SEMINAR PRESENTATION

ON

MACROCELL-FEMTOCELL LTE NETWORK HANDOVER DECISION

ALGORITHM

BY

UMAR DANJUMA MAIWADA1

TABLE OF CONTENTS

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1) INTRODUCTION ………….………………..…………………………………………………….. 3

2) MACROCELL …………………………………………..…………………………………………….

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3) FEMTOCELL ………………………………………………………………………………………….

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Femtocell Network Architecture………………………………………………… 10

4) LTE ………………………………………………………………………………………………….. 12

LTE Network Architecture…………………………………………………………… 13

5) HANDOVER ………………………………………………………………………..…………….

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Handover Decision Algorithm…………………………………………………….

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Decision Making Parameters………………………….…………………………. 16

Advantages of Handover Decision Algorithm …………………………… 17

6) CONCLUSION …………………………………………………………………..…………………

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7) REFERENCES …………………………………………………………………………..…………

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INTRODUCTION

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• Due to the continuous rise in the number of mobile application users

worldwide, mobile operators face huge demands for mobile data services.

This has brought about a number of technological innovations that serve as

alternative to traditional broadband services. Nowadays, mobile devices are

pretty much used to carry out all sorts of functions; from accessing trending

applications like Facebook and twitter to video streaming applications like

YouTube all the way to voice over IP (VoIP) calls such as Viber, Whatsapp, and

stunt. In a network with nomadic users, this inevitably involves deploying

more infrastructures, typically in the form of microcells, hotspots, distributed

antennas, or relays.

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• Femtocells are low range, low power mobile base stations deployed by the

end consumers, which underlay the Macrocell system and provide a

solution to the problem of indoor coverage for mobile communications.

However, the deployment of Femtocells may introduce extra interference

to Macrocell base stations. An effective interference management

mechanism is required to optimize the system performance. One of the

enabling technologies for Long Term Evolution (LTE) deployments is the

femtocell technology. By having Femtocells deployed indoors and closer to

the user, high data rate services can be provided efficiently. These

Femtocells are expected to be deployed in large numbers which raises

many technical challenges including the handover management.

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MACROCELL• Macrocell is a cell in a mobile phone network that provides radio coverage

served by powerful cellular base station (tower).

• The antennas for macrocells are mounted on ground-based masts, rooftops and

other existing structures, at a height that provides a clear view over the

surrounding buildings and terrain. Macrocell base stations have power outputs

of typically tens of watts.

• Macrocell performance can be increased by increasing the efficiency of the

transreciever.

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Macrocell

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FEMTOCELL• Femtocell is a wireless access point that improves cellular reception inside a

home or office building. A femtocell is a miniature cell tower for homes or

small businesses that extends a carrier's traditional network's range.

• Femtocells connect to a carrier's network over the customer's broadband

internet connection and provide a strong local signal that cell phones in the

building can use for any of the typical voice or data applications.

• Femtocells require carrier support in order to be of any use. The Samsung

Ubicell1 (Sprint Airave) is an example of a commercially available femtocell.

Femtocells were originally called access point base stations.

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Femtocell

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Femtocell base station

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FEMTOCELL NETWORK ARCHITECTURE

• Service Parity: Femtocells support the same voice and broadband data services.

This includes circuit-switched services such as text messaging and various voice

features, such as call forwarding, caller ID, voicemail and emergency calling.

• Call Continuity: Femtocell networks are well integrated with the Macrocell network

so that calls originating on either Macrocell or Femtocell networks can continue

when the user moves into or out of Femtocell coverage.

• Security: Femtocell network architecture provides network access security, and

includes subscriber and Femtocell authentication and authorization procedures to

protect against fraud.

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Femtocells network architecture

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LTE

• LTE (Long-Term Evolution), commonly marketed as 4G LTE, is a

standard for wireless communication of high-speed data for

mobile phones and data terminals.

• LTE is synonymous to modern day telecommunication system; it is

a Fourth Generation (4G) mobile network.

• It is based on the GSM/EDGE and UMTS/HSPA network

technologies, increasing the capacity and speed using a different

radio interface together with core network improvements.

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LTE NETWORK ARCHITECTURE

• LTE has been designed to support only packet switched services, in contrast to

the circuit-switched model of previous cellular systems.

• The high-level network architecture of LTE is comprised of following three main

components: The User Equipment UE. The Evolved UMTS Terrestrial Radio Access

Network E − UTRAN. The Evolved Packet Core EPC.

• It aims to provide seamless Internet Protocol (IP) connectivity between User

Equipment (UE) and the Packet Data Network (PDN), without any disruption to

the end users’ applications during mobility.

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HANDOVER

• In cellular telecommunications, the term handover or handoff refers

to the process of transferring an ongoing call or data session from

one channel connected to the core network to another channel.

• Handover is the process of transferring active user equipment from

one base station to another. There are basically two types of

handover in mobile communication systems, soft and hard

handover.

• soft handover - make-before-break, Hard handover - break-before-

make.

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HANDOVER DECISION ALGORITHM• The main objective of handover algorithm is to decide an optimal

connection with respect to user or system performance, while

minimizing handover latency and the number of handovers.

• The handover decision algorithm can be utilized by a mobile station

(MS) moving from a Macrocell to a Femtocell. Here, it is assumed

that the MS has a capability to detect neighboring Femtocells.

• performing handover from a Macrocell to a Femtocell efficiently can

be seen as a way of increasing user satisfaction. The deployment of

Femtocells should not cause drastic changes on mobility

management procedures used in conventional Macrocell networks.

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DECISION MAKING PARAMETERS• Bandwidth is a measure of the width of a range of frequencies. Higher

the bandwidth, lower the call dropping and call blocking probability.

• Network Security: In a wireless environment, the security features

provided in some wireless products may be weaker; to attain the

highest levels of integrity, authentication, and confidentiality, network

security features should be embedded in the handover policies.

• Network throughput refers to the average data rate of successful data

or message delivery over a specific communications link. Handover to

the network which has higher throughput is desirable.

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ADVANTAGES OF HANDOVER DECISION ALGORITHM

• Performing handover from a Macrocell to a Femtocell efficiently

can be seen as a way of increasing user satisfaction. And the

Handover Decision Module interacts with the Channel Module in

order to get the needed RSRP measurements.

• The objective of handover algorithm is to decide an optimal

connection with respect to user or system performance, while

minimizing handover latency and the number of handovers.

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CONCLUSION

The growing demand for high-speed Internet connection has led to

major technological advancements, including Femtocell base stations.

Femtocell base stations are small inexpensive low power base cellular

base stations used for extending signals received from macrocells.

However, these deployments come with several challenges, including

but not limited to mobility management. Handover has proved to be

the most important property of mobility management for Femtocell

deployments in LTE networks.

REFERENCES

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[1] 3G LTE Tutorial - 3GPP Long Term Evolution. Radio-Electronics.com http://www.radio-electronics.com/info/cellulartelecomms/lte-long-term-evolution/3glte- basics.php. [2] 3GPP- TS 23.401 v9.4.0, “GPRS Enhancement for E-UTRAN Access”. 2010.[3] Andrews, J.G. et al., 2012. Femtocells: Past, Present, and Future. IEEE Journal on selected areas in communications, 30, pp.497-- 508.‐[4] D. Aziz and R. Sigel, “Improvement of LTE Handover Performance through InterferenceCoordination”, VTC 2009-spring, Barcelona, IEEE 2009.

THANK YOU

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