Hi.

I've evaluated Flexible Balance Analysis in SpectreRF
since "MMSIM 6.0 USR1" and "MMSIM 6.0 USR2".
These were very inferior than HB-Ana of ADS
and helpful only for very small circuits.
Of course FB-QPSS was far helpful than shooting-QPSS.
So I concluded that FB-Analysis of SpectreRF is very inferior
than HB-Ana of ADS, so we've not adopted it until now.

I've expected remarkable improvement in MMSIM6.1.
But my conclusion was never changed.

Cadence have continued to claim that
"Shooting Newton of SpectreRF can simulate very large and high nonlinear circuits than HB analysis".
But ............

My log envelope detector circuit(RSSI) is composed of limiter, rectifier, bias etc.
Circuit size is fairly large. So it takes much time even for DC analysis.
Relative new ADS HB can succeed for such large and high nonlinear circuits.
but I think older ADS(e.g. ADS2004) couldn't succeed.

Of course, Shooting of SpectreRF resulted in fail after long long time
and with extraordinary computer memory consumption.

Other than this, there are many circuits where Flexible Balance Analysis of SpectreRF
can't converge or succeed while Agilent ADS can give reasonable results.

For Simple low IF receiver with one RF input and one direct LO input,
FB-Analysis could give reasonable results quickly.

But with frequency divider before mixer local input, FB-Analysis couldn't give
reasonable results, here iteration of FB reached to upper limits.
So I set "maxperiods" parameter which is available also for FB-Analysis.
Of course, I set "freqdivide" parameter and tried to increase "oversample" parameter.
But FB couldn't converge even though it reached to upper iteration limits.