[ y_0 = \frac{L}{\pi} \cos^{-1} \sqrt{ \frac{50}{Z_{edge}} } ]
She laughed — a tired, relieved laugh. The calculator hadn’t lied. The cosine-squared impedance taper worked.
To find ( y_0 ) for ( Z_{in} = 50 \ \Omega ):
W = 37.26 mm L = 28.23 mm Inset depth y0 = 8.12 mm Inset gap = 2.0 mm (default) Priya held her breath. The numbers were clean — not suspiciously round, not chaotic.
Her mission: design a compact 2.45 GHz patch antenna for a wildlife tracking collar. It had to be tiny, efficient, and cheap. No room for bulky coaxial probes or intricate matching networks. Only one option remained: the .
And Priya? She stopped fearing the inset feed — because now, she had the numbers to trust. For an inset-fed rectangular patch:
Priya knew the formula by heart, but manual errors had already melted two prototypes. The first: return loss of -4 dB (basically a heater). The second: resonant at 2.7 GHz (hello, satellite interference).