I’m seeking advice using enhanced response forwards error correction for a university project. The project involves taking raw S11 and S21 measurements with a HP8753 two port analyser and learning to apply error correction.

We’ve successfully achieved 1 port error correction for reflection measurements but having no luck with transmission measurements.

Last post I made, Dr Joel suggested I buy his book “Handbook of Microwave Component Measurements” which I did, and has proved to be a very informative and useful book.

To convey my question easily, I’ve adopted his style of notation.

Basically, we cannot get the equations for enhanced response correction to work. Upon further investigation, I cannot see how they possibly could.

We developed our own equations based on our own observations that work successfully with a range of loads, however I am perplexed as to why the equations published in several HP documents don’t appear to work.

*I’ve detailed the equations, procedures and results in the attached document, and I’m hoping someone can shed some light on the situation.*

Thanks in advance,

Josh

We’ve successfully achieved 1 port error correction for reflection measurements but having no luck with transmission measurements.

Last post I made, Dr Joel suggested I buy his book “Handbook of Microwave Component Measurements” which I did, and has proved to be a very informative and useful book.

To convey my question easily, I’ve adopted his style of notation.

Basically, we cannot get the equations for enhanced response correction to work. Upon further investigation, I cannot see how they possibly could.

We developed our own equations based on our own observations that work successfully with a range of loads, however I am perplexed as to why the equations published in several HP documents don’t appear to work.

*I’ve detailed the equations, procedures and results in the attached document, and I’m hoping someone can shed some light on the situation.*

Thanks in advance,

Josh

"Connect both ports together with a flush through and measure Transmission Tracking:ETF directly from S21."

BZZT! No, sorry, but thanks for playing 'make up your own error correction methods'

When you connect the thru, you are measuring the combination of ETF Plus the interaction of ESF and ELF.

The ETF term must be determined by a full 2 port calibration.

So I'll ask: why not do a full 2 port calibration? Why write your own? And, if you try to write your own, and your DUT is not m-f (hence, insertable) then you also have to deal with accounting for the effect of the non-zero thru. We do that in the 8753 with the adpater removal math. Seems like a lot of trouble to avoid using the built-in calibration.

If fact, to your second point, if ESF (source match) of the 8753 is zero, then S11 does NOT matter in the S21 math, as everything reflected is absorbed by the port 1 termination (ESF=0 implies perfect absorption of reflected signal) and one expects the effects of S11 to diminish with improved ESF.