小型電離層探測儀（Compact Ionosphre Probe, CIP）是多合一電離層電漿量測科學酬載，為先進電離層探測儀（Advanced Ionospheric Probe, AIP）的改良版。CIP與AIP最大的差異在將AIP上的科學酬載電子系統（Science Payload Electronics Unit, SPEU）整合至探測器內部，不但降低功耗，也大大節省科學酬載的空間，使其更適合放置在立方衛星（CubeSat）上，如於由美國、印度、與台灣所合作的3U立方衛星－International Satellite Program in Research and Education Satellite-1（INSPIRESat-1），和未來太空中心所設計之3U立方衛星－Ionospheric Dynamics Explorer and Attitude Subsystem Satellite（IDEASSat），作為主要科學酬載。 作為科學酬載，CIP主要是以不同模式下所量測到的電流量，判斷該區域的電漿特性。為了使量測範圍更加符合任務操作的環境需求，本文分析了CIP所能收集到的離子及電子電流，並以此設定優化了電路的放大倍率。而所執行的科學任務之一，就是量測電離層F層中的電漿不規則體（Plasma Irregularities）。F層的電漿不規則體通常為電漿密度較低的電漿泡（Plasma Bubble），而密度低直接影響到科學酬載所能量測到的電流值下限，因此在CIP的設計上，更注重在提升儀器類比前端處理單元的系統靈敏度（system sensitivity）。即使在微小電流訊號的情況下，也能準確量測的電漿特性。CIP使用過取樣（oversampling）的方式，不僅簡化前置抗混疊低通濾波器的設計，也大大提升整體訊噪比。再以濾波器動態範圍（Filter System Dynamic Range）來判斷系統靈敏度。本文也為CIP的類比前端處理單元電路部分作詳盡的介紹，並對目前設計的原型體（Prototype）做功能測試，以驗證所設計的電路之功能性。;Compact Ionoshpere Probe (CIP) is an all-in-one plasma sensor which could perform multiple sensor functions with single instrument, and an improved version of Advanced Ionospheric Probe (AIP). The most significant difference is that CIP integrates the Science Payload Electronics Unit (SPEU) into the sensor so that it could reduce power consumption and make sensor size fit in 1U. It is more suitable for cubesat and CIP would be the major science payload of INSPIRESat-1, which is a 6U cubesat. As the science payload, CIP measures the current in different modes to diagnosis the characteristic of plasma. In this research, we will analyze the current flux of ion and electron and determine the gain of our current meter to ensure the range of measurement to match the requirement. One of the science missions is to measure Plasma Irregularities in F-layer. That the density of plasma irregularities is lower than that of environment generally would affect the current minimum which we can measure. When we design this instrument, we focus on improving the system sensitivity of CIP, including increasing the dynamic range of filter system, which represents the current minimum value distinguished by CIP, with oversampling and 2nd order filter. We would introduce the design of Analog Preprocessing Unit (APU), and examine some functional tests for CIP prototype to verify the design and function reasonably.
