Uplink Nonorthogonal Multiple Access Technologies Toward 5G: A Survey

Table 4

Comparisons of NOMA receivers.

Receiver	Main character	Pros	Cons	Applications
MMSE-SIC	Reuses single-user receiver and SIC	Low complexity	Requires large SNR gaps among users	Almost all schemes, especially PD-NOMA
MPA/EPA	Symbol-level iterative detection	Near-ML symbol detection	Middle/high complexity	Sparse spreading NOMA
MPA-turbo/SIC	Iterative detection between symbol-level and bit-level	Better performance than MPA/EPA	High complexity	Sparse spreading NOMA
ESE-PIC	Iterative detection between symbol-level and bit-level	No requirement on sparsity	High complexity & hardware overhead	Especially bit-level NOMA