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The expected growth in the mobile video demand over the broadband cellular networks is one of the key factors driving the wireless industry to develop fifth generation of network technology. This scenario is fueling the need for group-oriented services (i.e., multicast and broadcast) in order to efficiently manage the radio resources, and consequently, grant different groups of users simultaneous access to the same multimedia content with differentiated quality of service (QoS). The evolved Multimedia Broadcast Multicast Service (eMBMS), standardized by the Third Generation Partnership Project (3GPP), is one of the technologies likely to be extended to 5G systems with the aim of addressing Point-to-Multipoint services. In addition, Non-Orthogonal Multiplexing Access (NOMA) techniques are being also considered as a driver to increase the efficient use of the spectrum in multi-user environments with asymmetric data delivery. The present article proposes the joint use of subgrouping multicast techniques and NOMA, in an eMBMS-like scenarios. Performance is evaluated in envisaged 5G environments, where different quality video services are delivered to a group of users interested in the same contents.

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Industry 4.0 and Industrial Internet refer to the expected revolution in production, utility management and, in general, fully automated, interconnected and digitally managed industrial ecosystems. One of the key enablers for Industry 4.0 lies on reliable and timely exchange of information and large scale deployment of wireless communications in industry facilities. Wireless will bring solutions to overcome the main drawbacks of the current wired systems: lack of mobility, deployment costs, cable damage dependency and scalability. However, the strict requirements in reliability and latency of use cases such as Factory Automation (FA) and Process Automation (PA) are still a major challenge and a barrier for massive deployment of currently available wireless standards. This paper proposes a PHY/MAC wireless communication solution for FA and PA based on Non-Orthogonal Multiple Access (NOMA) in combination with the 802.11n standard. The communication system proposed aims at delivering two different sets of services. The first service class is composed of Critical Services (CS) with strict restrictions in reliability and latency. The same communication system should convey also a second group of services, referred as Best Effort (BE) with more relaxed boundary conditions. The proposal theoretical background, a detailed transmission-reception architecture, the physical layer performance and the MAC level system reliability are presented in this paper. The solution provides significantly better reliability and higher flexibility than TDMA systems, jointly with a predictable control-cycle latency.

Cloud Transmission (Cloud Txn) System is a flexible multi-layer system that uses spectrum overlay technology to simultaneously deliver multiple program streams with different characteristics and robustness for different services (mobile TV, HDTV and UHDTV) in one RF channel. The transmitted signal is formed by superimposing a number of independent signals at desired power levels, to form a multilayered signal. The signals of different layers can have different coding, bit rate, and robustness. For the top layer, system parameters are chosen to provide very robust transmission that can be used for high speed mobile broadcasting service to portable devices. The bit rate is traded for more powerful error correction coding and robustness so that the Signal to Noise Ratio (SNR) threshold at the receiver is a negative value in the range of -2 to -3 dB. The top layer is designed to withstand combined noise, co-channel interference and multipath distortion power levels higher than the desired signal power. The lowerlayer signal can be DVB-T2 signal or other newly designed system to deliver HDTV/UHDTV to fixed receivers. The system concept is open to technological advances that might come in the future: all new technologies, BICM/Non Uuniform-QAM, rotated constellations, Time Frequency Slicing or MIMO techniques can be implemented in the Cloud Txn lower (high data) rate layer. The main focus of this paper is to thoroughly describe the performance of this newly presented Cloud Transmission broadcasting system.

Cloud transmission (Cloud-Txn) with LayerDivision-Multiplexing (LDM) was proposed as a candidate Physical Layer (PHY) technology for next generation digital TV broadcasting system. This paper presents a fundamental analysis on the channel capacity allocation among the different layers of a LDM-based transmission system. The analysis reveals that, for delivering fixed and mobile TV services in the same RF channel, by controlling the power allocation among the layers, the LDM-based system provides much better efficient usage of the spectrum as compared to the single-layer Time-DivisionMultiplexing (TDM) or Frequency-Division-Multiplexing (FDM)-based systems. The spectrum efficiency of LDM allows the simultaneous delivery of a high-data-rate UHDTV service and a mobile HDTV service within a single 6 MHz channel.

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