I am continuing with the third post in my series LoRaWAN vs 5G. As I am invited to speak about 5G at a LoRaWAN event (ThingsConference 22nd of September 2022), I found it appropriate to dig into the aspects of LoRaWAN vs the different, current 5G standards for LPWAN. In the last post, we compared distances and ranges; in this post, we are looking at coverage for the different standards. I found a comparison from LoRa Alliance that I mentioned in my last post, it states that:
LoRaWAN: Deep indoor coverage (through concrete, metal), stronger performance in rural, hilly areas
5G LPWAN: Deep indoor coverage is challenging for the operator’s macro network and costly for additional indoor coverage
Again, LoRa Alliance is, in my opinion, comparing apples and pears. I will explain why.
The indoor coverage parameters
LoRaWAN and 5G capability of penetrating walls are depending a few things. Given that the material in the walls is the same in both cases, a handful of factors impact the result.
- Distance from the base station
- Signal integrity from other radio systems
- Reflections, diffractions and other radio phenomena
- Transmitters output power
- Receiver sensitivity
- The actual frequency used
- The modulation of the radiosignal
- The antennas used
Let us, in this case, disregard 1-3 as they will be the same if we compare these technologies in the same situation. 7-8 are, according to real life tests of Aalborg University very similar, so let us focus on 4-6. The frequency used in this case is approximately the same. 5G uses the 700-MHz band, and LoRaWAN uses the mid-800-band. These are relatively similar; there is a small upside for 700 MHz in terms of signal propagation. In other words, 5G will reach slightly longer and penetrate walls better, but let us not focus on that right now. Let us look at the transmitter output power and receiver sensitivity. In the last post, I described MCL; you can look at that part if you are jumping in now. As you can see, 5G has better MCL than LoRaWAN.
Looking at facts
There is a report from Aalborg University – Coverage comparison of GPRS, NB-IoT, LoRa, and SigFox in a 7800 km2 area The University did a thorough simulation of the coverage of GPRS, Narrowband-IoT, LoRa, and SigFox compared in a realistic scenario, covering 7800 km2. The target was to evaluate which of the four technologies provides the best coverage for Internet of Things devices, which may be located deep indoors. The results show that NB-IoT, having the best MCL, offers the best coverage. In the tests, NB-IoT had an outage below 1% for locations experiencing 20 dB indoor penetration and outdoor path loss. LoRaWAN cannot provide coverage for 2% of those locations. For the challenging deep indoor case, where 30 dB additional penetration loss is added, NB-IoT has an 8% outage, and LoRaWAN cannot cover 20% of the locations.
Transmitted power in LoRa is affected by regional limitations (14 dBm ). NB-IoT and CAT-M1 support transmitted signal of 23 dBm. The comparison between these two groups from coverage perspective is kind of unfair, but reflects reality. LoRa overcome these challenges with chirp spread spectrum as modulation which performs on large distances and is robust against interference and noise. Of course, if you are also considering spectral efficiency, NB-IoT is the better choice. NB-IoT is more suitable for future networks with massive numbers of devices if you consider the radio spectrum. (One called “Power Consumption Analysis of NB-IoT and eMTC in Challenging Smart City Environments” by Pascal Jörke, Robert Falkenberg and Christian Wietfeld)
What is the conclusion?
I think LoRa Alliance intended to mention that LoRaWAN is a suitable technology for easy indoor deployments. It is perfect for constrained areas. The indoor coverage can be built to match a specific need. However, 5G, as long as there is coverage, can easily be deployed in similar situations, and private 5G networks have become more and more available. But if we look at the shear statement from LoRa Alliance:
LoRaWAN: Deep indoor coverage (through concrete, metal), stronger performance in rural, hilly areas
LTE: Deep indoor coverage is challenging for the operator’s macro network and costly for additional indoor coverage
Then I think this statement would make sense:
LoRaWAN: Deep indoor coverage, good performance in rural, hilly areas. Easy to extend coverage by adding your own base station.
5G LPWAN: Excellent indoor coverage, good performance in rural, hilly areas. Possibility to extend coverage by adding a private 5G base station.