Zigbee Smart Lighting Architecture | Zigbee Smart lighting basics

This use case covers basics of zigbee smart lighting architecture. It describes various elements of zigbee smart lighting architecture.

As we know zigbee is a low data rate and low range wireless technology. It works on two frequency bands viz. 2.4 GHz and 868/915 MHz. The zigbee devices consume less power and hence they can be deployed for longer duration without any battery charging or battery replacement. This has made zigbee technology to be used in lighting systems across the world.

zigbee smart lighting architecture

We already know that any zigbee system requires three elements coordinator, router and end devices. Let us understand various elements of zigbee smart lighting architecture as shown in the figure-1.

Zigbee Gateway:
• It consists of microprocessor (usually ARM or Intel), gsm/gprs SoC, zigbee SoC (System on Chip), wifi SoC, memory (flash memory, ROM, RAM) and other peripherals.
• Gateway has interfaces such as cellular, USB, RS232, Ethernet,Zigbee, WiFi etc.
• It supports protocols viz. HTTP, SoAP, RESTFUL etc.
• The upper layer protocols of zigbee stack run on Microprocessor while PHY and most of the MAC layer functionalities run on the zigbee SoC.
• About 300 gateways are needed to cover larger area of a city. One Zigbee gateway supports 200+ zigbee compliant end devices which are placed along with the street lights.

Zigbee based street lights:
• Each of the street lights consist of small zigbee modules. The lights are controlled remotely either from mobile or desktop applications running in a cloud.
•  The mobile app can interface with zigbee gateway using wifi or cellular connection.
• Hence based on distance either of these options are available with the user to have monitoring and control over entire smart lighting system.

Cellular connectivity:
• The zigbee smart lighting architecture provides connectivity with cellular wireless networks either GSM/UMTS and can also be integrated with LTE/LTE-advanced.
• As shown control of lighting system is also possible through desktop apps running in the cloud which utilizes MQTT or REST protocols.
• MQTT is broker based architecture while REST is bus based architecture. Refer MQTT vs REST and MQTT vs HTTP.

Advantages of Zigbee Smart Lighting

Following are the merit/benefits/advantages of zigbee smart lighting system.
• The zigbee nodes consume less power and hence once deployed street lights can last for 10 to 15 years.
• It is very easy to maintain and manage the smart lighting system with the help of GUI software in desktop or UI application in mobile.
• The maintenance of system can be done by any person with little training and highly skilled engineers are not needed. This will save labour costs.
• With the help of automatic dimming feature, electric companies can save large amount of vital power. This will help them avoid shortage of electric power when they do not have sufficient production capabilities to serve large population in metro and densed populated areas.
• The system can be operated from anywhere with the help of cellular internet connection.
• The software can be ported and changed very easily using remote connection. This will help seamless integration of zigbee smart lighting system with emerging wireless technologies such as LTE-advanced, 5G etc.

Zigbee Related Links

•  what is zigbee
•  Zigbee network architecture basics
•  Zigbee Protocol Stack
•  Zigbee Physical layers
•  Zigbee physical layer frame
•  Zigbee MAC layer frames
•  Zigbee frequency bands
•  Zigbee Gadgets
•  Zigbee Products

RF and Wireless Terminologies