LTE wants to be all things to all verticals when it comes to M2M. LTE’s high data rates are obviously good for consumer broadband services such as video. Those same data rates also make LTE an attractive technology to embed in cars to provide onboard communications and entertainment.
However, not all M2M connections need high data speeds: for some, modules with long battery life and low price points are more important. What makes LTE attractive for M2M is that it can address this wide array of use cases. 2G and 3G can’t make similar claims.
Starting with 3GPP Release 12, machine-type communications (MTC) enhancements have become a bigger focus for LTE. So while 3GPP continues to work with standards around LTE-Advanced and LTE-Advanced Pro to push LTE speeds towards 1 Gbps using multiple technologies such as 4x4 MIMO and multi-carrier aggregation, it is also working to take LTE in the opposite direction so that LTE M2M can replace GSM M2M and other M2M connections that prize low-cost modules and long battery life over high network speeds.
Network factors for LTE M2M success
There are a number of network factors that will determine the success of LTE M2M. For a start, broad coverage is crucial. Coverage of course is always important when it comes to wireless services, and M2M is no exception: if the operator can’t connect the device the enterprise will select a different communication technology.
With M2M, mobile operators face greater challenges than normal. M2M requires the network to connect stationary devices sometimes located in hard-to-reach areas such as basements of high-rise buildings. 3GPP Rel. 13 will bring enhancements here to help facilitate better LTE machine-type communications. The network will be able to handle lower-power communications to extend its reach. Signal changes such as repeating the communications transmission will help extend coverage as well.
Not to be overlooked is the fact that to replace GSM for M2M, LTE will need a network footprint equal to that of GSM. Coverage should give mobile operators an advantage over newer proprietary LPWA M2M solutions: proprietary LPWAs have to completely build out their network footprints, while mobile operators can use their existing LTE footprint for M2M.
A second network factor is that exponentially more connections must be supported. Getting from hundreds of millions of connections to tens of billions of connections will put a strain on mobile networks. Optimizing the LTE network to handle so many more connections will require changes within the packet core networks, such as dedicating certain EPC elements for IoT, differentiating latency levels based on class of service, and opening network elements up to third-party IoT application providers. Neither 2G nor 3G offer similar capability, which helps the case for LTE versus older mobile technologies when it comes to the connectivity layer of cellular IoT.
However, LTE itself wasn’t originally designed for cellular IoT either, and these changes are an addition to the original broadband standard. 5G in comparison is being designed from the outset to support cellular IoT.