Application of the Internet of Things in Smart Homes Combining Various Wireless Technologies – ELE Times
There are a variety of wireless technologies available on the market, each with its advantages and disadvantages and its application fields. Combining the various advantages of wireless network technology will enable Internet of Things (IoT) devices to perform better. This paper describes certain features of wireless network technology and the advantages of solutions provided by Arrow Electronics.
ZigBee forms a network by combining mesh topology with gateways
ZigBee (802.15.4) and BLE (Bluetooth Low Energy) are the two most popular IoT wireless low-power protocols on the market, both of which have their own advantages and disadvantages. ZigBee is a mesh network protocol designed to transmit small amounts of data over medium distances. It operates on a mesh topology network, meaning that information from a single sensor node passes through a group of (or “mesh”) modes until transmission reaches the gateway.
ZigBee is a local area network (LAN). It is therefore the ideal protocol for home automation and smart lighting. Although ZigBee is broader in scope, it is still fairly limited and is not the best option for highly instrumented installations such as industrial IoT applications. The ZigBee network has higher latency due to its mesh topology, which can cause bottlenecks when multiple nodes attempt to reach the gateway through a single node.
Short BLE networking range and high data rate
BLE is a personal area network (PAN) designed to connect to devices near users, so BLE has much shorter networking range than ZigBee, but its data rate is much higher. BLE data rates in short bursts are 2 Mbit/s. BLE can “sleeps” between these short bursts, a feature that ZigBee does not have and requires less data and power usage.
Many BLE applications are designed to use smartphones as gateways, but this works only when a smartphone is present. Wearable devices such as smartwatches or fitness bands are also capable, but sensors used in commercial and industrial applications are often unattended, making smartphone gateways impractical or impossible to implement.
Build strong PANs and LANs with BLE and ZigBee
In fact, BLE and ZigBee can be complementary to each other. Some developers have found that a combination of BLE and ZigBee can create very powerful PAN and LAN devices.
Taking a smart door lock as an example, a user can open it via a BLE link using a smartphone. The same door lock can also be connected to a home router via ZigBee and controlled via an Internet connection. Thus, when the owner approaches the door, their smartphone uses a cellular network or Wi-Fi to communicate with the router and automatically opens the door using the ZigBee stack inside the router. However, if Internet connectivity is down, users can use smartphones to open door locks via BLE.
Reference design of IoT platforms supporting double protocols
Arrow Electronics also provides a reference design using STM32WB that supports Zigbee and BLE. The solution can support Zigbee and BLE stacks with the same hardware, and also integrates RF front end IC to enable modules to generate 20dBm outputs for long range applications, and reference applications can also be used to run Zigbee and BLE stacks concurrently.
STM32WB is a dual-core, multi-protocol and ultra-low-power 2.4GHz MCU system-on-chip. It supports BLE 5.0 and IEEE 802.15.4 protocols (in a single and concurrent mode) and covers a wide range of IoT application needs. The module is based on ST’s best-in-class …….