Design and Implementation of a Miniature X-Band Edge-Coupled Microstrip BPF Using AWR Software
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EM Simulation
The AWR AXIEM® planar method-of-moments (MoM) simulator within AWR Design Environment software was used to validate
the BPF design, as shown in Figures 7.
Figure 7: AWR AXIEM EM layout with ground plane and with mesh density annotation
The AWR AXIEM software solves for the currents on conductors embedded in a stackup of planar dielectric layers. MoM is a
full-wave numerical technique that solves the integral form of Maxwell's equations using the approximation that the dielectric
layers are of infinite extent in the x-y plane.
Once the EM simulations were carried out, the calculated current density can be annotated over the entire EM structure, as
shown in Figure 9.
Figure 9: AWR AXIEM current density EM annotation
This annotation enables the designer to specify the frequency, phase, vector components, and color scaling associated with
the magnitude of the current. It also supports the use of cut planes to enable designers to investigate current densities
occurring within a more complex multi-layer structure through dissection of the PCB.
The EM simulation results in Figure 9 are shown in comparison to the circuit simulation results. The EM results were very
similar to the circuit results and matched exactly the performance parameters with insertion loss in the frequency range of
8.4GHz to 9.3GHz with approximately 5dB and return loss well below 12dB.
Figure 9: Comparison of circuit and EM simulation results (graph and table).
Parameter Circuit Schematic
Electromagnetic
AXIEM
Insertion
Loss
1) 8.4GHZ = -4.90dB
2) 9.3 GHz = -4.92dB
1) 8.4GHZ = 4.96dB
2) 9.3 GHz = 4.98dB
Return Loss
1) 8.4GHZ = -13.27dB
2) 9.3 GHz = -24.34dB
1) 8.4GHZ = 19.45dB
2) 9.3GHZ = 17.44dB
