1、1、基本原理k2、调制原理()()cos()()cos()()sin()sckkkscksckks tg tkTta g tkTtb g tkTtkcos()kkasin()kkb2、调制原理(续)输入 串/并变换载波震荡码变换 cd相加器输出 移相2p3、解调原理()()cos()cks tg tt()cos()()cos()cos()cckcs ttg ttt1()cos(2)cos()2ckkg tt1()cos()2kg t3、解调原理(续)()(sin()()cos()(sin()cckcs ttg ttt1()sin(2)sin()2ckkg tt 1()sin()2kg tstT
2、cos()IkUsin()QkU3、解调原理(续)输入 带通滤波器低通滤波抽样判决码反变换低通滤波抽样判决载波 恢复tccostcsin位定时 输出 ab移相2pcd并串变换4、功率谱密度2002)(2)(2sin2)(ssfTffTffTAfPS5、抗噪声性能()()cos()()sin()IcQcn tn ttnttcos()2IsIisEnpsin()2QsQisEnp 4p/4/41()ePfdpp()f5、抗噪声性能(续)arctan()QsInEn2000011()exp()cosexp(sin)1(cos)22ssssEEEEferfcnnnnpp0(sin()4seEPerfcnp5、抗噪声性能(续)0044pp000/40/4()1()ePfdpp 00()q000()()eePqPdpp5、抗噪声性能(续)02(sin()8seEPerfcnp22/log/log 4/2beeePPMPP021(sin()28sbEPerfcnp6、调制信号波形7、功率谱仿真8、误比特率曲线9、MATLAB程序