An article that takes you through understanding LPWA communication network technology

Jul 26 - 2022

lpwa standard

If you've been following the IoT scene more closely, lpwa standardyou've heard the term LPWA. Even if I haven't, I've seen LoRa, SigFox, and NB IoT in the technical press.

To meet the connectivity needs of more and more remote transmission devices, lpwa was born. lpwan (low power wide area network) is designed for iot applications with low bandwidth, low power, long distance and massive connectivity. Now let's get into today's topic and introduce lpwa technology to you.

1、SigFox

SigFox is a French IoT technology startup. Its company is called SigFox, and its technology is also called SigFox. sigFox technology is specially designed for low throughput projects. It has a low transmission power consumption of 50-100 microwatts, but still maintains a relatively stable data connection. But because IoT devices generate a lot of data, which is stored by SigFox itself. But SigFox is, after all, a small company, and its own custody of this data is not credible enough. It also has doubts about information security, so the use is not as wide as LoRa's.

2、LoRa

LoRa technology was developed by Semtech, and after the joint development efforts of LoRa Alliance, they developed a network called LoRaWAN for LPWA application. Lora can be widely used in automatic information meter reading, intelligent home and building automation, wireless early warning and safety education system, industrial production monitoring and control capability, and remote irrigation operating system analysis in China, etc.

3、NB-IoT

NB-IoT was first proposed by Huawei and Vodafone, and then joined by Ericsson and Qualcomm and other companies. It is characterized by NB-IoT being called narrowband cellular IoT, so it is built on existing cellular networks. Also, since it is narrowband and consumes only about 180KHz of bandwidth, it can be deployed directly in GSM networks, UMTS networks or LTE networks, reducing deployment costs and enabling smooth upgrades.

4. eMTC

The last described in lpwa technology is Ericsson based on 4g network solution emtc, which is mainly oriented to deep coverage and large connection application scenarios. Compared with nb-iot, it has the advantages of fast speed, small coverage and high power consumption. However, while it has a smaller coverage area and greater power consumption than nb-iot, it has the ability to communicate by voice. Therefore, compared with nb-iot, it can be used in certain situations where voice communication is required.

5. LPWA technology comparison

Next, this paper will also make a brief comparison of the above LPWA technologies. Except for NB-IoT and eMTC, the other two networks run on the SubG license-free band. subG refers to the frequency below 1GHz, mainly the band from 27MHz to 960MHz. subG is ideal for long-range low-power communication. For the same power, the higher the network frequency, the worse the penetration capability. However, LPWA field devices, such as electric meters and water meters, are often placed in deeper locations, and there are usually many obstacles on them, so it is essential to choose a low frequency band. It can also be seen from the table that in the description of NB-IoT, its frequency bands are mainly deployed above the licensed bands of SubG. This is because some NB-IoT networks are deployed outside the licensed bands of SubG. The specific reasons are explained in later sections of this paper. LoRa in unlicensed bands and NB-IoT in licensed bands are both popular LPWA technologies, so they are often used for comparison. The differences between the two are:

LoRa is designed by Semtech, an American company, and NB-IoT is a standard developed by 3GPP through the Mobile Network Communications Technology Association. For example, NB-IoT chip module structure is now being done by Huawei, Qualcomm, Samsung, MediaTek and other companies.

2) Different NB-IoT uses bands that are licensed bands, while Lora uses unlicensed bands. The licensed band is a frequency band approved by the Ministry of Industry and Information Technology, and other individuals, enterprises and institutions are not allowed to use it except for authorized operators, and it is illegal for the radio management department to check the water meter at the door. And non-authorized bands, is the Ministry of Industry and Information Technology did not say who use, who can use the band. Therefore, if individuals or enterprises use Lora's operating band for other purposes, it will cause serious interference to Lora devices in the area, resulting in unavailability of the network. Therefore, the NB IoT network with official background is certainly better and of higher quality.

3) Lora requires companies to build their own networks. nb-iot operators have built their own networks, but they do not operate Lora networks. If companies want to use Lora, they need to buy their own base stations, network equipment, servers and other network operation software and hardware, complete the network construction, and operate their own networks.

Currently, the three major operators of NB-IoT have completed the construction of base stations and network turn-up in China. Just like using cell phone SIM cards, enterprises only need to buy NB-IoT SIM cards from operators and then insert them into devices with NB-IoT modules and pay to use them.

4) What are the advantages of LoRa? In fact, we really have no technical advantage of LoRa for 90% of enterprise development. Unless an enterprise wants to use IoT in rural areas, remote mountainous areas, independent factories, etc. (such as China's smart family farms, smart city factories), it really can not be covered by the operator's NB-IoT network, so there is no choice but to think of self-built LoRa. Data for theft, so people prefer to choose their own culture to build social networks to manage themselves as maintenance, rather than trust the operators. The above issue is the big difference between NB-IoT and LoRa.

By:Carmen