Post on 04-Jul-2020
Automatic/Remote Meter Reading Copy right:YMPL, Udaipur
11/10/2010 1
Introduction to Automatic Meter Reading and Remote Meter ReadingBy:- Mr. Rajesh Nimare
Automatic/Remote Meter Reading Copy right:YMPL, Udaipur
11/10/2010 2
Utility solution of tomorrow
Metering is century old, Computing is several decades old and communication is new to realize the AMI dream
Automatic/Remote Meter Reading Copy right:YMPL, Udaipur
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AMI Technology = Comms technology
Changing customer needs, from products to system.
Automatic/Remote Meter Reading Copy right:YMPL, Udaipur
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How communication will impact customers?
• HAN: Communication between single meter and multiple In-Home devices.
• License free, interference tolerant wireless operation: Zigbee 2.4GHz
• Mesh architecture from Zigbee to combat interference.
• Other load control devicescan be controlled using different algorithms. HAN
Load
Control
IHD
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Agenda: Automatic Meter Reading
• Introduction to Automatic Meter Reading• Classification of Automatic Meter Reading• Basic model of Remote Meter Reading• PSTN based AMR• Wireless based AMR
– Fundamentals of radio transmission and reception– Low power radio / high power radio based RMR– GSM/ GPRS/ CDMA based RMR
• Physical connection
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Introduction to Automatic Meter Reading
• Automatic meter reading is the mechanism of collecting the meter readings (data) electronically.
• Not a new concept for Indian Utilities. (recall: when did you first heard MRI?)
• Components of AMR:• Electronic meter• A data collection mechanism• Media and its compatible Interface device
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Meter reading is much beyond just “KWH”
Modern electronic meter records three broad category of data.
Data for invoicing
1. Past month bill-point data.
2. Energy registers
3. Time Of Use
4. Average PF
5. Maximum demand
Historic data
1. Previous bill-points energy/ demand.
2. Load Profile for 6-10 parameters.
3. Programming/ configurations
Installation security data
1. Electrical parameters during meter reading.
2. Tamper and fraud recordings with date, time and snap-shots.
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11/10/2010 8
Utility management: Importance of Meter data
Meter Data
Invoicing and Billing Energy Audit Tariff formulation
Electricity Regulator
Engineering Actions
Load Research
Planning
Effective utilities have good data management system
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Meter readings are collected in two different ways
Manual reading1. Uses data recording
formats on paper.2. Only partial data is read.3. Prone to errors
Electronic using HHU1. Uses Hand Held Device
called as MRI.2. Reads data electronically.3. Data is checked for
transmission errors.4. No errors.
AMRA is an abbreviation of Automatic Meter Reader’s Association, mostly active in the USA (AMRA) , U.K. UKAMRA and Euro-AMRA.
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11/10/2010 10
The automatic meter reading
Automatic Meter reading
Local AMR
1. Uses Hand Held Device
2. Need to visit the site.
3. Time consuming.
Remote AMR
1. Uses telecommunication media
2. Meter can be read from a remote location
3. Saves on travel time and cost.
4. Improves productivity
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Benefits of Automatic (electronic) Meter Reading
1. Reliable data.2. Speed of collection.3. Electronic format hence easy interface to the next stage.4. Free from human intervention.5. Ability to collect load profiles, history and tamper details.6. Ability to “Up-load” changed configuration to the meter.7. Improves vigilance as the meter reader HAS to visit the
consumer, no coffee-shop reading.
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1. Save on regular "on-cycle" meter reading
2. Obtain more easily (and in some cases, instantly) initial and final meter readings for opening and closing accounts
3. Streamline high bill investigations
4. Flag potential high consumption before customers get a high bill
5. Help pinpoint system losses
6. Help detect theft of service
7. Enable more frequent readings with little incremental cost
8. Enable custom billing dates
9. Support customized rates (e.g., for large customers)
10. Provide detailed consumption information to customers
11. Provide watchdog services, like leakage monitoring
12. Improve cash flow management
13. Improve revenue forecasting, by tying detailed consumption information to production data and expected billings
14. Aid in rate design
15. Enable more sophisticated rates; i.e., that more closely track costs, or encourage conservation.
16. Improve meter management: ensure meters are properly sized; determine optimal time in service or cumulative registration
17. Reduce bill adjustments
Benefits of an AMR system
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Remote AMR = Remote Meter Reading
Definition: Collection of data from a meter from a remote location using telecommunications.
Components of RMR
Meter with communication
abilityCommunication
network.
Utility’s RMR
station
Reporting / bill printing
system
Wired
Wireless
RMR is characterized by the technology used for the “first hop”.
Media interface device
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Elements of RMR: Meter with communication ability.
•Meters provided with optically isolated transmitter (Tx) and receiver (Rx)
•Special meters having isolated “electrical” connectivity using RS232 or RS485 physical interface.
•Default and adaptable baud rate (Bits per second)
•Data structure
•Data security embedded (encryption of data)
•Quantum of data they provide (Pay-load)
Semi-duplex: Communication system in which the sender and receiver talks alternatively based on their “turn” to speak/ listen. Most of the meter communicate in “semi-duplex” manner same as we humans.
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Media Interface device
• An interface device which interconnects the communication media and energy meter.
• Decided by the communication media selected.
• Eg. Modems, GSM interface etc.
MID connected with the meter are called as “OUT STATION” MID.
MID connected at the utility PC is called as “IN STATION” MID.
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Elements of RMR: The communication media
Wired1. Telephone2. RS2323. RS485
Wireless1. Low power radio2. High power radio3. GSM
What is important for utilities is the selection between :
1. Public carrier like Airtel, BSNL etc
2. Create your own communication network
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RMR: Communication media selection criteria
1. Cost Y = mx + c (Check the upfront and running cost)
2. Reliability of communication
3. Tamper resistant4. Secrecy5. Immune to environmental/
man-made disturbances6. Ease of interface7. Application
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Transmission Protocols
– Simplex• Communication flow in one direction only –
broadcast television or radio.
– Half duplex• Capable of communication in both directions but
not at the same time – ‘walkie-talkies’
– Full duplex• Simultaneous two-way communication – the
telephone
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Communication Terminology
• Circuit-switched / connection oriented• Packet switched / connectionless
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Circuit Switching
• [historic definition] seeking out and establishing a physical copper path end-to-end.
• implies the need to first set up a dedicated, end-to-end path for the connection before the information transfer takes place.
• once the connection is made the only delay is propagation time.
PSTN
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Packet switching• Store-and-forward network where the block
of transfer is a complete packet. A packet is a variable length block of data with a tight upper bound.
Connectionless
1. No set up is needed.
2. Each packet contains information which allows the packet to be individually routed hop-by-hop.
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Store-and-Forward Networks
• Intermediate processors (IMPS, nodes, routers, gateways, switches) along the path store the incoming block of data.
• Each block is received in its entirety, inspected for errors, and retransmitted along the path to the destination. This implies one transmission time per hop.
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RMR Communication media: telephone network
Telephone network = Public Switch Telephone Network (PSTN)
Data Concentrator
Telephone Switch
Line card
Fiber
Other switche
s
Two telephone wires have their designation as Ring and Tip.
Data concentrator digitizes the voice @8000 samples
Dial tone is a combination of 350 and 440 Hz tone.
Normal telephony is analog based.
Belongs to the circuit switched system
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Modem: Media Interface device for PSTN
Digital dataAnalog
telephone line
Modem = modulator demodulator
Modem is needed wherever an analog system is to be connected to a digital
system
Power supplyISDN = Integrated Subscriber Digital
Network, hence does not need modem for PC/ Meter interface.
Modems allow set-up of their Baud-rate, data-frame, ring-counts and other error correction techniques using “AT” commands.
Configuration for in-station and out-station modems are different.
Automatic/Remote Meter Reading Copy right:YMPL, Udaipur
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) PSTN(دستکاه آر ام آر به اساس پی اس تی ان
RMR Station
Utility’s MIS
RMR Software package
Power supply
Power supply
Analog communication Digital communication
سويچ تيلفون
Energy Meter with communication facility
Digital communication
Meter reading calls are initiated by the utility: “Out bound dialing”.
SPD
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تناسب آر ام آر مبنی بر تيلفون
زيربنای موجود•قابليت اعتماد معقول•. نرخ ھای معين مناسب•برای تيلفون ھای که می آيند •
. مصرف ضرورت نيست
در معرض دست زدن توسط •مصرف کننده قرار دارد
مصرف کننده ممکن شماره را •از سی يو . (مصروف نکھدارد)جی استفاده کند
مخاطره خراب شدن بخاطر •جريان ھای سريع و غيرعادی
. و تغيير پوتانشيل زمين
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احتياط ھا ھنکام استفاده از آر ام آر مبنی بر تيلفون
موديم ھای درجه بندی شده برای استفاده خانګی و تجارتی برای استفاده آر ام •. مناسب نيستند) صنعتی(ار در بخش
6حواله برق موديم بايد قابليت مقاومت جريان ھای سريع و غيرعادی الی •. کی وی را داشته باشد
) مشابه به ميتر(٪ 30+٪ و 40-موديم بايد به بی ثباتی ولتاژھای وارده ميان •.محفوظ باشد
محافظت در مقابل جريان ھای سريع و غيرعادی برای لين ھای تيلفون تھيه •. نماييد
. تا حد امکان از لين ھای اختصاصی استفاده نماييد•
Automatic/Remote Meter Reading Copy right:YMPL, Udaipur
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ارتباط مخابره: وسيله آر ام آرارتباط به وسيله مخصوص
شبکه ارتباط را ھر وقتی که به آن 1.. نياز باشد، بنا نھاده ميشود
. نياز به کدام حمايت زيربنايی ندارد2.
مصارف مداوم به جز از بخش تنظيمی 3.. ندارد
محرميت4.
مخابره با / مخابره با نيروی پايان 5.. نيروی بلند
مبنی بر زيربنا. نياز به يک زيربنای ارتباطی دارد1.نياز به يک شرکت فراھم کننده 2.
خدمات مخابره دارد و بنابرين نياز . به ھزينه برای عملکرد دارد
بر اساس موافقت نامه با –محرميت 3.. فراھم کننده خدمات
سی دی ام ای ) / GSM(جی اس ام 4.)CDMA .(
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بنيادھای ارتباط با مخابره
فرستنده و ګيرنده الف فرستنده و ګيرنده ب
(KHz / MHz)) ميګاھرتز/ کيلوھرتز (فريکانس آله فرستنده و کيرنده بايد عين فريکانس باشد
. فريکانس اصالح شده حامل فريکانس انتقال می يابد/ فاز / خبر از طريق دامنه
از طريق ) کانال(بنابرين، اکثر اوقات ارتباط دو جانبه باالی عين فريکانس . ساحه فريکانس يک منبع نادر استبه صورت تخنيکی اين بنام سيستم دو جانبه تقسيم شده ). سيستم نيمه دو جانبه. (انتقال و اخذ به نوبت صورت ميکيرد
.ياد ميشود) TDD(زمانی تی دی دی
از الف به ب از ب به الف از الف به ب از ب به الف از الف به ب از الف به ب از ب به الف از الف به ب از ب به الف از ب به الف
زمان
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جھش فريکانس و ساحه کسترده
تکنيک ھای ساحه کسترده بسته ھا به فريکانس تغيير کننده انتقال •
. می يابندھر دو فرستنده و کيرنده نمونه جھش •
. فريکانس را ميدانندتصديق بازګشتی فرستاده شدن اطالع، •
. يا در غير آن انتقال دوباره معلومات
از الف به ب
از ب به الف
از الف به ب
از ب به الف
وقت بر حسب ملی ثانيه
کانال فريکانس
A B
Ok
NOK
OK*
درست است تکرار
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بودجه ارتباط راديو يا مخابره: فھميدن وسيله ارتباط
A Br
Ht Hr
A = 117 + 40 log D miles + 20 log F MHz – 20 log (Ht x Hr)
D
Fresnel Clearance Zone r = 43.3 x √ (d/4f)
.دارند dBmفرستنده ھا و ګيرنده ھای مخابره نيروی انتقال و حساسيت ګيرنده در
mW to dBm: dBm= 10log 10(milliwatt)
dBm to Watts: Watt = 10 ((dB-30)/30)
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آر ام آر مبنی بر مخابره با نيروی پايان
) انتقال(فرستنده و کيرنده dBm 10+: نيرو•قابل عيار شدن MHz 433: فريکانس•داخلی : آنتن• FHSS: نوع ساحه ګسترش• RF :(10 mW(توليد نيروی آر اف •
) دريافت کننده(فرستنده و کيرنده dBm 105-: حساسيت•قابل عيار شدن 433MHz: فريکانس•داخلی: آنتن• FHSS: نوع ساحه کسترش•
ميتوانند در ) 105dBm-و 10dBm+(با استفاده از آنتن جھتی فرستنده و کيرنده فوق الذکر ھرچند، اشيای متحرک و ساير تضعيف ھا بايد در . متر با ھم مخابره کنند 500ساحه بيشتر از
. نظر ګرفته شوند
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طرح بندی آر ام آر مبنی بر مخابره با نيروی پايان يا ال پی آر )LPR (
Meter1
LPR
Meter7
Meter1
LPR
Meter4
Meter1
LPR
Meter5 Meter
1
LPR
Meter6
Meter1
LPR
Meter3
Meter1
LPR
Meter2
Meter1
LPR
Meter1
LPR
بنا نھادن مخابره
جمع آوری اطالعات
اشتباھات مذاکراتی
تغيير يافتن به ميتر بعدای
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نکات مھم درباره ای ام آر مبنی بر مخابره با نيروی پايان
متر است، نمايش کار واقعی ممکن بر اساس عوامل پوشيده 200بعد نظری آن بيشتر از . شده در بودجه ارتباطی متفاوت باشد
) يعنی ميترھای که روی پايه ھا نصب اند(خوانش ميترھای خارج از دسترس 1.
.2Daily meter readings in an Industrial area from a central location.
.3Monitoring in case of tamper prone sites.
.4Meter reading in hazardous/ un-safe area.
.5Virtually no running cost as no infrastructural services is hired.
.6Can be expanded to a walk-by system or in conjunction with a data-concentrator an automatic RMR system can be
setup.
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High power radio / City RMR
Meter1
LPR
Meter1
Meter1
LPR
Meter2
Meter1
LPR
Meter3
Meter1
LPR
Meter4
Data Concentrator
LPR Master
HPR
Cluster 1
Utility’s AMR station with HPR.
Cluster 2
Cluster 3
Cluster 4
Cluster 5
Cluster 6
Cluster 7
Moderate RF power due to tall antenna
No infrastructural cost
Suitable for a high revenue area
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Various Cellular Technologies• GSM -Global System for Mobile• CDMA -Code Division Multiple Access• GPRS -General Packet Radio Service• EDGE- Enhanced Data for GSM Evolution• W-CDMA- Wideband CDMA• UMTS- Universal Mobile Telecom System
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History
• 1946- Mobile concept appeared in the USA• 1970–BELL LABS introduced Cellular Principle• 1979 – AMPS system in US- Analog
– Advanced Mobile Phone service – US 800 MHz Band• 1980 – TACS & NMT systems-Analog
– Total Access Comm. System -UK 900 MHz Band– Nordic Mobile Telephone Service – Scandinavian
450/900 MHz Band • 1992 - GSM – Digital
– Global System for Mobile Communication – Europe 900 /1800 MHz
• 1992 – JDC – Japanese Digital Cellular -Digital• 1994 – DAMPS –Digital
– Digital AMPS - US 800 MHz Band , IS-54 , IS-136• 1994 – CDMA – Digital
– Code Division Multiple Access System – US 900 MHz , IS-95
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Communication Media: GSMGSM history• 1982 Groupe Special Mobile (GSM)• 1986 Field testing of different radio techniques.• 1987 TDMA chosen as access media• 1988 GSM transferred to newly formed ETSI
(European Telecommunication Standard Institute)• 1991 commercial launch of GSM• By 1993 GSM coverage exceeded the projections
made for 1995.
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Objectives set by the GSM groupe
• Spectral efficiency• International roaming• Low mobile and base station cost• Good subjective voice quality• Compatibility with other systems such as
ISDN• Ability to support new services
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GSM: Cellular structure
• Too many subscribers, limited frequency channels.
• Divide the available frequency channels in small regions called as cells.
• Reuse the frequency channels after 3 cell distance.
F1
F2
F4
F6
F5
F3
F1
F7
F8
Each Cell is a BTS
Each cell has a Cell Global Identity Number (CGI)
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The GSM Network
• The mobile station (MS)• Base Station Sub-system (BSS)• Network and Switching Sub-system
(NSS)• Operation and support Subsystem
(OSS)
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Mobile Network Architecture
PDN
Data Terminal
HLR/VLR
MSCBSC
OMC(Operation & Maintenance
Center)
Operation Terminal
BTS
HandsetA
X.25
A-bisSS7
Network sub-systemPSTN
Radiosub-system
Mobilestation
UM
SIMcard
MSC
VLR
PSTN
BSS
ISDN
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Architecture of GSM Network
Ludhiana
Amritsar
Chandigarh
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GSM: The mobile stationMobile station consists of two main elements:
1. Mobile equipment or terminal (for data)
2. The subscriber Identity Module (SIM)
SIM is ISO compliant removable smart card which identifies the terminal
SIM contains International Mobile Subscriber Identity (IMSI). This is a unique number which is different from the telephone number.
SIM is responsible for operation of mobile equipment, location management, authentication and ciphering.
All the calls are routed through SIM, not the mobile equipment.
The concept of SIM was silently resisted by mobile equipment manufacturers. The GSM groupe did in favor of consumer by adapting.
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Network and Switching Subsystem (NSS)
• NSS is the main component of the mobile GSM network.– Switching, mobility management, interconnection to other
networks, system control.• Components
– Mobile Service Switching Service (MSC)• Controls all connections via a separate network to/ from a mobile
terminal within the domain of MSC, several BSC can belong to a MSC.
– Databases (scalable, high capacity, low delay)• Home Location Register (HLR)
– Central master database containing user data, permanent and semi-permanent data of all subscribers assigned to the HLR.
• Visitor Location Register (VLR)– Local database for a subset of user data, including data about all user
currently in the domain of VLR
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Mobile service switching center (MSC)MSC provides switching functions of the network.
HLR : Home Location register which contains subscribers fixed information
VLR: Visitor Location Register: Information on all the subscribers in the service area (including the roaming visitor)
AUC: Authentication Center: Used to verify users identity, authentication and encryption function.
IWU
EIR: Equipment Identity Register: Stores the IMEI. Stolen mobiles are traced by this.
IWU: Inter Working Unit: Provides interface to various networks of data communication.
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GSM: Radio Transmission Aspect.• Spectrum allocation
• 890 to 915 MHz for up-link (Mobile station to base station)
• 935 to 960 MHz for downlink (Base station to mobile station)
• Multiple access:• 124 carriers are spaced
200 KHz. • TDMA divides time on
each carrier frequency into burst period (0.577ms).
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When a mobile station is switched onCatches the pilot, seeks service information. Informs its IMSI and location to MSC.
Authentication is carried out by SIM and AuC. EIR is also checked if requested.
The subscription details and location is update in the VLR from HLR in the MSC.
In case of “roaming subscriber” the subscription details are requested from “HOME MSC” and based on remote AuC, the services are released. Both Home MSC and local MSC gets synchronized and VLR is updated.
The user gets the “signal bar” and service area Name on his device.
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Multiple access techniques: Serving many users with limited resources (channels)
Multiple access Method
MS & BS share knowledge about
FDMA Frequency
TDMA Time
CDMA PN code
P
Frequency
FDMA
Frequency
P
TimeTime
TDMA
P
Frequency
Time
CDMA
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GSM Uses combination of TDMA and FDMA: How long are you connected?
T0 T1 T2 T3 T4 T 7T6T5
4.615 ms
T0
.577 m S
T0 T1 T2 T3 T4 T 7T6T5
4.615 ms
T0
.577 m S
A mobile station receives data for “.577 m S” in every 4.615 mS. Hence each frequency channel can cater 8 calls. There are many channels in a “cell”. Hence the number of simultaneous calls that can be handled in a cell are in multiples of 8.
A background noise is transmitted to the Mobile station which is played during blanking period. The blank is never noticed by human ear / brain.
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GSM: Roaming, Location Registration & handover
BTS 1
BTS 2
Base Station Controller (one in a city)
MSC
VLRMobile station sends signal strength of 12 surrounding cells periodically.
MSC, based on the relative signal strength and traffic conditions decides on “Handing over the call to neighboring cell.
MSC, current BTS and new BTS along with the MS are involved in successful handover.
Types of handover
1. Handover of channels in the same cell
2. Handover of cells controlled by the same BSC
3. Handover of cells belonging to the same MSC but controlled by different BSC
4. Handover of cells controlled by different MSC’s.
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GSM Data communication properties
• Native Circuit Switch operation• Uplink and downlink channels allocated for a user for
entire call.• Busy user uses only one direction of link so 50% of
the resources are wasted.• Connection establishment time:20-25 seconds• Capacity: 9.6 kBPS• Connections: to any modem service in PSTN.• Billing is based on “time” and not the amount of data.• GPRS is deployed for packet switch data.
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GSM Based RMR: Media Interface device• GSM being “digital” does not
needs modem.• MID in GSM is called as GSM
terminal.• GSM data needs individual
subscription (SIM).• GSM terminal has elaborate
“AT” command structure to support data.
• GSM Terminal is an emulated modem with the real modem being IWU.
• Liaison with service provider is necessary.
GSM Termina
l
MSC
IWUModem
PSTN
In Station Modem
Digital Communication
Analog Communication
Digital Communication
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Typical GSM based RMR installation in India
Electronic Meter with “RS232” communication port.
GSM terminal with integral Wide range power supply, Antenna and “SIM” card holder.
Meter box
Please note that the Antenna Should be outside/ close to the glass window so that radio signal can pass.
& it works!!!! To earn back its cost
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Benefits of GSM Based RMR• Instant installation and its mobility.• Secure, can not be vandalized by cutting wires etc.• Callers other than authorized can be barred.• In-built error correction.• CUG: GSM service providers are prepared to offer close
user group for cheap calls and secrecy.• Facility to send “SMS” in case of tamper, power up-down or
any other abnormal condition which can have a pulse output,
• Potential application of GSM based RMR is monitoring “seasonal consumer” who under quote their “demand” for year round benefit.
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GPRS – General Packet Radio Service• Based on existing GSM infrastructure
• Better than GSM in terms of data transfer rates
• Provides more reliability of data transfer – more meters read per day.
• GSM is a CSD method where as GPRS is Packet based technology
• More similar to Internet access and its structure
• Payload is charged.
• Communication over TCP/IP is secure.
• Simultaneous readings of large no. of meters. Remember - Connection less
• Flexible and expandable system
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GPRS based RMR System
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Understanding CDMA based data transferCDMA = Code Division Multiple Access
A B
The base station transmits coded data for all receivers at the same frequency and similarly all receivers send their information with individual code at the same frequency.
Negotiating a call, the Base station and target receiver agrees on a special code.
Information pertaining to the target receiver is encoded using special code called as PN code. (Pseudo Random code)
Data pertaining to base station and that of the target meter is decoded by using the respective PN code.
PIN codes may repeat once during a continuous communication of 32 days!
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How do we get connected to the internet?
Telephone exchange
Dial the service provider (1772)
ISP has a stock of IP-Address
1. A.B.C.D
2. 172.28.126.110
3. 172.109.12.120
4. nnn.nnn.nnn.nnn You are provided with one of the available IP address, e.g. 172.109.12.120
All your queries are forwarded to the selected websites with your IP address 172.109.12.120. You get a reply on 172.109.12.120.
In the next attempt to access internet , you may get a different IP address eg. 172.28.126.110.
The random IP address is called as DYNAMIC or TEMPORARY IP address
You can get permanent IP address if your usage is for 24 hrs x 7 x 30. Else, permanent IP will be expensive.
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TCP/IP
A B
D CRouter matches the address with its
routing table.
1. Destination Address?
2. Part of the address Network ID?
3. Default hop?
A.B.C.D
Information is broken into small packets.
Each packet is packed in an Envelope with packet number and address.
Packets are delivered irrespective of the packet No/ sequence
Original page is formed at the receiver.
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Lets Summaries, internet access
• Internet uses packet switching connection.• Data transfer over internet needs TCP/IP protocol. Your PC
does the job of breaking the page to packets and building the page from packets.
• Each packet has the sender, receiver address, the packet serial number and data integrity information.
• Remember, your PC connects to the web-site, not the web-site get connected to your PC. Why? Recall: Websites has fixed IP whereas your dialup connection has a Dynamic IP.
• Whereas in circuit switch system, the end-to-end circuit is prior established, whatever you send from end-1, reaches end-2 in nearly real time.
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Data transfer over CDMAPoint-to-point data communication is NOT allowed.
Only internet surfing is allowed.
CDMA TERMINAL
TRANSPARENTPC with TCP/IP
stack
Serial to TCP/IP Converter
WWW
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CDMA based Remote Meter Reading
Serial to TCP/IP
Converter
WWW. meterdata.com
A permanent IP Number.
Program the black box the address of meterdata.com
Temporary IP Address.
Meter does not have a IP address. Hence, the UTILITY can not reach a meter like telephone based RMR
The meter can reach the meter reading station because MS has a permanent IP address.
Besides the CDMA terminal, you also need the serial-TCP/IP converter, a permanent IP for reading station. The meter is programmed to send its reading or SMS the meter to do so.
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Benefits of CDMA based meter reading
• Payload is charged.• Communication over TCP/IP is secure.• The serial to IP converter can be used as
“store-and-forward” device to improve the communication speed.
• Simultaneous readings of 10’s of meters. Remember.. Connection less.
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Evolution Path
• 2nd GenerationGSM -9.6 Kbps (data rate)
• 2.5 Generation (Future of GSM)HSCSD (High Speed Circuit Switched Data)
Data rate : 76.8 Kbps (9.6 x 8 kbps)GPRS (General Packet Radio service)
Data rate: 14.4 - 115.2 KbpsEDGE (Enhanced Data for GSM Evolution)
Data rate: 547.2 Kbps (max)
• 3rd GenerationWCDMA (Wide band CDMA)
Data rate : 0.348 – 2.0 Mbps
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The digital interface
• Communication in electronic meters have the following characteristics:
• Rate of transmission (baud rate)• Half-duplex / full duplex• Type of digital interface.
Digital Interface:
• Optical port.• RS232 Physical port (internal isolated)• RS485 Physical port (Internal isolated)
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The RS232 interface
• Industry standard and is easily available on PC’s and MRI.
• Available in special meters for electrical connectivity to modems / PC’s
• A group of meters can be connected reducing the MID count.
• Suitable for sites having cable run less than 50’.
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Polling: Multiplexing using equipment identification.
• Objective: To connect several meters to a single DCU e.g. PC or modem.
Meter 1
Meter 4 Meter 5 Meter 6
Meter 3Meter 2
?
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Keywords: Global disable, specific enable.
Meter 1
Meter 4 Meter 5 Meter 6
Meter 3Meter 2
Line Driver
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Online Systems
• Data on real time basis • Different from On-demand Systems (AMR/
RMR)• Communication media selection depends
on application & objective of the system to be deployed
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MSETCL System Architecture
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HZL System Architecture
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Thank you for your attention. Any questions?
Rajesh.Nimare@securemeters.com