This article presents a comprehensive study of the use of small-sized frequency selective surfaces (FSS) to selectively shield pocket-sized devices against EM disturbances. A typical use case is to protect a 2.4-GHz transceiver (e.g. WiFi/Bluetooth) against ISM/GSM disturbances (around 868/915 MHz), using an 8.2 × 4.1 cm FSS structure. A detailed comparison is drawn between results in real and emulated far-fields for different FSS-to-antenna distances (5 and 25 mm), which is further confirmed by emission measurements employing an open transverse electromagnetic cell. Results demonstrate, in line with full-wave simulations including calculated Poynting integrals, that such a FSS can effectively reduce power by about 5 dB in the stopband, while providing no attenuation in the passband and is small enough for an easy integration. Moreover, it is shown that the farther the FSS from the antenna, the closer the results to a no-FSS scenario. This provides an insight to reconsider FSSs for the shielding of mobile and/or smart devices.

中文翻译：

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用于袖珍型收发器电磁屏蔽的选频面

本文全面研究了使用小尺寸频率选择表面 (FSS) 来选择性地屏蔽袖珍设备免受 EM 干扰。一个典型的用例是使用 8.2 × 4.1 cm FSS 结构保护 2.4-GHz 收发器（例如 WiFi/蓝牙）免受 ISM/GSM 干扰（大约 868/915 MHz）。对不同 FSS 到天线距离（5 和 25 毫米）的真实远场和仿真远场结果进行了详细比较，这通过采用开放横向电磁单元的发射测量得到了进一步证实。结果表明，与包括计算的 Poynting 积分在内的全波模拟一致，这种 FSS 可以有效地将阻带中的功率降低约 5 dB，同时在通带中不提供衰减，并且足够小以易于集成。而且，结果表明，FSS 离天线越远，结果就越接近无 FSS 场景。这提供了重新考虑 FSS 以屏蔽移动和/或智能设备的见解。