The adapting device may select an access mode in accordance with the mapping rules to meet the access mode criteria, the communications system information, and the UE information (block 620). The adapting device may select the access mode out of a plurality of access modes. As an illustrative example, the adapting device may have a list of the plurality of access modes and the adapting device may select the access mode out of the plurality of access modes. The adapting device may select the access mode from the plurality of access modes by considering the access mode criteria, the communications system information, and the UE information. As an illustrative example, if the UE is a legacy UE with no SCMA capability, the adapting device may select OFDMA as the access mode. Similarly, if the UE is SCMA capable, the adapting device may consider access mode criteria, such as link-budget, coverage, and the like, to select the access mode. Detailed discussions of example access mode selection techniques are presented below.

The adapting device may determine the communications system parameters, e.g., SCMA parameters, from the selected access mode in accordance with the mapping rules (block 622). The adapting device may use mapping rules, such as the example mapping rules shown in Table 3, to determine values for communications system parameters from the selected access mode. As an illustrative example, if the selected access mode for a specified type of UE is to increase the coverage area for the UE, the adapting device may use mapping rule #7 shown in Table 3 and increase parameter N only or both parameters N and K while limiting parameter J and consider complexity impacts, since increasing parameter N improves processing and multi-dimensional gain of SCMA codebooks.