Detecting unexpected fall using array antenna

Nowadays, the population of the elderly people is increasing in Japan. The system to protect an elderly person who is living alone is needful. The bigger part of the accident in their house is falling. There are several kinds of products to detect a person's fall. However, there are some problems that it does not have enough detection range and privacy. Array antenna is an antenna, which detects radio wave propagation by observing the direction of arrival (DOA) of the signal. We developed previously the fall detection using array antenna. In the conventional fall detection method, it is needed to learn and observe the whole activity scenario, which includes how the person moves before and after the fall. As a result, when the unexpected fall scenario happens, it is not able to detect the fall correctly. In this paper, we propose a detection algorithm for unexpected fall using array antenna. We detect fall for every fixed time, and by the results of the detection, we decide whether the activity is falling or not. By using this method, it can detect the unexpected fall scenario, which is not learned. In addition, we use new features for support vector machine (SVM) to distinguish confusing activities and improve the fall detection accuracy.