Calcolatore Frequenza di Campionamento — Formula
## Understanding S-Parameters
Scattering parameters describe how RF energy propagates through a network.
### Parameter Meanings
- **S11**: Input return loss (reflection at port 1)
- **S21**: Forward transmission (gain or insertion loss)
- **S12**: Reverse transmission (isolation)
- **S22**: Output return loss (reflection at port 2)
### Conversion
**Linear = 10^(dB/20)** (for voltage/amplitude)
**dB = 20 x log10(Linear)**
For passive devices, S21 is negative (loss). For amplifiers, S21 is positive (gain).
Scattering parameters describe how RF energy propagates through a network.
### Parameter Meanings
- **S11**: Input return loss (reflection at port 1)
- **S21**: Forward transmission (gain or insertion loss)
- **S12**: Reverse transmission (isolation)
- **S22**: Output return loss (reflection at port 2)
### Conversion
**Linear = 10^(dB/20)** (for voltage/amplitude)
**dB = 20 x log10(Linear)**
For passive devices, S21 is negative (loss). For amplifiers, S21 is positive (gain).
Esempio Risolto
A filter with S11=-15 dB, S21=-0.5 dB, S12=-30 dB, S22=-20 dB.
- S11 linear: 10^(-15/20) = 0.1778
- S21 linear: 10^(-0.5/20) = 0.9441
- S12 linear: 10^(-30/20) = 0.03162
- VSWR at port 1: (1+0.1778)/(1-0.1778) = 1.43
- Insertion loss: 0.5 dB