頻率調變連續波液面雷達電路設計

Abstract

本論文是以頻率調變連續波雷達的基本原理，設計並研製液面雷達電路。液面雷達功能使用於量測貯存槽之液面距離，從而得到所貯存物質之存量。設計之雷達電路，其射頻訊號係利用壓控振盪器產生4.5GHz至4.75GHz頻率調變訊號，經過倍頻器升頻至9GHz至9.5GHz後發射，雷達回波信號與發射信號混波後，其差頻信號頻率即都卜勒頻率，據以由計頻器得知反射之液面距離。 論文之第二章敘述頻率調變連續波雷達的基本原理，與液面雷達的電路規劃。第三章則敘述電路所使用元件之特性，電路設計與佈局，以及功率分配器、衰減器之電路製作與元件量測結果。第四章敘述電路組裝過程中各階段之測試與量測結果，以及組裝後之實測結果。第五章為論文結論。

The content of this thesis is based on the principle of FMCW radar to design and implement the level radar circuits. Level radar is used to measure the liquid level in chemical tanks, and thereby counts the amount of the content. The radar RF signal is generated from a VCO with frequency from 4.5GHz to 4.75GHz, then gives to 9GHz to 9.5GHz through a multiplier, for radiation from the antenna. The radar received signal is then mixed with the transmitted signal to give a Doppler frequency signal to be processed by a counter to yield with the level distance. In Chapter 2, description on the FMCW radar principle and the schematics of level radar are presented. Chapter 3 describes the characteristics of each component, circuit design, layout, circuit implementation, and measurement results of power divider and attenuator. Chapter 4 then describes the test and measurement results in each step of assembling, and the measured results of a distant object. Chapter 5 is the conclusion.