Cavity Resonance Frequency Calculator

This calculator determines the resonance frequency of a rectangular microwave cavity based on its dimensions and material properties. It helps in designing resonant cavities used in filters, oscillators, and microwave circuits.

Formula

f_mnp = ( c / ( 2 × √(ε_r × μ_r) ) ) × √( (m/a)² + (n/b)² + (p/h)² )

Formula Explanation

• c = 3 × 10¹¹ mm/s (speed of light)
• ε_r = relative permittivity
• μ_r = relative permeability
• m, n, p = mode numbers
• a, b, h = cavity dimensions in mm, cm, or inch

Example

Input: a = 40 mm, b = 30 mm, h = 20 mm, ε_r = 1, μ_r = 1, mode (1,1,0)

Result: f₁₁₀ ≈ 6.25 GHz

Who uses it

Useful for RF and microwave engineers designing resonant cavities, filters, and oscillators in communication systems.