Low-Density Spreading Design Based on an Algebraic Scheme for NOMA Systems

In this letter, a code-domain nonorthogonal multiple access (NOMA) technique based on an algebraic design is studied. We propose improved low-density spreading (LDS) sequence projective geometry. terms of its bit error rate (BER) performance, our proposed LDS code set outperforms the existing designs over frequency-nonselective Rayleigh fading and additive white Gaussian noise (AWGN) channels. demonstrated that achieving best BER depends minimum distance.