Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome, Italy.
Larimart S.p.A., Rome, Italy.
Front Public Health. 2022 Feb 3;9:794564. doi: 10.3389/fpubh.2021.794564. eCollection 2021.
The use of electromagnetic (EM) technologies for military applications is gaining increasing interest to satisfy different operational needs, such as improving battlefield communications or jamming counterpart's signals. This is achieved by the use of high-power EM waves in several frequency bands (e.g., HF, VHF, and UHF). When considering military vehicles, several antennas are present in close proximity to the crew personnel, which are thus potentially exposed to high EM fields.
A typical exposure scenario was reproduced numerically to evaluate the EM exposure of the human body in the presence of an HF vehicular antenna (2-30 MHz). The antenna was modeled as a monopole connected to a 3D polygonal structure representing the vehicle. Both the EM field levels in the absence and in the presence of the human body and also the specific absorption rate (SAR) values were calculated. The presence of the operator, partially standing outside the vehicle, was simulated with the virtual human body model Duke (Virtual Population, V.3). Several exposure scenarios were considered. The presence of a protective helmet was modeled as well.
In the area usually occupied by the personnel, E-field intensity radiated by the antenna can reach values above the limits settled by international safety guidelines. Nevertheless, local SAR values induced inside the human body reached a maximum value of 14 mW/kg, leading to whole-body averaged and 10-g averaged SAR values well below the corresponding limits.
A complex and realistic near-field exposure scenario of the crew of a military vehicle was simulated. The obtained E-field values radiated in the free space by a HF vehicular antenna may reach values above the safety guidelines reference levels. Such values are not necessarily meaningful for the exposed subject. Indeed, SAR and E-field values induced inside the body remain well below safety limits.
为了满足不同的作战需求，例如改善战场通信或干扰敌方信号，电磁（EM）技术在军事应用中的使用越来越受到关注。这是通过在多个频带（例如高频、甚高频和特高频）中使用高功率 EM 波来实现的。在考虑军用车辆时，几个天线靠近机组人员，因此他们可能会暴露在高强度的 EM 场中。
通过数值再现典型的暴露场景，评估在高频车载天线（2-30MHz）存在下人体的 EM 暴露情况。将天线建模为连接到代表车辆的 3D 多边形结构的单极天线。在不存在和存在人体的情况下计算 EM 场水平和比吸收率（SAR）值。使用虚拟人体模型 Duke（虚拟人群，V.3）模拟操作员部分站在车外的情况。考虑了几种暴露场景。还模拟了防护头盔的存在。
在人员通常占据的区域，天线辐射的 E 场强度可以达到国际安全指南规定的限值以上。然而，在人体内部感应的局部 SAR 值达到了 14mW/kg 的最大值，导致全身平均和 10g 平均 SAR 值远低于相应的限值。
模拟了军用车辆机组人员的复杂而现实的近场暴露场景。由高频车载天线在自由空间中辐射的 E 场值可能达到安全指南参考水平以上的值。这些值对于暴露的对象不一定有意义。实际上，体内感应的 SAR 和 E 场值仍远低于安全限值。
