Low Complexity Resource Allocation Based on Linear Search for Frequency Domain Non-Orthogonal Multiple Access

This paper proposes low complexity resource allocation based on a linear search for frequency domain non-orthogonal multiple access based on the low-density signature (LDS). Two algorithms are proposed for the linear search. The application of the linear search makes the proposed resource allocation implemented with lower and fixed computational complexity. The performance of the non-orthogonal access based on the linear search is evaluated by computer simulation. One of the proposed linear search algorithm makes the non-orthogonal multiple access achieve 5 dB better BER performance than the other when the overloading ratio is set to 2. The complexity of the non-orthogonal access based on the proposed linear search algorithm is approximately half as much as that of the conventional low complexity resource allocation when the overloading ratio is 2, if the complexity is evaluated in terms of the number of additions.