Anritsu MS2024B - Appendix A - Formulas; A-1 Vector Network Analyzer Formulas

Vector Network Analyzer MG PN: 10580-00289 Rev. K A-1
Appendix A — Formulas
A-1 Vector Network Analyzer Formulas
The following formulas can be used with the Vector Network Analyzer (VNA Master and
LMR Master).
Reflection Coefficient
Reflection coefficient is the ratio of the amplitude of the reflected wave to the amplitude of
incident wave.
Return Loss
VSWR
Smith Chart
Inverted Smith Chart
Electrical Length
The length of the cable as seen by the electrical signal. The electrical length is always greater
than 1 for practical dielectric materials.
Reflection Coefficient ρ=
where: 0 ρ 1≤≤
Return Loss (dB) 20 ρlog–=
where: 0 Return Loss ∞<≤
VSWR
1 ρ+()
1 ρ–()
------------------=
where: 1 VSWR ∞<≤
Smith Chart: zrjx+=
ρ
z1–()
z1+()
-----------------=
Inverted Smith Chart: Y GjB+=
Electrical Length L=
el
L
mech
ε×=