2. OMF000004 RF parts and Antenna ISSUE2.0

8/7/2019 2. OMF000004 RF parts and Antenna ISSUE2.0

1/55

HUAWEI TECHNOLOGIES CO., LTD. All rights reserved

www.huawei.com

Internal

OMF 000004Radio Frequency Part and

Antenna

ISSUE 2.0


2/55

HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 1

RF components are widely used in

wireless system, and effectperformance of network


3/55


Upon completion this course, you will be able to:

>Understand the structure and features of

combination unit

>Master the key specifications of antenna

>Be able to choose the suitable type of RF

component


4/55


Chapter 1Chapter 1 RF Part in BTSRF Part in BTS

Chapter 2Chapter 2 AntennaAntenna

Chapter 3Chapter 3 Feeder and TTAFeeder and TTA


5/55


RF Device of BTS

A te a

TTA

A te asta d

J er et eea te a a d TTA

J er et eeTTA a d feeder

Feeder

Lighte i g

arrester

J

er et eelighte i g arrestera d ca i et

BTSca i et

SWI

CH

OX

N OX

I OX

P

S

U

P

S

U

P

S

U

P

S

U

P

S

U

P

S

U

P

U

T

U

T

E

S

T

E

U

T

E

U

C

D

U

C

D

U

X

X

X

X

C

DU

C

D

U

X

X

X

X

C

D

U

C

D

U

DU

N OX

I OX

P

S

U

P

S

U

P

S

U

P

S

U

P

S

U

P

S

U

P

U

X

X

X

X


6/55


Introduction

RF device in BTS includes two parts

Indoor: combiner and splitter unit

For example: CDU module, SCU module and EDU module

Outdoor: antenna, feeder, TTA (tower top amplifier), jumper andlightning arrester


7/55


Function of Combiner and Divider

Use one antenna to support multiple TX/RX

signals, decreases the amount of antenna and

feeder

Complete duplexer of TX/RX and combine TXsignal filter, amplify and split the RX signal

Provide power for TTA


8/55


CDU (Combining and Divider Unit)

Tx1

Tx2

Tx_CombTx_Dup

combiner duplexer

divider

divider

amplifier

filter

Rx1Rx2Rx3Rx4

Rx5Rx6Rx7Rx8

HL_out

HL_in

RxD_outRxD

Tx/Rx_ANT


9/55


SCU (Simple Combiner Unit)

TX1

TX2

TX3

TX4

TX -Comb

combiner

combiner

combiner


10/55


EDU (Enhance Duplexer Unit)

Tx1 duplexer

divider

amplifier

Rx1

Rx2

Tx/Rx_ANT1

divider

amplifier

Rx1

Rx2

duplexer Tx/Rx_ANT2Tx2


11/55


Comparison among Different Combining Units

combine

mode

typical loss

value of

T (dB)

price

comparison

(per TR )

CDU

combine twoTX signal

one step 3dBcombiner

4.5 middle

SCUcombine four

TX signaltwo step 3dB

combiner

6.8 low

SCU+CDU

combine fourTX signal

two step 3dBcombiner

8 low

EDU no combinerdouble duplex 1 middle

Double CDU( with combiner)

no combinerdouble duplex

1 high

Double CDU(without combiner)

combine twoTX signal

double duplex4.5 middle


12/55


New Type CDU&ESCU

ECDU

> The structure is the same as CDU's, but increase MAX. input

power. It can bear up to100W input RF power

ESCU

> The structure is the same as CDU's, but increase MAX. input

power. It can bear up to100W input RF power


13/55


Chapter 1Chapter 1 RF Part in BTSRF Part in BTS

Chapter 2Chapter 2 AntennaAntenna

Chapter 3Chapter 3 Feeder and TTAFeeder and TTA


14/55


What is Antenna?

Radiate and receive radio wave ,convert high frequency current

to electromagnetic wave when transmitting, and convert

electromagnetic wave to high frequency current when receiving

B l a h blahb la h b l a h


15/55


Classification

Classify by working band: UHF, VHF, microwave, etc.

Classify by radiate pattern: omni, directional

Classify by structure: line, pane, parabola feed

Classify by polarization: vertical and horizontal Classify by outline: line and pane


16/55


omni directiondirectional Antenna

Radiate Pattern


17/55


Outline


18/55


vertical polarizationOmni antenna

dual polarizationdirectional antenna

Polarization

vertical polarizationdirectional antenna


19/55


Function

Convert high frequency current to electromagnetic wave when

transmitting

Convert electromagnetic wave to high frequency current when

receiving

Antenna can not amplify the transmission power, just concentrate

RF power to one direction

horizontal section Vertical section


20/55


Radiate Pattern

Omni antenna

lobe

Direction

antenna lobe


21/55


Radiate pattern


22/55


Dipole and Isotropic

Dipole

1/4 wave length

1/4wave length

1/2wave length

Isotropic

Ideal radiator with same ability on all direction!


23/55


Gain

The radiation ability of certain antenna overtop dipole or isotropic

Indicates the antenna feature of electromagnetic radiation in specific

directions

Unit: dBi/dBd

theory source

l/2 antenna

Direction antenna

dBd

dBi

dBi = dBd+2.15


24/55


Forward to Back Ratio

The ratio of main lobe signal strength to back lobe

This value is within 1845dB. In urban, it is suggested to use

the antenna with high F/B ratio


25/55


Beam Angle

HPBW: Half Power Beam Bandwidth

Lobe angel between two points, the power of which reduce to

the half of that of the maximum radiate direction

Vertical HPBW and Horizontal HPBW

60 (eg) Peak

- 3dB

- 3dB

15 (eg) Peak

Peak - 3dB

Peak - 3dB


26/55


Down title

To control coverage

To decrease inter modulation

Realization: electron and mechanism


27/55


mechanism

electron

Down tilt


28/55


Effect of Electron Down title

No Down tilt Electron Down tilt


29/55


Effect of Mechanism Down tilt

No Down tilt Electron Down tilt


30/55


Effect of different methods

10(E) 10(M)6(E)+ 4(M)


31/55


Polarization

The direction of electro - vector radiated by antenna. The

vertical polarization wave is vertical with the plane of ground,

and the horizontal polarization waves parallel with the plane of

ground

Single antenna has only one polarization direction.

Dual polarized antenna contains two single - polarized antenna

in one entity. Dual polarization antenna usually adopts +45/-45

degree orthogonal polarization.

-


32/55


Polarization

VERTICAL RIZ TAL

+ 45 - 45


33/55


Dual Polarization

V/ +/- 45


34/55


Port Isolation

The isolation among ports should be more than 30 dB. for multi-portsantenna, Such as dual band, dual polarization antenna

1000mW (1W) 1mW

10log(1000mW/1mW) = 30dB


35/55


Null Filled

It shall apply null filled technology when zero depth is less

than main beam for 26dB.

High gain antenna especially adopt null filled technology to

effectively improve the nearby coverage


36/55


Main to lowerside

Main to upperside

Upper Side Lobe Suppression


37/55


Coupling Between Antennas

main lobe

5 .. 10P

Horizontal separation

> Sufficient decoupling distance: 5-10

> Antenna patterns become superimposed if

distance is too close

Vertical separation

> Decoupling distance:1 can provide better RX

/TX decoupling

Minimum coupling loss


38/55


Installation Examples Recommended decoupling

> TX - TX: ~30dB

> TX - RX: ~40dB

Horizontal decoupling distance

depends on> Antenna gain

> Horizontal rad. pattern

Omni-directional antenna

> Use vertical separation for RX and

TX

> Use vertical separation (fork) for

RX and diversity RXVertical decoupling is much more effective

0,2m

Omni-directional.: 5 .. 20mdirectional : 1 ... 3m


39/55


Antenna Installation

Coupling loss (dB):

Lv=28+40log(k/) (vertical installation)

Lv=22+20log(d/)-(G1+G2)-(S1+S2) (horizontal installation)

: wave length

K: distance at vertical

D: distance at horizontal

G1G2: gain

S1S2: Relative gain at line connected two antenna


40/55


Distributed Antenna System

BTSBTSPowersplitterPowersplitter

Powersplitter

coupling

coupling

coupling

coupling

Small

antenna

Smallantenna

Smallantenna

Small

antenna

Smallantenna

Smallantenna

Smallantenna

coupling

Dual direction

amplifier

Dual direction amplifier


41/55


Symmetry and Asymmetry Network

Tx/Rx

3

3

3

3

3

3

3

3

3

3

3

Tx/Rx

1.36

0.510

100.5


Dual direction

amplifier


42/55


Optical Fiber Distributed Antenna

The optical fiber repeater is mainly adopted in the case

of wide coverage and long distance transmission

signal

Optical transceiver

Optical transceiver

transceiver

transceiver


43/55


Leaky Cable

Coaxial cable with perforated leads

It is mainly adopted for tunnel, metro and with high cost of

equipment and installing

Tx/Rx

Matching load

Matching load



Power splitter


44/55


Leaky cable

Coaxial cable with perforated leads

Produce constant field-strength along cable runs

Work at wide-band

Radiating loss become higher with high frequency

Very large bending radius

Formerly often used for tunnel coverage

Expensive


45/55


Feature of Leaky Cable

Transmission loss per hundred meter

Typical value : 10~40 dB per 100m

Couple Loss at 1 meter distance

Typical value 55 dB (at 1m)

How to calculate strength with leaky cable?


46/55


Comparison with Distributed Antenna

type leaking fiber coaxial fiber optical

design agility good good not good

cost high low highComplexity of

installinghigh low low

loss oftransmission

high high low

power supply not needed not needed needed

reliability high high low

applicability metro, tunnelhigh building,commercial

area

far areacoverage


47/55


Chapter 1 RF Part in BTSChapter 1 RF Part in BTS

Chapter 2 AntennaChapter 2 Antenna

Chapter 3 Feeder and TTAChapter 3 Feeder and TTA


48/55


Tower Top Amplifier

Amplify uplink weak signal, then:

Balance uplink and downlink

Compensate loss of feeder

Simplex TTA duplex TTA triplex TTA


49/55


Triplex Tower Top Amplifier

Low noise amplifier

TX filter

bypassBias Tee

BTS

triplex TTA

antenna

DC

RX filterRX filter


50/55


Data Configuration of CDU Turn on power of TTA in CDU before installation> TTA switch is in rear panel of CDU

Configuration alarm threshold of TTA current before installation

> TTA current switch is in rear panel of CDU

Configuration attenuation factor of receive signal on consol

> attenuation factor of receive signal

=TTA gain feeder loss

Simplex TTA gain:14dB, triplex TTA gain:12dB

Don t use TTA if not necessary

> For the convenience of installation

> To get better lighting -proof effect


51/55


Power Switch and Current Limit

Rear panel of KMW CDU

TTAM TTAD

OFF OFF

TTAM TTAD

123TTAM TTAD

OFF OFF

123

TTAM: power switch of main TTA switch

TTAD: power switch of diversity TTA

select current limitTTAM TTAD


52/55


Power Switch and Current Limit

0 1 2 3

012

3

Note:

MAINmain TTA switchDIVERSEdiversity TTA switch

Rear panel of COM DEV CDU

01 2

3

012

3

01 2

3

012

3


53/55


Feeder Feeder selection

> Type : 1/27/85/4

> Select 5/4 in the case of feeder length is more than 80 m

> and otherwise select 7/8 in 900MHz

> Select 5/4 in the case of feeder length is more than 50 m

> and otherwise select 7/8 in 1800MHz

> Feeder curvature should not be so big, outer conductor

> should be connected to earth

LG0.251.156.74.47HFC22D -A(7/8 )

6090.31.156.465.874.03SYFY - 50 - 22(7/8 )

ACOME0.221.156.64.3M1474A(7/8 )

ANDREW0.381.154.774.313.172.98LDF6 - 50(5/4 )

ANDREW0.251.156.465.874.34.03LDF5 - 50A(7/8 )

2,0001,7001,000890manufacturer

BendRadius (m)VSWR

LOSS dB/100m (MHz)TYPE


54/55


In this course, we have learned:

CDU structure and loss SCU structure and loss

Antenna type and feature

TTA

SummarySummary


55/55

www.huawei.com

Thank You

2. OMF000004 RF parts and Antenna ISSUE2.0

Documents

Transcript of 2. OMF000004 RF parts and Antenna ISSUE2.0