Search

The power consumption of wireless access networks will become an important issue in the coming years. In this study, the power consumption of base stations for mobile WiMAX (Worldwide Interoperability for Microwave Access), fixed WiMAX, UMTS (Universal Mobile Telecommunications System), HSPA (High-Speed Packet Access) and LTE (Long-Term Evolution) is modelled and related to the coverage. A new metric, the power consumption per covered area PCarea, is introduced, to compare the energy efficiency of the considered technologies for a basic reference configuration and a future extended configuration, which makes use of novel Multiple Input Multiple Output (MIMO) technology. The introduction of MIMO has a positive influence on the energy efficiency: for example, for a 4×4 MIMO system, PCarea decreases with 63% for mobile WiMAX and with 50% for HSPA and LTE, compared to a Single Input Single Ouptut (SISO) system. However, a higher MIMO array size (i.e. a higher number of transmitting and receiving antennas) does not always result in a higher energy efficiency gain. [ABSTRACT FROM AUTHOR]

Advances in wireless sensor technologies and MEMS have made it possible to automatically monitor the health status of dairy cows using Internet of things (IoT) and wireless body area networks. Since on-cow measuring devices are energy constrained, a proper characterisation of the off-body wireless channel between the on-cow sensor nodes and the back-end base station is required for an optimised deployment of these networks in barns. In this Letter, the long range (LoRa) off-body wireless channel has been characterised at 868 MHz, a typical IoT frequency. Both path loss and temporal fading were investigated using LoRa motes. Based on this characterisation, network planning and energy consumption optimisation of the on-body nodes could be performed, which enables the deployment of reliable dairy cow monitoring systems. [ABSTRACT FROM AUTHOR]