Some definitions what is IFT and how it is calculated and what formation it produce.
MLADEN : Now the smoothed RSI " Inverse Fisher Transform" with a difference that it uses the improved Rainbow WMA (i decided to call it that way since i think that it is much better name and having in mind who actually found that way of calculating ... ) the rest is the same - in short it is an Ehlers" inverse fisher transform of a zero lag smoothed RSI of a rainbow wma (interesting definition,is not it ) ... also you might want play with parameters - i did use the default 4 for rsi length but longer ones to tend to look good too (see the second picture with rsi period 15)