Cooperated TDMA uplink based on hierarchically modulated Alamouti code

This paper proposes a user cooperation method for the TDMA uplink, which organizes cooperation among three "nearby" mobile terminals to achieve user cooperation diversity. The key technique in the proposal is the hierarchically modulated Alamouti code. Through emulating the Alamouti structure, the proposed method achieves some degrees of transmit diversity, while the hierarchical modulation enables an efficient data exchanging among the cooperating mobile terminals. We support our proposal with computer simulations under several typical cellular scenarios, which show that the proposed method can effectively combat with both macroscopic and microscopic fading, modelled as log-normal and Rayleigh, respectively.