Extremely energy efficient
Energy efficient network
A special feature of our IoT network is the extremely low amount of energy required to send sensor data from your device to your own cold environment. This makes you independent of a fixed power connection and allows your device to run on a battery for years. A device can run on two AA batteries for up to 5 to 10 years.
NB-IoT is designed for long distance data communication with the lowest possible energy consumption. Two of the power consumption optimisations within NB-IoT are Power Saving Mode (PSM) and Extended Discontinuous Reception (eDRX). In addition, the Periodic Tracking Area Update (TAU) has been modified from 4G to reduce the number of times the TAU has to take place and thus reduce energy consumption.
Using the PSM, the radio module in the device can be put to sleep for 310 hours. During this sleep time the energy consumption is a few microamperes. The device will not communicate with the network during this time. If the device does want to send data, for example because a sensor has taken a measurement that exceeds a certain value, the radio module can automatically exit sleep mode and directly send the desired data over the network without first having to establish a connection with authentication and authorization. The security is maintained in the network during 'sleep'. By regulating this sleep time as optimally as possible, energy consumption is reduced to a minimum.
For some use cases, where the device mainly receives data from the network and sends almost no data, the time the device listens to the network can be adjusted. This 'listening appointment' between the device and the network can be extended with eDRX every 10 seconds to once every three hours. Examples of these use cases are systems such as an irrigation system, which can then be operated remotely.
Long Periodic TAU
A device should give a Tracking Area Update to the network once in a while so that the network knows that this device is still 'alive' and with which cell it communicated the last time. The security keys are also quickly updated.
For our IoT network this TAU now takes place once every 310 hours and will soon be adjustable so you can make it happen less frequently. The TAU is connected to the PSM. After the PSM expires a TAU will automatically take place to let the network know that the device still has (and needs to keep) a connection to the network. If this doesn't happen, another network attach will have to take place. This takes longer and consumes more time (and energy).