升余弦滚降课设报考

1、移动通信设计题目：C语言实现升余弦滚降信号的匹配接收班级：08通信B姓名：谭洋学号：0815232015指导老师：陈东华一、设计原理余弦特性滚降的传输函数可表示为Ts,c(1a)JT0<©<Tststs二H(o"：1+sinmhf),22Ts0,相应的h(t)为,xsint/TShtS(1T-)二Ts-(1+0()兀©>-Ts(1y)二Tscos：-t/TSa_22/-j-21-4：t/Ts式中，a为滚降系数，用丁描述滚降程度。它定义为t/Ts：=f.：/fN其中，fN-奈奎斯特带宽，f-超出奈奎斯特带宽的扩展量当a=1时，即为升余弦频谱特性，这

2、时H®)可表示为Ts2H()=0,(1cos2<Ts2二其单位冲激响应为：hsWE二、实现程序程序如下：#include<math.h>#include<stdio.h>#definepi3.141592653589793/*本函数实现滚降特性函数，升余弦滤波器说明:fs/fd必须为整数,fd为信号采样频率,fs为滤波器采样频率当函数返回0时为正常返回，为-1时为异常返回*/intrcosine(floatfd,floatfs,floatrcs)/*函数(升余弦滤波器)返回0为正常返回,-1为异常返回*/intk,n;floatkf,nf;nf=fs/f

3、d;n=int(nf);if(nf!=n)return(-1);/*当fs/fd不是整数时异常返回*/for(k=0;k<3*n;k+)(kf=k-3*n;if(kf=-n)rcsk=0;else(nf=kf/n;kf=pi*nf;rcsk=(sin(kf)/kf)*(cos(kf/2)/(1-nf*nf);rcs6*n-k=rcsk;rcs3*n=1.0;return(0);/*当fs/fd是整数时正常返回*/voidmain()(intflag,i;staticfloatrcs200;flag=rcosine(0.6,12.0,rcs);if(flag=0)for(i=0;i<

4、200;i+)printf("%.4ft",rcsi);elseprintf("nnerror!");scanf("%d",&i);三、测试结果程序运行结果如下图：|0.00000.00026.01710.0195.丽朋-0.00911-0.1200-0.1277E.00000.04226明20.66621施099530.6M20.53226.0000-0.0363'0.1200-0.11000.00000.啊76B.01710.814B0.00000.00909,00000.00000.00000.0000加丽朋0.

5、00000.00000.00000.00000.00000.00000.00000.00000.0090虹0丽？0.00178.02140.0228-8.0196-0,0314-0.1324-0.13350.89008.14300.72890.78740.98130.95838.46340.3948-0.8666-0.0910-0.0981-0.08510.01360.01800.01198.00930-00000.000000.00000.00000.0006a.00QB0.08080.00000.00000.06000.0006S,00I3Bfl.100000.00000.00080.00

6、300.00488.82330.0227-0.0441-0.0576-0.1303-0.12250.20080.26250.84050.8872土92680.88720.32750.2625-0.1095-0A225'0.0714-0.95760.02110.022?8.88690.08480.00000.00000,WW0.00000.00000.施施0.00003.00000.00000.00000.00006.00000.00008.00000.00000.00000.0069札00930.02110.0180-0.0714-0.0851-0.1095-0.09108.327S知

7、39480.92680.95830,84050-78740.20080.1430-0.1303-0.1335-0.0441-9.03140.02330.02280.00300.00170.0000B.00000.00000-00000.08000J88000.00008.M000.00000.00000.00000.00000.08000.00000.08000.00000.01190.01460.01360.80767.0981-0.1100-0.0666-0.03630.46340.53220.98130.99530.72899.6662B.B9B00.6422-B.1324-0.1277'0,0196-0.00910.02140.019S0.00070,013020.00000.06000.03000.00000.00000.00000.00000.00008.00000.00000.施丽©.丽0。0.00000.00000.00000.0000由上图可看出程序运行结果即为升余弦