近年來登山運動逐漸盛行，也因此造成山難事件層出不窮，然而當山難發生時，目前卻沒有一個能有效輔助山難救援的系統，只能依靠救難隊地毯式的搜索，不僅相當費時也相當費力。如果有一個系統在救難行動時，能在廣大的山區縮小搜救的可能範圍或是給予搜救路線的指引方向，將大大提升搜救的效率，也能夠增加遇難者的生存機率。如果要實現此系統，首先需要克服在山區大範圍且遠距離的條件下設備間能正常傳輸資料，且要不受限於在山區中時常訊號不佳的電信業者。本論文提出一個藉由LoRa通信技術來推測出發生山難之登山客可能位置的方法。其主要流程為登山客身上之設備會藉由LoRa不斷發送訊號，一旦救難隊的設備收到此訊號便藉由此次訊號之RSSI推測兩者之間的距離差距，再藉由不同地點所得到之距離差距以及救難隊本身位置資訊，利用定位演算法推測出登山客所在的可能位置。透過上述的方法，系統便能推算出一個登山客可能的所在位置，救難隊也就能朝著此位置的方向移動，搜索此推測位置附近的區域，以達成幫助救難隊減少需要搜索的區域範圍並且提高山難的獲救率。

In recent years, mountain climbing has become more and more popular exercise, and as a result, there are more and more mountain accidents happened. However, when the mountain accidents happened, it is very difficult for rescue. It is due to that there is no way which can effectively provide the location of the mountain disaster. It can only rely on the blanket searching of the rescue team, which is not only time-consuming but also laborious. If there is a system can narrow down the searching and rescue region or give some guidance for the searching and rescue route, which will get a greatly improvement of the rescue action and also increasing the survivability of the victims. In this study, a method for estimating a possible area or location of the mountain climbers by LoRa communication technology was proposed. The idea is that a mountain climber wears a LoRa communication device with him, the LoRa communication device will periodically send signal out. The equipment of the rescue team receives the LoRa signal, from the RSSI of the received signal, it can be used to estimate the distance and location or area among the victim and rescuers, by positioning algorithm. To assess its availability of the proposed method, an experiment system has been designed and tested in the mountain area where the commercial telecommunication signal is not reached. The results show it meets the requirements.

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