wireless sensor networks using zigbee and wifi

Wireless Sensor Networks for

Microclimate

Telemonitoring using ZigBee and

WiFi

Y SUNIL RAJ KUMAR

MTECH ECE,

REG NO 14043029

DEPT OF ELECTRONICS ENGINEERING,

PONDICHERRY UNIVERSITY

ABSTRACTWireless Sensor Network is increasingly popular in the field of

microclimate monitoring due to its promising capability. Wireless

Sensor Network using many wireless communication protocols, such

as Bluetooth, ZigBee, ultra wideband, and WiFi. WiFi has many

advantages, i.e. high data rate and long range distances, but it

requires a high power. ZigBee uses less power, but it offers low

data rate and short range distances. This paper presents the

application of ZigBee and WiFi networks for microclimate

monitoring. Data of air temperature and humidity are collected

using ZigBee-WSN and then the data are transmitted from the

observed area to the monitoring center using WiFi transceiver This

system needs ZigBee – WiFi interface that convert the data format

from ZigBee protocol into TCP/IP protocol. Maximum distance

communication of ZigBee protocol is ± 200m in the outdoor area

with many obstacles.

17/04/15Credit seminar ,Dept of electronics

engineering, Pondicherry University2

CONTENTS• Wireless Sensor Networks

• IEEE 802 standards

• WiFi (802.11)

• ZigBee [802.15.4]

• Comparative Study of WiFi and ZigBee

• SYSTEM DESIGN

• Flow chart of data collection using Xbee Pro

• Flow chart of data processing in coordinator

node



CONTENTS

• Block diagram of zigbee and WiFi networks interface

• ZigBee transceiver

• WiFi transceiver

• Flow diagram of ZigBee to WiFi interface

• Conclusions

• References



Wireless Sensor Networks



• Mesh Coordinator: An entity that manages the

mesh network. It refers to the root of the logical

tree of a mesh network whose tree level equals

zero.

• End Device: A device that is not capable of

relaying data frames for other devices.

• Consider WiFi as a Mesh/Network Coordinator.

• Zigbee as a Coordinator.

• Sensor act as End device.



IEEE 802 standards



WiFi (802.11)

• Goals:

• To deliver services in wired

networks

• To achieve high throughput

• To achieve highly reliable data

delivery

• To achieve continuous

network connection.



WiFi [802.11] protocol architecture



Channels• 2.4GHz (802.11b/g/n)

• 13+1channels designated in the 2.4G Hz range

spaced5MHz apart(with the exception of a 12MHz

spacing before Channel14).

• Using only channels1,6,11,and 14 is

recommended to avoid interference



ZigBee [802.15.4]

• Low cost

• Low power consumption

• Low data rate

• Relatively short transmission range

• Scalability

• Reliability

• Flexible protocol design suitable for

many applications



ZigBee Protocol Architecture



PHY868MHz / 915MHz / 2.4GHz

MAC

Application

NetworkStar / Mesh / Cluster-Tree

Security32- / 64- / 128-bit encryption

API

ZigBeeAlliance

IEEE 802.15.4

Customer

Operating frequency bands

The standard specifies two PHYs 868 MHz/915

MHz direct sequence spread spectrum (DSSS)

PHY (11 channels)

1 channel (20Kb/s) in European 868MHz

band

10 channels (40Kb/s) in 915 (902-928)MHz

ISM band



2.4 GHz

Channels 11-26

2.4835 GHz

5 MHz

2.4 GHz

PHY

Comparative Study of WiFi and ZigBee



Standard Zigbee WIFI

IEEE Spectrum 802.15.4 802.11 a/b/g

Frequency band 868/915 MHz,2.4GHz 2.4GHz, 5GHz

Max signal rate 250Kb/s 54 Mb/s

Nominal Range 10-100m 100

Number of RF channels 16 14

Channel bandwidth 0.3/0.6MHz 22MHz

Modulation type BPSK,QPSK BPSK,QPSK,M-QAM

Spreading sequence DSSS DSSS,OFDM

Max no of cell Nodes >65000 2007

Authentication CBC-MAC WAP2(802.11i)

Data protection 16-bit CRC 32-bit CRC

Extension of basic cell Cluster tree, Mesh ESS

SYSTEM DESIGN



SENSOR NODE 1

SENSOR NODE 2

SENSOR NODE 3

Human

Interfaceing

Monitoring

system

WIFI

Transreceiver

ZIGBEE-WIFI

INTERAFACE

ZigBee Node Topology



A (CN)

C

D

EF

B

• The first part ZigBee (Z-WSN) that consist five

sensor nodes, the second part is the design of

ZigBee

• Data of air temperature and humidity are

collected using ZigBee-WSN and then the data

are transmitted from the observed area to the

monitoring center using WiFi transceiver. This

system needs ZigBee–WiFi interface that convert

the data format from ZigBee protocol into TCP/IP

protocol.





Flow chart of data collection using Xbee Pro

Flow chart of data processing in

coordinator node



Block diagram of zigbee and WiFi

networks interface

• ZigBee and WiFi interface which convert the

data from ZigBee protocol to TCP/IP protocol

and applies vice versa.



• ZigBee-WiFi interface consists of several

parts

A. ZigBee transceiver

B. WiFi transceiver

C. serial interface circuit port

D. (DB9)

E. MAX232 IC

F. power supply



ZigBee transceiver

• Xbee PRO: Global operation in the

2.4GHz frequency band according

to IEEE 802.15.4

• Regional operation in the 915Mhz

(Americas) and 868Mhz (Europe)

• Frequency agile solution operating

over 16 channels in the 2.4GHz

frequency





• Incorporates power saving mechanisms for all device

classes, plus support for battery-less devices

• Discovery mechanism with full application

confirmation

• Pairing mechanism with full application confirmation

• Multiple star topology and inter-personal area network

(PAN) communication

• Various transmission options including broadcast

• Security key generation mechanism

• Utilizes the industry standard AES-128 security scheme

• Supports Alliance standards or manufacturer specific

innovations

WiFi transceiver

• WIZ110SR is a gateway

module that converts RS-232

protocol into TCP/IP protocol.

• It enables remote gauging,

managing and control of a

device through the network

based on Ethernet and

TCP/IP by connecting to the

existing equipment with RS-

232 serial interface



Protocol Architecture



Flow diagram of ZigBee to WiFi interface



CONCLUSIONSNetwork which has been designed is work properly where

ZigBee Wireless Sensor Networks can collect the data of

air temperature and humidity from certain area, air

temperature sensors Using mesh topology, when one of

the node is off, then the others nodes can still sent the

data. Data from Z-WSN then convert to TCP/IP format

using ZigBee and WiFi interface. Finally, the data sent

from monitored area to the monitoring center using WiFi

transceiver based on point to point communication.

Maximum distance communication of ZigBee protocol is ±

200m in the outdoor area with many obstacles.



REFERENCES[1] Firdaus, Ahriman, Rois Akbar, Eko Nugroho Wireless Sensor Networks

for Microclimate Telemonitoring using ZigBee and WiFi ,2014 IEEE

conference on Aerospace and Remote Sensing Technology.

[2] Peng Yu; Xu Yong; Peng Xi-yuan, "GEMS: A WSN-based greenhouse

environment monitoring system," Instrumentation and Measurement

Technology Conference (I2MTC), 2011 IEEE, vol., no., pp.1,6, 10-12 May

2011.

[3]http://www.wiznet.co.kr/UpLoad_Files/ReferenceFiles/W5100_Datash

eet_v1.2.2.pdf.

[4]http://www.zgbee.org/zigbee-for-developers/network-

specifications/zigbeepro.

[5]N.Selvi, M.S.Balamurugan, Design And Control Of Internet Of Things

Enabled Wireless Sensor Networks‟, International Journal Of Engineering

Sciences & Research Technology (IJESRT) in 5th Jan 2014 issue ISSN: 2277-

9655



http://www.wiznet.co.kr/UpLoad_Files/ReferenceFiles/W5100_Datasheet_v1.2.2.pdf

http://www.zgbee.org/zigbee-for-developers/network-specifications/zigbeepro

wireless sensor networks using zigbee and wifi

Engineering

zigbee wifi interface

theapplication of zigbee

pondicherry university11zigbee

pondicherry university8wifi

pondicherry university6ieee

pondicherry university7wifi

standards wifi

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