流星雷達對70~140公里之間中氣層、低熱氣層觀測能力，歷經幾十年的發展，對於該範圍中性風場觀測已成熟獲得認可。流星燃燒後，產生電漿粒子形成流星尾，假設電漿團是凍結在背景大氣中，隨著背景風場移動。流星雷達觀測電漿形成的折射指數不規則體飄移速度，可獲得觀測範圍的背景水平中性風場。利用中性風場進行重力波、潮汐等的相關研究，一直不斷被進行著。台灣地區，電離層散塊E層主要發生高度範圍在80~120公里之間，在中低緯度發生的機制有風切理論與電漿不穩定(Plasma Instability)理論。根據前人的模擬重力波發生時，產生的電漿梯度不穩定效應，對電離層散塊E層的發生將有直接關聯性。計畫中將利用現有電離層雷達，結合未來總計畫建置的流星雷達，同時觀測電離層散塊E層與重力波，研究兩者之間的相關性。本計畫擬分三年執行，第一年，將配合總計畫流星雷達建置時程，針對流星雷達站址規畫、整建，並進行環境背景電磁輻射量測，系統規格制訂與採購，利用雷達干涉法分析電離層散塊E層訊號。第二年，進行流星雷達系統建置，散塊E層頻譜分析與相關性分析，並進行雷達系統校驗。第三年，完成流星雷達系統建置，開始實驗觀測，並配合電離層雷達聯合觀測，探討重力波與散塊E層相關性。 ;The mesosphere and lower thermosphere neutral wind between 70 and140 kilometers has been recognized for decades by using the meteor radars. The incomming meteors are burn to form meteor trail with high speed. Presume that the plasma of meteor trail is frozen in the background atmosphere and moves with the background wind field. The horizontal neutral wind field within this range can be derived from the drift velocity of plasma irregularities by the meteor radar observation.The related research of gravity waves and tides by neutral wind field have been continuously carried out. In Taiwan area, the ionosphere sporadic E layer mainly occurs at a height range of 80-120 km. The mechanisms of those phenomena that occur in the middle and low latitudes are wind-shear theory and plasma Instability theory. According to the previous simulation of gravity waves, the instability of the plasma gradient is correlated directly with the occurrence of sporadic E layer.In this sub-project, the existing ionospheric radar and the newly constructed meteor radar will be used to observe the sporadic E-layer and the gravity waves at the same time. This is a three-year project. In the first year, the sub-project will make procurement plan of meteor radar system, perform site survey and environmental radiation measurement. The installation, evaluation of meteor radar system and the interferometry analysis of sporadic E are carried out during the second year. In the last year, the meteor radar system construction is completed. It will be combined with ionosphere radar to study the relation between gravity wave and sporadic E layer.
