14、64.80.207553-65.47892.40.393614-38.07564.90.203377-66.0037幅频特性曲线：横线3dB线。Fl=0.7,Fh=2.7.零点z1=2+1.5j,z2=2-1.5j;极点 p1=-0.5-0.7j,p2=-0.5+0.7j,p3=-2.5-2j,p4=-2.5+2j0.0 0.823995 197.606976 2.50.125927 -30.168391 0.1 0.827748 188.753095 2.60.117968 -34.228230 0.2 0.838357 179.054798 2.70.110810 -38.136293 0

15、.3 0.853583 168.286633 2.80.104336 -41.899355 0.4 0.868832 156.232443 2.90.098449 -45.523151 0.5 0.876442 142.775678 30.093071 -49.012709 0.6 0.866588 128.047702 3.10.088137 -52.372588 0.7 0.830997 112.553808 3.20.083592 -55.607056 0.8 0.769583 97.107608 3.30.079392 -58.720204 0.9 0.691002 82.523335

16、 3.40.075499 -61.716031 1.0 0.607503 69.308133 3.50.071880 -64.598482 1.1 0.528568 57.596395 3.60.068509 -67.371483 1.2 0.458892 47.275738 3.70.065362 -70.038943 1.3 0.399643 38.134987 3.80.062418 -72.604758 1.4 0.350120 29.954729 3.90.059661 -75.072798 1.5 0.308962 22.544718 40.057073 -77.446896 1.6 0.274727 15.752411 4.10.054642 -79.730837 1.7 0.246120 9.459839 4.20.052356 -81.928340 1.8 0.222060 3.577246 4.30.050202 -84.043045 1.9 0.201673 -1.963215 4.40.048172 -86.078505 2.0