Abstract:

In this paper, a new transmit diversity scheme is proposed for cooperative pseudo-non-orthogonal multiple access (Pseudo-NOMA) without assuming full channel state information at the transmitter (CSIT). To support two users under the nearfar user pairing constraint, a distributed cyclic delay diversity (dCDD) scheme is adapted into NOMA by dividing a set of remote radio heads (RRHs) into two groups for multiple cyclicprefixed single carrier transmissions. To maximize a far user’s rate and two users’ sum rate over independently but nonidentically distributed frequency selective fading channels and under near-far user pairing constraint, we first derive the closedform expressions for the rate of two users with full CSIT. Considering that only partial CSIT is available, a new RRH assignment and power allocation scheme is proposed for dCDDPseudo-NOMA. For various simulation scenarios, the provided link-level simulations verify that the superior rate can be achieved by dCDD-Pseudo-NOMA over the traditional orthogonal multiple access with dCDD and dCDD-Conventional-NOMA that uses the superimposed signals. Furthermore, the proposed RRH assignment and power allocation scheme makes dCDD-PseudoNOMA achieves almost the same rate as that of ideal dCDDPseudo-NOMA which requires full CSIT.