Choosing Between LTE-M, NB-IoT and 4G for Remote Equipment

For years, a lot of remote monitoring equipment ran on 2G or 3G. UK operators have been switching off 3G, and 2G is being phased out too, with the government and operators working towards ending 2G and 3G services by 2033. Any device that relies on them will eventually lose its connection.

The replacements are 4G-based technologies designed for connected devices. LTE-M and NB-IoT were built specifically for low-power equipment, while LTE Cat 1 and Cat 1 bis offer a simpler, lower-cost version of standard 4G. When buying or replacing devices now, it makes sense to choose ones that support these networks.

LTE Cat 1 and Cat 1 bis are the entry level of standard 4G. They use the same network as phones, so coverage generally follows normal 4G coverage. Cat 1 bis is a simplified version with a single antenna, which makes devices smaller and cheaper while keeping similar performance. They suit assets that send regular or larger amounts of data, or move between sites.

LTE-M (also called Cat M1) is a low-power version of 4G. It carries less data than Cat 1 but supports movement between cells, reasonable response times and even voice in some cases. It also tends to reach further into buildings and weak-signal areas than standard 4G.

NB-IoT (Narrowband IoT) uses a very narrow slice of spectrum to send small amounts of data with very low power. It is best for fixed sensors that send short readings, such as a level or temperature every so often. It is not designed for moving assets or anything needing quick responses.

Figures below are typical and approximate. Real performance depends on the network, signal strength and how the device is configured.

For most monitoring, raw speed matters less than it seems. A status message from a generator or tower is small, so all three can carry it. The bigger differences are power use, how well the signal reaches the site, and whether the asset moves.

Coverage is the factor most likely to decide the choice, and it varies by site, by operator and by technology. Not every operator offers LTE-M and NB-IoT everywhere, and a site with strong phone signal on one network may be weak on another.

Check coverage for the specific location with the network provider or your connectivity supplier before deploying, and if possible test on site with the actual device. Devices that support several technologies and can fall back from one to another give you more room when a site turns out to be harder than expected. Antenna position also matters: an antenna mounted high on a tower or mast will usually perform better than one inside a steel enclosure.

Remember that sites change. Scaffolding, cladding, stored materials and new structures can all weaken signal as a project progresses, so an asset that connected well on day one may struggle later. Alerts for devices that stop reporting help you spot this before it becomes a gap in your monitoring.

If equipment sits in a compound, cabin or building that already has a reliable internet connection, a wired Ethernet link avoids signal problems and mobile data costs altogether. It suits fixed gateways, site offices, battery storage containers and permanent installations.

Many sites use both: Ethernet where a network is available, and cellular for assets spread around the site or on the move. Some gateways support both, so cellular can act as a fallback if the wired connection fails.

Ethernet also suits equipment that produces more data, such as a site battery system with many readings per minute, or where the site owner prefers monitoring traffic to run through their own network. Keep in mind that a copper Ethernet cable run is limited to around 100 metres per segment without a switch or other equipment in between.

TrackSyte's gateways cover these options. Neo uses LTE Cat 1 bis with Wi-Fi and Bluetooth, Hub is an Ethernet-connected site gateway, and Neo 2 supports LTE, LTE-M and NB-IoT as well as Ethernet, so the connection can be matched to the site rather than the other way round.