In Wes Hayward's book "Introduction to Radio Frequency Design" on page
116, the voltage reflection coefficient is given as gamma = V-/V+ = (z-1)/(z+1) where z is the normalized impedance, Zin/Z_o. As an example, the author then takes a circuit comprised of a 2 volt source into a voltage divider to calculate the output voltage based on reflected voltage waves. For example, with a source resistance of 1 ohm and a load resistance of 0.5 ohm, gamma = (0.5 -1)/(0.5 +1) = -0.333. The forward wave is said to be 1 and the reverse wave is -0.333 leaving a sum of 0.667, which is the same thing you would get using the voltage divider equation: (2*0.5)/(0.5+1) = 0.667.
My point of confusion is that this example only seems to work with a source voltage of 2 volts. Why does a 2 volt supply cause the forward wave to be 1? I'm probably missing something obvious, but could use some insight.