MATCHED ABSORBING MEDIUM TECHNIQUES FOR FULL-WAVE TLM SIMULATION OF MICROWAVE AND MILLIMETER-WAVE COMPONENTS

This paper investigates the absorbing layer techniques for three-dimen sional transmission-line matrix (3D-TLM) simulations. Applications are rite full-wave analysis of structures such as microwave and millimete r-wave circuits open to free space. Two approaches are presented, name ly the matched layer (ML) and the perfectly matched layer (PML) techni que which is used for general cases. For the ML technique, which is ef ficient for matching guides operating in a quasi-TEM condition, a comp arison of the different TLM condensed node is carried out. Concerning the more general case of rite PML technique, the theoretical developme nt of a new general three-dimensional (3D) TLM condensed cell is prese nted. Results pertaining to the characterization of planar circuits ar e compared with other solutions or measurements. It is found that a pr oposed unified approach, which includes the TLM simulation for matched layer media, yields very good performance in terms of the absorbing b oundary condition (ABC).