Sub-GHz LPWAN Network Coexistence, Management and Virtualization: An Overview and Open Research Challenges

Eli De Poorter, Jeroen Hoebeke, Matthias Strobbe, Ingrid Moerman, Steven Latré, Maarten Weyn, Bart Lannoo, Jeroen Famaey
2017 Wireless personal communications  
The IoT domain is characterized by many applications that require lowbandwidth communications over a long range, at a low cost and at low power. LPWANs (Low Power Wide Area Networks) fulfill these requirements by using sub-GHz radio frequencies (typically 433 or 868 MHz) with typical transmission ranges in the order of 1 up to 50 kilometers. As a result, a single base station can cover large areas and can support high numbers of connected devices (> 1000 per base station). Notorious initiatives
more » ... in this domain are LoRa, Sigfox and the upcoming IEEE 802.11ah (or "HaLow") standard. Although these new technologies have the potential to significantly impact many IoT deployments, the current market is very fragmented and many challenges exists related to deployment, scalability, management and coexistence aspects, making adoption of these technologies difficult for many companies. To remedy this, this paper proposes a conceptual framework to improve the performance of LPWAN networks through in-network optimization, cross-technology coexistence and cooperation and virtualization of management functions. In addition, the paper gives an overview of state of the art solutions and identifies open challenges for each of these aspects. gap allowing devices to be connected without requiring significant infrastructure investments. LPWAN technologies have several defining characteristics. (i) They have very low power consumption, resulting in a battery life of up to 15 years for some applications. (ii) They support only short information exchanges, often 100 bytes or less. (iii) They have very low device unit costs; the connectivity module will eventually cost less than a few dollar. And (iv) they are designed to have good coverage indoors and outdoors. Due to the use of sub-GHz radio frequencies (typically 433 or 868 MHz in Europe), a single LPWAN base station has a large coverage area, with a range from 1 up to 50 km. This way, a single base station can support high numbers of connected devices (> 1000 per base station). Although the size of and frequency of information exchanges is limited, this disadvantage is off-set by the fact that a single sub-GHz base station can cover an area of multiple square kilometers, allowing cost-effective installations of large IoT deployments. Currently, several sub-GHz technologies are being promoted simultaneously, all of which use the same (limited) wireless spectrum. Notorious initiatives in this domain are LoRa, SigFox, IEEE802.15.4g and the upcoming IEEE 802.11ah (or "HaloW") standard. However, as several LPWAN technologies are entering the market simultaneously, several global trends start to emerge. Currently, the promising LoRaWAN technology is still in its early phase of adoption but the technology will definitely mature during the coming years, especially when adding improvements regarding scalability, QoS, cross-layer optimizations, improved MAC features, cross-network coordination, etc.
doi:10.1007/s11277-017-4419-5 fatcat:pg7k22eg2nb6nbvgea6e27lao4