# 5. Calculate Inset Feed Position (y0) for 50 Ohms # First, calculate edge impedance (approximate method) # G = W / (120 * lambda_0) is a simplification, here we use a standard empirical approximation for Rin # Rin_edge is typically calculated via radiation conductance G1 # Simplified standard formula for Rin at edge: lambda_0 = c / frequency_hz G1 = (W / (120 * lambda_0)) * (1 - ( (k0 * substrate_height) ** 2 ) / 24 ) # Approx conductance # k0 is wave number. For simplification in this text calculator, we use a standard approximation: Rin_edge = 90 * (dielectric_constant**2) / (dielectric_constant - 1) * (W/L) # Note: Rin_edge varies heavily. A common practical approximation for inset depth:
import math
# Constants c = 3e8 # speed of light in m/s microstrip patch antenna calculator
Theoretical calculations are a starting point. Real-world factors like connector soldering, substrate impurities, and copper roughness usually shift the frequency downward (making the antenna electrically larger). A common practical approximation for inset depth: import