Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> For the Internet of Things to become a reality needs a set of technologies to support the communication of and object. For short range communication this is solved, but for large range several candidates are possible. The usage of mobile networks has been as the only solution until two years ago that the so called LPWA solutions appeared. Among the different solutions proposed, in addition to Sigfox, already in use, LoRa appears as a good solution that needs to be studied in more detail. <s> BIB001 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> Low power and long range machine-to-machine (M2M) communication techniques are expected to provide ubiquitous connections for the wireless devices. In this paper, three major low power and long range M2M solutions are surveyed. The first type of solutions is referred to as the low power wide area (LPWA) network. The design of the LPWA techniques features low cost, low data rate, long communication range, and low power consumption. The second type of solutions is the IEEE 802.11ah which features higher data rates using a wider bandwidth than the LPWA-based solutions. The third type of solutions is operated under the cellular network infrastructure. Based on the analysis of the pros and cons of the enabling technologies of the surveyed M2M solutions, as well as the corresponding deployment strategies, the gaps in knowledge are identified. The paper also presents a summary of the research directions for improving the performance of the surveyed low power and long range M2M communication technologies. <s> BIB002 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> Low power wide area (LPWA) networks are attracting a lot of attention primarily because of their ability to offer affordable connectivity to the low-power devices distributed over very large geographical areas. In realizing the vision of the Internet of Things, LPWA technologies complement and sometimes supersede the conventional cellular and short range wireless technologies in performance for various emerging smart city and machine-to-machine applications. This review paper presents the design goals and the techniques, which different LPWA technologies exploit to offer wide-area coverage to low-power devices at the expense of low data rates. We survey several emerging LPWA technologies and the standardization activities carried out by different standards development organizations (e.g., IEEE, IETF, 3GPP, ETSI) as well as the industrial consortia built around individual LPWA technologies (e.g., LoRa Alliance, Weightless-SIG, and Dash7 alliance). We further note that LPWA technologies adopt similar approaches, thus sharing similar limitations and challenges. This paper expands on these research challenges and identifies potential directions to address them. While the proprietary LPWA technologies are already hitting the market with large nationwide roll-outs, this paper encourages an active engagement of the research community in solving problems that will shape the connectivity of tens of billions of devices in the next decade. <s> BIB003 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> Abstract By 2020, more than twenty five billion devices would be connected through wireless communications. In accordance with the rapid growth of the internet of things (IoT) market, low power wide area (LPWA) technologies have become popular. In various LPWA technologies, narrowband (NB)-IoT and long range (LoRa) are two leading technologies. In this paper, we provide a comprehensive survey on NB-IoT and LoRa as efficient solutions connecting the devices. It is shown that unlicensed LoRa has advantages in terms of battery lifetime, capacity, and cost. Meanwhile, licensed NB-IoT offers benefits in terms of QoS, latency, reliability, and range. <s> BIB004 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> Internet of Things (IoT) technology has attracted much attention in recent years for its potential to alleviate the strain on healthcare systems caused by an aging population and a rise in chronic illness. Standardization is a key issue limiting progress in this area, and thus this paper proposes a standard model for application in future IoT healthcare systems. This survey paper then presents the state-of-the-art research relating to each area of the model, evaluating their strengths, weaknesses, and overall suitability for a wearable IoT healthcare system. Challenges that healthcare IoT faces including security, privacy, wearability, and low-power operation are presented, and recommendations are made for future research directions. <s> BIB005 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> The deployment of Internet of Things (IoT) devices and services is accelerating, aided by ubiquitous wireless connectivity, declining communication costs, and the emergence of cloud platforms. Most major mobile network operators view machine-to-machine (M2M) communication networks for supporting IoT as a significant source of new revenue. In this article, we discuss the need for wide-area M2M wireless networks, especially for short data packet communication to support a very large number of IoT devices. We first present a brief overview of current and emerging technologies for supporting wide area M2M, and then using communication theory principles, discuss the fundamental challenges and potential solutions for these networks, highlighting tradeoffs and strategies for random and scheduled access. We conclude with recommendations for how future 5G networks should be designed for efficient wide-area M2M communications. <s> BIB006 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> In 3GPP LTE Release 13, Narrowband Internet of Things (NB-IoT) was standardized for providing wide-area connectivity for massive machine-type communications for IoT. In LTE Release 14, NB-IoT was further developed to deliver enhanced user experience in selected areas through the addition of features such as increased positioning accuracy, increased peak data rates, the introduction of a lower device power class, improved non-anchor carrier operation, multicast, and authorization of coverage enhancements. In this article, we provide an overview of these features introduced for NB-IoT in LTE Release 14. An analysis is given on the applicability of these features and their benefits to enhance the NB-IoT radio access technology. <s> BIB007 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> Low-power wide area networking technology offers long-range communication, which enables new types of services. Several solutions exist; LoRaWAN is arguably the most adopted. It promises ubiquitous connectivity in outdoor IoT applications, while keeping network structures and management simple. This technology has received a lot of attention in recent months from network operators and solution providers. However, the technology has limitations that need to be clearly understood to avoid inflated expectations and disillusionment. This article provides an impartial and fair overview of the capabilities and limitations of LoRaWAN. We discuss those in the context of use cases, and list open research and development questions. <s> BIB008 </s> Low Power Wide Area Networks: A Survey of Enabling Technologies, Applications and Interoperability Needs <s> 3) RANDOM PHASE MULTIPLE ACCESS (RPMA) <s> Abstract By 2020, more than 50 billion devices will be connected through radio communications. In conjunction with the rapid growth of the Internet of Things (IoT) market, low power wide area networks (LPWAN) have become a popular low-rate long-range radio communication technology. Sigfox, LoRa, and NB-IoT are the three leading LPWAN technologies that compete for large-scale IoT deployment. This paper provides a comprehensive and comparative study of these technologies, which serve as efficient solutions to connect smart, autonomous, and heterogeneous devices. We show that Sigfox and LoRa are advantageous in terms of battery lifetime, capacity, and cost. Meanwhile, NB-IoT offers benefits in terms of latency and quality of service. In addition, we analyze the IoT success factors of these LPWAN technologies, and we consider application scenarios and explain which technology is the best fit for each of these scenarios. <s> BIB009
The proprietary LPWA technology known as RPMA  was proposed by Ingenu (formerly On-Ramp). Unlike LoRa and SigFox, RPMA does not use sub-bands; it instead uses the global 2.4 GHz ISM band to realize a worldwide vision of the LPWA. RPMA relies on DSSS modulation, which does not impose a limit on the duty cycle or maximum frame duration in the global 2.4 GHz ISM band. For this reason, RPMA has the advantages of worldwide availability, wider spectrum utilization, and higher transmission power (and thus higher VOLUME 6, 2018 BIB002 , BIB003 , BIB004 , BIB009 , BIB005 , [39] , [40] , [45] , BIB006 , BIB007 , BIB001 -  . coverage) compared with LPWA technologies operating in fractured, regional sub-GHz ISM bands, such as LoRa and SigFox. RPMA features high data rates of up to 624 kbps on the UL and 156 kbps on the DL BIB002 , BIB006 , wider coverage and higher energy consumption than LoRa and SigFox due to the use of the 2.4 GHz ISM band BIB008 . Ingenu designed RPMA  for the physical layer to keep the packet size small and to enable unscheduled communication, which is not possible with DSSS  . Interference in the 2.4 GHz ISM band and limitation on power in some regions such as Europe are the main drawbacks of this technology  .