在使用電離層觀測儀觀測天波時，在觀測資料上總會有些一日性的週期變化，普遍會以電離層之電子濃度變化來解釋，在地波資料上也有同樣情形，但卻無法以電子濃度變化來解釋，這篇論文主要由地波的角度來說明地波環境背景強度波動的變化情形，由屏東動態式電離層觀測儀加上環形天線所觀測到的地波資料，選出周圍特定調幅站台的頻率，並以大氣環境模式(Weather Research and Forecasting, WRF)得到大氣環境資料，藉由地波資料的強度變化與大氣環境變化的相對關係，對應到於地波理論中的大氣波，判斷其合理性，並說明與大氣環境變化的關係。

When we observe the sky-wave data by dynasonde, we find that observation data has some period during one day. We always says that the reason is the difference of electronic density. But when we find the some problem in the ground-wave, the reason as same as sky-wave. In this thesis, we will explain the variation caused by the background surrounding oscillation with ground-wave. The purpose of thesis is to use the ground-wave data measured by the circle antenna compare with the atmospheric data observed by WRF model.

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