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1PRIVATE AND CONFIDENTIAL 2013 CommScope, Inc

March 2014

Dr. Rikin ThakkerEngineering Services Group

Fundamentals of CellularCommunication


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Introduction:

Description:

Foundation theories of Cellular Communication are important yet oftenoverlooked domain in todays wireless world. This course provides a

footing of Radio Frequency (RF) theories and practices of todays

cellular systems.

Intended Audience: Personnel without any Cellular/RF background

Personnel who want to revive their learning of RF fundamentals

Personnel with enhanced RF knowledge who want to learn about CellSite Design and Measurements

Instructors Bio:

Dr. Rikin Thakker, CommScope, Inc.


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Course Content:

Day One: (4 Hrs)

Fundamentals of RF Communication

RF Propagation Characteristics

Basic RF Principles

Modulation Schemes

Introduction of Cellular Technologies:

GSM, UMTS, CDMA, LTE, LTE-A

2G, 3G and 4G Standards by ITU

Cellular Technology Evolution Path International Standardization

ITU, FCC, 3GPP

Roles and Responsibilities

Other Key Players

Mobile Backhaul Options

T1/E1, Fiber, Microwave Links Cellular/Wireless Connectivity

Link Budget AnalysisUplink vs.Downlink, Path Loss

Signal-to-Noise Ratio

Foot PrintCoverage

Day Two: (4 Hrs)

Spectrum

Frequency Assignment

Cellular Bands in the U.S.

Radio Channels

Data Rates and Capacity

Cell Site Design and Components

What is an RF Plumbing Diagram?

Components at a typical cell site: Antennas,Jumpers, Feeders, Filters, Combiners,

Amplifiers, etc.

What is Co-Siting?

Why is it needed?

How to read an RF Data Sheet

RF Measurements at a Cell Site

Line Sweep Fundamentals

Return Loss, VSWR, Insertion Loss, Gain

PIM (Passive Intermodulation Measurement)

AISGIntroduction and Components

E911 and Location Based Services


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Setting the background first:


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45 percent of the

worlds populationwas covered by a 3G

mobile network-

according to The ITU

(2011).

50 percent of the

world's population will

be covered by 4G in

2017


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How does Ranking getdecided?


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Top 10 US Tower Companies

Source: WirelessEstimator.com

Date: 01/23/2014

Total Companies: 87

Total Towers: 101,763

Cellular Infrastructure:


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Cell Site Infrastructure: Very Important

CTIA: Carriers continue theirinvestments in their networks andinfrastructure to improve theircustomers coverage and speeds.

From June 2011-June 2012, theannual capital investmentincreased to $26 billion.


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Article: Grading thetop 10 US Carriers in3Q of 2013

Source: Strategy

Analytics Date: November,2013

This list does notinclude resellers or

MVNOs such asTracFone.


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Fundamentals of RF Communications:


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Two Way Communication

Up Link

Tx Signal

Rx Signal

Down Link

Where is Tx and Rx?


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RF Fundamentals:

An electrical signal is generated by Transmitter; Tx Antenna will

convert that signal into Electromagnetic wave (aka RF wave) whichwill radiate.

RF wave propagates (moves through matter and/or space) and ispicked up by the Rx Antenna which converts the RF wave intoelectrical signal


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RF Characteristics:Amplitude and Wavelength

Amplitude

Wavelength

Time

Loss of AmplitudeGain of Amplitude


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Wavelength, Frequency, and Velocity


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RF Signal Measurements:

Amplitude: Power of the wave.

Higher is better for Rx Antenna to interpret the signalproperly

Receiver Sensitivity: More details during Link BudgetAnalysis

Watt, milliWatt, dBm, dBd, dBi, dB

Units of Absolute Powerwatt, milliwatt, dBm

Are used to measure Tx and Rx amplitudesAbsolutePower

Units of relative comparisondB, dBi, dBd

Are used to measure how much gain or loss due to inlinecomponents (cable, antenna etc)Change in Power


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Units of Absolute Power

Watt1 Amp of current flowing at 1 Volt.

Milliwatt1/1000 of a watt

dBmPower of signal compared to 1 milliwatt It is the decibel reference with respect to 1 mWatt


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Milliwatts and Watts Vs dBm:

mWPdBm 10log10

mW dBm

10 10

100 20

1 0

1000 30

5 7

Transmitted PowerReceiver Sensitivity

Watts dBm

10 40

20 43

5 37

40 46

80 49


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Units of Relative Comparison

dB:Represents difference in two values.

Indicates change in power

dBi:Gain of an antenna relative to a theoretical Isotropic

Radiator. dBd:Gain of an antenna when it is compared to the signal

of a dipole antenna.A dipole antenna has a dBi value of 2.14 So, a 2 dBd antenna = 4.14 dBi

)/(log10

)/(log

2110

2110

PPdecibels

PPBels


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Amplitude:

Signal Strength or Power

Loss of amplitudeAttenuation / Loss Increase in amplitudeGain

Tx Amplitude and Rx Amplitude are always different due to Path Lossand many other factors

Signal also loses amplitude when it travels through confined medium,

i.e. wires, cablesLoss due to cables and connectors


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Example values of Amplitudes:

Few examples of different amplitudes for different

applications Mobile Communication at PCS frequencies (1900 MHz)Tx

Power ~ 20 Watts

AM Radio Stations at 750 KHzCan Tx at 250 Watts to 50,000

Watts Radio Cards for indoor Access Points for 802.11Can Tx from 1

mWatt to 100 mWatt

Signals of same frequencies can have differentamplitudesbecause of different application

WiMax Vs Wi-Fi

Cell Foot-Print is the key factor


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Gain:

A.k.a. Amplification

Increase in signal strength or amplitude Two types

Active Gain Passive Gain

Active Gain: use of external Amplifiers to boost signal strength External Amplifiers need external power source to operate

Concept applies to bothTx and Rx signals Example: Tower Mounted Amplifiers Active device

Passive Gain: gain achieved through sending RF signal into certaindirection

Example: Antenna Doesnt require external power source to operate

Passive device


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Loss:

A.k.a. Attenuation

Decrease in Amplitude When signal travels through Wire/CableElectrical Impedance decreases signalstrength

Concept of Insertion Loss

When RF travels through airAbsorption,Multipath, Distance etc causes signal to losestrength

RF also encounters loss in signal strength asit travels through airas a function ofdistance

Free Space Path Loss


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Frequency Vs Wavelength:

Wavelength = Distance Required to Complete One Cycle (mm, cm)

Frequency = Number of Cycles per Second (Hz, MHz, GHz) Radio Waves move at speed of light.

c = 300,000,000 meters / second

Inverse relationship between Wavelength and Frequency

Higher the Frequency, Smaller the wavelength..(1)


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F0(MHz) (Meters)(Inches)

30 10.0 393.6

80 3.75 147.6

160 1.87 73.8

280 1.07 42.2

460 0.65 25.7

800 0.38 14.8

960 0.31 12.3

1700 0.18 6.952000 0.15 5.9

Frequency Vs Wavelength:


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Wavelength/Frequency Vs Attenuation:

Electromagnetic signals travel forever in a vacuum

In real worldno vacuum there are matters, objects, atmosphere

As RF propagates through space and matter, it loses signal strength(it attenuates)

An RF signal with smaller wavelength will attenuatefaster..(2)

Higher frequency signal (smaller wavelength) will not travel asfar as the lower frequency signal (largerwavelength).....(3)

Both (2) and (3) assume equal amplitude (power level) at theTx Antenna


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Wavelength/Frequency Vs Penetration:

Higher the frequency, the less it will penetratethrough obstructions.(4)

AM Vs FM Radio

AM wave of 750 KHz has wavelength of 400meter

FM wave of 88.5 MHz has wavelength of 3.39meter

You can hear AM station much farther than FMstation. (Using all four principles)


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Amplitude:

Higher frequency signal (smaller wavelength) willnot travel as far as the lower frequency signal(larger wavelength).....(3)

Does this mean that two signals of same

frequencies travel same distance? What is missing?Amplitudes of both signals

Higher the amplitude of wave, the more powerfulthe wave is and the farther it willtravel..(5)


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Basic RF Principles:

1. Higher the Frequency, Smaller the wavelength

2. An RF signal with smaller wavelength willattenuate faster

3. Higher frequency signal (smaller wavelength)

will not travel as far as the lower frequencysignal (larger wavelength)

4. Higher the frequency, the less it will penetratethrough obstructions

5. Higher the amplitude of wave, the morepowerful the wave is and the farther it will travel


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Why do we need to know all these?

During the design phase

Before designing, perform a site survey

Know the technology and frequency band you are using

Coverage can be defined by received signal strength at

various points in your cell foot-print

Optimize the number of Cell Towers Which band will need more Cell Towers for given area?

1900 MHz

850 MHz

700 MHz

Mobile Communication:


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Mobile Communication:Frequency Bands in the U.S.

Cellular: 800 MHz

PCS: 1900 MHz

AWS: 2100 MHz

700 MHz (LTE)

Technology is not frequency dependent.-GSM can be deployed in 850 and 1900

MHz band-LTE can be deployed in 700 and AWSband


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Frequency Bands:


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Uplink Vs Downlink

Cellular (800 MHz) band:

Uplink: From Mobile to Cell Tower 824 to 849 MHz

Downlink: From Cell Tower to Mobile 869 to 894 MHz

PCS (1900 MHz) band: Uplink: 1850 MHz to 1910 MHz

Downlink: 1930 MHz to 1990 MHz

AWS (2100 MHz) band: Uplink: 1710-1755 MHz

Downlink: 2110-2155 MHz

Notice any similarity?

- Uplink frequencies are lowerthan Downlink frequencies.


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Uplink Vs Downlink: 700 MHz


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Uplink Vs Downlink: 700 MHz

Downlink Frequencies are lower in 700 MHz band


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Uplink Vs Downlink (Conti..)

Different Frequency Band

Different Link Budget Link Balance is necessary

To match Foot Prints

Hand-over consideration

To reduce Dropped Calls


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Source: Ehud Gelblum, Morgan Stanley Research


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With 700 MHz spectrum, a wireless carrier in an urban area may need 50%fewer cell towers to cover the same wireless service area.

Fewer towers mean lower capital and recurring expenditures for wirelesscarriers.


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What is a Cell Site?

Tower, Mono Pole

Antennas Dish Antenna

Cables

A Tiny-Room

Or a Cabinet(a.k.a. Shelter)


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Up Link

Tx Signal

Rx Signal

Down Link

What is a Cell Site?

Shelter


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Types of Cell Site

IndoorWithin Shelter (most common)

OutdoorOutside Shelter

Roof-top Sites

Micro Cell

In-Building Site (DAS)

COW (Cell On Wheel)

COLT (Cell on Light Truck)

Femto Cell


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A Mono Pole Tower


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Cell Site in a Church


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Cell Site in a Church

A three sector Palm-Tree Tower:
http://upload.wikimedia.org/wikipedia/commons/a/a0/BTS_NodeB_antenna_Sopot.jpghttp://upload.wikimedia.org/wikipedia/commons/a/a0/BTS_NodeB_antenna_Sopot.jpghttp://upload.wikimedia.org/wikipedia/commons/a/a0/BTS_NodeB_antenna_Sopot.jpg


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A three sector Palm Tree Tower:(Bionics Monopole)


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Photo Credit: Tower Systems Inc. andNational Association of Tower Erector


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Photo Credit: WesTower Comm. and

National Association of Tower Erectors


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Photo Credit: Crown Castle


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Photo Credit: Crown Castle


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Roof-top Site


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52PRIVATE AND CONFIDENTIAL 2013 CommScope, Inc Cell On Wheel (COW)


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Three Sector Tower


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Indoor Shelter


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Cell Site Components:

BTS / NodeB / eNodeB Peripheral Components

Vendor Neutral

Power Amplifiersin Tx Line

Tower Mounted Amplifiers (TMAs)in Rx Line

Antennas and Tilt Controlling Components

Filters and Combiners

Multicouplers

Diplexers and Duplexers

Power Sources, Bias Tees

Cables and Connectors RF and Power Measurements at Cell Site

Alarming Scheme, Lightning Protectors, Grounding Material


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Down Link

- LL

Tx Power

+ ANT gain

-CL

- Path Loss

Rx Threshold

-CL

EIRP

Link Budget: Down Link


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Path Loss:

For an Electromagnetic Wave, Path Loss is:

Reduction in Power Density while it propagates through space.

Major component in Link Budget.

Due to:

Free Space Loss Refraction

Diffraction

Reflection

Coupling LossAbsorption


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Free Space Path Loss: (FSPL)

Free space path loss results from sending a RF signal

over the air: The further you go, the weaker the signalgets.

Loss in signal strength as a function of distance

Due to Natural Broadening of Wave, as it travels

It attenuates even if it doesnt encounter Absorption, Reflections,Refractions.

A.k.a. Beam Divergence

Decrease in amplitude is Logarithmic and not Linear

Amplitude doesnt decrease as much in second segment of equallength as it decreases in the first.

E.g. at 2.4 GHz, lets assume its -80dB in first 100 meters; only -6dB in next 100 meters


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Any Radio Receiver, either FM, Cellular or

Satellite, has a fixed amplitude threshold, calledRx Sensitivity, below which it can not detect thesignal.

If they receive a signal above this threshold, they

can differentiate between the received signal andbackground RF noise (noise floor).

Need to make sure that the received signaldoesnt fall below Rx Sensitivity Threshold just

because of FSPL. FSPL : Important parameter for Link Budget



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d = distance from Tx (m)f = frequency of the signal (hertz)


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d = distance from Tx (kilometers)f = frequency of the signal (MHz)

6 dB rule: Doubling the distance from Tx will result in a loss of 6 dB

At 2.4 GHzAt 1 kmFSPL is 100 dBAt 2 kmFSPL is ~106 dBAt 4 kmFSPL is ~112 dB

dBis the difference in power levelLoss and Gain can be represented in a relative

measurement of change in power(dB)

3 dB rule:


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Milliwatts Vs dBm:

1 milliwatt is the reference point0 dBm

+ve value of dBm amplitude is greater than 1 mW -ve value of dBm amplitude is less than 1 mW

E.g. Tx value of 100 mW

i.e. +20 dBm

FSPL ~ 60 dBm

Rx value = -40 dBm

i.e. 0.0001 mW

dBm calculations are easier to understand Makes it easier for Link Balance Calculations


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Insertion Loss:

The loss in power due to the insertion of a

component or device in a transmission system.

Expressed as the ratio in decibels (dB) of thepower received at the load before insertion of the

component, to the power received at the loadafter insertion.

Connector Loss, Line (Cable) Loss


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Connector and Cable Loss:

Loss of energy at connector

Inevitable: No matter how

perfect the connection wasmade

Connector

Cable


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Connector Specification:

Cable (Line)


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Performance:

Link Budget Calculation:D Li k


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Down Link

Tx Power: 45 dBm

Connector Loss: -0.5 dBm

Line Loss: -2.5 dBm

ANT gain: 17 dBi

EIRP = 59 dBm

Path Loss ~ 160 dB

45 dBm

44.5 dBm

42 dBm

59 dBm

Signal reaching to your mobile = 59 dBm160 dB = -101 dBm

Net Value

Li k B d t D Li k


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Down Link

- LL

Tx Power

+ ANT gain

-CL

- Path Loss

Rx Threshold

-CL

EIRP

Link Budget: Down Link

R Th h ld t M bil


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Rx Threshold at Mobile:

In this case, it has to be better than

-101 dBm - 99 dBm

(NO)

-103 dBm

(YES)

Link Budget: Up Link


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- LL

Tx Power

+ ANT gain

-CL

- Path Loss

Rx Threshold

-CL

Up Link

Link Budget: Up Link

Link Budget Calculation:U li k


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Uplink

Tx Power: 32 dBm

ANT gain: 17 dBi

CL, LL: -3.0 dBm

Path Loss ~ 160 dB

32 dBm

49 dBm

46 dBm

Signal reaching to BTS = 46 dBm160 dB = -114 dBm

Net Value

R Th h ld t BTS


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Rx Threshold at BTS:

In this case, it has to be better than

-114 dBm What if Rx Threshold for BTS is -104 dBm ??

TMA i U li k Li it d N t k


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Downlink

RangeUplink

Range

TMA in Uplink-Limited Network

Usable coverage area is definedby the uplink range

Downlink range is larger due tohigh power BTS transmitter

A Tower Mounted Amplifier is ahearing aid for the BTS receiver

Improves sensitivity

Extends coverage range

Expands coverage area

What is a TMA?


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What is a TMA?

A Bandpass Filter and Low Noise Amplifier (LNA) mounted near thereceiving antenna

The best solution for improving uplink performance before it is degradedby feeder loss

Can be easily retrofitted on existing sites

An optional enhancementbase station can operate without it.

Maximizes service at minimum cost

Compatible with all air interface standards Dual Duplex TMAs allows transmit on the same feeder and antenna

Todays TMAs are Dual Duplex

Other names TTATower Top Amplifier

TTLNA MHAMasthead Amplifier

TMA benefits


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TMA benefits

Functionality: What does the TMA do?


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Functionality: What does the TMA do?

Provides gain to Uplink Signal

Improves BTS receiver sensitivity by lowering the system noise figure

Improves interference immunity by

Providing additional filtering

Reducing handset transmit power

Improves cell capacity by reducing total spectral density Enables increased data rates by raising signal-to-noise ratio

Advantages: Why use a TMA?


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Advantages: Why use a TMA?

Better call quality

Better data throughput Longer battery life of Handset

Improved coverage at fringe areas

Increased capacity in networks

Higher customer satisfaction

Increased air time and revenue


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Cellular Technologies:

Wireless Generations:


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IS54/IS136

WiMAX

IS95(CDMA One)

IS95B (CDMA2000)

EVDO

AMPS

GSM

GPRS/EDGE

UMTS

HSPA / HSPA+

LTE

1G

2G

2.5G

3G

3.5G

4G

Wireless Generations:

International Standardization


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International Standardization

ITU (International Telecommunication Union) Radio standards and spectrum

IMT-2000

ITUs umbrella name for 3G which stands for International Mobile

Telecommunications 2000

National and regional standards bodies are collaborating in 3G

partnership projects

ARIB, TIA, TTA, TTC, CWTS. T1, ETSI

3G Partnership Projects (3GPP & 3GPP2)

Focused on evolution of access and core networks

3GPP:


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3GPP:

Third Generation Partnership Project

Partnership of 6 regional standards groups, which translate3GPP specifications to regional standards.ITU references the regional standards.

2G GSM:


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Global System for Mobile (GSM) is a second generation

cellular standard developed to cater voice services and datadelivery using digital modulation, replacing the

incompatible analog system.

Full set of specifications phase-I became available in 1990

User/ terminal authentication for fraud control andencryption of speech and data transmission over radio path

are its main features

Supports full International roaming along with SMS

Today many providers all over the world use GSM (morethan 135 countries in Asia, Africa, Europe, Australia,

America)

2G GSM:

GSM Specifications:


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RF Spectrum:

GSM 850-Mobile to BTS (Uplink): 824-849 Mhz

BTS to Mobile (Downlink): 869-894 MHz

Bandwidth: 2*25 MHz


BTS to Mobile (Downlink): 935-960 Mhz

Bandwidth: 2*25 Mhz


BTS to Mobile (Downlink): 1805-1880 Mhz

Bandwidth: 2*75 Mhz

Carrier Separation: 200kHz

Duplex Distance: 45 MHz No. of RF Carriers: 124

Access Method: TDMA/ FDMA

Modulation Method: GMSK

Modulation Data Rate: 270. 833 Kbps

GSM Specifications:

Handovers:


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Between 1 and2- Inter BTS/Intra BSC

Between 1 and3- Inter BSC/Intra MSC

Between 1 and4- Inter MSC

Handovers:

Two Segments of MobileCommunication:


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Communication:

A mobile cellular communication system can be divided into two

segments: a radio access network that performs air-interface related

functions and

a core network that performs switching functions and interfacesto external networks such as the Internet or a public-switched

telephone network (PSTN)

Source: Altera

Evolution:


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Evolution:

The evolution to next-generation technology is taking

place in both the radio access network and the corenetwork.

3G - air interface standards include W-CDMA andcdma2000-1X.

The corresponding wireless networks are universalmobile telecommunication system (UMTS) andcdma2000.

UMTS Wireless NetworkInfrastructure


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Infrastructure

The universal mobile telecommunication system (UMTS)

is a 3G wireless system that delivers high-bandwidth dataand voice services to mobile users.

Evolved from global systems for mobile communications (GSM).

UMTS has an air interface based on W-CDMA

And, Internet protocol core network based on general-packetradio service (GPRS).

Source: Altera

Voice and data transport is performed by the transportlayer nodes, colored blue:Node B = Base transceiver station (BTS)RNC = Radio network controller or base station controller(BSC)SGSN = Serving GPRS support nodeGGSN = Gateway GPRS support nodeMGW = Media gatewayThe call control function is mainly performed by the callcontrol layer nodes, colored yellow:CSCF = Call state control functionMGCF = Media gateway control functionHSS = Home subscriber server

Mobile Communication:Base Station


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Base Station

GSM (2G): BTS

UMTS (3G): Node B LTE (4G): eNB

Would you be able to see GPRS and EDGE BTS or NodeB in theplumbing diagram?

How about HSPA?

3.5 G Radio Network Evolution


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High Data rate, low latency, packet optimized radio access

Support flexible bandwidth up to 20 MHz, new transmission schemes,advanced multi-antenna technologies, and signaling optimization

Instantaneous peak DL 100 Mb/s and UP 50 Mb/S within 20 MHz

spectrum

> 200 users per cell within 5 MHz spectrum

Spectrum flexibility from 1.25 MHz to 20 MHz

Eliminate dedicated channels; avoid macro diversity in DL

Migrate towards OFDM in DL and SC-FDMA in UL

Support voice services in the packet domain

3.5 G Radio Network Evolution


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GSM Evolution:


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GSM Evolution:

Wireless Technology Evolution Path:


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e ess ec o ogy o ut o at

Engineering GK: What is 4G?


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Following a detailed evaluation against stringent technical and operational

criteria, ITUhas determined that LTE-Advanced and WirelessMAN-Advanced

should be accorded the official designation of IMT-Advanced. As the mostadvanced technologies currently defined for global wireless mobile broadband

communications, IMT-Advanced is considered as 4G, although it is recognized

that this term, while undefined, may also be applied to the forerunners of

these technologies, LTE and WiMAX, and to other evolved 3G technologies

providing a substantial level of improvement in performance and capabilities with

respect to the initial third generation systems now deployed.

What the ITU basically said was that while it has defined what 4G will look like,

those technologies that provide superior performance to what was seen as

standard 3G can also call themselves 4G.

In other words, all of those carriers that are now calling their not officially

recognized 4G technologies 4G can continue to do so even though they really

aren't.

g g

Engineering GK: What is 4G?


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The ITU in 2003 noted in a report that 3G technology provided a

minimum speed of 2 [megabits per second] for stationary or walkingusers, and 348 [kilobits per second] in a moving vehicle.

So, that would mean that 4G could be any technology that provided aminimum speed of 2.00000001 Mbps for stationary or walking users

and 348.0000000001 Kbps in a moving vehicle.

g g


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With 38 frequency flavors, LTEwont unify4G


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y

http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/

ATT to use 704-746 MHz

VZW to use 746-787 MHz

Future of 2G and 3G:
http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/http://gigaom.com/mobile/with-38-frequency-flavors-lte-wont-unify-4g/


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REMEMBER: 2G and 3G are not going away

Source: Ericsson MobilityReport

LTE Progress around the World:


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g

US lags in LTE Network Speeds

20thFeb, 2014 Source: RCR Wireless

The United States trails 13 countries when it comes to LTE network speeds according to the latest OpenSignal report.

The report found that average LTE network speeds in the U.S. have declined 32%this year.

6.5 Mbps posted by the United States The operators struggled to keep pace with increasing data downloads.

Australia posted the fastest LTE speeds an average download speed of 24.5 megabits per second.

Last year the U.S. ranked 8th in the OpenSignal study, with an average LTEnetwork download speed of 9.6 Mbps.

Many of the nations with faster speeds than the United States do not have asmuch LTE coverage.

AT&T Mobility and VZW, which together have roughly 200 million subscribers, areboth nearing completion of their LTE roll outs with more than 300 million potentialcustomers covered.

LTE Progress around the World:


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Source: OpenSignal

g


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Backhaul Options:

What is Backhaul?


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Rapidly increasing growth in data traffic across mobile infrastructure

continues to stretch networks to their limits. A critical part of thenetwork design is backhaulnamely taking the traffic from the

cell site back to the core.

What do we mean by core?

Typically, one of three technologies is used for backhaul:

1. Copper: with its limitations in capacity and reach;

2. Fiber: which can be prohibitively expensive to deploy; and

3. Microwave: To date, microwave has been the technology of

choicean excellent combination of reliability, cost and rolloutspeed has given microwave the dominant position in mobile

infrastructure backhaul.

For 2G, 3G and 4G:


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In existing cellular networks, RAN backhaul is defined as the connection between

the radio at the cell site and the radio controller.

Backhaul comprises the "last mile" between the base station and the base station

controller (BSC) or radio network controller (RNC), as well as the transport network

between the BSC or RNC and the core network. This backhaul network can bedelivered by any number of methods or can be outsourced fully or partially to third-party wholesale network providers.

Core Network:


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The core network is responsible for setting up and controlling connections between mobile

or fixed line customers attached to access networks by locating the called party and routing

voice calls towards it.

Additionally, the core network handles data traffic by allowing customers to access service

platforms offering services such as Facetime, web browsing, email, mobile TV and other

data related services.

The core network comprises three domains:

The Circuit Switched domain enables voice and video calls. Its key nodes are switches(which manage the set-up of connections) and user databases.

The Packet Switched domain allows customers to use data services. Its key nodes are

responsible for a variety of functions, such as the delivery of data packets to and from

mobile devices within a geographical service area.

The IP Multimedia Subsystem (IMS) domain is the first step of a wider evolutionary pathfrom the current core network to an all internet protocol (IP) next generation network. It

enables delivery of advanced multimedia services, both mobile and fixed, leveraging the

flexibility and effectiveness of internet technologies.

Access Transmission Network:


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Microwave radio network design is a subset of activities thatconstitute overall transmission network design.

Transmission networks are AKA:

Transport networks

Access networks

Connectivity networks

Different wireless operators use different names

For wireless operators, wireline transport (T1/E1) is one option

Microwave is preferred due to many reasons

Need for improved Backhaul Solutions:


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Backhaul plays a critical role in mobile broadband

Heterogeneous networks (known as hetnets) Small cells

Deploying vast numbers of small cells to complement improved anddensified macrocell layers will require a range of highly scalable,flexible mobile backhaul solutions that support superior user

experience.

Demand:


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Mobile Data Demand Scenarios:

In the few years since smartphones have been commerciallyavailable, shipments have risen drastically, reaching almost 500

million units in 2011, when they surpassed PC shipments for the first

time.

Smartphone users are consuming more data than ever before: an

average of about 300MB per month, and have downloaded more than15 billion applications from Apples App Store alone since it first

opened for business in 2008.

Smartphone shipments, bandwidth-heavy services and rising

popularity of applications are some of the drivers behind the tenfoldincrease that is expected in mobile traffic during the next five years

reaching a projected global monthly total of almost 5,000 petabytes by

the end of 2016.

Demand:


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Source: MobileDevDesign.com

Increasing Backhaul capacity & speed


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Cisco Systems in its latest global mobile traffic study, asserted that

from 2010-2015,

Global mobile traffic will grow at a 92% CAGR.

Global traffic will go from 0.24EB/month to 6.3EB/month.

Mobile n/w connection speed will go from 215 Kbps to 2.2 Mbps and

smartphone speed will reach 4.4 Mbps.

Backhaul capacity should be increased.

Backhaul speeds

HSPA/HSPA+: 30 Mbps Backhaul

LTE: 50-110 Mbps Backhaul

RAN Vs Spectrum:


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Spectrum limitations in the radio access network (RAN) mean that themaximum capacity per cell site is limited

the only way to further increase the bandwidth supplied to each user isto increase the density of cell sites.

This approach reduces the number of users per cell site and allowseach user access to a larger portion of a cell sites capacity.

To achieve this, operators are adopting Wi-Fi offload and small-celldeployment strategies.

Backhaul Solutions:


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Some solutions to meet the data demand:

Deploying more advanced HSPA and LTE technologies; Gaining access to additional spectrum;

Implementing techniques that are more spectrum-efficient;

Densifying the macro layer.

However, continued enhancement and densification may not alwaysbe the most cost-efficient way to boost capacity at hotspots and

improve performance indoors and at cell edges.

additional capacity can be provided by deploying small, low-power cells

that cover less extensive areas. Tens of thousands of these cells could

potentially be deployed in dense mobile networks in urban areas.

Backhaul Solutions:


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With the arrival of small cells on the scene, backhaul requirementsare once again in the spotlight.

Challenges:

Deploying small cells to boost capacity in hotspots and inside buildingswill off-load the macro layer and support the delivery of ubiquitous,constant connectivity.

The backhaul should not limit the radio access network and should have

sufficient end-to-end performance to meet the desired user quality ofexperience (QoE) everywhere.

This is valid for backhaul of mobile networks today, and will be equallyimportant for backhaul in both the macro and micro layers of a hetnet inthe future.

Backhaul Challenges:


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The new network realities of higher cell-site capacity and higher cell-site density are dramatically changing backhaul requirements.

First, the data format has changed from T1/E1 interfaces on 2G and3G basestations to Ethernet interfaces, forcing a move to all-IP(Internet protocol) backhaul technologies.

Second, the capacity per site is increased to several hundred

megabits per second, driving the need for higher-capacity radios orthe move to fiber-based backhaul.

Backhaul Solutions:


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Selection of backhaul solution:

Ongoing development of radio networks to maximize

the use of available spectrum puts greater demands

on delay, delay variation and synchronization

particularly between the macrocells and small cells.

Such performance requirements impact the choice ofbackhaul solution for a given scenario, where the

best solution will result from a holistic view of the

network.

Backhaul Solutions:


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Three ways to enhance performance

Source: http://www.ericsson.com/res/docs/whitepapers/WP-Heterogeneous-Networks-Backhaul.pdf

Backhaul Solutions:


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Backhaul Technologies:

Line-of-sight (LOS ) microwave

Non/near LOS (NLOS) microwave

Point-to-point (PTP) fiber

Point-to-multipoint (PMP) fiber

Category 5/6 LAN

Digital subscriber line (DSL) technologies.

Backhaul Solutions:


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When you're looking for alternatives to T1 lines, microwave backhauloffers far greater flexibility, improved system performance, greatercontrol and lower operating costs.

Comparison:


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Microwave Vs Wireline Transport:


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118

PRIVATE AND CONFIDENTIAL 2013 CommScope, Inc

1. Wireline is Leased Line

Microwave - Low monthly operating cost

More economical over the long term

Wireline - Lease expenses

2. Microwave Radio Equipment costs are decreasing

3. Microwave installations are becoming simpler

4. Wireless carriers own and control microwave radio network Vs relying on other service providers for network components

Microwave Backhaul Capacity:


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More than half of the LTE networks currently deployed in the worlduse microwave in their backhaul.

According to the Next Generation Mobile Networks (NGMN) alliance,a typical LTE macro tail site (also known as TriCell as it covers 3sectors) requires about 135 Mbps downstream capacity.

If we will consider an extreme scenario of a microwave link thataggregates as much as 20 tail sites, we will receive a backhaul

requirement of 1.5Gbps for LTE networks

Common Bands:


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Common Bands (1)


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11/14 GHz Ku band Satellites

11 GHz Band: 10.7-11.7 GHz: very popular p2p MW band

13 GHz Band: 12.7- ~13.25: new p2p MW band

18 GHz Band: 17.7-19.7: new popular p2p MW band

20/30 GHz: Ka band Satellites 23 GHz: 21.223.6 GHz now widely used for p2p MW

38 GHz: 37.040.0 GHz some licensing for short p2p MW

44 GHz: Q band Satellites, Military use

60 GHz: unlicensed usage 80 GHz: 7176/8186/9295 GHz: E band: just opened.


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Cell Site Design and Components:

Co-Siting Techniques

What is Co-siting?


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Any technique which can help maintain minimum

number of feeder lines, jumper cables and/or cell-site equipments at the cell site (to reduce theCapEx), without jeopardizing the performanceand capacity of the cell-site AND withouthindering the cell-site growth is called Co-siting.

Always ask the question: What component can Iadd and/or remove to get the same or added

functionality at the cell-site?

What is a TMA?


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A Bandpass Filter and Low Noise Amplifier(LNA) mounted near the receiving antenna

Can be easily retrofitted on existing sites

The best solution for improving uplinkperformance

Maximizes service at minimum cost

Compatible with all air interface standards

Functional Diagram of a TMA:


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What do we mean by Compatible

with all air interface standards?


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Crossband Coupler: (CBC Or Dipelxers)


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A diplexeris a passive device that implements frequency domainmultiplexing.

It is a three port device.

Two ports (e.g. Low and High) are multiplexed onto a third port (e.g.,Common). The signals on ports Low and High occupy disjointfrequency bands.

E.g. LowCellular (850 MHz) and HighPCS (1900 MHz)

The signals on Low and High ports can coexist on Common port withoutinterfering with each other.

Crossband Coupler: (CBC Or Dipelxers)


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Key requirements for Diplexers:

Should have high performance bandpass filters

Should provide extremely low insertion loss

Should provide high isolation

Should be able to handle high power

Should be compact and rugged

Weatherproof housing

The diplexer is reciprocal:

the device itself doesn't have a notion of input or output.

Used in pairs


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Plumbing diagram showinguse of Diplexer- Notice the pairs


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Possible configurations forBTS/NodeB/eNB


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Separate Tx and Rx

Tx/Rx ports combined

Two Tx Ports for morecarriers/channels

More than two Tx Ports formore carriers/channels (stilltwo Rx Ports)

Two Tx Ports for morecarriers/channels- Each with its own Rx pair

Why two Rx lines?


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Concept of Space Diversity:

Signal transmitted by a mobile phone is reflected in thepropagation field and reaches the base station takingdifferent paths and phase angle.

If two receiving antennas are separated horizontallyfrom each other, then it is highly likely that one of themwill provide better signal strength (principle ofuncorrelated signals).

Use of Space Diversity provides a diversity gain of 3 to 5dB, as compared to using only one single receivingantenna.

Why two Rx lines?


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Space Diversity - Three Antennas,Three Feeders-Higher number of Antennas-Higher number of Feeder-Increased Space Requirements

-Greater mechanical hardware on tower, undesirable-Approval from Property owners and other authorities

Alternate Solution-Two Antennas- Three feeder lines- What diversity is used here?

- Polarization

Duplexed Vs Simplexed:


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Tx

???

RxTx

Rx2Rx1 Rx2Tx/Rx1

Hatch Plate

DuplexedLine

SimplexedLine

SimplexedLines

Duplexer


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A duplexeris a device that allows bi-directional (duplex)communication over a single channel.

A duplexer is a device which allows a transmitter operating on onefrequency and a receiver operating on a different frequency to shareone common antenna with a minimum of interaction and degradationof the different RF signals.

Duplexer


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Duplexer

Contains filters Combines the transmit and receive paths into a common output.

Is used to interface with simplexed BTS ports

Increases Transmission Efficiency

Isolates the receiver from the transmitter while permitting them to

share a common antenna.

How many ports on Duplexer?

Datasheet for Duplexer


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DIN-f

DIN-f SMA-f

What is different here?


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Duplexer Vs Diplexer:


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Everyone is clear on what a filter is, but there exists some confusion over

what is the difference between a duplexer and a diplexer. a lot of opinions - even between manufacturers.

A duplexer allows simultaneous transmitter and receiver operation in asingle antenna system.

The duplexer isolates the receiver from the transmitter and reduces Tx noise.

By comparison, a diplexer is a device that permits parallel feeding of oneantenna from two transmitters at different frequencies, without thetransmitters interfering with each other.

The duplexer separates 2 frequencies within the same band, while thediplexer separates 2 different bands.

Can you combine more than two bands?


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A diplexer multiplexes two ports onto one port, but more than twoports may be multiplexed:

a three-port to one-port multiplexer is known as a triplexer.


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Plumbing diagram showinguse of Triplexer-Notice the pairs-Notice the antenna type

How many feeders would you needwithout the Triplexers?

Antennas:

P


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Parameters: Gain, Radiation Pattern and Frequency Band

Beamwidth and Aperture Azimuths and Elevation

TiltElectrical and Mechanical

What is an Antenna?


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Antennas transform one form of waves (Wire

Propagated) into another (Space Propagated). Rx Antenna:

receives electromagnetic waves and pass them onto areceiver

Tx Antenna:

transmits electromagnetic waves which have beenproduced by a transmitter.

Connections of an Antenna:


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From a connection point of view, an antenna appears to have dualgate.

In reality it is a quad gate.

One connection is to RF-cable.

The other connection is to the environment.

The surroundings of the antenna have a strong influence on theantennas electrical properties.

Principle of an Antenna:


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Principle of an antenna can easily be shown by

bending a co-axial cable open :A transmitter sends a high frequency wave into a co-

axial cable. A pulsing electrical field is createdbetween the wires, which cannot free itself from the

cable.

If th d f th bl i b t th fi ld li b l d

Principle of an Antenna: Continued.


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If the end of the cable is bent open, the field lines become longer andare orthogonal to the wires.

If h bl i b i h l h fi ld li



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If the cable is bent open at right angles, the field lines

have now reached a length, which allows the wave tofree itself from the cable.

Th d i di t l t ti h b th l th f



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The device radiates an electromagnetic wave, whereby the length ofthe two bent pieces of wire corresponds to half of the wave length.

This simplified explanation describes the basic principle of -dipole.

Antenna Gain:

I h A lifi ?


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Is there any Amplifier?

In reality, no amplification of energy via antennagain.

Antenna Gain

Is defined as the ratio of the radiation intensity of an antenna in a given direction to

the intensity that would be produced by a hypothetical idealantenna that radiates equally in all directions (isotropically)and has no losses.

Antenna Gain:.Continued

A t ith t i di t i di ti


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An antenna without gain radiates energy in every direction.

An antenna with gain concentrates the energy in a defined anglesegment of 3-dimensional space.

Antenna Gain:.Continued

The dipole is used as a reference for defining gain


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The -dipole is used as a reference for defining gain.At higher frequencies the gain is often defined with

reference to the isotropic radiator.

Gain (with reference to the isotropic radiator dBi) = Gain(with reference to -Dipole dBd) + 2.14 dB

The gain of an antenna is linked to the radiationcharacteristic of the antenna.

EIRP: Effective Isotropic Radiated Power

Radiation Pattern:


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Omni-directional Pattern Gain:


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This figure illustrates how stacking four dipoles vertically in linechanges the pattern shape (squashes the doughnut) and increasesthe gain over a single dipole.

The area of the horizontal pattern measures the gain.

Most common and

most popular type of

base station gain

antenna

- Collinear (Vertical)

Phased Array

Radiation Pattern:

In a two way mobile communication we really arent concerned about


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In a two way mobile communication, we really aren t concerned about

the antennas vertical pattern. In the field, we are looking at horizon

elevations. E.g. for a 200 feet tall tower on a hill that is 200 feet high, total

antenna height is 400 feet.

At a distance of 20 miles, the angle between the base station and themobile unit would be less than 1 degree.

Radiation Pattern and Gain:

Antenna gain and pattern shape are interrelated: if one is changed


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Antenna gain and pattern shape are interrelated: if one is changed,the other will be affected.

By changing the radiation pattern, we are changing the focus ofantenna, i.e. directivity of the antenna.

Aperture:

As the aperture or opening size of a valve controls the amount of


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As the aperture or opening size of a valve controls the amount ofwater that flows through a pipe, the aperture or beamwidth

determines the gain of the antenna. The effective aperture actually takes in something more than the

physical size. We think of the aperture as the signal surrounding theantenna in all directions and extending out a given distance from thesides and ends.

The aperture is a volume of space.

Effectiveness can be measured through Beamwidth. As an example, a smaller aperture or beamwidth, say 65 degrees, will have a

greater gain than a larger aperture, say 90 degrees.

Beam Width:


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Beamwidth is the angle between the half-power (-3 dB) points of themain lobe, when referenced to the peak effective radiated power of themain lobe.

-Usually expressed in degrees.-Usually expressed for the horizontal plane

The radiation pattern in the smaller beam width is

Beam Width:


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The radiation pattern in the smaller beam width isprojected farther forward along the horizontal plane andless along the vertical plane; this results in a higher gain.

Conversely, the radiation pattern in the larger beam widthhas more of the signal projected along the vertical planeand less along the horizontal plane; this results in a lowergain.

Azimuth Vs Elevation:


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Why two Rx lines?


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Space Diversity - Three Antennas,Three Feeders-Higher number of Antennas-Higher number of Feeder-Increased Space Requirements

-Greater mechanical hardware on tower, undesirable-Approval from Property owners and other authorities

Alternate Solution-Two Antennas- Three feeder lines- What diversity is used here?

- Polarization

Space Diversity: is any one of several wireless diversity schemes



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Space Diversity: is any one of several wireless diversity schemesthat use two or more antennas

to improve the quality and reliability of a wireless link.

Often used in urban and indoor environments as there is not a clearline-of-sight (LOS) between transmitter and receiver.

Antenna diversity is used to mitigate the multipath situations.

Each antenna will experience a different interference environment. If one antenna is getting a faded signal, it is likely that another

has a sufficient signal.

Signal transmitted by a mobile phone is reflected in the



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Signal transmitted by a mobile phone is reflected in thepropagation field and reaches the base station takingdifferent paths and phase angle.

If two receiving antennas are separated horizontally fromeach other, then it is highly likely that one of them willprovide better signal strength (principle of uncorrelatedsignals).

Use of Space Diversity provides a diversity gain of 3 to 5dB, as compared to using only one single receivingantenna.



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Each antenna showing VerticalPolarizationOne port for each antenna# of antennas = # of feeder lines

Polarization diversity is completely effective only in high multipath

Concept of Polarization Diversity:


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Polarization diversity is completely effective only in high multipathenvironments.

Use of Horizontal and Vertical Polarity of received signal

Orthogonal polarizations:

You can improve uplink performance by using two receiveantennas with orthogonal polarizations and combining thesesignals.

Two receive antennas do not need to be spaced aparthorizontally to accomplish this.

Can be mounted under the same housing.

A dual-polarized antenna is an antenna-device with two arrays within



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A dual polarized antenna is an antenna device with two arrays withinthe same physical unit.

The two arrays can be designed and oriented in different ways aslong as the two polarization planes have equal performance withrespect to gain and radiation patterns.



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Each antenna showing DualPolarizationTwo ports for each antenna# of antennas # of feeder lines

Possible configuration on two ports:Port 1 Port 2Rx1 Rx2Tx/Rx1 Rx2Tx1/Rx1 Tx2/Rx2Rx1 Tx/Rx2



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The two arrays can be used ascombined TX/RX antennas andthen the number of antenna unitsis reduced compared with spacediversity.

Typical Examples of Base StationAntennas:


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Dual port antenna:-What Diversity?

- Space Diversity (Single Polarization)- Single-band or Dual-band Antenna?- How many technologies per sector?- How many antennas per sector?

-Two antennas per sector

Dual port antenna:- Polarization Diversity- Single-band or Dual-band

Antenna?- How many technologies persector?- How many antennas persector?

Dual port antenna:- Polarization Diversity

- Single-band Antenna-One technology per sector- How many antenna persector?

Typical Examples of Base StationAntennas:


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Quad antennas (four ports)

Quad port antenna:

- Polarization Diversity- Single-band or Dual-band Antenna?- How many technologies per sector?- How many antennas per sector?


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Network Optimization:


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1) By Selecting Frequency Hopping2) By Selecting number of carriers

(Channels) per sectors for capacity

3) Selecting coverage area(foot-print) for the cell-site

a) By Changing the Azimuthb) By Providing Beam-tilting

- Mechanical Tilt

- Electrical Tilt

Why optimize?

To reduce dropped calls


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pp

To reduce interference from adjacent sites

Closes gaps in coverage

To increase throughput and capacity

Mandatory when building new sites

Smooth hand-overs

Azimuth Vs Tilt:

Azimuth and Tilt of Antenna during Installation


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Accuracy depends on:

Installation process

Human and Instrumentation Errors

Azimuth Set-up:

Using Compass and alignment tool

Azimuth Error:

Azimuth Error:


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Is the absolute difference between actual azimuth installed

and designed azimuthAlways Positive

0 degree

240 degree

120 degree

Tilt Error:

Tilt Error:


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Uptilt errors areve

Downtilt errors are +ve

More crucial than

Azimuth Errors

What is Beam-tilting?


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Its a technique to direct maximum radiationpower towards an area below horizon.

Why?

Provides more coverage to the areas near BaseStation.

More penetration of RF energy

to nearby buildings

and high density garages. Low interference with

adjacent frequencies

Beam Width:


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Beamwidth is the angle between the half-power (-3 dB) points of themain lobe, when referenced to the peak effective radiated power of the

main lobe.

-Usually expressed in degrees.-Usually expressed for the horizontal plane

Four Considerations for Beam-tilting:

1) Needs to be done often to adjust network configuration in


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accordance with subscriber movements

2) Needs to be done quicklynot necessarily in maintenancewindow

3) Preferableif done remotely

4) Needs to be done accurately

Beam Tilting for optimized coverage:

Nearly 30 % of network optimization can be achieved with


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beam-tilting.

Nearly 40% of sites are out of specification from originalrequirements on antenna angles

Tower climb can cost ~ $ 3,500$ 4,000

Roof-top site climb ~ $ 1,000$ 1,500

Frequent changes to tilt translate to frequent site visitstime consuming and expensive

Manual tilting can be inaccurate, more delays andexpensive

The Old Way: Mechanical Tilting

F t fi ti h d


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For every antenna configuration change, someone needs:

to drive out to the site. to climb the tower or rooftop.

to tilt the antenna mechanically.

Site access is a major concern for many sites.

Expensive. Time consuming and weather dependent.

Long delay until the complete optimized RF

plan is actually implemented.

Coverage gaps until all sites are optimized.

Number of optimization changes reduced

to minimum in order to save costs.

The New Way: Electrical Tilting


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For every antenna configuration change:

No one needs to drive out to the site.

No one needs to climb the tower or rooftop.

The antenna does not need to be moved.

No site access issues or paperwork.

Convenient modifications made from the office. Independent from bad weather.

Full network visibility.

Almost no running costs.

Quick and immediate real-time execution. Optimization changes can be scheduled and executed several

times a day.

Mechanical Vs Electrical Tilt:


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Front lobe peak tilts below horizonBack lobe tilts above horizonUseful tilt only at beam-peak

Front lobe peak tilts below horizonBack lobe also tilts below horizonEntire pattern tilts, not just front lobe

Typical Antenna Pattern: Horizontal


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Benefits of Electrical Tilt:

Pattern tilt is achieved all around the site and not only in the front (likeM h i l Tilt)


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Mechanical Tilt).

Pattern style remains stable. Higher values of tilt is possible.

AISG Compliance

AISGAntenna Interface Standards Group.

F d 2001 b t t OEM


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Formed 2001 between operators, OEMs,

and equipment suppliers. Mission was to create an open specification

for the data interface for base stationantennas.

Expanded to include tower mounted

amplifiers and other tower top devices. CommScope has products in compliance

with the AISG standards.

Web site: www.aisg.org.uk

CommScope RET controller fully supportsAISG 1.1 and 2.0

Two AISG Versions:

AISG 1.1

AISG 2.0

Actuators:


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Attached Below Antenna. In-built motor and other mechanism provides

electrical tilt to Antenna. Two connectors for ease in daisy-chaining. Up to 32 actuators can be supported

in a daisy-chain. AISG standards 1.1 and 2.0 The actuator is equipped with a flashing LED

which indicates data transfer and tilt movements. It comes in a weather resistant gasket-sealed

container that has a drain hole to permit drainageof condensed moisture.

CommScopescontroller hardware


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AISG Signal:

Th t ll id 8 i i l f l RET AISG


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The controller provides an 8-pin circular female RET AISG

connector port. This port is used to connect the controllerto a RET system using AISG RET cabling.

Three Basic Configurations:


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Three Basic Configurations: Home-Run Cable Configuration

Smart Bias Tee Configuration

Smart Bias Tee and TMA Configuration

RET system always include:

RET Controller

AISG Control Cable Actuators

1) Home-Run Cable Configuration:

RET Controller is connected to Actuators via dedicated AISG controlcable


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cable

Multiple actuators can be joined via Daisy-chaining or by usingJunction Box.

Electrical tilt adjustments can be made remotely from the BTS using aportable or rack mount controller or over a network using a rackmount controller.
http://www.commscope.com/andrew/eng/product/antennas/teletilt/systems/1214411_17177.html


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Home Run CableConfiguration:

2) And 3) Smart Bias Tee and TMAConfiguration:

To reduce the number of cable runs leading to a tower,AISG can be injected on existing RF Feeder line via


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AISG can be injected on existing RF Feeder line via

Smart Bias Tee.

On tower side, another Smart Bias Tee can be used torestore the control signal back on AISG control cables

going to actuators.

If a TMA is required on Rx Lines, a Smart TMAs (TMAwith AISG capability) can also be used to inject the signalback on control cables.


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Smart Bias Tee andTMA Configuration:

RET Video:

http://www.commscope.com/andrew/eng/product/antennas/teletilt/index.html
http://www.commscope.com/andrew/eng/product/antennas/teletilt/index.htmlhttp://www.commscope.com/andrew/eng/product/antennas/teletilt/index.html


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SmartBeamAntenna Systems

SmartBeam antenna systems enhance optimization options and execution.

SmartBeam antenna systems allow load balancing.


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1-Way SmartBeam (1D)

Remote Electrical Tilt (e.g. 010)

2-Way SmartBeam (2D):

Remote Electrical Tilt (e.g. 010)

Remote AZ Steering (+/30

)

3-Way SmartBeam (3D):

Remote Electrical Tilt (e.g. 210

)

Remote AZ Steering (+/30

) Remote AZ Beamwidth (35 to

105)

Tilt

Tilt

Tilt Pan

Pan

Fan


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RF Measurements at a Cell Site:

Insertion Loss:

The loss in power due to the insertion of acomponent or device in a transmission system


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component or device in a transmission system.

Expressed as the ratio in decibels (dB) of thepower received at the load before insertion ofthe component, to the power received at theload after insertion.

Connector Loss, Line (Cable) Loss

Return Loss:

is a measure of power reflected from imperfections in a transmissionline


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line.

It is the ratio PR/ PT, representing the power of the wave reflectedfrom the imperfection (PR) to that of the incident wave, (PT).

Return Loss Concept:


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Glass

TransmittedLightIncidentLight

Transmission

Line

Reflected

Light

ReflectedWave

Transmitted

Wave

Incident

Wave

Imperfectionin

Transmission

Line

For best performance the reflected signal should be as small as

Return Loss:


202/291


For best performance, the reflected signal should be as small as

possible, meaning the ratio PR/ PTshould be as small as possible. It is the reduction in the amplitude of the reflected energy, as

compared to the forward energy.

Expressed in dB.

-3 dB o