電壓控制LC振蕩器

電氣自動化論文編號:ZD838    論文字數:12189,頁數:27

目 錄
摘要……………………………………………………………………………………………………I
Abstract……………………………………………………………………………………………II
第1章  前言…………………………………………………………………………………………1
 1.1  課題的背景和意義…………………………………………………………………………1
 1.2  國內外壓控振蕩器的現狀和發展…………………………………………………………1
第2章  總體方案設計……………………………………………………………………………4
 2.1  LC壓控振蕩器電路的選擇…………………………………………………………………4
 2.2  高頻功率放大電路的選擇…………………………………………………………………5
 2.3  頻率控制方式的選擇………………………………………………………………………6
第3章  系統設計…………………………………………………………………………………9
 3.1  總體設計……………………………………………………………………………………9
 3.2  各模塊設計及參數計算……………………………………………………………………10
 3.3  軟件部分的設計……………………………………………………………………………18
第4章  系統調試…………………………………………………………………………………20
 4.1  單片機最小系統的調試……………………………………………………………………20
 4.2  壓控振蕩器模塊的調試……………………………………………………………………20
 4.3  功率放大模塊調試  ………………………………………………………………………21
第5章  指標測試…………………………………………………………………………………22
 5.1  測試儀器……………………………………………………………………………………22
 5.2  指標測試……………………………………………………………………………………22
 5.3  數據分析說明………………………………………………………………………………22
第6章  結論………………………………………………………………………………………23
致謝……………………………………………………………………………………………………25
參考文獻………………………………………………………………………………………………26

摘要
 在LC振蕩器的LC回路中，使用電壓控制電容器（變容器），就可以在一定頻率范圍內構成電調諧振蕩器。即電壓控制LC振蕩器。壓控振蕩器可廣泛使用于頻率調制器，鎖相環路，以及無線電發射機和接收機中。
 系統主要采用MC145152、MC1648和預置雙模分頻器B571集成芯片為核心，由單片機89C52以及CPLD控制模塊、鍵盤輸入模塊、液晶顯示模塊、可編程壓控增益放大器模塊、輸出功率放大模塊和振蕩器輸出電平指示模塊構成。本系統的VCO部分采用了大變化范圍的變容二極管做振蕩電容，頻率調節范圍寬，在輸入電壓從0.5V變化到8V時，輸出頻率可以從14MHz變化到39MHz，且能保持良好的線性度，振蕩環路加入了防振措施，高次諧波能得到很好的抑制，輸出的正弦波波形良好，純度高，失真低，幅度高且穩定。由于采用了數字鎖相技術，使VCO的頻率穩定度和精度極高，步進值可以在1KHz到1MHz內任意設置（最小為1KHz），為了實際使用方便和考慮到題目要求，本設計的步進值置為100KHz。。
 
 
 關鍵詞 壓控振蕩器；數字鎖相環；單片機嵌入式系統；高頻功率放器

Abstract
This voltage control LC oscillator system controls the oscillator including the pressure (VCO), the digital phase-lock link (PLL), the monolithic integrated circuit (MCU) inserts the type system, high frequency power amplifier (RFAMP).
The system mainly uses MC145152, MC1648 and the initialization double model frequency divider B571 integration chip is a core, by monolithic integrated circuit 89C52 as well as the CPLD control module, the keyboard entry module, the liquid crystal display module, the programmable pressure controls the gain amplifier module, the output enlargement module and the oscillator power output instruction module constitution. This system VCO part used the sweeping change scope varactor to do vibrates the electric capacity, the frequency control scope is wide, when the input voltage changed from 0.5V to 8V, the output frequency may from 14MHz change to 39MHz, also could maintain the good linearity, vibrated the ring circuit to join the antivibration measure, the higher harmonic could be under the very good suppression, the output sine wave profile is good, the purity was high, distorts lowly, the scope was high also is stable. Because has used the numeral phase lock technique, causes VCO the frequency stability and the precision is extremely high, step-by-steps the value to be possible to establish (slightly in 1KHz to 1MHz in is willfully 1KHz), in order to the actual easy to operate and considered the topic request, this design step-by-steps the value to set is 100KHz.。

Keywords：The pressure controls the oscillator; Digital phase-locked loop; Monolithic integrated circuit embedded system; The high frequency power puts