熱輻射感測系統與功率放大器設計

Abstract

熱成像技術是被動接受環境熱輻射，判斷溫度後去做分析。比起紅外線偵測，毫米波在空間中傳播時受到水氣和灰塵的影響較小。此技術在安檢、遠距離觀測和軍事上都有所運用，此篇論文探討的為軍事用途上，熱追蹤雷達的晶片設計。接收器中心頻率設計在35GHz為了減少空氣中傳播的損耗，系統操作時雷達在空中旋轉，在過程中找出最熱的物體加以鎖定，接收器的溫度接收範圍設計在 0°C ~ 100°C 的溫度區間，量測的結果在適當的積分時間設計下，精準度可達到1°C。 另外一個10GHz功率放大器設計，目標是在CMOS製程下最大的輸出功率。在較低的崩潰電壓限制下，CMOS製程的功率放大器的最大輸出功率比起其他製程要小。使用Cascode的電路架構以達到更大的輸出功率，變壓器基底的匹配電路設計使電路有更小的佈局。在加入電磁模擬後，功率放大器可以達到26dBm的最大輸出功率，最大功率附加效率和1dB壓縮點分別為24% 和0dBm。

Passive millimeter wave imaging is method of forming images through the passive detection of naturally occurring millimeter scene radiation. Compared to infrared or visible system, the millimeter wave system has much better ability to penetrate poor weather, dust and smoke. In this radiometer system, we use this method to build up a heat-seeking radar and provide a fully-integrated solution. By rotating in the air, the system can distinguish surrounding temperature and target the hottest subject. To minimize the attenuation in the air, the center frequency of the receiver is design at 35GHz. The detection range of the receiver is from 0°C to 100°C. With a proper calibration and a sufficient integration time, the system accuracy can achieve 1°C. Another 10GHz power amplifier (PA) is designed to aim for the largest output power. Using cascade topology to achieve higher output voltage. The transformer based matching network effectively reduce the chip size. The output power achieve 26 dBm in simulation result. And the peak PAE and P1dB are 26% and 0dBm, respectively.