WIZnet has been running an IoT open house with SK Telecom to provide various technical support to companies who want to implement IoT in their business.

This article is a simple guide document on how Cat.M1 is being used among the IoT network.


[What is IoT?]


IoT is an abbreviation of Internet of Things, which refers to the services that can be provided over the network. If you look at the ad of current technology, the boiler in the house warms up the water before the owner arrives at home when the owner sends the information from a car or mobile phone. These services can be implemented over the internet and are referred to as IoT.

There are two main categories of networks, wired and wireless networks. WIZnet has the solutions for both, wired and wireless network. We provide WiFi, LoRa, LTE.Cat.M1 solution from the wireless.  I will explain about Cat.M1 with a simple example.


[SKT LTE Cat.M1]


LTE.CAT.M1 is a kind of LPWAN. LPWAN stands for Low Power Wide Area Network and refers to networks that can cover wide band with low power. LPWAN includes Lora, Cat.M1, Sigfox, and NB-IoT.

Cat.M1 used the existing LTE band and speeds up to 300kbs. (This information is based on the SK Telecom service provider in South Korea.)

The frequency uses three bands (Band 3, 5, 26). Although there is a difference in the voltage value depending on the module, the basic current consumption is 200mA at Tx, Rx, 5~6mA at idle, and 10uA at PSM.

The following link is an introduction of SKT LTE Cat.M1.


[IoT Black Box ‘AirTron’]

LTE Cat.M1 is a network released at the end of April this year. Application development has internally progressed and several products have been released. In this chapter, I will talk about IoT black box among these services.

When the other person cause an accident to a car parked in a parking lot, we normally find that there is something wrong with the car long after the accident happened and then check the black box in the car. To solve this problem, the ‘AirTron’ black box transmits an impact detection message to the mobile phone through LTE Cat.M1 module when the impact is detected in the vehicle. Furthermore, it supports the function of transferring the pictures taken from the black box front and rear cameras to the application. Also, when you don’t know where your car is parked in a large parking lot, you can find your car by transferring the location taken from the black box cameras.

As mentioned in the technical contents, the speed of Cat.M1 is 300kbps. It isn’t enough speed to send and receive pictures instantly. If you actually use the application to receive a picture and message, you can see that the message will be immediately sent upon the accident and the picture will be sent about 5 seconds later.



In addition to these applications, we are providing technical support for various services through the Open house, and we are also building support capabilities.

WIZnet can help you make the most affordable and efficient service implementation with the right combination of Ethernet solution in a wired network, short-range networks(BLE, WiFi) and long-range wireless networks(LoRa, LTE Cat.M1).