The Reflection Attenuator conversion calculator determines the two resistor values required for a reflection attenuator network. This type of attenuator provides a precise level of attenuation while maintaining impedance matching, making it ideal for RF calibration, testing, and controlled signal level adjustment.
Formulas
R1(Ω) < Zo = Zo * [ (10^(dB/20) – 1) / (10^(dB/20) + 1) ]
R1(Ω) > Zo = Zo * [ (10^(dB/20) + 1) / (10^(dB/20) – 1) ]
Formula Explanation
- R1<Zo is the resistor value smaller than the system impedance.
- R1>Zo is the resistor value larger than the system impedance.
- Zo is the characteristic impedance of the circuit, often 50 Ω or 75 Ω.
- dB is the desired attenuation level in decibels.
- The formulas maintain a balanced impedance and symmetrical reflection response across the network.
Uses of this calculator
- Designing reflection attenuators for precision RF applications.
- Maintaining impedance matching in attenuated circuits.
- Calibrating instruments and test setups with known signal reduction.
- Implementing symmetrical attenuation in RF or microwave networks.
What are the resistor values for a 10 dB reflection attenuator with 50 Ω impedance?
Input: Attenuation = 10 dB, Zo = 50 Ω
Output:
- R1<Zo = 50 * [ (10^(10/20) – 1) / (10^(10/20) + 1) ] = 50 * (2.162 / 4.162) = 50 * 0.519 = 25.95 Ω
- R1>Zo = 50 * [ (10^(10/20) + 1) / (10^(10/20) – 1) ] = 50 * (4.162 / 2.162) = 50 * 1.924 = 96.2 Ω
- R1<Zo = 25.95 Ω, R1>Zo = 96.2 Ω