AWR Application Notes

AWR Software for the Design of MIMO and Phased Array Antenna Systems 5 www.cadence.com/go/awr Individual Antenna Design In the previous example, the 5 x 15 array presented the radiation patterns for an ideal isotropic antenna (gain = 0dBi) and a simple patch antenna. In addition to the array configuration itself, the design team would likely want to specify the radiation pattern and size constraints for the individual antenna elements. This operation can be performed using the synthesis capabilities in AntSyn software, which uses an EM solver driven by proprietary evolutionary algorithms to explore multiple design options based on antenna specifications defined by the engineer. These specifications include typical antenna metrics, physical size constraints, and optional candidate antenna types. In Figure 7, AntSyn software creates antenna geometries from its database of design types and then applies EM simulation and its unique evolutionary optimization to modify those designs and achieve the required electrical performance and size constraints. A run-time update of the design types under investigation is listed, along with a star rating system to indicate which designs are close to achieving the desired performance. Promising designs can then be exported to AWR Design Environment. Figure 7: The AntSyn project tree and candidate antenna designs with their star ratings, results can be viewed and exported Due to its relatively small size and easy fabrication, a square-ring patch antenna was chosen from the potential antennas created by AntSyn software. The antenna was exported using the AWR AXIEM options and then imported into a new AWR AXIEM EM structure in the initial phased array project. The re-simulated antenna is shown in Figure 8. Figure 8: Square-ring antenna analyzed by AWR AXIEM software. Resulting antenna pattern can feed an AWR VSS phased array model This simulation provided the antenna pattern to replace the original patch antenna used in the 5 x 15 phased array with the new antenna pattern shown in Figure 9. The new phased array results for both the original antenna (red trace) and the square-ring patch (green trace) are shown in Figure 9 as well. Figure 9: Patterns of single-patch and square-ring antennas generated by AntSyn software and comparison of radiation patterns from phased arrays based on simple patch antenna (red) and square-ring patch antenna (green)

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