A communication method of simultaneously transmitting a plurality of signals to a plurality of user groups using at least one antenna group in a communication system, comprising: assigning the at least one antenna group to the plurality of user groups; generating a user group signal by combining user signals for each user group; combining a plurality of user group signals; and transmitting the combined user group signal to a plurality of users belonging to the plurality of user groups using the at least one antenna group, wherein the generating of the user group signal comprises combining a plurality of user signals for each user group using at least one user multiplexing method among a power division multiplexing method, a code division multiplexing method and a spatial division multiplexing method, wherein the combining of the plurality of user group signals comprises combining a plurality of user group signals, to each of which a plurality of user signals have been combined, using at least one group multiplexing method among a power division multiplexing method, a code division multiplexing method, and a spatial division multiplexing method, wherein the plurality of user group signals are different from each other in terms of at least one of channel condition factors, service condition factors, user condition factors, and transmission condition factors, wherein the channel condition factors include at least one of quality factors related to channel characteristics, and quality factors related to spatial characteristics; wherein the service condition factors include at least one of Quality-of- Service, QoS, a traffic class, and a location; wherein the user condition factors include at least one of the cost, the terminal capability, and a security level; and wherein the transmission condition factors include at least one of the user multiplexing method, a group combining weight vector, an antenna group, a duplexing method, a multiple access method, a modulation method, a channel coding method, and a Multiple-Input Multiple-Output, MIMO, transmission method. assigning the at least one antenna group to the plurality of user groups; generating a user group signal by combining user signals for each user group; combining a plurality of user group signals; and transmitting the combined user group signal to a plurality of users belonging to the plurality of user groups using the at least one antenna group, wherein the generating of the user group signal comprises combining a plurality of user signals for each user group using at least one user multiplexing method among a power division multiplexing method, a code division multiplexing method and a spatial division multiplexing method, wherein the combining of the plurality of user group signals comprises combining a plurality of user group signals, to each of which a plurality of user signals have been combined, using at least one group multiplexing method among a power division multiplexing method, a code division multiplexing method, and a spatial division multiplexing method, wherein the plurality of user group signals are different from each other in terms of at least one of channel condition factors, service condition factors, user condition factors, and transmission condition factors, wherein the channel condition factors include at least one of quality factors related to channel characteristics, and quality factors related to spatial characteristics; wherein the service condition factors include at least one of Quality-of- Service, QoS, a traffic class, and a location; wherein the user condition factors include at least one of the cost, the terminal capability, and a security level; and wherein the transmission condition factors include at least one of the user multiplexing method, a group combining weight vector, an antenna group, a duplexing method, a multiple access method, a modulation method, a channel coding method, and a Multiple-Input Multiple-Output, MIMO, transmission method.