What is eMTC?

eMTC (enhanced machine-type communication) is a type of LTE-M network specified by 3GPP in the Release 13. eMTC is a low-power wide-area (LPWA) technology that supports IoT through lower device complexity and provides extended coverage. It is a sub-type of the LTE-M network, although the two terms are often used interchangeably. eMTC is also referred to as BL/CE where BL stands for bandwidth reduced, low complexity and CE stands for coverage enhancement. It is also referred to as LTE-M1 or CAT-M1.

The focus with eMTC devices is on providing a venue for machine-to-machine type communication, which requires a higher data rate and more overall throughput than the very low usage sensor devices that occupy the bottom end of the IoT. eMTC devices operate using existing LTE networks, however, unlike NB-IoT devices that operate using unused spectrum or guard bands, eMTC devices operate within the same LTE band used for cellular applications. This is advantageous to most carriers as they don’t need to spend resources to create new antennas. They simply got to upload new software as long as the devices operate within their LTE network. Since this technology co-exists with 2G, 3G, and 4G mobile networks it has the benefits of all the security and privacy features of mobile networks, such as support for user identity confidentiality, entity authentication, confidentiality, data integrity, and mobile equipment identification.

eMTC device category was introduced in 3GPP Release 13 specification as LTE Cat M1. LTE Cat M1 is sometimes used synonymously with eMTC. LTE Cat M1 is a complementary technology to NB-IoT, with faster upload and download speeds of 1 Mbps and lower latency of 10 to 15 ms. It requires a total bandwidth of 1.4 MHz and operates in both Half Duplex or Full duplex modes. One of the advantages that LTE Cat M1 has over NB-IoT is the ability to hand over from cell site to cell site, which makes it possible to use this technology in mobile applications. NB-IoT does not allow porting from cell site to cell site and therefore can only be used for fixed applications i.e those that are limited to the coverage area of a single cell site. In LTE, different categories have differing data speeds, frequency spectrum, power usage and signal range. The different LTE categories can be chosen depending on the trade-offs to be made, in other words, some aspects can be given up in order to gain advantages in another aspect. LTE Cat M1 trades in the high data rate delivered by LTE for better power efficiency and longer signal range and is therefore considered an "Internet of Things" (IoT) cellular technology. The lower data rates mean that the signal can travel further and it will take less power to do so.

In 3GPP Release 14, LTE Cat M2 was introduced which was a direct upgrade to the LTE Cat M1 eMTC standard. With LTE Cat M2, certain capabilities of eMTC were enhanced like data rate and bandwidth. LTE Cat M2 supported a peak uplink data rate of 7 Mbps and a peak downlink data rate of 4 Mbps compared to LTE Cat M1’s 1 Mbps. LTE Cat M2 also has a bandwidth of 5 MHz compared to LTE Cat M1’s 1.4 MHz. Thus, LTE Cat M2 offers the same advantages as Cat M1, but with faster speeds. In order to use Cat M2, Mobile Network Operators (MNOs) have to upgrade their Cat M1 infrastructure. However, IoT manufacturers won’t need to invest in new technologies as Cat M1 modems are still compatible with Cat M2 networks, and Cat M2 uses the same frequency bands. Other than the bump in bandwidth and data rates everything else is virtually the same, making LTE Cat M2 the clearly superior technology.

NB-IoT does not support automatic zone switching hence, terminals that use this standard are not portable. eMTC supports automatic zone switching and hence provides much better portability. Due to this reason, eMTC is preferred over NB-IoT for IoT applications that involve vehicles and mobile devices. NB-IoT does not support voice transmission, while eMTC does making it a better choice for IoT applications with voice functionality.

eMTC Device Specifications

Applications of eMTC

eMTC is best suited for IoT devices that are power-constrained and exchange limited volumes of traffic with the application. Here are a few examples of possible applications:

• Asset management
• Smart meters (temperature, air quality meter, etc.)
• Smart irrigation
• Vehicle/fleet tracking
• Insurance company
• Financial companies
• Car rental
• Car dealers
• Car mortgage
• Personal/Asset Trackers
• ATMs
• Sensor Nodes
• Utility Meters
• Monitoring Systems