FM Shortwave Receiver
Abstract
This paper describes the difference between FM-AM and FM advantages. Second, the program describes the arguments and selecting the receiver, then the hardware design and adopted in the design of narrow-band FM / IF chip MC3361B complete mixing, and demodulation in place. PLL frequency synthesizer means to generate a stable local oscillator to D / A conversion method control input tuned circuit resonant frequency, in order to achieve electrical tuning. Using MCS-51 series MCU on the Serial Input PLL Frequency Synthesizer MC145L55-2 than a preset sub-band, through the D / A output control voltage. Added to the 8279 keyboard and display circuit, in order to achieve a variety of program-controlled serial E2POM search, storage and carrier radio show. Finally, through data testing and analysis, complete design requirements.
Key words:microcontroller; diode; transistor; integrated amplifier
目录
绪论 1
第1章 方案设计与论证 2
1.1协调方案设计 2
1.2单片机自动选台及搜索功能设计 3
第2章 硬件设计 4
2.1 FM(调频)/IF(中频)部分电路 4
2.2输入回路 5
2.3本振部分电路 5
2.4单片机系统设计 10
2.4.1单片机 10
2.4.2键盘和显示 10
2.4.3电台存储和调出 11
2.4.4本振频率控制 11
2.4.5谐振回路变容二极管反向偏压控制 11
第3章 程序设计 12
3.1主程序流程图 12
3.2总流程图 12
3.3程序设计 13
第4章 测试方法与数据分析 14
4.1测试仪表 14
4.2测试仪表的连接和输入输出 14
4.3性能测试 14
4.3.1最大不失真输出功率测量(负载)测试方法 14
4.3.2同频带测试方法 15
4.3.3选择性测试方法 15
4.3.4灵敏度测量测量方法 16
4.3.5镜像抑制比测量测量方法 16
4.4功能测试 16
4.5 测试结果分析 17
4.5.1性能测试结果分析 17
4.5.2功能测试结果分析 17
总结 18
致谢 19
参考文献 20
附录A系统结构总图 21
附录B 程序 22