1. Femto Network Dr. Monir Hossen ECE, KUET Department of Electronics and Communication Engineering, KUET

2. Department of Electronics and Communication Engineering, KUET 2 What is Femto Cell? Why Femto Cell? History of Femto Cell Working of Femto Cell Femto Cell Basic Concept Features of Femto Cells Advantages of Femto Cell Femto Cell Interference Scenarios Handover Scenarios Agendas of This Lecture

3. Department of Electronics and Communication Engineering, KUET 3 What is Femto Cell? (1/2)  A small cellular base station in residential or small business environments  It connects to the service provider’s network via broadband (such as DSL or cable)  Typically it supports 2 to 5 mobile phones in a residential setting  It allows service providers to extend service coverage inside of your home - especially where access would otherwise be limited or unavailable - without the need for expensive cellular towers  It also decreases backhaul costs since it routes your mobile phone traffic through the IP network  It is sometimes referred to as a “home base station”, “access point base station”, “3G access point”, “small cellular base station” and “personal 2G-3G base station”

4. Department of Electronics and Communication Engineering, KUET 4 What is Femto Cell? (2/2)

5. Department of Electronics and Communication Engineering, KUET 5 Why Femto Cell? Technical motivations  Reduced separation distance between transmitter and receiver  Interference is isolated by building structure  Limited number of users Business motivations  Half of voice calls and a majority of data traffic originate indoor  Operators expand network capacity and coverage without much investments on infrastructure.  Subscribers get better radio service at low price

6. Department of Electronics and Communication Engineering, KUET 6 History of Femto Cell  The first interest in Femto cells were started around 2002 when a group of Engineers at Motorola were investigating possible new applications and methodologies that could be used with mobile communications.  In 2004, the idea was beginning to gain some momentum and a variety of companies were looking into the idea.  The Femto Forum was set up in July 2007. Its aim was to promote the wide-scale adoption of Femto cells.  The Femto Forum also played a coordinating role in ensuring that the standards were agreed and released as fast as possible.

7. Department of Electronics and Communication Engineering, KUET 7 Working of Femto Cell

8. Department of Electronics and Communication Engineering, KUET 8 Femto Cell Basic Concept Macro Cell

9. Department of Electronics and Communication Engineering, KUET 9 Features of Femto Cells  Operates in the licensed spectrum  Uses fixed broadband connection for backhaul  It is managed by the Network Access Point ( NAP)  The backhaul service provider may be different from NAP/NSP ( network service provider)  Principally intended for home and SOHO  Lower cost than PicoBS  Smaller coverage (low power) than PicoBS  Smaller number of subscriber (ten or less) than PicoBS  Higher density

10. Department of Electronics and Communication Engineering, KUET 10 Users Benefits -Reduced “in home” call charges -Improved indoor coverage (Base station in your bedroom) -Continued use of current handset -Reduced battery drain -Reduced call drops -Fast/Higher performance 3G services

11. Department of Electronics and Communication Engineering, KUET 11 Operators’ Benefits  Improves coverage  Reduces backhaul traffic  Provides capacity enhancements  Easy radio coverage for rural areas  Where there is ADSL you can have mobility  Stimulates 3G usage  Addresses the fixed mobile convergence market with a highly attractive and efficient solution  Reduces installation cost of new macro cell

12. Department of Electronics and Communication Engineering, KUET 12 Advantages of Femto Cell (1/2) 1.Low Device Cost: => Efficient, low-cost power amplifiers, highly sensitive receivers, flexible channel bandwidth, reliable RF filters, low cost and low power implementation, etc. 2. System Interference Management: => Minimize interference to macro (and vice versa), minimize interference to adjacent Femtos, coping with unplanned rollouts, coverage estimation, interference cancellation, etc. 3. Femto Cell Capacity Maximization: => Link and access management (handover, admission control, resource management, load balancing and flow control), dynamic bandwidth allocation and sharing, etc.

13. Department of Electronics and Communication Engineering, KUET 13 Advantages of Femto Cell (2/2) 4. Backhaul Issues: => Wired or wireless backhaul, reducing signalling load, QoS provisioning and traffic periodization, joint access and backhaul design, etc. 5. Viable System Architecture: => Control & data planes, access control, authentication, local breakout, efficient forwarding, seamless mobility, etc.

14. Department of Electronics and Communication Engineering, KUET 14 Femto Cell Interference Scenarios (1/2)

15. Department of Electronics and Communication Engineering, KUET 15 Femto Cell Interference Scenarios (2/2) FC MC 1 FC MC 2 FC  Irregular deployment will incur inevitable interference

16. Department of Electronics and Communication Engineering, KUET 16 Solutions to Interference Problem  Adaptive pilot power control  Dynamic Femto cell receiver gain management  Mobile phone uplink power overlaying/ Covering  Extended Femto cell receiver dynamic range

17. Department of Electronics and Communication Engineering, KUET 17 Handover Scenarios  There are 3 main scenarios for Femto cell handover:  Inbound (from the Macro cell to the Femto cell)  Outbound (from the Femto cell to the Macro cell)  From one Femto cell to another Femto cell

18. Thanks for Your Kind Attention Department of Electronics and Communication Engineering, KUET