Joint uplink SCMA codebook design for correlated fading channels

Abstract

Sparse Code Multiple Access (SCMA) is currently one of the most intensively investigated Multicarrier Non-Orthogonal Multiple Access (NOMA) technology for 5G wireless communication system. Careful design of SCMA codebook is one of the major performance criteria of uplink SCMA systems. We took the challenge of tackling SCMA Codebook design problem in correlated Rayleigh fading channels. We propose a novel joint codebook design approach followed by a new signal model, where the design problem is posed as a Quadratically Constrained Quadratic Program (QCQP) which is dealt using Matrix-lifting Semidefinite Relaxation (MSDR). Extensive numerical simulations are presented to provide the validity of proposed codebook comparing with some other well known designs.