# LaRoAwan and Urban Waste Management--A Trial
## 6 Conclusions  
The objective of this study was to verify the applicability of LoRa technology to support the transmission of the filling level of waste containers throughout the city of Lisbon. A set of tests were carried out, under different conditions and scenarios, allowing the conclusions presented here to be supported by empirical knowledge, which complements the existing technical and scientific information. In the case of coverage over long distances, the failure to receive messages confirmed the criticality of rigorous network planning, in order to ensure adequate radio coverage of the city. It is therefore essential to adopt link budget margins, compatible with existing conditions, during network planning. It also proved the importance of the characteristics of the antenna used in the sensor and its impact on the performance of radio communication. Regarding the coverage of underground waste containers, a situation that was expected to be more unfavorable than the other different verticals, radio coverage that allowed for communication was possible, even in a no line of sight situation. Thus, the tolerance to high levels of attenuation of LoRa was confirmed. It was therefore interesting to verify the performance of this technology, in comparison with the solution currently installed (GSM/GPRS), under the same installation scenario, even in the most adverse conditions. Based on the results presented, it is possible to conclude that LoRa allows to fully support the transmission of data to monitor the filling level of waste containers. This possibility applies at the following levels:  
* Capacity, where it was possible to confirm that the capacity offered by technology for data transmission is sufficient to satisfy the need for the application in question, even in unfavorable conditions, which imply a lower transmission rate;
* Radio coverage, showing the feasibility of using LoRa technology to support communication with sensors installed inside the different types of containers. This possibility was validated in the most unfavorable situation, namely in underground containers, with additional attenuations, associated with the penetration of the radio signal. Ultimately, this research led to the deployment of a municipality wide local area network to support the Waste Management Department and the Public Park Management Department of the Lisbon Municipality as well as preparing the grounds for other initiatives promoted by Lisbon City Council. The current ecosystem surrounding smart cities sets pace to the rise of technologies such as LoRa, that proves to be flexible and fitted to the most demanding smart city verticals such as urban smart waste management. Managing an increasing number of waste types with a common fleet of waste collection trucks proves to be difficult. With this restriction in mind, the continuous monitoring of the waste level of containers, helps to ensure a better management of the waste collection truck fleet, by only collecting waste from containers that are full, effectively improving the overall fleet efficiency. An improved efficiency leads to the increase of the number of recyclable types of waste containers, which will indirectly lead to less landfill usage of unrecyclable waste. The trend on the landfill usage is that it is decreasing for the past years at European municipalities [53]. The results presented in this paper allow a municipality to support the decision process on the selection of an LPWAN for the second most addressed smart city vertical. This is probably one of the most demanding considering LPWAN connectivity, given the high number of devices and their installation characteristics, particularly at underground waste containers. Conceptualization, N.C. ([PERSON]); Funding acquisition, J.T. ; Investigation, N.C. ([PERSON]) and N.C. ([PERSON]); Methodology, N.C. ([PERSON]); Project administration, J.T. ; Resources, J.T. ; Validation, N.C. ([PERSON]); Writing--original draft, N.C. ([PERSON]); Writing--review and editing, N.C. ([PERSON]).