I responded to one of your questions
recently. I said to consider the SRF of your
blocking cap. However, SRF is not your limiting
factor for a blocking cap. Impedance is what
Keep the size of your cap
is close to the width of transmission line.
I have used 10nF caps up to 6GHz with no problems.
If I go by your reasoning the I believe
that SRF should also not be the limiting factor
for the RF Choke/inductor used in Bias Tees for
Biasing amplifier. There also i should consider
recently I came across a
part whose data sheet says that it works from DC
to 1 GHz. When I did simulations using the S-parameter
file for the part, I found that the Low frequency
performance was not as given in the data-sheet.
When contacted the support engineers of the part
vendor informed that the measurement was taken using
Broad band Bias Tees at the output port. They suggested
that to get the desired performance I can use a
300uH Biasing Inductor with SRF >300 MHz. I spent
considerable time searching for a surface mountable
inductor with that high SRF for a 300uH inductor.
The best I got was 7 MHz. Although Simulations using
the S-parameter files showed not much degradation
in performance beyond 7 MHz, I don't know how the
measured result would be