One of the biggest issues facing the Internet of Things (IoT) device market today is its high fragmentation. The multitude of communication devices and protocols make it very difficult to build a uniform and functional system if you decide to use components from different manufacturers. There are many reasons for this, and they are not always just about the desire of designers to license their own solutions. The term IoT covers many types of devices. For example, these may be small measurement sensors powered by alternative energy sources and requiring low data exchange over long distances, but also remote cameras transmitting high resolution images in real time. Thus, the specificity of the designed device obliges designers to select the appropriate wireless communication technology, suited to the requirements of the designed device. You have to take into account, among other things, the battery life, the communication range or the amount of data transferred. Responding to the needs of the market, makers of development kits (including the Arduino platform) have ensured that their portfolio best covers the needs of IoT device designers. In this article, we present a brief overview of selected Arduino development kits from the MKR family, prepared for rapid prototyping of IoT devices using wireless communication in standards such as WiFi / Bluetooth, LoRaWAN / Sigfox, GSM / 3G or NB-IoT.
WiFi / Bluetooth communication with Arduino MKR 1000/1010
Communication in the 2.4 GHz ISM band, using WiFi and Bluetooth standards, has been present in the IoT device market for several years. For the rapid implementation of hardware and software prototypes using WiFi communication, Arduino has developed the Arduino MKR WiFi 1000 and MKR WiFi 1010 development kits. The former is based on the ATSAMW25 module, containing the SAMD21 microcontroller, the WINC1500 radio path and the ECC508 authentication chip. The MKR 1010 kit is equipped with the NINA-W102 radio module from u-blox, which offers Bluetooth / BLE communication.
On the software side, Arduino provides the WiFi101 library, supporting WEP and WPA2 Personal encryption, for the MKR WiFi 1000 modules. For the MKR WiFi 1010 module (and other kits based on the u-blox NINA-W102 module, y including Arduino NANO 33 IoT), the manufacturer has prepared the WiFiNINA library, as well as a number of sample applications demonstrating integration with Android IoT Cloud and Azure, AWS IoT Core, Google Firebase or Blynk.
LoRaWAN and Sigfox communication – Arduino MKR WAN 13×0 and FOX 1200 modules
The rapid development of IoT systems has led to increased interest in the topic of smart cities. Unfortunately, the WiFi / Bluetooth / BLE standards are used over short distances and do not meet all the requirements set for “Smart City” projects (which include, among others, extensive networks of pollution sensors, surveillance sensors water level or parking sensors). The solution to these problems can be the use of one of the two most popular communication standards in the LPWAN (Low Power Wide Area Network) – LoRaWAN or Sigfox, which allow small amounts of data to be transmitted over long distances. For rapid prototyping of devices using LoRa / LoRaWAN, communication, Arduino designers have prepared the MKR WAN 1300 development kit and its successor MKR WAN 1310. Both modules are based on the Atmel SAMD21 microcontroller, used in other modules of the Arduino MKR series, and the Murata CMWX1ZZABZ radio module. The new version of the module is also equipped with 2MB Flash memory, a new battery charging circuit and optimized power circuits with low consumption.
MKR 13×0 WAN the modules work with the Arduino IoT Cloud supplied by the manufacturer. The complexity of the solutions provided is complemented by LoRa Arduino Pro Gateway connectivity optimized for MKR WAN 1310 modules.
An interesting alternative to LoRa / LoRaWAN is the Sigfox standard, which places particular emphasis on communication between nodes and the access gateway. The Arduino MKR FOX 1200 module, based on the Atmel SAMD21 microcontroller, was made available to designers. the ATA8520 RF smart chip, tuned to the 868 MHz ISM band allocated for Europe, is responsible for radio communication.
GSM / 3G communication – Arduino MKR GSM 1400 module
Even a large mesh network running in LoRa / LoRaWAN technologies is currently unable to provide global coverage. In the case of IoT projects requiring an almost unlimited communication range, the best solution is to use the GSM / 3G standard. Arduino prepared the MKR GSM 1400 module for GSM / 3G communication with a SARA-U210 modem by u-blox and a Microchip ECC508 secure authentication module for implementing communication security mechanisms. The integrated GSM modem operates in the following frequency bands: GSM 850 MHz, E-GSM 1900 MHz, DCS 1800 MHz and PCS 1900 MHz.
To improve the software development process, the manufacturer provides the MKRGSM library (which saves the programmer from using the module using low-level AT commands), as well as a rich set of examples (including GPRS communications , receiving / sending text messages, managing voice calls). The MKR GSM 1400 module can work with both Arduino IoT Cloud software and alternative cloud solutions: Google IoT Cloud, Blynk or SORACOM Air IoT, for which the manufacturer has prepared a set of example implementations.
Narrowband IoT Communication – Arduino MKR NB 1500 Module:
When briefly characterizing the selected communication standards for IoT devices, it is impossible to ignore solutions based on the Narrowband IoT (NB-IoT) standard, which use the licensed LTE 800 MHz band for Communication. Like LoRaWAN and Sigfox solutions, NB-IoT belongs to LPWAN networks, thus ensuring stable communication over large areas through the use of energy-saving radio modules that ensure many years of battery operation. Thus, it offers another alternative to LoRaWAN and Sigfox communication in “Smart City” solutions.
For the rapid prototyping of NB-IoT end nodes, Arduino prepared the MKR NB 1500 kit, equipped with the u-blox SARA-R410M-02B module, enabling LTE Cat M1 / NB1 connectivity in the following frequency bands: 1, 2, 3, 4, 5, 8, 12, 13, 18, 19, 20, 25, 26 and 28. In addition, MKR NB 1500 kit is equipped with ECC508 Microchip authentication chip, Micro SIM card connector, Li-Po battery charge controller and external antenna connector.