Large Patch Array behind Car Bumper

The application note demonstrates excellent performance of WIPL-D suite for simulation of very large arrays of microstrip patch antennas. The microstrip with finite ground plane array has over 150 elements. Simulation frequency of interest is 70-80 GHz (specifically 77 GHz).

The model of the array is placed behind large metallic grill, which is then immersed into dielectric (plastic). This mimics the realistic situation where antenna array is covered by a car bumper.

A rather simplified formula estimates number of elements in patch array as number of elements multiplied by 500. This estimation applies when patch is placed above infinite PEC plane, and increases to 1000 when the ground is finite. Here, the number of unknowns is approximately 124,000, without any number of unknowns reduction applied. With the grill added, and again without reductions, the number raises to 190,000.

Finally, reduction of referent frequency, which should be set to only 32 GHz, is used for the plastic to which the grill is immersed. This yields in 290,000 unknowns.

All simulations are carried out on inexpensive server comprising of multiple core CPU and 4 low range Nvidia GTX GPU cards. The simulation times are couple of hours at most.

Domain Decomposition Solver (DDS) is intended for high frequency problems, since MoM poorly scales with frequency. This is an iterative solution. In our case, a fully convergent result is obtained after iteration #4 and beyond (the total of 15 iterations were examined). Previous iterations also show excellent accuracy, with each iteration being of approximately the same duration (under an hour).

Section: Arrays & Radomes

For full version of the document, please check the following pdf.