Increase M2M Device Efficiency with LTE-M Wireless

The Third Generation Partnership (3GPP) telecommunications standard-building organisation has recently introduced the new LTE-M, or LTE for Machine-Type Communications, standard.

LTE-M is intended to allow devices that operate on LTE (Long-Term Evolution) cellular networks to be less expensive, both in terms of hardware deployment and bandwidth costs, more power efficient - and generally better suited to the requirements of Internet-of-Things and M2M applications.

With IoT and M2M communications becoming more widespread, there has been a growing need for a version of LTE that meets IoT-oriented requirements of low power consumption and low cost at relatively low data rates, and this is exactly what LTE-M aims to deliver - low power consumption (up to five years for a device running on AA batteries), easy deployment, interoperability, low overall cost, and reliable wide-area coverage.

A key advantage that LTE-M has over alternative technologies for low-power wide-area IoT networks, such as SigFox or LoRA - is that it takes advantage of the existing LTE network infrastructure with no need to deploy new hardware.

Since LTE-M is able to share spectrum with standard LTE devices, this makes it a more attractive option for most mobile network operators compared to alternative LPWA technologies. Telcos only need to upgrade the software on their towers to enable support for LTE-M, without any need for hardware upgrades, which helps to keep transition costs low.

And as LTE-M is just a physical-layer change for operators, all upper-layer cellular features such as global roaming, billing, subscription management and support services can transition seamlessly.

LTE-M is also known as "Category 0" LTE, the lowest of the LTE device bandwidth classes, with a peak speed of 1Mbps. Category 0 is specifically aimed at the requirements of typical IoT and telemetry applications which require low cost and low power consumption, but not large amounts of bandwidth.

As well as reductions in power consumption and hardware cost in these more bandwidth-constrained devices, coverage range and reliability is improved, which is another desirable factor in the IoT market where devices may be used in remote areas on the edge of a network cell.  All these improvements, in hardware cost, network coverage and power efficiency, are important to ensure that IoT and M2M applications can be cost-effectively deployed on LTE mobile networks.

These changes are becoming more important as telecommunications network operators look to shut down obsolete 2G GSM - and even 3G, in some cases - network infrastructure. In Australia for example, Telstra has announced plans to have its 2G GSM infrastructure shut down by the end of 2016 - and although this is not a concern for typical consumer voice and data services it is potentially a real problem for some embedded IoT and machine-to-machine infrastructure where 2G modems are used on Telstra's network.

A practical transition for these systems needs to be available soon, and it needs to be cost-effective and as simple as possible.

Although the standards that define Category 0 LTE-M devices are still a year or two away from widespread use, Category 1 LTE devices are deployable now, and these are viable for many M2M applications.

For example, Sequans has introduced a Category 1 LTE chipset solution named Calliope that is available now and is specifically aimed at the needs of low-cost M2M applications. LTE Category 1, at speeds of up to 10 Mbps, has been part of the 3GPP's LTE specifications since the earliest days, which means that LTE network operators can support Category 1 devices without any need for network upgrades.

Category 1, and later Category 0, devices provide significant cost and power reductions compared to higher-bandwidth Category 4 or higher LTE devices, but they maintain seamless coexistence with regular LTE networks.

Category 1 LTE chipset solutions like Calliope offer engineers a basis for transitioning their cellular IoT/M2M designs which is available today and is sufficiently low-cost to remain competitive with existing 2G and 3G solutions while still providing all the performance, cost and longevity advantages of LTE connectivity.

Allowing devices that don't require high throughput, like most M2M/IoT devices, to only access the limited class of bandwidth that they need allows cellular networks to be managed more efficiently, which is another advantage of using these low-bandwidth LTE device classes for IoT applications.

LTE-M includes mechanisms that give service providers the option of designating LTE-M IoT traffic as lower-priority than voice or video traffic from higher-revenue subscribers. This capability benefits both high-bandwidth Internet users and low-bandwidth IoT users as well as the telcos themselves.

Network operators reduce costs by using a single network for latency-tolerant IoT traffic and higher-bandwidth real-time services, while also avoiding the need to carve out spectrum for IoT markets that may take some time to grow in revenue. High-bandwidth users get more reliable services and IoT users get lower-cost subscription options that cost-effectively provide the amount of data and bandwidth they need.

Overall the upcoming LTE-M specification offers a win-win for both network operators and end users’ hardware and Internet-of-Things devices. And here at the LX Group we have end-to-end experience and demonstrated results in the entire process of IoT product development, and we’re ready to help bring your existing or new product ideas to life. Getting started is easy – click here to contact us, telephone 1800 810 124, or just keep in the loop by connecting here.

LX is an award-winning electronics design company based in Sydney, Australia. LX services include full turnkey design, electronics, hardware, software and firmware design. LX specialises in IoT embedded systems and wireless technologies design.

Published by LX Pty Ltd for itself and the LX Group of companies, including LX Design House, LX Solutions and LX Consulting, LX Innovations.