working in Octave (free version of Matlab), which is a bit easier than
Excel
>> s11mag = -29.6
s11mag = -29.600
>> s11ph = -77.1
s11ph = -77.100
>>
>> gamma = 10^(s11mag/20)
gamma = 0.033113
>> gamma = gamma*complex(cos(s11ph/180*pi),sin(s11ph/180*pi))
gamma = 0.0073925 - 0.0322774i
>> z = 50* ( 1+gamma)/(1-gamma)
z = 50.6383 - 3.2725i
This is the series form, and close to 50 ohms, as expected (a return
loss of 30dB is a good match)
Convert to parallel form
>> rs = real(z)
rs = 50.638
>> xs = imag(z)
xs = -3.2725
>> comterm = (rs/xs+xs/rs)
comterm = -15.538
>> rp=xs*comterm
rp = 50.850
>> xp = rs*comterm
xp = -786.84
>>
Which matches *neither* of the other versions.
And using a different way to convert series to parallel
>> Q = xs/rs
Q = -0.064626
>> xp = xs*(Q^2+1)/Q^2
xp = -786.84
>> rp=rs/(Q^2+1)
rp = 50.428
>>
Slightly different R - maybe it's a numerical precision thing Q^2 is
small
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