A flexible multirate CDMA concept with multiuser detection

We propose a multirate coding and modulation concept for third generation wireless communication systems employing code division multiple access. The concept consists of a flexible coding method in which multiple services, with different quality requirements, can be multiplexed in one frame, and in which the data rate can vary dynamically on a frame by frame basis. Furthermore, in order to maximize the capacity we design the modulation so that multiuser detection can be efficiently implemented. Multiuser detection is used for providing acceptable capacity in a cell with multiple users with variable data rates. Simulation results related to the proposed multirate multiuser scheme are presented