how to find input impedance of rectangular microstrip patch antenna?

i want to design 2*2 microstrip patch antenna array with micrrostrip line feeding network
but on an important factor is to find input impedance of each patch, so how can i find input impedance?

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follow the basics given in the book by Balanis, and find the feed point as per the formula given there.
once you have got the point, you may use HFSS to plot the input impedance, and then optimize the plot to make the re(Zin) as close as possible to 50 ohms for perfect matching.
you can easily obtain Zin curve by plotting terminal Z parameter and then selecting Z11 V/S FREQ WHICH IS NOTHING BUT THE DRIVER SIDE INPUT IMPEDANCE.

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follow the basics given in the book by Balanis, and find the feed point as per the formula given there.
once you have got the point, you may use HFSS to plot the input impedance, and then optimize the plot to make the re(Zin) as close as possible to 50 ohms for perfect matching.
you can easily obtain Zin curve by plotting terminal Z parameter and then selecting Z11 V/S FREQ WHICH IS NOTHING BUT THE DRIVER SIDE INPUT IMPEDANCE.

thaaaanks:)