Abstract
A method of joint clustering and precoding and a base station using the same are provided and applicable to a non-orthogonal multiple access (NOMA) system. The method includes: dividing four user equipments into a first cluster and a second cluster each consisting of two user equipments; forming a first cluster signal and a second cluster signal for simultaneous transmission at the base station; establishing a first precoding set and a second precoding set for the first cluster and the second cluster, respectively, by using channel state information between the base station and all the user equipments; selecting a first precoder from the first precoding set and a second precoder from the second precoding set; superposing the first cluster signal multiplied by the first precoder and the second cluster signal multiplied by the second precoder and broadcasting a resulting signal to the user equipments in the first and second cluster.