We propose an antenna designed to generate monochromatic electromagnetic knots and other ‘unusual electromagnetic disturbances’ in the microwave domain. Our antenna is a spherical array of radiating dipolar elements configured to approximate the desired electromagnetic field near its centre. We show numerically that a specific embodiment of the antenna with a radius of 61.2 cm and only 20 element pairs driven at a frequency of 2.45 GHz can yield linked and torus-knotted electric and magnetic field lines approximating those of an ‘electromagnetic tangle’: a monochromatic electromagnetic knot closely related to the well-known Raada–Hopf type electromagnetic knots but simpler in its construction. The antenna could be used to locally excite plasmas.

我们提出了一种设计用于在微波域中产生单色电磁结和其他“异常电磁干扰”的天线。我们的天线是辐射偶极元件的球形阵列，配置为在其中心附近近似所需的电磁场。我们以数字方式表明，半径为 61.2 cm 且仅 20 个元件对以 2.45 GHz 频率驱动的天线的特定实施例可以产生链接的和环结的电场线和磁场线，近似于“电磁缠结”：单色电磁结与著名的 Raada-Hopf 型电磁结密切相关，但其结构更简单。该天线可用于局部激发等离子体。