A Multi-Service Oriented Multiple-Access Scheme For M2M Support in   Future LTE
  We propose a novel multiple-access technique to overcome the shortcomings of the current proposals for the future releases of Long-Term Evolution (LTE). We provide a unified radio access system that efficiently and flexibly integrates both traditional cellular services and machine-to-machine (M2M) connections arising from Internet-of-Things (IoT) applications. The proposed solution, referred to as multi-service oriented multiple access (MOMA), is based on a) establishing separate classes of users using relevant criteria that go beyond the simple handheld-IoT device split, b) service-dependent hierarchical spreading of the data signals and c) a mix of multiuser and single-user detection schemes at the receiver. Signal spreading in MOMA allows to handle densely connected devices with different quality-of-service (QoS) profiles and at the same time its flexible receiver structure allows to allocate the receiver computational resources to the connections that need it most. This yields a scalable and efficient use of the available radio resources and a better service integration. While providing significant advantages for key future communications scenarios, MOMA can be incorporated into LTE with a limited impact on the protocol structure and the signaling overhead. 
Nassar Ksairi, Stefano Tomasin, M\'erouane Debbah
cs.IT math.IT