(using simpler formula for demonstration) [ R_\textin(0) \approx 90\frac4.4^24.4-1\left(\frac28.437.3\right)^2 \approx 90\times\frac19.363.4\times0.58 \approx 297\ \Omega ]
[ L = \frac3e82\times2.45e9\sqrt4.18 - 2\times0.00074 \approx 28.4 - 0.00148 \approx 28.4 \text mm ]
[ y_0 = \frac28.4\pi \cos^-1\sqrt\frac50297 \approx 9.04 \times \cos^-1(0.41) \approx 9.04 \times 1.148 \approx 10.4 \text mm ] inset fed patch antenna calculator
[ W = \frac3e82(2.45e9)\sqrt\frac4.4+12 \approx 37.3 \text mm ]
Use these equations to build your own calculator in Excel, Python, or MATLAB. inset fed patch antenna calculator
If ( R_\textin(0) ) is not known from the exact formula, use the approximation: [ R_\textin(0) \approx 90\frac\varepsilon_r^2\varepsilon_r - 1\left(\fracLW\right)^2 \quad (\textfor thin substrates) ] Given: ( f_r = 2.45 \text GHz ) ( \varepsilon_r = 4.4 ) (FR4) ( h = 1.6 \text mm ) ( Z_0 = 50\ \Omega )
To match the feed line impedance ( Z_0 ) (e.g., 50 Ω): [ Z_0 = R_\textin(0) \cos^2\left(\frac\piLy_0\right) ] [ y_0 = \fracL\pi \cos^-1\sqrt\fracZ_0R_\textin(0) ] inset fed patch antenna calculator
[ \varepsilon_\textreff = \frac4.4+12 + \frac4.4-12\left(1+12\frac1.637.3\right)^-0.5 \approx 4.18 ]