FAQ

How Accurate Is RF View Circuit Simulation?

RF View circuit simulation accuracy depends on component models. S2P DUT blocks are exact; ideal L/C are exact for their stated values; Real Match (Murata) gives high accuracy. Comparison guide.

Answer Depends on Component Model Type

Element TypeSimulation AccuracyNotes
S2P DUT block (measured)Exact (to VNA accuracy)Uses real measured VNA data — no model error
Ideal R/L/C elementsExact for stated valueNo Q, no parasitics — optimistic
Ideal T-line (Z₀, θ)Exact for ideal TLNo dispersion, no loss — optimistic
Microstrip T-line (W, L, εr)±1% typicalHammerstad-Jensen formula accuracy
Real Match (Murata data)High accuracy to SRFUses manufacturer-measured component S2P

When Ideal Component Simulation Is Sufficient

  Frequency < 500 MHz:
    Typical SMD inductor Q > 100 → ideal model gives <0.1 dB error
    Component SRF typically > 5 GHz → ideal model valid at UHF

  500 MHz to 2 GHz:
    Inductor Q drops to 40–80 → ideal model underestimates IL by 0.2–0.5 dB
    Use Real Match for more accurate pre-assembly prediction

  Above 2 GHz:
    SRF of 0402 SMD inductors approaches → ideal model can be very wrong
    Always use Real Match or measured S2P component data above 2 GHz

Accuracy Example: 900 MHz L-Network

  Design: shunt 6.8 pF C0G + series 3.5 nH inductor for 10 → 50 Ω match

  Ideal simulation: S11 = −18 dB at 900 MHz (perfect)
  Real Match (Murata LQP 3.3nH, C0G 6.8pF):
    S11 = −14.5 dB at 900 MHz (realistic, includes Q and ±tolerance)
  After PCB build (measured):
    S11 = −12.8 dB (additional layout parasitics)

  Lesson: ideal gives optimistic result; Real Match closer to reality;
          measurement after PCB build reveals remaining layout effects.
RF View Best Practice: Use ideal elements for initial exploration, switch to Real Match for pre-assembly prediction, then compare with VNA measurement after assembly to identify layout effects. Free on Android.

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