# Performance Evaluation of LoRa Considering Scenario Conditions
## 6 Conclusions  
In this work, a comprehensive performance evaluation of LoRaWAN in several realistic scenarios has been presented. Different configurations of LoRaWAN PHY layer were explored in order to evaluate the most proper one depending on the propagation conditions. Three typical environments, namely, urban, suburban, and rural have been studied with the aim of considering their adversity to wireless transmissions and, consequently, their impact on the system performance. First, the estimated signal level in these scenarios have been evaluated by means of a precise planning tool, which employs topographic maps and the Okumura-Hata model. Thereafter, the attained outcomes from the theoretical study have been validated by an extensive sampling campaign. In the most adverse scenarios, i.e., urban and suburban, coverage ranges around 6 km were attained; in turn, in the open scenario (rural), a long transmission distance of over 18 km with the lowest data-rate was achieved. From the discussed results, it can be concluded that there is a clear trade-off between link robustness and data-rate (and consequently packet time-on-air); hence, depending on the propagation conditions and the distance between the base-station and the end-node, the LoRaWAN configuration parameters should be accordingly tuned. Particularly, in the urban scenario, for links shorter than 3 km, same levels of PDR were attained for the different DRs under evaluation. Therefore, with the aim of reducing the time-on-air for each packet, it is more convenient to employ high DRs. When the distance between both communication end-points is enlarged, lower DRs allow increasing the link robustness at the expense of dramatically decreasing the transmission rate. Finally, after evaluating the performance of the system under dynamic conditions, the interest was focused on examining the same scenarios but in a static situation to quantify the effect of mobility on performance. For that reason, a nomadic test was also conducted in order compare both scenarios. The results of this experiment confirmed that LoRaWAN presents a notable vulnerability related to the Doppler effect when using high transmission data-rates, but this effect is much less notable in the case of using low DRs. In the light of these results, it can be concluded that LoRaWAN presents a high level of adaptability to be employed in several IoT applications, such as smart cities, fleet/goods tracking, etc. Therefore, by applying the most proper configuration, the transmission system is able to establish long links with high robustness and low power consumption even under mobility conditions. For that reason, as future work, we plan to provide more intelligence to the system, in order to make it capable of auto-adapting the LoRaWAN PHY layer settings to current environmental conditions.  
This work has been sponsored by the Spanish Ministry of Economy and Competitiveness through the EDISON (contract TIN2014-52099-R), FERSEIDES (contract TIN2017-86885-R), and CHISTERA (contract PCIN-2016-010) projects, and the AEI/FEDER UE project grant TEC2016-76465-C2-1-R (AIM).  
[PERSON] conceived and designed the experiments; [PERSON] and [PERSON] performed the experiments; and [PERSON] and [PERSON] analyzed the data. All the authors contributed to write the paper.  
The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.