Coaxial Waveguide – TEM Mode Visualizer
Transverse electromagnetic mode.
Mode: TEM | No cutoff | Propagating
Electric Field (E) – Cross‑section
Radial E field lines.
Magnetic Field (H) – Cross‑section
Azimuthal H field lines.
E‑field in x‑z plane (y=0)
Axial variation (Ex, Ez).
H‑field in x‑z plane (y=0)
(Hx, Hz).
Surface Currents on Inner & Outer Conductors
Magnitude vs azimuth (inner conductor).
📐 TEM Field Equations
Er = V0 / (r ln(b/a)) e-jβz
Hφ = I0 / (2πr) e-jβz
β = ω√(με)
Hφ = I0 / (2πr) e-jβz
β = ω√(με)
📝 Description & Applications
Coaxial cables are widely used for RF transmission. They support TEM mode, which has no cutoff frequency.
Applications: Antenna feeds, interconnects, test equipment.
Advantages: Broadband, flexible.
Disadvantages: Higher loss at high frequencies, power handling limited.
💡 Interview Questions
Why does a coaxial cable have no cutoff frequency for TEM mode?
What determines the characteristic impedance of a coaxial line?