近年來，隨著無線傳輸技術的提升，以無線電力傳輸(Wireless Power Transmission，WPT)方式可將能量依電磁波之射頻形式進行傳送。而藉由無實體電線之微波形式傳送至接收端，具有高便利性、高安全性等優點，因此無線電力傳輸技術至今仍有其廣泛之應用。
本實驗設計於WiFi頻率落在2.4~2.4835 GHz之間。藉由貼片天線(Patch Antenna)之指向性將能量聚集，再利用增加單元數天線，設計為陣列式天線以提升增益及輻射效率。其增益值由0.49 dBi提高至8.7 dBi，輻射效率由20.4 % 大幅提升至87.2 %，使得天線之間傳輸能量損耗降低。並量測陣列式天線與天線間之傳輸與接收能量，得到當天線之間相距為1 cm下，藉由頻譜分析儀量測接收的能量為182 µW，因陣列式天線具有高增益及高效率的特性，其接收功率為單一貼片天線之4.7倍。

Wireless Power Transmission (WPT) is a hot issue for energy transmits method nowadays. In WPT system, distance, gain and efficiency transmission are the key factors between transmitter and receiver. In this paper we focus on the Microwave Radiation method and would use a patch antenna array for our experiment. Some of the advantages of patch antenna array are high gain, high directivity. By combining several antennas in an array configuration, the performance would increase tremendously comparing to a single element. The result of this experiment shows that the antenna's characteristic of gain increased from 0.49 to 8.7 dBi, and the radiation efficiency increased from 20.4 % to 87.2 %. When the distance of each array patch antenna is 1 cm, the energy receive is measured as 182 µW. However, when antenna’s transmission distance is far from the other, the power which the antenna received will decrease. Compared to a single element array, the array antenna has higher gain of energy and further transmission distance. Thus it can receive more power and the efficiency can be highly promoted.

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