ZIGBEE TECHNOLOGY

                                  

OBJECTIVES :

what is Zigbee technology.

Zigbee applications.

purpose of ZigBee technology.

generals  characteristics of ZigBee standards.

operating frequency band.

 

ZigBee is a wireless technology standard that defines communication protocols for short range communication . ZigBee standard is specially build for control and sensor networks. WIFI and Bluetooth are not suitable for this short range communication..

what is ZigBee

ZigBee is a standard that addresses the need of very low-cost implementation of low power devices with low data rates for short range communication .

*It is most commonly used in IOT(Internet of things) 

ZigBee applications

                            

home automation .

medical data collection. 

industrial control system.

and many more..

home automation:

basically have home automation network with software application that control the devices.

the controller called heart of that whole network..
gateway is the interface between  ZigBee network and web . the gateway is connected to the internet and it will led the home owner to control his/her devices virtually anywhere from the world..

example of sum supported devices

lights, door locks, switches ,smoke detectors , fans , appliances , and etc..

another interesting ZigBee network is  remote monitoring systems 

                                   

here a patient wearing some ZigBee network can collect information such as B.P(blood pressure), body temperature  ,heart rate. etc this information can be sent thorough the  gate way over the internet to the personal computer of the hospital so that doctor / nurse can monitor patient health condition .  

you may have dout that why we cannot use WIFI and Bluetooth for this kind of devices because WIFI use more power and high data rate which is the bad news for the devices where low battery consumption is important  examples sensors ..

Bluetooth is not a good choice it support maximum 7 devices where as the ZigBee supports hundred's of devices 

general  characteristics of ZigBee technology standards 

     

 

low power consumption'

devices can typically can operate for several years on a single battery the devices spends most of the time in power saving mood also known as sleep mode

low data rates

the data rates is about 20kbps-250kbps however this low data rates is sufficient where zibee is intended for. when comparing with WIFI :11mbps , Bluetooth : 1mbps

short range

the distance up to 75-100 meters indoor.

and 300+  meters (line of sight) or even more..

network joining time:

ZigBee takes 30msec to join a network when comparing with Bluetooth up to 10 sec and WIFI about 3 sec to join a network

support small and large networks :

ZigBee connects 65000 devices in a network (theoretically)

practically it connects 240 devices and WIFI support up to 32 devices ,Bluetooth up to 7 devices

low cost of products and cheap implementation reason for simplicity of technology 

security

uses ACE cryptography algorithm for data encryption and data authentication .this is standard cryptography because most of the bank use this cryptography algorithm in online banking transactions 

operating frequency band

there are currently '3' frequency bands are assigned to ZigBee 

868 MHZ , channel '0' located in Europe

915 MHZ ,channel '1-10' located at Australia 

2.4 GHZ ,channel '11-26' across the world

only one channel should be selected  for the network