femtocell case study

8/10/2019 Femtocell Case Study..

1/17


2/17

Small cellular telecommunications basestation that installed in residential orbusiness premise and also at rural areas

The idea is to overcome poor signalcoverage within building.

The first interest start around 2002 atMotorola. in 2004, the idea momentumwas begin and joined by variety ofcompany

Figure 1: Airvana Femtocell Figure 2: Femtocell target


3/17

Figure 3: How Femtocell work


4/17

Figure 4: Femtocell range where its used.


5/17

Subscriber Benefits Operator Benefitsa.Signal quality

I. Increase coverage, voice

quality & data speed

II. longer battery life

b. Cheaper minutes

(operator offers will vary)I. subscribers mobile 1

phone, 1 number no worries over minutes

II. eliminate 2nd line

III.family calling plans

a. Improve residential coverage at low costI. Reduce churn due to coverage issues

II. Improve CSAT(Customer Satisfaction)

III. Increase overall use

IV. low impact to macro BTS(base transceiver

station) capacity or backhaul

b. Reduced OPEX(Operational Expenditure) and

CAPEX(Capital Expenditure)I. Subscriber provides femto backhaul

II. Does not consume macro RF

III. Lower costs enable special femto rate plansIV. Increase stickiness of cellular services

V. Defense from VoIP (Voice Over Internet

Protocol)competition

Table 1: Femtocell benefit to both Subscriber and Operator


6/17

Uses users broadband IP or other Internet link such as DSL or

cable modems to link itself to the main core network. Acts like a small wireless access point and transmit data

cellular signal and voice within a home or in small space area.

Uses three major element in order to work

Femtocell access point (FAP)

It automatically sets up connections to the core network

using the broadband connection. This enable self-

configuration and self- optimization within the Femtocell.

Femtocell gateway

In Femtocell gateway, a security gateway will act to

terminate large numbers of encrypted Ip data connections.


7/17

The management and operation system

This system allows software updates and diagnostic checks

to be administered for the Femtocell.

Figure 5: The architecture of the Femtocell


8/17

In common WCDMA Femtocells the interface that is

used is lu-h interface. In lu-h architecture, the

Femtocell gateway is installed between the Femtocelland the service network.

Femtocell gateway functions is to carry out the

essential translation to make sure the Femtocells

emerge as a radio network controller to existingmobile switching centers.

Femtocell will transfer the information to the

Femtocell gateway and the Femtocell gateway willconnect with the core network emulator (CNE) such

as Mobile Circuit Switching (MSC) for circuit-switched

calls and Serving GPRS Support Node (SGSN) for

packet-switched calls.


9/17

In 3rdGeneration partnership Project (3GPP) term, a Home Node B

(HNB) is a 3G Femtocell.

Femtocell will provide a good 3G coverage for the user

consequently effective indoor coverage can be achieve.

Figure 6 : 3G HNB


10/17

Home NodeB (HNB)

The HNB will take in the competency of a standard Node-B as well

as radio resource management used within a Radio Network

Controller (RNC).

HNB Gateway (HNB-GW)

The function of the HNB-GW is to provide authentication and

certification to allow only to and from authorized HNB. It is also to

combine traffic from a large number of HNBs and produces a wayin point into the operator core network. Other function is to assign

a mechanism to maintain enhanced features such as other IP

based synchronization.

Iu-h interface

The function of this interface is to provide the link that secure the

connection of HNB with the HNB-GW. The lu-h interface also

includes a new HNB Application protocol.


11/17

Still on its way. Even Macro Cellular networkcannot meet 4G demand because:

Limitation to built cell site

The spectrum available to any particularoperator is limited

Expensive backhaul cell site

If it going to be produced, it will be in2G/3G/4G multimode due to mobileconsumption.


12/17

Figure 7 : Estimate type of mobile consumption


13/17

1. Interference issues

It is essential that Femtocells are capable to working within the normal spectrum shared

with other cellular base station. This can be achieved using many methods such as theuse of 3G and 4G that are able bear with interference and working in single channel, the

use of cognitive radio technology and planning spectrum where possible.

2. Spectrum issues

Setting up the available spectrum so that it can be used with the large numbers of

Femtocell has to put into consideration although sometimes single channel operationwith main core station maybe needed.

3. Regulatory issues

Femtocells will require regulatory approval in order to work. That is because Femtocell

operate in licensed or regulated spectrum and this is controlled by the service provider.

So, the radio and spectrum regulation vary from one country to the next country.

4. Health issues

Femtocell acts as a small cellular base station. So it will receive RF radiation. However,

Femtocell emit only a small amount of power and it is not greater than the typical Wi-Fi

access points which are familiar in many homes.


14/17

1. Base station interfering with Femtocells or

otherwise on the same frequency.

happen when both of Femtocells and macro base station operating on

the same channel. Its reducing the network performance

2. Closely spaced Femtocells with each other

There will be noises and reducing Femtocells sensitivity.

3. More than one base station received high power

transmitting user equipment. Even the coverage inside the building using Femtocell, there will still

signal from mobile reach the base station. It will increase the overall

base station noise.


15/17

1. Adaptive Pilot Power control

Femtocell will detect the signal from its surrounding cell and adjusts its own

transmitter power while still maintaining it own coverage area.

2. Dynamic Femtocell receiver gain management

An automatic gain is introduced to the system in order to enable the mobile tooperate without increasing their transmitted output power. This will the noise

and interference at minimum.

3. Mobile uplink power capping

The maximum power output of the mobile when operating in the Femtocell

environment is capped. This is to make sure that the phone hand off to the macronetwork before transmitter power rises and produces noise.

4. Extended Femtocell receiver dynamic range

A standard of 3GPP of 25.104 is introduced for the Femtocell to operate reliably

even with the presence of nearby high power mobile phone connected to the

macro network.


16/17

In conclusion, Femtocell acts similar to the DSL-modem

means to provide the connection to the user in the home but

Femtocell operate differently by using internet connection to

connect the user to the core base station.

Femtocell will provide a low-cost, small, low power unit and

can be self installed by the user to provide a good and reliable

3G coverage to home.

Femtocell also will improve data download and upload speed

of the user.

Femtocell also has the ability to detect presence and do the

connection to the home network.


17/17

Allan, R. (2008, November 17). mobiledevdesign.com. Retrieved February 8, 2014,from mobiledevdesign.com: http://mobiledevdesign.com/learning-

resources/femtocells-get-ready-invade-homes-and-offices

Diaz, S. (2008, December 9). http://www.zdnet.com. Retrieved February 10, 2014,

from http://www.zdnet.com: http://www.zdnet.com/blog/btl/at-and-t-testing-

femtocells-to-boost-in-home-cell-phone-signals/11167

Pemmaraju, S. K. (2008, December). Nortel. Retrieved February 8, 2014, from

Nortel: http://www.ieee-

globecom.org/2008/downloads/DD/DD15W2%20Femtocells/DD15W2_Pemmaraj

u%20S.pdf

Poole, I. (n.d.). Radio-Electronics.com. Retrieved February 8, 2014, from Radio-

Electronics.com: http://www.radio-electronics.com/info/cellulartelecomms/femtocells/femto-cells-tutorial-basics.php

realwireless. (2008, June 8). http://www.realwireless.biz . Retrieved February 8,

2014, from http://www.realwireless.biz:

http://www.realwireless.biz/2008/06/06/3g-femtocells-gain-clarity-on-

standardised-network-architecture/

femtocell case study

Documents