If you have a smartphone, you probably use LTE often updated iPhones and Android phones these days are able to use the LTE protocol for blazing fast Internet access. Sometimes called 4G, this wireless standard has superseded the older, slower standards of 2G and 3G for mobile phones in much of the world, with over 75% penetration across the US, Europe, and especially in Asia. But when it comes to the Internet of Things and machine-to-machine communications, LTE is just beginning to make an impact.
Long Term Evolution (LTE) was designed to use a new protocol called Orthogonal Frequency Domain Multiple Access (OFDMA). Its generally been called a Fourth Generation (4G) technology, since its very different from the previous 3G.
LTE Is More Spectrally Efficient
One thing that sets it apart is that LTE is very flexible in terms of the channel widths that can be used, and thus the available spectrum bands can be partitioned into smaller blocks more easily. And it also allows existing spectrum to be partitioned into multiple blockswhich can allow a carrier to deploy 4G without having to entirely remove older technologies.
The flexibility comes at a price. There are more than 30 bands available for LTE use and countries have not auctioned or made available the full set of possible bands. In fact, some bands may be impossible to use in certain countries because they are dedicated to other uses.
That means handsets or IoT /M2M devices using LTE everywhere must support a number of different bands, and this can add costs for additional filters and power-amplifiers inside the radios to support each band. But, as with most types of hardware, the prices are coming down as more and more LTE units are deployed.
Categories of LTE
LTE also uses the concept of categories (CAT) to define a set of performance metrics that are dependent on other parameters (such as the number of spatial layers, antennas, protocols). Originally defined as CAT 1 through CAT 8, these provided a different range of performance from 10 Mbits/sec download speeds in CAT 1 through 1200 Mbits/sec downloads in CAT 8.
For IoT/M2M applications, CAT 1 radios would be sufficient performance, but were not originally developed since the LTE chipsets with CAT 1 support were not deemed adequate for smartphone users.
Recently, the standards bodies also defined CAT 0 radios for LTE that have reduced performance and network requirements, and these are in the process of final definition and ratification. These are expected to be supported in LTE chipsets and within the network (since changes are required in the network deployments too) within the next few years. CAT 0 radios that do not support the higher performance requirements of LTE categories should be less expensive, since the chipsets should be substantially lower in cost too.
Cellular FallBack or LTE-Only?
The cellular radios essentially fall back from newer generations to older generations when the newer generation service is not available at a particular geographical location. The control of when to fall back (including which technology to fall back to) are incorporated in the SIM.
These fallback mechanisms increase the complexity and cost of the chipsets within the IoT/M2M modules. In time, when LTE is commonly available everywhere that cellular services are deployed, it makes sense to use LTE-Only radios, which should be less expensive.
Businesses who want to migrate from 2G to 3G services to 4G may find it worthwhile to wait for this cost reduction in LTE-Only modules to make the transition. The transition date will be dependent on your product longevity requirements.
Need more information about LTE? Wondering if your IoT deployment is ready to upgrade? Contact us by email or phone 1-888-GO-AERIS (1-888-462-3747).