摘要
设计一个由发射机和接收机两个部分组成的简易单工无线传呼系统。发射机发送模拟、数字信号,接收机接收信息并完成响应。发射和接收天线都采用1 m长拉杆天线;35 MHz的载波信号通过锁相环(PLL)频率合成技术产生,频率稳定度高达10-5;接收部分的信号解调由收音芯片CXA1238完成,接收灵敏度高,输出信号失真小。对增加传输距离和降低波形失真进行了仔细的研究和实验,使这两项技术指标达到较高设计要求,音频输入和数据输入可自动转换,双行液晶显示,人机交互界面友好。
Design of a simplex wireless communication system with a transmitter and a receiver is realized. The transmitter sends both analog and digital signals while the receiver executes corresponding response according to the received message with the telescopic antenna of length of 1 meter. The carrier wave with frequency of 35MHz,which has a stability of up to 10^-5 ,is synthesized with PLL. The demodulation of messages of the receiver is implemented with the adaption of CXA1238 ,which can achieve a high level of sensitivity and low distortion. Through the sufficient study and experiment on extending of the transmission distance and reducing the wave distortion,the design reached a high target on the two aspects. Audio signal and digital data input can transform automotive,and the display with LCD makes the system friendly to exchange command with human.
出处
《现代电子技术》
2009年第17期7-8,12,共3页
Modern Electronics Technique
