SlideShare a Scribd company logo
1 of 13
Download to read offline
GSM: Handover
www.rsmangrulkar.com
January 24, 2018
www.rsmangrulkar.com GSM: Handover
Handovers
www.rsmangrulkar.com GSM: Handover
Handovers or Handoffs
Why Handovers Required
For Seamless mobility / connectivity , to prevent call drop.
When mobile node move away from cell centre(tower/ BTS)
towards cell edge, signal level dropped. This can be
continuously transferred through Measurement Reports to
BTS.
One of the key elements of a mobile phone or cellular
telecommunications system, is that the system is split
into many small cells to provide good frequency re-use
and coverage.
However as the mobile moves out of one cell to another it
must be possible to retain the connection. Passing of
control from one cell to another cell . The process by
which this occurs is known as handover or handoff.
Its a critical process and if performed incorrectly handoverwww.rsmangrulkar.com GSM: Handover
Types of Handover
Hard Handover : Used in GSM
Break before Make
Soft Handover : Used in 3G
Make before Make
www.rsmangrulkar.com GSM: Handover
Factors Affecting Handover
Transmitted power: as we know that the transmission
power is different for different cells, the handoff threshold
or the power margin varies from cell to cell.
Received power: the received power mostly depends on
the Line of Sight (LoS) path between the user and the
BS.
Area and shape of the cell: Apart from the power levels,
the cell structure also a plays an important role in the
handoff process.
Mobility of users: The number of mobile users entering or
going out of a particular cell, also fixes the handoff
strategy of a cell.
www.rsmangrulkar.com GSM: Handover
Types of Handover in GSM
www.rsmangrulkar.com GSM: Handover
Types of Handover
Intra-BTS handover This form of GSM handover occurs if it
is required to change the frequency or slot being used by a
mobile because of interference, or other reasons. In this form
of GSM handover, the mobile remains attached to the same
base station transceiver, but changes the channel or slot.
www.rsmangrulkar.com GSM: Handover
Intra-BTS handover
Figure 3: Types of Handover
www.rsmangrulkar.com GSM: Handover
Inter-BTS Intra BSC handover This for of GSM handover
or GSM handoff occurs when the mobile moves out of the
coverage area of one BTS but into another controlled by the
same BSC. In this instance the BSC is able to perform the
handover and it assigns a new channel and slot to the mobile,
before releasing the old BTS from communicating with the
mobile.
Inter-BSC handover When the mobile moves out of the
range of cells controlled by one BSC, a more involved form of
handover has to be performed, handing over not only from one
BTS to another but one BSC to another. For this the
handover is controlled by the MSC.
www.rsmangrulkar.com GSM: Handover
Inter-MSC handover This form of handover occurs when
changing between networks. The two MSCs involved negotiate
to control the handover.
www.rsmangrulkar.com GSM: Handover
Handoffs In Different Generations
In 1G analog cellular systems, the signal strength measurements were made by the BS and in turn
supervised by the MSC. The handoffs in this generation can be termed as Network Controlled Hand-Off
(NCHO). The approximate time needed to make a handoff successful was about 5-10 s.
In 2nd generation, which started using the digital technology, handoff decisions were mobile assisted and
therefore it is called Mobile Assisted Hand-Off (MAHO). In MAHO, the mobile center measures the power
changes received from nearby base stations and notifies the two BS. Delay in handoff was reduced to 1-5 s.
In the current 3G systems, the MS measures the power from adjacent BS and automatically upgrades the
channels to its nearer BS. Hence this can be termed as Mobile Controlled Hand-Off (MCHO).
Mobility of users: The number of mobile users entering or going out of a particular cell, also fixes the
handoff strategy of a cell.
www.rsmangrulkar.com GSM: Handover
All these types of handoffs are usually termed as hard handoff
as there is a shift in the channels involved. There is also
another kind of handoff, called soft handoff
www.rsmangrulkar.com GSM: Handover
Handoff in CDMA: In spread spectrum cellular systems, the
mobiles share the same channels in every cell. The MSC
evaluates the signal strengths received from different BS for a
single user and then shifts the user from one BS to the other
without actually changing the channel. These types of
handoffs are called as soft handoff as there is no change in the
channel.
www.rsmangrulkar.com GSM: Handover

More Related Content

What's hot (20)

Handover
HandoverHandover
Handover
 
Wireless Local Loop
Wireless Local LoopWireless Local Loop
Wireless Local Loop
 
Cellular network
Cellular networkCellular network
Cellular network
 
Geographic Routing in WSN
Geographic Routing in WSNGeographic Routing in WSN
Geographic Routing in WSN
 
Demand Assigned Multiple Access
Demand Assigned Multiple AccessDemand Assigned Multiple Access
Demand Assigned Multiple Access
 
Gsm architecture
Gsm architectureGsm architecture
Gsm architecture
 
UMTS, Introduction.
UMTS, Introduction.UMTS, Introduction.
UMTS, Introduction.
 
Mobile Network Layer
Mobile Network LayerMobile Network Layer
Mobile Network Layer
 
Paging and Location Update
Paging and Location UpdatePaging and Location Update
Paging and Location Update
 
ELEMENTS OF CELLULAR RADIO SYSTEM DESIGN
ELEMENTS OF CELLULAR RADIO SYSTEM DESIGNELEMENTS OF CELLULAR RADIO SYSTEM DESIGN
ELEMENTS OF CELLULAR RADIO SYSTEM DESIGN
 
Handover
HandoverHandover
Handover
 
Mobile Originated Call Process in Simple Words
Mobile Originated Call Process in Simple WordsMobile Originated Call Process in Simple Words
Mobile Originated Call Process in Simple Words
 
Mobility Management
Mobility ManagementMobility Management
Mobility Management
 
WCDMA
WCDMAWCDMA
WCDMA
 
Presentation on CDMA
Presentation on CDMAPresentation on CDMA
Presentation on CDMA
 
GSM - Addresses and Identifiers
GSM - Addresses and IdentifiersGSM - Addresses and Identifiers
GSM - Addresses and Identifiers
 
Wcdma channels
Wcdma channels Wcdma channels
Wcdma channels
 
GSM Location area update
GSM Location area updateGSM Location area update
GSM Location area update
 
Umts system architecture
Umts system architectureUmts system architecture
Umts system architecture
 
Cdma2000
Cdma2000Cdma2000
Cdma2000
 

Similar to GSM: Handovers

WCDMA Principles
WCDMA PrinciplesWCDMA Principles
WCDMA PrinciplesAli Ibrahim
 
Handover between wcdma_and_gsm
Handover between wcdma_and_gsmHandover between wcdma_and_gsm
Handover between wcdma_and_gsmHatim100
 
Bt0086, mobile computing
Bt0086, mobile computingBt0086, mobile computing
Bt0086, mobile computingsmumbahelp
 
Wap based seamless roaming in urban environment with wise handoff technique
Wap based seamless roaming in urban environment with wise handoff techniqueWap based seamless roaming in urban environment with wise handoff technique
Wap based seamless roaming in urban environment with wise handoff techniqueijujournal
 
A project report_at_cell_phone_detector - copy
A project report_at_cell_phone_detector - copyA project report_at_cell_phone_detector - copy
A project report_at_cell_phone_detector - copyPranoosh T
 
Comparison between gsm & cdma najmul hoque munshi
Comparison between gsm & cdma najmul hoque munshiComparison between gsm & cdma najmul hoque munshi
Comparison between gsm & cdma najmul hoque munshiNajmulHoqueMunshi
 
An electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio networkAn electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio networkeSAT Publishing House
 
An electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio networkAn electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio networkeSAT Journals
 
presentation on gsm architecture and fixed assignment
presentation on gsm architecture and fixed assignmentpresentation on gsm architecture and fixed assignment
presentation on gsm architecture and fixed assignmentFabiha Ain
 
Mobile communication - GSM/CDMA/WIMAX Technologies
Mobile communication - GSM/CDMA/WIMAX TechnologiesMobile communication - GSM/CDMA/WIMAX Technologies
Mobile communication - GSM/CDMA/WIMAX TechnologiesAman Abhishek
 
Auto rain gauge radio module
Auto rain gauge radio moduleAuto rain gauge radio module
Auto rain gauge radio moduleUjwal Saha
 
2g,3g,4g, technology Dialog axiata
2g,3g,4g, technology Dialog axiata2g,3g,4g, technology Dialog axiata
2g,3g,4g, technology Dialog axiataHasitha Neelaka
 
Gsm energy meter
Gsm energy meterGsm energy meter
Gsm energy meterikm104
 

Similar to GSM: Handovers (20)

B04502005008
B04502005008B04502005008
B04502005008
 
Handover management
Handover managementHandover management
Handover management
 
WCDMA Principles
WCDMA PrinciplesWCDMA Principles
WCDMA Principles
 
Aj03402040209
Aj03402040209Aj03402040209
Aj03402040209
 
WCDMA_new
WCDMA_newWCDMA_new
WCDMA_new
 
Handover between wcdma_and_gsm
Handover between wcdma_and_gsmHandover between wcdma_and_gsm
Handover between wcdma_and_gsm
 
Mobile Technology
Mobile TechnologyMobile Technology
Mobile Technology
 
Ch5
Ch5Ch5
Ch5
 
Bt0086, mobile computing
Bt0086, mobile computingBt0086, mobile computing
Bt0086, mobile computing
 
Gsm
GsmGsm
Gsm
 
Wap based seamless roaming in urban environment with wise handoff technique
Wap based seamless roaming in urban environment with wise handoff techniqueWap based seamless roaming in urban environment with wise handoff technique
Wap based seamless roaming in urban environment with wise handoff technique
 
A project report_at_cell_phone_detector - copy
A project report_at_cell_phone_detector - copyA project report_at_cell_phone_detector - copy
A project report_at_cell_phone_detector - copy
 
Comparison between gsm & cdma najmul hoque munshi
Comparison between gsm & cdma najmul hoque munshiComparison between gsm & cdma najmul hoque munshi
Comparison between gsm & cdma najmul hoque munshi
 
An electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio networkAn electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio network
 
An electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio networkAn electric circuits' remote switching system based on gsm radio network
An electric circuits' remote switching system based on gsm radio network
 
presentation on gsm architecture and fixed assignment
presentation on gsm architecture and fixed assignmentpresentation on gsm architecture and fixed assignment
presentation on gsm architecture and fixed assignment
 
Mobile communication - GSM/CDMA/WIMAX Technologies
Mobile communication - GSM/CDMA/WIMAX TechnologiesMobile communication - GSM/CDMA/WIMAX Technologies
Mobile communication - GSM/CDMA/WIMAX Technologies
 
Auto rain gauge radio module
Auto rain gauge radio moduleAuto rain gauge radio module
Auto rain gauge radio module
 
2g,3g,4g, technology Dialog axiata
2g,3g,4g, technology Dialog axiata2g,3g,4g, technology Dialog axiata
2g,3g,4g, technology Dialog axiata
 
Gsm energy meter
Gsm energy meterGsm energy meter
Gsm energy meter
 

More from Dr. Ramchandra Mangrulkar

Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)
Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)
Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)Dr. Ramchandra Mangrulkar
 
Lecture #32: Digital Forensics : Evidence Handling, Validation and Reporting
Lecture #32: Digital Forensics : Evidence Handling, Validation and ReportingLecture #32: Digital Forensics : Evidence Handling, Validation and Reporting
Lecture #32: Digital Forensics : Evidence Handling, Validation and ReportingDr. Ramchandra Mangrulkar
 
Lecture #24 : Cross Site Request Forgery (CSRF)
Lecture #24 : Cross Site Request Forgery (CSRF)Lecture #24 : Cross Site Request Forgery (CSRF)
Lecture #24 : Cross Site Request Forgery (CSRF)Dr. Ramchandra Mangrulkar
 
Lecture #18 - #20: Web Browser and Web Application Security
Lecture #18 - #20: Web Browser and Web Application SecurityLecture #18 - #20: Web Browser and Web Application Security
Lecture #18 - #20: Web Browser and Web Application SecurityDr. Ramchandra Mangrulkar
 
Lecture #15: Buffer Overflow Attack (Non Malicious Attack)
Lecture #15: Buffer Overflow Attack (Non Malicious Attack)Lecture #15: Buffer Overflow Attack (Non Malicious Attack)
Lecture #15: Buffer Overflow Attack (Non Malicious Attack)Dr. Ramchandra Mangrulkar
 
Lecture # 14: Salami and Linearization Attacks
Lecture # 14: Salami and Linearization Attacks Lecture # 14: Salami and Linearization Attacks
Lecture # 14: Salami and Linearization Attacks Dr. Ramchandra Mangrulkar
 
Lecture #12,#13 : Program and OS Security -Part I
Lecture #12,#13 : Program and OS Security -Part ILecture #12,#13 : Program and OS Security -Part I
Lecture #12,#13 : Program and OS Security -Part IDr. Ramchandra Mangrulkar
 
Lecture #9 : Single Sign on and Federation Identity Management
Lecture #9 :  Single Sign on and Federation Identity ManagementLecture #9 :  Single Sign on and Federation Identity Management
Lecture #9 : Single Sign on and Federation Identity ManagementDr. Ramchandra Mangrulkar
 
Lecture #8: Clark-Wilson & Chinese Wall Model for Multilevel Security
Lecture #8: Clark-Wilson & Chinese Wall Model for Multilevel SecurityLecture #8: Clark-Wilson & Chinese Wall Model for Multilevel Security
Lecture #8: Clark-Wilson & Chinese Wall Model for Multilevel SecurityDr. Ramchandra Mangrulkar
 

More from Dr. Ramchandra Mangrulkar (20)

Blockchain#2.pdf
Blockchain#2.pdfBlockchain#2.pdf
Blockchain#2.pdf
 
Blockchain#1.pdf
Blockchain#1.pdfBlockchain#1.pdf
Blockchain#1.pdf
 
Blockchain#3.pdf
Blockchain#3.pdfBlockchain#3.pdf
Blockchain#3.pdf
 
Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)
Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)
Manuscript Preparation using Latex: A Cloud Based Approach(Overleaf)
 
Lecture #32: Forensic Duplication
Lecture #32: Forensic DuplicationLecture #32: Forensic Duplication
Lecture #32: Forensic Duplication
 
Lecture #32: Digital Forensics : Evidence Handling, Validation and Reporting
Lecture #32: Digital Forensics : Evidence Handling, Validation and ReportingLecture #32: Digital Forensics : Evidence Handling, Validation and Reporting
Lecture #32: Digital Forensics : Evidence Handling, Validation and Reporting
 
LEcture #28-#30
LEcture #28-#30LEcture #28-#30
LEcture #28-#30
 
Lecture #31 : Windows Forensics
Lecture #31 : Windows ForensicsLecture #31 : Windows Forensics
Lecture #31 : Windows Forensics
 
Lecture #25 : Oauth 2.0
Lecture #25 : Oauth 2.0Lecture #25 : Oauth 2.0
Lecture #25 : Oauth 2.0
 
Lecture #24 : Cross Site Request Forgery (CSRF)
Lecture #24 : Cross Site Request Forgery (CSRF)Lecture #24 : Cross Site Request Forgery (CSRF)
Lecture #24 : Cross Site Request Forgery (CSRF)
 
Lecture #22: Web Privacy & Security Breach
Lecture #22: Web Privacy & Security BreachLecture #22: Web Privacy & Security Breach
Lecture #22: Web Privacy & Security Breach
 
Lecture #22 : Web Privacy & Security Breach
Lecture #22 : Web Privacy & Security BreachLecture #22 : Web Privacy & Security Breach
Lecture #22 : Web Privacy & Security Breach
 
Lecture #21: HTTPS , SSL & TLS
Lecture #21: HTTPS , SSL & TLSLecture #21: HTTPS , SSL & TLS
Lecture #21: HTTPS , SSL & TLS
 
Lecture #18 - #20: Web Browser and Web Application Security
Lecture #18 - #20: Web Browser and Web Application SecurityLecture #18 - #20: Web Browser and Web Application Security
Lecture #18 - #20: Web Browser and Web Application Security
 
Lecture #15: Buffer Overflow Attack (Non Malicious Attack)
Lecture #15: Buffer Overflow Attack (Non Malicious Attack)Lecture #15: Buffer Overflow Attack (Non Malicious Attack)
Lecture #15: Buffer Overflow Attack (Non Malicious Attack)
 
Lecture # 14: Salami and Linearization Attacks
Lecture # 14: Salami and Linearization Attacks Lecture # 14: Salami and Linearization Attacks
Lecture # 14: Salami and Linearization Attacks
 
Lecture #12,#13 : Program and OS Security -Part I
Lecture #12,#13 : Program and OS Security -Part ILecture #12,#13 : Program and OS Security -Part I
Lecture #12,#13 : Program and OS Security -Part I
 
Lecture #9 : Single Sign on and Federation Identity Management
Lecture #9 :  Single Sign on and Federation Identity ManagementLecture #9 :  Single Sign on and Federation Identity Management
Lecture #9 : Single Sign on and Federation Identity Management
 
Lecture #8: Clark-Wilson & Chinese Wall Model for Multilevel Security
Lecture #8: Clark-Wilson & Chinese Wall Model for Multilevel SecurityLecture #8: Clark-Wilson & Chinese Wall Model for Multilevel Security
Lecture #8: Clark-Wilson & Chinese Wall Model for Multilevel Security
 
Lecture #6: Multilevel Security Models
Lecture #6: Multilevel Security ModelsLecture #6: Multilevel Security Models
Lecture #6: Multilevel Security Models
 

Recently uploaded

Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...amrabdallah9
 
Renewable Energy & Entrepreneurship Workshop_21Feb2024.pdf
Renewable Energy & Entrepreneurship Workshop_21Feb2024.pdfRenewable Energy & Entrepreneurship Workshop_21Feb2024.pdf
Renewable Energy & Entrepreneurship Workshop_21Feb2024.pdfodunowoeminence2019
 
IT3401-WEB ESSENTIALS PRESENTATIONS.pptx
IT3401-WEB ESSENTIALS PRESENTATIONS.pptxIT3401-WEB ESSENTIALS PRESENTATIONS.pptx
IT3401-WEB ESSENTIALS PRESENTATIONS.pptxSAJITHABANUS
 
The relationship between iot and communication technology
The relationship between iot and communication technologyThe relationship between iot and communication technology
The relationship between iot and communication technologyabdulkadirmukarram03
 
nvidia AI-gtc 2024 partial slide deck.pptx
nvidia AI-gtc 2024 partial slide deck.pptxnvidia AI-gtc 2024 partial slide deck.pptx
nvidia AI-gtc 2024 partial slide deck.pptxjasonsedano2
 
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...soginsider
 
specification estimation and valuation of a building
specification estimation and valuation of a buildingspecification estimation and valuation of a building
specification estimation and valuation of a buildingswethasekhar5
 
CSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptxCSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptxssusera0771e
 
cme397 surface engineering unit 5 part A questions and answers
cme397 surface engineering unit 5 part A questions and answerscme397 surface engineering unit 5 part A questions and answers
cme397 surface engineering unit 5 part A questions and answerskarthi keyan
 
SUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docx
SUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docxSUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docx
SUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docxNaveenVerma126
 
Phase noise transfer functions.pptx
Phase noise transfer      functions.pptxPhase noise transfer      functions.pptx
Phase noise transfer functions.pptxSaiGouthamSunkara
 
دليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide Laboratory
دليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide Laboratoryدليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide Laboratory
دليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide LaboratoryBahzad5
 
Modelling Guide for Timber Structures - FPInnovations
Modelling Guide for Timber Structures - FPInnovationsModelling Guide for Timber Structures - FPInnovations
Modelling Guide for Timber Structures - FPInnovationsYusuf Yıldız
 
Introduction to Machine Learning Unit-3 for II MECH
Introduction to Machine Learning Unit-3 for II MECHIntroduction to Machine Learning Unit-3 for II MECH
Introduction to Machine Learning Unit-3 for II MECHC Sai Kiran
 
ChatGPT-and-Generative-AI-Landscape Working of generative ai search
ChatGPT-and-Generative-AI-Landscape Working of generative ai searchChatGPT-and-Generative-AI-Landscape Working of generative ai search
ChatGPT-and-Generative-AI-Landscape Working of generative ai searchrohitcse52
 
Oracle_PLSQL_basic_tutorial_with_workon_Exercises.ppt
Oracle_PLSQL_basic_tutorial_with_workon_Exercises.pptOracle_PLSQL_basic_tutorial_with_workon_Exercises.ppt
Oracle_PLSQL_basic_tutorial_with_workon_Exercises.pptDheerajKashnyal
 

Recently uploaded (20)

Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
Strategies of Urban Morphologyfor Improving Outdoor Thermal Comfort and Susta...
 
Renewable Energy & Entrepreneurship Workshop_21Feb2024.pdf
Renewable Energy & Entrepreneurship Workshop_21Feb2024.pdfRenewable Energy & Entrepreneurship Workshop_21Feb2024.pdf
Renewable Energy & Entrepreneurship Workshop_21Feb2024.pdf
 
IT3401-WEB ESSENTIALS PRESENTATIONS.pptx
IT3401-WEB ESSENTIALS PRESENTATIONS.pptxIT3401-WEB ESSENTIALS PRESENTATIONS.pptx
IT3401-WEB ESSENTIALS PRESENTATIONS.pptx
 
The relationship between iot and communication technology
The relationship between iot and communication technologyThe relationship between iot and communication technology
The relationship between iot and communication technology
 
nvidia AI-gtc 2024 partial slide deck.pptx
nvidia AI-gtc 2024 partial slide deck.pptxnvidia AI-gtc 2024 partial slide deck.pptx
nvidia AI-gtc 2024 partial slide deck.pptx
 
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...Transforming Process Safety Management: Challenges, Benefits, and Transition ...
Transforming Process Safety Management: Challenges, Benefits, and Transition ...
 
計劃趕得上變化
計劃趕得上變化計劃趕得上變化
計劃趕得上變化
 
Lecture 2 .pdf
Lecture 2                           .pdfLecture 2                           .pdf
Lecture 2 .pdf
 
specification estimation and valuation of a building
specification estimation and valuation of a buildingspecification estimation and valuation of a building
specification estimation and valuation of a building
 
CSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptxCSR Managerial Round Questions and answers.pptx
CSR Managerial Round Questions and answers.pptx
 
cme397 surface engineering unit 5 part A questions and answers
cme397 surface engineering unit 5 part A questions and answerscme397 surface engineering unit 5 part A questions and answers
cme397 surface engineering unit 5 part A questions and answers
 
SUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docx
SUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docxSUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docx
SUMMER TRAINING REPORT ON BUILDING CONSTRUCTION.docx
 
Lecture 4 .pdf
Lecture 4                              .pdfLecture 4                              .pdf
Lecture 4 .pdf
 
Phase noise transfer functions.pptx
Phase noise transfer      functions.pptxPhase noise transfer      functions.pptx
Phase noise transfer functions.pptx
 
دليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide Laboratory
دليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide Laboratoryدليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide Laboratory
دليل تجارب الاسفلت المختبرية - Asphalt Experiments Guide Laboratory
 
Modelling Guide for Timber Structures - FPInnovations
Modelling Guide for Timber Structures - FPInnovationsModelling Guide for Timber Structures - FPInnovations
Modelling Guide for Timber Structures - FPInnovations
 
Introduction to Machine Learning Unit-3 for II MECH
Introduction to Machine Learning Unit-3 for II MECHIntroduction to Machine Learning Unit-3 for II MECH
Introduction to Machine Learning Unit-3 for II MECH
 
ChatGPT-and-Generative-AI-Landscape Working of generative ai search
ChatGPT-and-Generative-AI-Landscape Working of generative ai searchChatGPT-and-Generative-AI-Landscape Working of generative ai search
ChatGPT-and-Generative-AI-Landscape Working of generative ai search
 
Oracle_PLSQL_basic_tutorial_with_workon_Exercises.ppt
Oracle_PLSQL_basic_tutorial_with_workon_Exercises.pptOracle_PLSQL_basic_tutorial_with_workon_Exercises.ppt
Oracle_PLSQL_basic_tutorial_with_workon_Exercises.ppt
 
Lecture 2 .pptx
Lecture 2                            .pptxLecture 2                            .pptx
Lecture 2 .pptx
 

GSM: Handovers

  • 1. GSM: Handover www.rsmangrulkar.com January 24, 2018 www.rsmangrulkar.com GSM: Handover
  • 3. Handovers or Handoffs Why Handovers Required For Seamless mobility / connectivity , to prevent call drop. When mobile node move away from cell centre(tower/ BTS) towards cell edge, signal level dropped. This can be continuously transferred through Measurement Reports to BTS. One of the key elements of a mobile phone or cellular telecommunications system, is that the system is split into many small cells to provide good frequency re-use and coverage. However as the mobile moves out of one cell to another it must be possible to retain the connection. Passing of control from one cell to another cell . The process by which this occurs is known as handover or handoff. Its a critical process and if performed incorrectly handoverwww.rsmangrulkar.com GSM: Handover
  • 4. Types of Handover Hard Handover : Used in GSM Break before Make Soft Handover : Used in 3G Make before Make www.rsmangrulkar.com GSM: Handover
  • 5. Factors Affecting Handover Transmitted power: as we know that the transmission power is different for different cells, the handoff threshold or the power margin varies from cell to cell. Received power: the received power mostly depends on the Line of Sight (LoS) path between the user and the BS. Area and shape of the cell: Apart from the power levels, the cell structure also a plays an important role in the handoff process. Mobility of users: The number of mobile users entering or going out of a particular cell, also fixes the handoff strategy of a cell. www.rsmangrulkar.com GSM: Handover
  • 6. Types of Handover in GSM www.rsmangrulkar.com GSM: Handover
  • 7. Types of Handover Intra-BTS handover This form of GSM handover occurs if it is required to change the frequency or slot being used by a mobile because of interference, or other reasons. In this form of GSM handover, the mobile remains attached to the same base station transceiver, but changes the channel or slot. www.rsmangrulkar.com GSM: Handover
  • 8. Intra-BTS handover Figure 3: Types of Handover www.rsmangrulkar.com GSM: Handover
  • 9. Inter-BTS Intra BSC handover This for of GSM handover or GSM handoff occurs when the mobile moves out of the coverage area of one BTS but into another controlled by the same BSC. In this instance the BSC is able to perform the handover and it assigns a new channel and slot to the mobile, before releasing the old BTS from communicating with the mobile. Inter-BSC handover When the mobile moves out of the range of cells controlled by one BSC, a more involved form of handover has to be performed, handing over not only from one BTS to another but one BSC to another. For this the handover is controlled by the MSC. www.rsmangrulkar.com GSM: Handover
  • 10. Inter-MSC handover This form of handover occurs when changing between networks. The two MSCs involved negotiate to control the handover. www.rsmangrulkar.com GSM: Handover
  • 11. Handoffs In Different Generations In 1G analog cellular systems, the signal strength measurements were made by the BS and in turn supervised by the MSC. The handoffs in this generation can be termed as Network Controlled Hand-Off (NCHO). The approximate time needed to make a handoff successful was about 5-10 s. In 2nd generation, which started using the digital technology, handoff decisions were mobile assisted and therefore it is called Mobile Assisted Hand-Off (MAHO). In MAHO, the mobile center measures the power changes received from nearby base stations and notifies the two BS. Delay in handoff was reduced to 1-5 s. In the current 3G systems, the MS measures the power from adjacent BS and automatically upgrades the channels to its nearer BS. Hence this can be termed as Mobile Controlled Hand-Off (MCHO). Mobility of users: The number of mobile users entering or going out of a particular cell, also fixes the handoff strategy of a cell. www.rsmangrulkar.com GSM: Handover
  • 12. All these types of handoffs are usually termed as hard handoff as there is a shift in the channels involved. There is also another kind of handoff, called soft handoff www.rsmangrulkar.com GSM: Handover
  • 13. Handoff in CDMA: In spread spectrum cellular systems, the mobiles share the same channels in every cell. The MSC evaluates the signal strengths received from different BS for a single user and then shifts the user from one BS to the other without actually changing the channel. These types of handoffs are called as soft handoff as there is no change in the channel. www.rsmangrulkar.com GSM: Handover