The most important characteristic of FBMC is that at a given FFT length it can perform much better than the corresponding OFDM. OFDM composes a rectangular window, the sub carrier is based on the sinc function, side lobe attenuation has a very gradual drop about 20db. We can use FBMC by managing the filter length of 3 which will be the same as but FBMC will have a very sharp drop until -100db as you can see in figure 28. Without too much use of the guard length we can pack the same frequency adjacent together. This implies the main benefit of FBMC module being proposed.
