When the new generation of Cat-M1 (LTE-M) and NB-IoT networks began rolling out, there was considerable speculation as to which markets would push forward each technology. The two largest U.S. carriers decided to prioritize Cat-M1 networks, while Chinese operators prioritized NB-IoT with its simpler and less costly technology.
At the time, Cat-M1 and NB-IoT were considered to be competing technologies. However, most mobile network operators have since come to the realization that these will compliment, rather than compete, with each other. Thus, we are witnessing a global approach to utilize both technologies.
Based on observations at this year’s MWC Shanghai, the adoption of NB-IoT in China has been slower than expected. Despite initial projections that NB-IoT deployments in China alone would exceed 100 million units by the end of 2018, according to the most optimistic estimates there are currently no more than 10 million NB-IoT connections globally.
This is due partly to the unsuitability of NarrowBand IoT for wearable devices (NB-IoT does not support voice and mobile applications). The lack of VoLTE (Voice over LTE) is a significant limiting factor, particularly for those carriers that do not support Cat-1 VoLTE for IoT at FDD bands. NB-IoT’s low data rates also make FOTA (Firmware over-the-air) upgrades unfeasible, creating another obstacle for the mass rollout of NB-IoT-based devices. Meanwhile, all carriers operating both NB-IoT and 2G are experiencing handover issues when transitioning between the two technologies.
The sudden interest in Cat-M1 derives primarily from its ability to facilitate voice, whether via VoLTE or OTT. This, in addition to its support for connected mobility and higher throughput, makes Cat-M1 essential for a range of emerging applications including wearables, trackers and emergency response communication devices.
Consequently, all three major Chinese carriers are now considering deploying Cat-M1 networks. Intensive trials are underway and the first commercial Cat-M1 networks in China are expected to rollout by the end of the year.
It was always anticipated that most markets would eventually roll out both Cat-M1 and NB-IoT networks. Nevertheless, China’s change of course, following the general trend of major global cellular operators, presents a significant opportunity for dual-mode chipsets and a much wider range of IoT devices.