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At the core of digital transformation of the manufacturing industry is the objective to unlock data at multiple points of the production system and produce insights to improve and optimize all aspects of the business operations. Tremendous advances in artificial intelligence and machine learning make it possible to analyze a vast volume of the field and production data and translate them into optimization decisions. Real-time access to the data complements efficient machine learning inference for timely and actionable insights. Flexible and re-configurable manufacturing also demands high-performance, pervasive, and low-la-tency communication links supporting mobility of workers, devices, and robots. Fifth Generation (5G) New Radio (NR) introduced basic support for Ultra Reliable and Low Latency Communication (urLLC) in Release-15 through intrinsic design features. Release-16 extends real-time capabilities of 5G NR to different verticals, addressing use cases in factory automation, the transport industry, and electrical power distribution. Wireless technologies such as 5G urLLC should co-exist with incumbent and emerging industrial Ethernet systems such as Time Sensitive Networking (TSN) in a heterogenous networking architecture. Hence, specification of interworking with TSN is also part of 3GPP Release-16. In this article, we discuss low-latency and high-reliability features supporting industrial automation, focusing on Release-16 design specifications. The interworking aspects with TSN and time synchronization accuracy limits are also highlighted, followed by performance evaluation of control and data traffic channels of 5G NR with respect to urLLC requirements.

This paper analyzes physical downlink control channel (PDCCH) for 5G New Radio (NR) technology defined as part of Rel-15 3GPP physical layer specifications. The particular combination of design elements makes NR PDCCH unique compared to the PDCCH or EPDCCH designs in LTE. We focus on the physical aspects of NR PDCCH structure and provide an in-depth summary of the design considerations, analysis of novel search space (SS) design options to better balance the PDCCH blind decoding (BD) and channel estimation capabilities, and performance evaluation of various transmission schemes and configurations supported by NR PDCCH. This study attests the flexibility and robustness of NR PDCCH design in addition to potential further enhancements for the scenarios with more stringent reliability requirements, e.g., URLLC applications.

In the 5th generation of mobile cellular systems, non-orthogonal multiple access (NOMA) is being considered as a potential candidate for uplink (UL) multiple access (MA) in addition to the basic orthogonal multiple access scheme in order to support various usage scenarios including small packet transmissions, support of a massive number of users , and low latency and high reliability services. In this paper, two simple multiple access schemes, low code rate spreading (LCRS) and short-sequence-based spreading multiple access (SSMA), with corresponding use of advanced receivers, are analyzed, demonstrating system capacity improvements compared to orthogonal multiple access (OMA) scheme. The robustness and gain of non-orthogonal multiple access scheme over orthogonal approaches are maximized when the packet size is small and suitable code rate is guaranteed.

We propose an enhanced precision channel state acquisition scheme for downlink Multi-User MIMO (MU-MIMO) transmission with a large number of transmit antennas at the base station. The proposed scheme is an attempt to harvest the Channel State Information (CSI) at the transmitter by incrementally improving the precision of the channel knowledge. We show how, in an LTE-Advanced system, CSI harvesting mechanism followed by the conventional Zero-Forcing Beam-Forming (ZFBF) results in improved MU-MIMO performance, relative to the current method for acquiring CSI at the transmitter. The proposed progressive CSI harvesting scheme is also shown to yield significant saving in terms of feedback overhead. The implications of the larger MIMO systems and higher MU-MIMO ranks, and sensitivity to higher mobility are also discussed.

Quality of Experience (QoE) has taken a center stage in the performance evaluation of multimedia delivery technologies. The Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) system is the latest generation of wireless cellular technology expected to deliver higher data rates and meet the burgeoning data demand. With the projected dominant share of video services in mobile traffic, providing satisfactory QoE to video users is a key objective for LTE system design. In this paper, we present a QoE-based evaluation methodology to assess the LTE system video capacity in terms of the number of unicast video consumers that can be simultaneously supported for a given target QoE. We define and use the notion of rebuffering outage capacity to quantify the video service capacity. Our evaluation further incorporates adaptive streaming, a promising technology for video delivery over wireless, and presents its consequent QoE-capacity tradeoff. The impact of QoE-based outage criteria is also investigated on the downlink video capacity. Finally, we propose a QoE-aware radio resource management (RRM) framework which allows the network operator to further enhance the video capacity. Our results demonstrate that there is a significant potential to optimize video capacity through QoE awareness both at the application level and radio access network (RAN) level.

One of the primary design goals of wireless multi-media communication systems is to optimize the quality of user experience. This metric is often quantified using the end-to-end distortion between the original source at the encoder and the reconstructed version of it at the destination. Considering this performance metric, optimal multimedia transmission schemes using joint source-channel coding (JSCC) for fading cognitive radio networks are studied in this paper. Different underlay transmission protocols, based on single- or multi-user receiver capabilities, are compared in terms of their average distortion performance, using an outage analysis. It is demonstrated that JSCC provides significant performance gains over goodput-maximizing schemes that rely on the optimality of source-channel separation, and that, for the scenarios evaluated, one of the proposed protocols with JSCC achieves average distortion performance very close to a lower bound obtained by ignoring the primary interference.

The problems of resource allocation and the characterization of cooperative behavior in a two-user fading multiple-access channel (MAC) in the presence of uncertainty about the channel state information at the transmitters (CSIT) are considered. Game-theoretic techniques are used to characterize cooperative behavior and obtain the system operation point from an individualistic perspective. A two-user bargaining problem formulation, with the utility function being defined as the average rate each user can achieve, is used to obtain a fair and efficient operating point. It is shown that for the conventional bargaining problem formulation, the Nash Bargaining Solution (NBS) is very sensitive to the CSIT, and hence may result in considerable performance degradation. A modified bargaining problem formulation, that does not require an explicit modeling of the actual CSIT error, is proposed to address this issue, and shown to provide significant robustness to the system.

In this paper, communication through an overlay cognitive radio network, wherein the cognitive ability of a secondary source needs to be acquired, i.e. the primary message may only be obtained by the cognitive source in a causal manner, is considered. A new achievable rate region for the discrete memoryless version of this network is derived using block Markov superposition coding (SPC), conditional rate-splitting, conditional Gel'fand-Pinkser (GP) binning, and cooperative relaying. This rate region is evaluated for Gaussian channels, and numerical results are presented to demonstrate the contributions of the various coding strategies, used in the proposed coding scheme, towards enlarging the achievable rate region.

In this paper, we evaluate the performance of various channel-sharing schemes in the forward link from a base station (BS) to several mobile stations (MSs). Simultaneous transmission (broadcasting) to all mobile stations using the entire available bandwidth is known to yield rates dominating any other channel-sharing technique for Gaussian channels. However, broadcasting is very complicated from an implementation point of view. We analyze and compare different channel-sharing techniques on the basis of the asymptotic minimum signal-to-noise ratio (SNR) per MS necessary at the BS to transmit to a certain set of MSs in a single cell at a common data rate. From our results we conclude that suboptimal but practical methods like two- or three-level superposition coding when used in conjunction with frequency division multiplexing perform sufficiently close to the optimum and hence, are good alternatives to the optimal broadcasting scheme.