Microstrip Mitred Bend Calculator

The Microstrip Mitred Bend Calculator determines the optimal miter dimensions for a 90° microstrip bend to minimize reflection and maintain characteristic impedance continuity. Proper mitering ensures smooth signal transition and reduces impedance mismatch in high-frequency PCB layouts.

Formulas

D = W * √2

X = W * √2 * (0.52 + 0.65 * e−1.35 * (W / h))

A = X * √2 − W

Where:

  • W = Width of the microstrip line
  • h = Height (thickness) of the substrate
  • D = Diagonal length of the mitered square corner
  • X = Effective diagonal compensation distance
  • A = Adjusted (compensated) length to maintain impedance at the bend

Applications

  • Used in PCB design to minimize reflection at right-angle bends.
  • Ensures consistent characteristic impedance across microstrip transitions.
  • Improves signal integrity in RF and microwave circuit layouts.
  • Commonly used in microwave filters, couplers, and antenna feed networks.

Example Calculation

Input: W = 1112 mil, h = 22 mil

Results:

  • D = 1112 × √2 = 1572.61 mil
  • X = 1112 × √2 × (0.52 + 0.65 × e−1.35 × (1112 / 22)) ≈ 817.75 mil
  • A = 817.75 × √2 − 1112 ≈ 44.48 mil