“Wireless AMR system using ZigBee technology”

By

Sarang D. PatilUnder the Guidance of Prof. S. N. Pawar

Department of Electronics & Telecommunication

Topics to be covered

• Problem statement• AMR system• AMR system structure & types• Brief introduction to ZigBee technology & 802.15.4

standard• ZigBee architecture• ZigBee devices overview• System block diagram & Ckt. Diagrams• Flowcharts for server client & microcontroller• Demo of the system

Problem statement

• Present energy measurement system is

error prone & highly inaccurate.

• Errors gets introduced in every stage of

measurement• Present system is also not environment

friendly• Electromechanical meters can easily get

manipulated

AMR system

• AMR system provides solution to all above problems

• It is a technology which collects consumption, diagnostic & status data from metering devices & transfers that data to central system for billing or analysis

• Two types of AMR system– Wired AMR system

• Based on RS485 BUS

– Wireless AMR system• GSM based• ZigBee based

Requirements of AMR system

• Low Power consumption• Large no of devices in Single network• Ability to add or remove devices• Range of the devices• Free to use technology• All these requirements are fulfilled by

ZigBee

Structure of wireless AMR system

Why ZigBee only ??

• Low Power consumption• Ability of device to stay sleep• Ability to add or remove devices• Ability to mesh network• Large battery life(approximately 2 years &

above)• Device range up to 100 meters• Free to use

What is ZigBee?

•ZigBee is wireless networking technology.

•It is based on IEEE802.15.4 standard.

•ZigBee technology is a low data rate, low power

consumption, wireless networking protocol targeted

towards automation and remote control applications.

•Developed by ZigBee Alliance.

IEEE 802.15.4 standard

• Simple packet data protocol for lightweight wireless

networks(up to 250Kbps)

• Specifies the Physical (PHY) and Medium Access

Control (MAC) layers for Multiple Radio Frequency (RF)

bands(868MHz, 915MHz, & 2.4GHz).

• It is designed to provide reliable data transmission up to

100 meters or more

• ZigBee technology takes full Advantage of this standard

802.15.4/ZigBee Architecture

IEEE 802.15.4 MAC

IEEE 802.15.4

2400 MHz

PHY

IEEE 802.15.4

868/915 MHz

PHY

• Packet generation• Packet reception• Data transparency• Power Management

• Channel acquisition• Contention mgt• NIC address• Error Correction

Application

ZigBee• Application Support Sub Layer• Network Layer

ZigBee Architecture (contd..)

• PHY layer and MAC layer are defined by IEEE 802.15.4

• Physical layer concerns with interface with physical

medium(radio)

• It exchanges data bit with physical medium

• Also with MAC layer

• MAC layer is responsible for addressing of data

• For outgoing data it determines destination address of

data

• For incoming it tracks from where data is coming

ZigBee Architecture (contd..)

• Network layer(NWK) handle network addressing and routing its functions are:• Starting network• Assigning network address• Adding devices to and removing devices from network• Routing messages to their intended destinations• Applying security to outgoing messages

• Application support sub layer(APS) is responsible for communication with relevant application.

ZigBee Channel Allocation

• 868MHz / 915MHz • PHY

• 2405MHz

• 868.3 MHz

• Channel 0 • Channels 1-10

• Channels 11-26

• 928 MHz• 902 MHz

• 5 MHz

• 2 MHz

• 2.4 GHz

• PHY

2475MHz

ZigBee Devices

• ZigBee network has 3 types of devices– ZigBee Coordinator(ZC)

• Backbone of entire network• Act as Bridge between 2 networks

– ZigBee Router(ZR)• Optional network component• Participates in multi hop routing of packets

– ZigBee End Device(ZED)• can communicate only with coordinator• Does not participate in routing

ZigBee topologies

Wireless AMR system block Diagram

ZigBeeReceiver

Zigbeereceive

r

ZigBee to TCP/IP

conversionSERVER

Digital meter 1

Digital meter 2

Microcontroller (reading converter)

ZigBee transmitter

Microcontroller (reading converter)

ZigBee transmitter

• Digital meter counts units consumed in the form of pulses

• these pulses are given to microcontroller.• Microcontroller gives this data to Zigbee module.• Zigbee module transmit it in 2.4 GHz band.• Zigbee receiver receives it.• This data packets are converted into TCP/IP packets

through PC• All these data packets are collected at server and

added user’s account.

Block Diagram explanation

Transmitter section

• Digital meter is connected to microcontroller pin RA0.• Digital meter gives reading in the form of pulses.• These pulses are counted in microcontroller PIC16F77 and

appropriate reading is generated.• Microcontroller sends this data to Zigbee module ZMN2405HPC

serially.• Zigbee module is connected to microcontroller through pin RB1 &

RB2.• External flash ROM ST2404is connected to microcontroller at RD0

& RD1 to store data. • LCD display is connected to display process performed by

microcontroller.• LCD operates on 4bit data mode.• To supply power to this circuit 5V DC power supply is designed

separately.

Explanation of Transmitter Circuit

Receiver section

System’s main components

• LM 7805

• MAX-232

• ZMN2405

• PIC16F77

Features of PIC16F77

Operating Frequency DC - 20 MHzRESETS POR, BOR FLASH Program Memory (14-bit words)

8K

Data Memory (bytes) 368Interrupts 12I/O Ports Ports A,B,C,D,ETimers 3Capture/Compare/PWM Modules 2Serial Communications SSP, USART8-bit Analog-to-Digital Module 8 Input ChannelInstruction Set 35 InstructionsPackaging 40-pin PDIP

Features of ZMN2405Operating Frequency Range 2405 to 2475 MHzOperating Frequency Tolerance -300 to 300 kHzSpread Spectrum Method Direct SequenceModulation Type O-QPSKNumber of RF Channels 15RF Data Transmission Rate 250 kb/sSymbol Rate Tolerance 120 ppmRF Channel Spacing 5 MHzUpper Adjacent Channel Rejection, +5 MHz 41 dBLower Adjacent Channel Rejection, -5 MHz 30 dBMaximum RF Transmit Power 17 dBmOptimum Antenna Impedance 50 Ω

START

CREATE SERVER SOCKET

IS LOG FILE IS CREATED

CREATE LOG. TXT FILE

C

IS COMM PORT IS CONNECTED STOP

GIVE IP ADDRESS OF SERVER

IS CONNECTION IS ESTABLISHED

START

CREATE SERVER SOCKET

IS LOG FILE IS CREATED

CREATE LOG. TXT FILE

SWITCH TO TCP SERVER LISTEN MODE

CREATE NEW SOCKET CONNECTION

IS CONNECTION IS ESTABLISHED

GET DATA FROM CLIENT

AB

C

SEND IP ADDRESS TO SERVER

SEND DATA TO SERVER

IS SWITCH IS PRESSED

UPDATE DATALOG FILE

SEND DATA TO SERVER

IS STOP BUTTON IS PRESSED

CLOSE CONNECTION

STOP

A

IS CLOSE BUTTON IS PRESSED

TERMINATE ALL CONNECTIONS

CLOSE SERVER

STOP

B

Experimental results of the system

Coverage performance

Power consumption of the system

• Power consumption of only coordinator has been measured

• It is always in sleep mode

• It remain active only for 100mS for reception of data

power consumption

In active mode:

33 mA x 100ms / (60 x 60 x 1000)

= 0.0091 µAH

In sleep mode

3µA x 30 minutes/60

= 1.5 µAHstate Voltage current

active 5V 33mA

Sleep 5V 3µA

Publications• IJECET(impact factor 3.5930(calculated

by GISI)) (ISSN 0976 – 6472(Online)) Volume 3, Issue 2, July- September (2012), pp. 107-115

• IJERT (ISSN: 2278-0181) (Vol. 1 Issue 4, June – 2012)

• IJ-CA-ETS(ISSN: 0974-3596 ) ( APRIL 2012- SEPTEMBER 2012 | Volume 4 : Issue 2)

Interactive session

Thank you