One of the key requirements for fifth-generation (5G) cellular networks istheir ability to handle densely connected devices with different quality ofservice (QoS) requirements. In this article, we present multi-service orientedmultiple access (MOMA), an integrated access scheme for massive connectionswith diverse QoS profiles and/or traffic patterns originating from bothhandheld devices and machine-to-machine (M2M) transmissions. MOMA is based ona) stablishing separate classes of users based on relevant criteria that gobeyond the simple handheld/M2M split, b) class dependent hierarchical spreadingof the data signal and c) a mix of multiuser and single-user detection schemesat the receiver. Practical implementations of the MOMA principle are providedfor base stations (BSs) that are equipped with a large number of antennaelements. Finally, it is shown that such amassive-multiple-input-multiple-output (MIMO) scenario enables the achievementof all the benefits of MOMA even with a simple receiver structure that allowsto concentrate the receiver complexity where effectively needed.
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