数字–模拟混合传输装置的设计

Design of Hybrid Transmission Device of Digital and Analog Signal

设计并制作了一套数字–模拟混合传输装置,能够实现数字信号与模拟信号单独传输和同时传输。该装置由发送机和接收机组成。发送部分采用乘法器实现模拟信号和数字信号的混合后由天线发送,接收部分采用超外差结构,通过选频网络后进行信号的分离,分离后的模拟信号直接经过检波和滤波输出,数字调制信号经过整流后解码显示。为提高带宽利用率和降低功耗,该装置采用AD9959进行FSK调制。经系统测试表明,该系统可实现模拟信号与数字信号的调制与解调,模拟信号频率范围50 Hz~10 KHz,系统在2 m内可稳定传输,频带宽度不大于25 KHz。该装置的设计为数模混合信号同传应用系统提供参考。

A hybrid transmission device of digital and analog signal was designed and implemented, which was composed of a transmitter and a receiver, and could realize separate and simultaneous transmission of digital signal and analog signal. The mixed signal based on the multiplier was sent by the antenna and received by a superheterodyne structure. The frequency selection network was used to separate the digital and analog signal. The analog signal was recovered through a detector and a filter. And the digital signal was displayed after rectifying and decoding. AD9959 for FSK modulation was used to improve bandwidth utilization and reduce power consumption. The system test shows that the system can realize modulation and demodulation of analog signal and digital signal, the frequency range of analog signal is 50 Hz~10 KHz, the system can transmit stably within 2 m, and the frequency bandwidth is not more than 25 KHz. The design of the device provides a reference for the digital-analog mixed-signal simultaneous interpretation application system.