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There are leading and innovative techniques that help realize a solver which brings accurate simulation results quickly. Among them, EIT (Embedded Integral Technique), a self-developed and leading technique based on FDTD (Finite-Different Time-Domain), is the main algorithm of ZWSim-EM. Others are:


Upgraded Conformal Technology:

It overcomes the defects which occur when using FDTD algorithm in complex geometric processing, to ensure second-order accuracy and efficiency.

Irregular Grid Processing Technology:

It overcomes the defects which occur when using Conformal-FDTD algorithm in time step, to ensure calculation efficiency without reducing time step.

Leading Model Discreteness:

The model discreteness is robust and can handle any pathological triangle models, including the ones that degenerate into points and lines.

Optimized Kernel Algorithm:

The kernel algorithm has been specially optimized to make its calculation faster than the traditional algorithms.



For pre-processing, ZWSim-EM supports unit setting, model building, materials assigning, background and boundary setting, excitation signal setting, excitation source setting, mesh setting, solver setting and checking. This preparation process is clear, convenient and complete, to ensure that your simulation runs smoothly and your results are displayed ideally.

Powerful Modeling Capabilities

Based on ZW3D’s powerful modeling capabilities, ZWSim-EM can meet different modeling requirements in the electromagnetic field.

24 model formats can be imported, such as .sat, .stp and .igs. You can directly do modeling in ZWSim-EM by parametric modeling driven by history tree, which greatly improves modeling efficiency, facilitates subsequent parameter sweeping and optimization, and is convenient especially for complex structures. Also, you can save a model to the component library with all of its current settings so that it can be opened and used directly afterwards.


Abundant Material Library

ZWSim-EM provides a rich material library containing more than 160 kinds of materials, offering you diversified electromagnetic materials to assign.

For shape models, hundreds of kinds of materials can be chosen. For Infinitely Thin Faces, PEC materials are provided. You can also customize materials according to your specific needs, and add the newly-created materials to the material library, which is convenient for you to access and reuse.


Multiple Array Patterns

ZWSim-EM provides powerful array capabilities for antennas, realizing efficient pre-processing of array antennas simulation.

It supports arraying antenna units to form the array antennas and meet the simulation requirements. A variety of array patterns are available, such as linear array, circular array, polygonal array, point-to-point array, and array along curves or surface. What’s more, models, materials and ports can be arrayed simultaneously to help simulate array antennas efficiently.


Multiple Background and Boundary Options

There are various kinds of background and boundary, meeting your needs of simulating different electromagnetic objects like antennas and waveguides.

The default background material is Vacuum, or you can also choose others from the material library or define by yourselves. Various boundaries such as Open boundary (default), PEC, PMC and Periodic are supported. For antenna simulation, the background can be Vacuum, and the boundary is Open. As for the simulation of waveguides like power dividers, filters, etc., the background can be conductors like PEC, while the boundary must be PEC.


Multiple Excitation Sources/Ports

ZWSim-EM offers multiple excitation sources and different ways to excite them. You can choose which ports to be excited, and to excite sequentially or simultaneously.

There are four types of ports in ZWSim-EM: Dipoles, Lumped Ports, Wave Ports and Plane Wave Ports. Lumped Ports and Wave Ports are mostly used in the antenna simulation, and Plane Wave Ports are usually used in the RCS simulation. For the models with multiple ports, ZWSim-EM provides two ways to excite them: Sequential Excitation (default) and Simultaneous Excitation. The excitation amplitude, phase (default: 0), delay, etc. of each port can be set and edited.


Multiple Mesh-generation Strategies

ZWSim-EM provides different mesh-generation strategies to satisfy different accuracy requirements. Receiving correct simulation results by less meshes and shorter time can be realized.

There are three mesh-generation settings: General Mesh, Local Mesh and Critical Position Mesh. For general model simulation, the General Mesh with default settings will do. If the model is more complex, the Local Mesh which refines mesh for the complicated parts, and Critical Position Mesh which divides critical points by mesh lines will help.


Intelligent Checking

You can check the project by analyzing and adjusting accordingly to ensure the validity of pre-processing settings, so that the simulation can run smoothly.

There are multiple checking options, including Overlapped Objects Checking, Background and Boundary Checking, Excitation Signal Checking, Excitation Source Checking, Probe Checking, Mesh Checking and Solver Checking. The passed items will be marked as “√”, while the failed ones will be marked as “×” with an error warning in the message board.



For post-processing, ZWSim-EM supports checking 1D, 2D and 3D results, importing and exporting results, mathematically processing results, tracking the features of results, labeling, logs, etc. The simulation results can be shown intuitively and multi-dimensionally, making it convenient for you to post-process.

One-Dimensional Results


From One-Dimensional results, you can clearly get to know the situations of Port Signal, E-probe, H-probe, Load Impedance, Power, Efficiency, S-parameters, Y-Parameters, Z-Parameters and VSWR.

One-Dimensional results can be demonstrated by the Z and Y Smith Charts, which can only be generated based on S-Parameters. Also, multiple indicators of results can be displayed, including phase, real part, imaginary part, linear and decibel.

One-Dimensional Results


ZWSim-EM supports frequency sweeping of Far-Field, which can help to know how Far-Field results change with frequency in a specific direction. It can also obtain Far-Field results for a certain frequency point. In addition, the Far-Field results can be directly arrayed, allowing you to quickly get the results for array antennas.

It offers both linear and decibel displays for Far-Field results, which can be demonstrated by Cartesian Coordinates, Polar Coordinates, 2D Display and 3D Display. Multiple indicators can also be displayed, including directivity, gain, realized gain, rE, polarization ratio, and axial ratio.

E/H Field Results


From E/H Field results, you can check how the field changes with the phase, which is dynamically displayed. To get a better display effect of the field values, ZWSim-EM provides options including Linear, Log Scale, dBm and dBμ.

The E/H field and its surface current can be displayed in 3 ways, including Arrows, Bubbles and Contours. For Arrows and Bubbles, you can adjust the display effects of the arrows and bubbles by setting the density, size and phase. For Contours, you can set the phase and cutting plane to check the field distribution on the section, which can be cut by ±X, ±Y, ±Z.

Parameter Sweep


Parameter Sweep helps you check how the results are influenced under a specific range of parameters, and optimize accordingly to get the expected results.

You can scan and simulate the settled variable parameters, and analyze how the parameters in a specific range affect the results, to provide references to optimize the models and improve your design efficiency. You can establish multiple sweeping tasks and add multiple sweeping parameters to each task.

System Requirements
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