本设计是一个数字调频收音机，调频就是频率调制，所谓频率调制就是原来等幅恒频的高频信号的频率，随着调制信号（音频信号）的幅度变化而变化，调频收音机（FM Radio）就是接收这些频率调制的无线电信号，经过解调还原成原信号的电子设备。FM Radio电路一般主要由接收天线、振荡器、混频器、AGC（自动增益控制）、中频放大器、中频限幅器、中频滤波器、鉴频器、低频静噪电路、搜索调谐电路、信号检测电路及频率锁定环路、音频输出电路等组成。本设计就是用单片机控制集成了上述所有FM功能的专用芯片，设计一个数字FM收音机系统。

-This design is a digital FM radio, FM is frequency modulation, frequency modulation is the original so-called constant frequency amplitude high-frequency signal frequency, with the modulation signal (audio signal) the magnitude of change, FM Radio (FM Radio) is frequency modulation radio receiving these signals, the demodulated signal to restore to the original electronic equipment. FM Radio is generally mainly by the receiving antenna circuit, oscillators, mixers, AGC (automatic gain control), IF amplifier, IF limiter, IF filter, frequency discriminator, frequency squelch circuit, search tuning circuit, signal detection and frequency locked loop circuit, the audio output circuit. This design is integrated with MCU control all of the above FM function ASIC design of a digital FM radio system.