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Computing => Networking & Wireless => Topic started by: FredMorgan on May 11, 2021, 08:15:23 am

Title: What is the difference between LoRaWAN and NB-IoT?
Post by: FredMorgan on May 11, 2021, 08:15:23 am
1. Ecosystem
LoRaWAN is supported by the LoRa Alliance, an open non-profit association composed of more than 500 members. Its members work closely together and share experiences, promote and promote the success of the LoRaWAN protocol, and become the leading and open global standard for secure, carrier-grade Internet of Things LPWAN connections.

NB-IoT is supported by two telecommunications standards associations, 3GPP and GSMA, both of which have the same goal of promoting the interests of mobile networks and equipment.

2. Spectrum
LoRaWAN is optimized for ultra-low power consumption and remote applications. Therefore, network operators and equipment manufacturers can access the networks running on the license-free ISM Sub-1GHz spectrum for free.

NB-IoT uses a cellular spectrum network, which is optimized for spectrum efficiency. The licensing fee for frequency band usage is very high, and it is limited to a few operators.

3. Deployment status
According to the LoRa Alliance, 83 public network operators in 49 countries are currently using LoRaWAN, and more private companies are also using LoRaWAN networks.

GSMA is an organization representing the interests of NB-IoT, LTE and other mobile networks. According to it, 40 countries will launch NB-IoT networks in the future.

4. Deployment options
LoRaWAN network provides highly flexible deployment. It can be installed in a public, private, or mixed network, indoor or outdoor. LoRaWAN signals can penetrate into urban infrastructure, and each gateway can cover 30 miles (approximately 48.3 kilometers) in an open rural environment.

NB-IoT uses LTE cellular infrastructure, which is an outdoor public network and requires the deployment of 4G/LTE cellular towers. If the sensor exceeds the coverage area of the base station, the base station is not easy to move.

5. Protocol
The LoRaWAN protocol sends data asynchronously, and the data is sent only when needed. This can extend the battery life of the sensor device up to 10 years, and the battery replacement cost is low.

NB-IoT needs to maintain a synchronous connection to the cellular network, regardless of whether it needs to send data. For sensor devices, it consumes a long battery life, resulting in high battery replacement costs, which may be too costly in many applications.

6. Emission current
LoRaWAN provides 18 mA emission current at 10 dBm, and 84 mA emission current at 20 dBm. Modulation differences can enable LoRaWAN to support very low-cost batteries, including button batteries. 

The NB-IoT sensor consumes ~220 mA at 23 dBm and 100 mA at 13 dBm, which means that it needs more power to operate and requires more frequent battery replacement or a larger capacity battery.

7. Receive current
LoRaWAN provides lower sensor BOM cost and battery life for remote sensors. The receiving current is about 5 mA, and the overall power consumption is reduced by 3-5 times. 

The NB-IoT receiving current is about ~40 mA. The communication between the cellular network and the device consumes more than 110 mA on average, and a communication lasts for tens of seconds. The protocol overhead has a significant impact on the battery life of devices that need to work for 3, 5, or 10 years or more.

8. Data rate
LoRaWAN data rate is about 293 bps-50 kbps. The LoRaWAN protocol dynamically adjusts the data rate according to the distance between the sensor and the gateway, thereby optimizing the air time of the signal and reducing conflicts.

The peak data rate of NB-IoT is about 250 kbps, which is more suitable for use cases with higher power budget and higher data rate (above 50 kbps).

9. Link budget
LoRaWAN's MCL signal varies according to regional regulatory restrictions. The link budget is between 155 dB and 170 dB. 

NB-IoT needs to repeat remote sensors at a low bit rate in order to be able to support remote sensors. The link budget is up to 164 dB.

10. Mobility
LoRaWAN can support mobile sensors to track the movement of assets from one place to another. Even without GPS, high enough accuracy can be obtained for many applications.