“Wireless AMR systemusing ZigBee technology” By Sarang D. Patil Under 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 powerconsumption, wireless networking protocol targetedtowards 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 Application • Application Support Sub Layer ZigBee • Network Layer • Channel acquisition • Contention mgt IEEE 802.15.4 MAC • NIC address • Error Correction IEEE 802.15.4 IEEE 802.15.4 • Packet generation • Packet reception 868/915 MHz 2400 MHz • Data transparency PHY PHY • Power Management
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 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
Wireless AMR system block Diagram Microcontroller ZigBeeDigital meter 1 (reading converter) transmitter Zigbee ZigBee receive Receiver r Microcontroller ZigBeeDigital meter 2 transmitter (reading converter) ZigBee to SERVER TCP/IP conversion
Block Diagram explanation•Digital meter counts units consumed in the form ofpulses• 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 packetsthrough PC•All these data packets are collected at server andadded user’s account.
Explanation of Transmitter Circuit•Digital meter is connected to microcontroller pin RA0.• Digital meter gives reading in the form of pulses.•These pulses are counted in microcontroller PIC16F77 andappropriate reading is generated.•Microcontroller sends this data to Zigbee module ZMN2405HPCserially.•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 bymicrocontroller.•LCD operates on 4bit data mode.•To supply power to this circuit 5V DC power supply is designedseparately.
System’s main components• LM 7805 • ZMN2405• MAX-232 • PIC16F77
Features of PIC16F77Operating Frequency DC - 20 MHzRESETS POR, BORFLASH Program Memory (14-bit words) 8KData 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 START CREATE SERVER CREATE SERVER SOCKET SOCKET IS LOG FILE IS IS LOG FILE IS CREATED CREATED CREATE LOG. TXT FILE CREATE LOG. TXT FILE SWITCH TO TCP SERVER LISTEN MODE IS COMM PORT IS CREATE NEW SOCKET CONNECTED STOP CONNECTION GIVE IP ADDRESS OF SERVER IS CONNECTION IS ESTABLISHED IS CONNECTION IS ESTABLISHED GET DATA FROM CLIENTB A C
C AB SEND IP ADDRESS TO SERVER IS CLOSE SEND DATA TO SERVER BUTTON IS PRESSED IS SWITCH IS PRESSED TERMINATE ALL CONNECTIONS UPDATE DATALOG FILE SEND DATA TO SERVER CLOSE SERVER IS STOP STOP BUTTON IS PRESSED CLOSE CONNECTION STOP
Experimental results of the system Coverage performance
Power consumption of the system• Power consumption of power consumption only coordinator has In active mode: been measured 33 mA x 100ms / (60 x 60 x• It is always in sleep 1000) mode = 0.0091 µAH• It remain active only for In sleep mode 100mS for reception of data 3µA x 30 minutes/60 = 1.5 µAH state 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)