Reduced Complexity Resource Allocation For Frequency Domain Non-orthogonal Multiple Access

This paper proposes low complexity resource allocation in frequency domain non-orthogonal multiple access where many devices access with a base station. The number of the devices is assumed to be more than that of the resource for network capacity enhancement, which is demanded in massive machine type communications (mMTC). This paper proposes two types of resource allocation techniques, which are named as "CGVS" and "LLRVS", all of which are based on the MIN-MAX approach. CGVS seeks for nicer resource allocation with only channel gains, while LLRVS applies the message passing algorithm (MPA) for better resource allocation. The proposed resource allocation techniques are evaluated by computer simulation in frequency domain non-orthogonal multiple access. Whereas LLRVS achieves only 0.1dB better performance than CGVS in the multiple access with the overloading ratio of 1.5 at the BER of 10(-4), CGVS can be implemented with 10(-5) smaller computational complexity than LLRVS. CGVS attains a gain of about 10dB at the BER of 10(-4) in the multiple access with the overloading ration of 2.0. The complexity of CGVS is 10(-16) as small as the conventional technique.