Reflections at Boundaries

Higher Load Reflects a Positive Step

A load above the line impedance returns a same-sign reflected step. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

A higher load gives a positive coefficient

The load is 12 ohms and the line is 4 ohms, so the coefficient is 1 over 2.

Γ=12 − 412+4=12\Gamma={12\,-\,4\over 12+4}={1\over 2}
Higher load reflectionThe positive coefficient is computed from the load mismatch.incidentreflectedline 4 ohmload 12 ohmGamma 1/2in 12 Vback 6 V

The reflected step has the same sign

Half of the 12 volt incident step reflects as 6 volts.

V−=12⋅12 V=6 VV_{-}={1\over 2}\cdot 12\ \text{V}=6\ \text{V}
Positive reflected stepThe reflected label agrees with the coefficient.incidentreflectedline 4 ohmload 12 ohmGamma 1/2in 12 Vback 6 V