Diseño e implementación de una red de radioenlaces integrada a redes comunitarias mediante la metodología PPDIOO para el acceso a internet a estudiantes rurales y la aplicación de agricultura inteligente en La Calera

Abstract

The Buenos Aires Rural School, in the municipality of La Calera (Cundinamarca, Colombia), had no Internet service: field inspection verified that no commercial provider offers coverage in the village and that no usable mobile signal is available for data. Its 40 students and 2 teachers had no means of connection whatsoever. This work documents the design, construction and validation of the radio link network that carried the service from the town centre to the school, separated by a mountain that blocks line of sight between the two points. The solution was resolved as two chained hops of 2.91 km and 8.10 km in the 5.7 GHz license-exempt band, in compliance with Resolution 105 of 2020 of the Colombian National Spectrum Agency, joined by a repeater node installed at 3,151 m above sea level, where no power grid reaches. That node runs on a standalone photovoltaic system sized for 80 W against the 23.5 W drawn by the equipment, a reserve intended to extend the network towards other villages in the municipality. Development followed the PPDIOO methodology, with a link budget computed analytically, verified through simulation over the real terrain profile, and subsequently contrasted with on-site measurements. The school went from having no connection to receiving a steady 22.3 Mbps downstream and 6.9 Mbps upstream, with peaks of 40.04 Mbps, against the 15 Mbps set as the minimum in the needs assessment; thirty days of operation yielded 99.99 % availability. The network operates under a community scheme formalised in Memorandum of Understanding No. 475-2025 between Universidad Distrital Francisco José de Caldas and the Municipality of La Calera, at no cost to the school and on license-exempt spectrum. The same link provides transport for the gateway of the sensor network that a parallel project deployed across the village's potato fields, a channel without which frost alerts would never reach their server. The results were externally reviewed through an article approved for publication in an indexed journal.