A method, comprising: sending, by an access point, AP, to a user equipment, UE, a multiple access block, MAB, region assignment via a first signaling to configure a MAB region, wherein the MAB region corresponds to a first frequency partition of a plurality of frequency partitions of a carrier spectrum band, the MAB region is associated with a first MAB type of multiple MAB types, and the first MAB type comprises a first sub-carrier spacing and a first symbol duration; and communicating, by the AP with the UE, a first OFDM signal within the first frequency partition using the first sub-carrier spacing and a first symbol duration; wherein the multiple MAB types comprise a second MAB type used for communicating a second OFDM signal within a second MAB region corresponding to a second frequency partition of the plurality of frequency partitions of the carrier spectrum band, the second MAB region is associated with the second MAB type, and the second MAB type comprises a second sub-carrier spacing and a second symbol duration for communicating the second OFDM signal, the method being characterized in that the first sub-carrier spacing is a two or four multiple of the second sub-carrier spacing, and the second symbol duration is a two or four multiple of the first symbol duration; wherein the first symbol duration equals a sum of a first useful symbol length and a first cyclic prefix, CP, length, the second symbol duration equals a sum of a second useful symbol length and a second CP length, the second useful symbol length is a two or four multiple of the first useful symbol length, and the second CP length is a two or four multiple of the first CP length. sending, by an access point, AP, to a user equipment, UE, a multiple access block, MAB, region assignment via a first signaling to configure a MAB region, wherein the MAB region corresponds to a first frequency partition of a plurality of frequency partitions of a carrier spectrum band, the MAB region is associated with a first MAB type of multiple MAB types, and the first MAB type comprises a first sub-carrier spacing and a first symbol duration; and communicating, by the AP with the UE, a first OFDM signal within the first frequency partition using the first sub-carrier spacing and a first symbol duration; wherein the multiple MAB types comprise a second MAB type used for communicating a second OFDM signal within a second MAB region corresponding to a second frequency partition of the plurality of frequency partitions of the carrier spectrum band, the second MAB region is associated with the second MAB type, and the second MAB type comprises a second sub-carrier spacing and a second symbol duration for communicating the second OFDM signal, the method being characterized in that the first sub-carrier spacing is a two or four multiple of the second sub-carrier spacing, and the second symbol duration is a two or four multiple of the first symbol duration; wherein the first symbol duration equals a sum of a first useful symbol length and a first cyclic prefix, CP, length, the second symbol duration equals a sum of a second useful symbol length and a second CP length, the second useful symbol length is a two or four multiple of the first useful symbol length, and the second CP length is a two or four multiple of the first CP length.