一款应用于脑活动探测的宽带天线系统设计

为利用微波传输法对大脑活动进行探测，提出了一款应用于大脑活动探测的宽带天线.该天线单元为微带单极子天线，由开槽矩形宽缝、三角形贴片极子和反射板构成，采用微带线馈电，直接与人体头组织介质匹配，经过仿真优化，该天线-10 dB回波损耗带宽覆盖了工作频率范围2.3~8 GHz.并仿真分析了大脑内的电磁能量传输特性及电场分布，结果显示介质匹配天线相比普通天线在头颅内具有更好的穿透能力，在大脑皮层和深部脑区仍存在较强的电场强度.最后对此宽带天线进行了加工测试，实测数据与仿真结果基本吻合.该天线单元尺寸小、结构简单、易加工，能够很好地满足微波传输法探测大脑活动技术中头部共形天线阵列的设计要求.

Design of a broadband antenna system for brain activities detection

This paper presents a broadband antenna for brain activity detection.The antenna is a microstrip monopole, which consists of a slotted rectangular wide seam, a triangular patch and a reflector.The antenna is matched to the human head tissue directly.The-10 dB return loss bandwidth covers the operating frequency range of 2.3-8 GHz.And the electromagnetic energy transfer characteristics and electric field distribution in the brain is simulated.The results show that the on-body matched antenna has better penetrating ability inside human's head than the conventional antenna, and appreciable intensity of electric field can still be found in cerebral cortex.The simulated and measured results are consistent with each other very well.The antenna features small size, simple and compact structure.Meanwhile, it meets the design requirements of antenna array well in brain activity detection system.