This invention discloses a base station and a modulation method supporting lattice-partition-based non-orthogonal multiple access. The modulation method includes: modulating at least one most significant bit (MSB) of a weak user equipment (UE) to have a first transmission power; modulating at least one least significant bit (LSB) of the weak UE to have a second transmission power, wherein the second transmission power is less than the first transmission power; and modulating at least one second MSB of a strong UE to have a third transmission power, wherein the third transmission power is between the first transmission power and the second transmission power. |