Nepers and dB

Nepers and dB

The SI units for the attenuation constant (a) are Nepers/meter

In practice, engineers like to express losses in transmission lines in units like dB/meter or (especially for coaxial cable) dB/100 ft.

Lossy Transmission Lines

Nepers and dB

What is the relationship between

Nepers per meter and dB per meter?

If a = 1 Np/m, what is the attenuation

in dB/m? in dB/100 ft?

Lossy Transmission Lines

Nepers and dB

Lossy Transmission Lines

10 1010log exp 2 20log 8.686

1 Np/m 8.686 dB/m

l ea

38.686 dB/m 25.4 10 m/in 1200 in/100 ft 264.7 dB/100 ft

1 Np/m 264.7 dB/100 ft