e-of-sight or non-line- of-sight conditions occur. This is strongly dependent on the application as well as on the scenario under analysis. Telemetering applications of distributed wireless sensors in the case of lampposts for street lights, for example, will generally exhibit line-of-sight or partial line-of-sight connectivity, owing to the inherent layout of the lampposts in urban settings (i.e., series connection to one electric control box). If we are connecting electric smart meters, there will usually be non-line-of-sight conditions (especially in the case of blocks of apartment houses, where the meters will be located in an indoor facility within the building) until connection is established with the corresponding aggregator/gateway device. In this way, different network topologies can be supported, such as star configurations (e.g., LPWAN LoRa/LoRaWAN, with the possibility of simultaneous connection to more than one gateway), mesh configurations (e.g., ZigBee mesh, IEEE 802.11s, or Bluetooth Low Energy), or cooperative communication schemes (such as device-to-device connectivity Implementation of Context-Aware Environments with Massive IoT Systems within 5G). Multiple frequency bands can also be considered, although the vast majority of solutions take advantage of lower path losses and lower cost for sub 6 GHz frequency bands. Compact platforms: IoT applications inherently focus on large node densities, which require low-cost and small form factors. Additional considerations deal with operational conditions of the IoT nodes, which can be deployed in outdoor scenarios or industrial shop floors or logistical warehouses, among others. This leads to additional requirements in terms of ruggedization, with specific casings, connectors, or the use of resins in order to protect electronic circuits. More- over, compact platforms are mandatory in the case of biophysical monitoring applications, with additional ergonomic requirements in the case of wearables or biocompatibility in the case of implantable devices. In