一种用于LoRa可穿戴设备的小型化双频段天线

Miniaturized dual band antenna for LoRa wearable devices

提出了一种适用于LoRa可穿戴设备的小型化双频段天线.该天线由半径为18 mm的基板及上方高6 mm的圆环支架构成,利用顺时环绕单极子、耦合分支在一定小型化的结构上激励出两个低频谐振模式,满足LoRa天线性能要求.实测天线-10 dB阻抗带宽为476~502 MHz和854~879 MHz,能够覆盖LoRa设备在470~510 MHz和863~868 MHz的大部分工作频段,同时在490 MHz和865 MHz两个工作频率点测得效率分别为15.56%和27.91%.该天线结构简单,覆盖频率广,体积小,工作频带内具有良好的辐射性能,具有一定的工程应用价值.

A miniaturized dual-band antenna suitable for LoRa wearable devices is proposed. The antenna is composed of a substrate with a radius of 18 mm and above the 6 mm high ring bracket. A clockwise surround monopole and coupling branches are adopted to generate two low-frequency resonant modes on a certain miniaturized structure, which can meet the LoRa antenna performance requirements. The antenna achieves -10 dB impedance bandwidth of 476-502 MHz and 854-879 MHz, and can cover most of the working frequency bands of LoRa devices at 470-510 MHz and 863-868 MHz. The measured efficiency at the two operating frequency points of 490 MHz and 865 MHz is 15.56% and 27.91% respectively. The antenna has a simple structure, a wide coverage frequency, a small volume, and a good radiation performance in the working frequency bands, and has a certain engineering application value.