Joint multiple access scheme using spatial and waveform signatures

A joint multiple access (MA) scheme is considered for uplink channels by using the code division MA (CDMA) and spatial division MA (SDMA) to increase the capacity (the number of users). In the joint MA system, a common spreading code can be assigned to different mobile stations. Hence, the number of users can be larger. Although some mobile stations have the same spreading code, the signals from the mobile stations can be detected by utilizing different spatial signatures arisen by using the antenna array. A multiuser detector is applied to detect the signals that are spread by the same spreading code. In order to properly assign the spreading codes to mobile stations, the spreading code assignment problem is also addressed in this paper.