There are over a dozen LPWA technologies contending to provide connectivity for some of the billions of connected devices as projected by market analysts. How they all compare with each other is a hot topic in the race to markets. We recently published detailed analysis benchmarking these technologies in terms of capacity, range, throughput, power consumption and other characteristics*. In the process we developed a graphic for two parameters – range and throughput. Both are important parameters, but in the context of IoT, they are not the only parameters that need to be considered. Nevertheless, it is worth outlining some important aspects of this graphic.When it comes to range, technologies in the licensed spectrum bands will on average perform better than those in unlicensed spectrum for the simple fact that interference in unlicensed spectrum cannot be controlled. This leads to higher margins that need to be added for public networks to ensure a specific coverage grade is met.
Unlicensed spectrum has lower radiated power limits than licensed spectrum. This works in favor of licensed-spectrum technologies to achieve longer range. Moreover, because regulatory requirements vary from country to country leading to different performance. Thus, a LoRa or SigFox network in France would have different performance than one in the US. The same is not true for licensed band technologies which are constrained by other factors.
Implementation impacts performance. Licensed-band technologies, leveraging the cellular networks, are designed to take advantage of installed base stations. Thus, they support multiple antennas for diversity and other features that extend coverage. Unlicensed-band LPWA technologies implement their own features to make connectivity more robust, which would have to be accounted for. These features impact performance and cost.
Throughput performance is related to range and the number of devices served by the gateway/base station. Average throughput provide an indication on what is actually possible in practice as opposed to peak throughput which is unattainable most of the time. Throughput will decrease as more devices contend for access. This is a major differentiator among technologies.
There are multitude of IoT applications. Each application has unique requirements. No one technology can serve all the applications efficiently. A few technologies will be required to meet the broad spectrum of applications. Technologies have to be evaluated in the context of applications. This is a critical point. The success of LPWA technologies will be defined by the ability of each player to develop its markets. The challenge is not one of technology performance, but it is in providing a solution to a problem that customers are willing to pay for. Where there is strong overlap in technology, history has shown that it not always the best technology that wins the race.
* Contact me for information on our analysis on LPWA technology performance.