Low Power Wide Area Networks (lpwan): Technology Review And Experimental Study on Mobility Effect

LOW POWER WIDE AREA NETWORK (LPWAN): REVIEW

In this section we introduce the basics of LPWAN followed by discussion of different LPWAN technologies and their pros and cons. Then using LoRaWAN network as an example, we discuss the physical structure of LPWAN protocol and its network setup. We also look into different types of end nodes and how they communicate with the gateway.

1. OVERVIEW OF INTERNET OF THINGS

The Internet of Things is made up of very intelligent devices that communicate with each other to form a network [13]. These networks along with their software also include the hardware devices which collect environmental data and pass it among other devices. These devices can be used in various places to serve multiple purposes. Some of the examples of their applications as discussed in [16] are alarm systems, smoke detectors, smart meter, parking spot tracker, smart street lights, smart watches, human health monitoring, etc. The ever-growing interest in the IoT goes side by side with the decreasing prices of IoT devices over the years.
The communication frequency for IoT devices ranges from 13.56MHz, for applications like contactless payments [39], to 2.4GHz or more for applications that need video streaming. Apart of excluding some of the technologies [20], most of the LPWAN technologies operate in ISM (Industrial, Scientific and Medicine) SubGHz bands. Operating at lower frequencies gives a log of different characteristics when it is compared to those technologies that operate at higher frequencies. The concrete construction in an urban area have less effect on low frequency signal as compared to high frequency signal. It has been also explained in [49] as to how operating in Sub-GHz bands adds both reliability and robustness to the signal. This, combined with the minimal data rate modulation techniques, simple end node and cellular topology enables the IoT devices to transmit and receive data over long range and years.

2.