Whilst there is freedom to design a structure that is not fixed to the existing 9 bands or band-widths, the possible approaches we present here are focused on having 9 or 12 bands.
Er bod rhyddid i lunio strwythur nad yw ynghlwm wrth y 9 band presennol na lled y bandiau, mae'r dulliau posibl a gyflwynwn yma yn canolbwyntio ar gael 9 neu 12 band.