## 2 Background--Related State of the Art
The authors of [12] performed an assessment of various IoT access network technologies, including Zigbee (Xbee), Bluetooth Low Energy (BLE)m and LoRa/LoraWAN via experimentation of specific devices in order to assess their coverage, throughput, and energy efficiency metrics and demonstrated the superiority of LoRa/LoRaWAN for moderate to high distances (above 100 m) in terms of throughput and energy performance, as compared to the other short-range access network technologies. Additionally, in [13], it was shown via experimentation that LoRaWAN could provide better energy efficiency and hence battery autonomy compared to GPRS in a smart irrigation system, at the expense of a moderate packet round trip time increase (that could be afforded by the specific target application). Furthermore, network planning for IoT access networks has been studied in many works in the literature. Various works [1; 14; 15; 16] have presented models for estimating the receiver sensitivity, minimum receiver SNR, and Time over the Air (TOA) in LoRaWAN links, without including device capacity estimations. Additionally, in [17], the authors investigated radio channel propagation models for the LoRaWAN 868 MHz band and for evaluating radio coverage for different environment types (indoor, urban, suburban, rural), considering also measurement campaigns. Similar work was conducted for NB-IoT by the authors of [18,19]. These findings motivated the current work in order to perform the coverage planning assessment and cell range calculations for different spreading factors and to further exploit them for device capacity dimensioning. In [20,21], the authors present comprehensive studies regarding the PHY and MAC procedures in NB-IoT, without providing a device capacity assessment. Additionally, in [2], the authors analyze the coverage and capacity of fixed LoRaWAN networks and extend it to mobile use cases in [22]. The present work is inspired by these findings and adopts in the developed models some of the concepts presented in these works, in order to develop an integrated methodology for assessing the coverage and capacity of additional standards such as NB-IoT. In [23,24], key NB-IoT system parameters are presented, and a preliminary analysis of the system throughput is provided, giving valuable insights regarding methodology for coverage and capacity planning in the present work, which extends these ideas to derive maximum numbers of devices depending on cell coverage ranges and on the application payload and packet rate parameters. Furthermore, [25] presents a comprehensive review of radio resource management calculations for NB-IoT, with useful information on the coverage estimation and on the actual packet repetition patterns that are considered in different cell ranges that also inspired the present work. Our work complements the related state of the art by considering key characteristics of LoRaWAN and 3 GPP NB-IoT, in order to formulate an integrated framework for assessing the radio coverage and device capacity for each access network technology. Such composite modeling results are important for considering the deployment characteristics of respective IoT access networks in unlicensed or licensed frequency bands and for determining actual throughput levels, the numbers of supported devices, and the respective radio coverage ranges that can be achieved.