Method for simulating an antenna

Method for simulating electromagnetic interactions between an antenna and an electrically large interaction structure placed in a radiation direction in front of the antenna,

• wherein the antenna comprises a reflecting front face and at least one radiating element,
• the method comprising:
• providing, in a memory unit of a computer, an antenna model representing the antenna, the antenna model comprising
• an antenna surface representing the reflecting front face of the antenna and at least one field source representing at least one electromagnetic radiator of the antenna,
• wherein the at least one electromagnetic radiator is defined as a part of the antenna that at least partly comprises the radiating element and that has dimensions that place the interaction structure in the far field region of the radiator;
• wherein the field source is placed at the antenna surface,
• wherein the field source is configured as a far field source that is defined by a predetermined radiation pattern,
• wherein a radiation field of the radiation pattern that is directed towards the antenna surface is at least approximately equal to zero so that direct electromagnetic interaction between the field source and the antenna surface is avoided;
• computing, with a processing unit of the computer, electromagnetic radiation launched by the field source based on the predetermined radiation pattern;
• propagating, with the processing unit of the computer, the radiation in the radiation direction using an asymptotic numerical method;
• and
• determining, with the processing unit of the computer, interactions of the radiation with the interaction structure and with the antenna surface.