LoRa Or NB-Iot, Which Is The Right One For Your Application?

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Introduction

We’ve had customers and partners asked us, which is a better LPWAN connectivity for their projects – LoRa or NB-IoT?. Truthfully, it’s not a straightforward answer.  LoRa and Nb-IoT are complementary technologies with the most promise and momentum in the LPWAN race. To help you decide, we’re sharing our thoughts on what you should consider when deciding between LoRa and NB-IoT.

LPWAN Technologies

Low power wide area network (LPWAN) is a connectivity technology developed for IoT devices. It’s designed for low bytes of data from sensors, optimized for range and low power consumption. It’s perfect for sensor applications.

Here are some considerations when selecting between LoRa and NB-IoT:

Availability

The first question you have to ask yourself is, do I have coverage for the connectivity? There is limited commercial implementation of NB-IoT in Malaysia and sometimes the decision is made for you. A private LoRa network might be the only choice if none of the telcos have rolled out NB-IoT in the area. We have not seen any of them (Malaysia) publish their map of NB-IoT coverage. Drop us a note if you see one.

Total Cost of Ownership

Currently NB-IoT modules in devices costs slightly more than LoRa devices. This is largely because LoRa has been around longer and has had wider adoption. However, we see the adoption of NB-IoT is rapidly increasing globally, which may make the device cost difference negligible over the life of the product.

LoRa is on an unlicensed band. In Malaysia, we’re on the AS923 frequency plan which we share with Japan, Singapore, and Indonesia.  Anyone can purchase a LoRa gateway and the market has a wide choice of gateway for every budget and performance. You have a one-time cost and a small monthly cost for your backhaul connectivity. (i.e. a one data sim card for one gateway)

Maxis, Celcom and TM have all turned on NB-IoT selectively. We’re lucky to be in Cyberjaya as we’re able to get NB-IoT connection from all three and have tested our device with all three telcos. None of the telcos have published their prices but informal indications put it around RM3/month for most applications.

Market Ready Solutions

Although LoRa has been around longer than NB-IoT, many of the devices that are available in the market are for the European market (EU863 frequency plan) or the American market (US915). Those devices won’t work for the Malaysian market.

NB-IoT modules support multi-band and devices developed anywhere (as long as meeting GSMA standard) would work here.

Coverage

The link budget for LoRa and NB-IoT is quite similar. LoRa has link budget of between -155db to -170db while NB-IoT has -164db. If you need indoor and outdoor coverage, NB-IoT might be a better choice as it has better structure penetration.  You will have to work the telcos to get their coverage map. (quick plug: we’re working on a device to measure RSSI, get in touch if you’re interested)

Before deploying LoRa, make sure you can get access to a gateway installation spot that gives you a reasonable coverage for your intended devices. You will need power and in Malaysia, make plans for protection from lightning.

If you’re deploying a LoRa network in a city environment, make sure you have continued access to your gateway. A janitor could simply flip a switch to your gateway and ruin your weekend. NB-IoT does not require additional physical infrastructure and the telco is responsible to ensure good quality of service.

As a device maker, sometimes we play the role of a hesitant network provider of LoRa. This is one of the reasons we welcome NB-IoT.

Sensor density

If you’re a university, LoRa makes great economic sense. All your sensors are within your property and you can decide where on your building you’d like to install a gateway.

If you’re a highway operator, you would have distributed devices. It makes no economic sense to have a gateway for every two or three devices.

Data rate

LoRa has an interesting method of adjusting data rate depending on the signal strength. Lora has a feature called Adaptive Datarate (ADR). This feature will determine which SF is better to be used for current signal strength received by the node. If the signal strength is weak, the higher SF is selected (reduced data rate) and vice versa. In general, the LoRA data rate is much lower than NB-IoT but LPWAN aren’t designed for high data rate devices, it’s for small bytes of data.

Battery life

The data rate from NB-IoT comes at a cost as it uses more battery due to the higher transmit and receive power. If you need longer battery life, LoRa has better performance.

Conclusion

There are going to be times when LoRA is the right solution and there will be times when NB-IoT is the right one. I expect to see more devices from both connectivity model.

• Disclaimer 1: This is written based on our experience in Malaysia. We’re in early adoption phase of NB-IoT in Malaysia with scarce coverage.
• Disclaimer 2: We don’t have working experience with Sigfox, another LPWAN technology available in Malaysia.