SECTION 4 - RF System Design.ppt

7/24/2019 SECTION 4 - RF System Design.ppt

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ESTeem RF Design Tools



Presentation Overview

• Review Radio Basics

– Terminology

•

Use Information from Radio Basics and AntennaSections

• Use RF Design Program

–

Initial Site Work– Using RF Design Program

– Site !am"le




• ac# Radio A""lication is Uni$%e

– Wireless is &eing a""lied in many a""lications&%t few #ave a working knowledge of designing a

s%ccessf%l wireless system• Selecting A Wireless 'endor

– Di((ying array ranges from vendors

–

Provide tools to "ersonally review s"ecifications



Ste"s to S%ccessf%l Radio )etwork

• RF System Design

– Review *a"s

– RF Design Program Analysis

• On+Site Radio Site S%rvey

– P#ysical Ins"ection and Testing

– ,onfirming Res%lts from RF System Design

• Site ,ommissioning

– Same Testing on Installed System




• RF Design Program

– ,onservative model of e!"ected radio res%lts-• Installed #ardware generally #ig#er signal strengt#s

– Allows for modification to system design "rior toinstallation if "ro&lems are fo%nd• ,#ange Antenna Ty"e

• ,#ange ,oa! ,a&le Ty"es

– Provides means of determining e!"ected dataerrors



Earth

Antenna A Antenna B

Minimum

Height (ft.)Minimum

Height (ft.)

Distance (miles)

Radio Horizon

Directional

Antenna

mni!directional

Antenna

Bottom Reference "ine

for Height #learance

*inim%m Antenna .eig#t Re$%iredto ,lear t#e Radio .ori(on



• Fresnel /one s#ows t#e elli"soid s"read of t#e radio waves

• Area m%st &e clear of o&str%ctions or signal strengt# will &e red%ced

• Blockage in 012 will ind%ce significant signal losses

• Use for fre$%encies a&ove 311 *.(

Fresnel /one



RF Basics + ffective Radiated Power

• ffective Radiated Power 4RP5 6 T! Power + Feedline 7osses 8

Antenna 9ain

• Received Signal 6 R! Power + Feedline losses 8 Antenna 9ain



RF Basics + Fade *argin

• Receiver Sensitivity is t#e minim%m signal level in dBneeded &y t#e receiver to o%t"%t received data:

• Fade *argin in dB is t#e amo%nt of received signal a&ove t#ereceiver;s minim%m re$%ired %sea&le Receiver Sensitivity:

•

Fade *argin is controlled &y– Transmitter Power

– Transmitter feedline atten%ation

– Transmitting antenna gain

– Receiving antenna gain

– Receiver feedline atten%ation

– Receiver Sensitivity Minimum Recei$er Sensiti$it%

Ma&imum Recei$ed

Signal Strength

Fade Margin ' sale

Range of Recei$er



•

.ow m%c# Fade *argin<– Im"erfect world and t#ings are constantly c#anging:

• $%i"ment ages• Antennas go o%t of alignment•

Une!"ected man+made noise=interference– Basic r%les of t#%m& for digital transceivers:

• >1 dB + >12 link retries• ?1 dB + >2 link retries• @1 dB + :>2 link retries

– 7ink 7isted *arginal >1dB• Over >1dB Fade *argin 6 9reen• >+>1d& Fade *argin 6 ellow 4*arginal5• 7ess t#an >dB 6 Red 4Site )ot O"erational5

RF Basics + Fade *argin



• Draw a sim"le layo%t of t#e "ro"osed system:• Determine 7ine+of+Sig#t 47OS5 distances

&etween eac# "oint to "oint radio "at# &yC

– Site ma"s:– If 7atit%de and longit%de are known %se t#e

Distance Between Two Points ,alc%latorE in t#eRF Design Program:

– Use a #and #eld 9PS:

– 9oogle art#

Initial Site Work



• *ost Radio Systems are designed as a*%lti"leE of Point to Point RF Pat#s

– Base to Remote

– Base to Re"eater

– Re"eater to Remote

– Re"eater to Re"eater

• ac# Pat# )eeds val%ation

Initial Site Work



• Sketc# a site diagram and distances &etween site nodes:)ote 7OS &lockages:

N

*um+ Site ,-

#ontrol Room

*um+ Site ,

/ater Tan0

*um+ Site ,1

" S

"S" S

" S

2 m i l e s

3 . 3

m i l e

s

3 m i l e s

1 miles

"S"S

Initial Site Work



• Find t#e elevation of eac# node a&ove sealevel:– Reference ma"s or %se a #and #eld 9PS:

– 9oogle art#• stimate installed antenna #eig#t at eac#

node a&ove gro%nd level to ac#ieve 7OS todestination site:

• stimate feedline lengt# from antenna toe$%i"ment ca&inet:

Initial Site Work



Antenna

Feedline

"ength

E4ui+ment

#ainet

Terrain Height

Ao$e Sea "e$el

Height of Antenna

Ao$e 5round for

"S *ath

Initial Site Work



• ,alc%late Elevation Differential &etween t#e lowestnode and t#e remaining nodes:

•

,alc%lated t#e Adjusted Antenna Height.– Site levation Differential 8 Antenna .eig#t a&ove

gro%nd:

Initial Site Work



6ame Site Ele$. Ele$. Dif. Ant. Hgt. Ad7. Ant. Hgt. Feedline "gh.

Control Room 560 80 20 100 30

Pump Site #1 570 90 20 110 30

Pump Site #2 820 340 20 360 30

Water Tank 1100 620 120 740 130

Pump Site #3 480 0 15 15 30

Site 8nformation

Calulate Elevation

Differential !et"eenlo"et no$e an$

remainin% no$e&

Adjusted Antenna Height '

(le)ation *i++erential ,

-ntenna .ei%/t a!o)e

%roun$&

Initial Site Work



N

*um+ Site ,-

#ontrol Room

*um+ Site ,

/ater Tan0

*um+ Site ,1

2 m i l e s

3 . 3

m i l e

s

3 m i l e s

1 miles

"S"S

Site 7ayo%t *a" and Information



• Use t#e RF Site Design Program on eac#"oint+to+"oint RF "at#:

– In t#is e!am"le we will %se t#e STeem >3Gg

–?:H 9.( Fre$%ency

– Use yo%r Site Information Ta&le data

– Use 'endor information on transceiver selected• T#e RF Site Design Program will "rovide STeem

#ardware recommended for o"erating fre$%encyselected

– nter data in t#e Data ntry ey Board

RF Site Design Program



Standard nclos%re *o%nting

"ightningArrestor

- n t e n n a P o r t

( 0 u i p m e n t P o r t

Directional

Antennas

mni!Directional

Antenna

#oa& #aleESTeem

Model 93Eg

*o:er Su++l%



*odel >3G O%tdoor Pole *o%nt

Model 93Eg

mni!Directional AntennaModel 93E utdoorFi&ed Base Hard:are

Diagram

Direct *ole Mount

*ole Mounting ;it(ST PN --195P

*o:er $er

Ethernet #ale(t/ernet C-T5e Ca!le 300 +t& maimum

/eather *roof Boot

/eather *roof Front

#o$er

Antenna Feedline

E&ternal Antennas

Directional

Antennas

/eather *roofBoot

/eather *roof Boot

To "A6

8nterface

*oE *o:er Su++l%

(ST PN --175

Ethernet Surge

*rotection(ST PN --166

(t/ernet

C-T 5e Ca!le

(ST PN --09&2

nit S/o"n Wit/ Ru!!er *ut -ntenna

Direct Mount Antennas



O%tdoor *o%nting Benefits

• Remove 7ong ,oa! ,a&le Re$%ired– 7ower cost 4J0G+JG11 Savings5

– 7ower signal loss

•

)o 7ig#tning Arrestor )eeded– 7ower cost 4J>?1 Savings5

– Also removes loss in K%m"er ca&le

•

)o nclos%re )eeded– 9reatly red%ced design and installation costs 4J@11

Savings5



N

*um+ Site ,-

#ontrol

Room

/ater Tan0

*um+ Site ,1

2 m i l e s

3 . 3

m i l e

s

3 m i l e s

1 miles

"S"S

*erform a RF *ath Anal%sis from the #ontrol

Room to *um+ Site ,.

6ame Ad7. Ant. Hgt. Feedline "gh. Ant. T%+e

#ontrol Room << 1< mni!Dir.

*um+ Site , < 1< Direction

*um+ Site ,

RF Pat# Analysis,ontrol Room to P%m" Site L>

# l i




#ontrol Room << 1< mni!Dir.

*um+ Site , < 1< Direction

*ath Distance= 2 miles


# l i



> 8n this e&am+le :e used the highest R& Sensiti$it% of !?9 dB for a RF data rate

of M+s. This :ill gi$e a -.@ dB Fade Margin for a 2 mile +ath length.

> /hat :ould e the ma&imum data rate for this RF lin0




RF O%t"%t Power 7evels

• Peak Power vs Average Power– Based %"on ty"e of mod%lation ty"e

– *a!im%m for "eak "ower set &y F,,=DO,

• *od%lation– Average "ower and "eak same in Direct Se$%ence

– *a!im%m "eaks in OFD* #as lower average "ower

• Average "ower %sed in RF Design Program– *od%lation ty"e &ased %"on data rate

– 'erify all RF data rates and "ower levels



RF Data Rate Analysis L>

• Only availa&le for wireless t#ernet "rod%cts >3GgM >3G" and >3Gd• nter site information same as RF Pat# Analysis

• Fade margin res%lts for eac# data rate– Over >1dB Fade *argin 6 9reen– >+>1d& Fade *argin 6 ellow 4*arginal5– 7ess t#an >dB Fade *argin 6 Red 4Site )ot O"erational5



RF Data Rate Analysis L>

• *a!im%m design data rate for a""lication wo%ld &e 3 *&"s• *a!im%m "ossi&le data rate is >N *&"s

• Act%al Data Rates ,o%ld Be .ig#er in )ormal O"eration– >3G will not reserve >1dB in o"eration– >3G will maintain #ig#est data rate "ossi&le



• Same a""lication %sing #ig#er gain directional antenna

• AA?1Hg >3dB Para&olic directional antenna

• 7egal for %se from single remote to omni+directional

RF Data Rate Analysis L?



RF Data Rate Analysis L?

• *%c# #ig#er RF Data Rates availa&le wit# #ig#er fade margin

• *a!im%m design data rate for a""lication wo%ld &e ?H *&"s

• *a!im%m "ossi&le data rate is HN *&"s

RF P t# A l i



N

*um+ Site ,-

#ontrol Room

*um+ Site ,

/ater Tan0

*um+ Site ,1

2 m i l e s

3 . 3 m i l e

s

3 m i l e s

"S"S

*erform a RF *ath Anal%sis from the #ontrol Room to

*um+ Site ,-.

- 2 M ) + s

1 miles

RF Pat# Analysis,ontrol Room to P%m" Site L?

RF P t# A l i





RF Pat# Anal sis





• *a!im%m "ossi&le data rate is @0 *&"s

RF Pat# Analysis




Control Room 100 30 mni*ir&

Water Tank 740 130 mni*ir&

N

*um+ Site ,-

#ontrol Room

*um+ Site ,

*um+ Site ,1

2 m i l e s

3

. 3 m i l e

s

3 m i l e s

"S"S/ater Tan0

1 m i l e s

*erform a RF *ath Anal%sis from the #ontrol Room to /ater Tan0.

- 2 M ) + s- 2 M ) + s

RF Pat# Analysis,ontrol Room to Water Tank

RF Pat# Analysis





Control Room 100 30 mni*ir&

Water Tank 740 130 mni*ir&


RF Pat# Analysis




• *a!im%m design data rate for a""lication wo%ld &e 3 *&"s

• *a!im%m "ossi&le data rate is ?H *&"s



N

*um+ Site ,-

#ontrol Room

*um+ Site ,

*um+ Site ,1


/ater Tan0 B2< 1< mni!Dir.

*um+ Site ,1 3 1< Directional

Site 8nformation

2 m i l e s

3 . 3 m i l e

s

3 m i l e s

"S"S/ater Tan0

1 miles

*erform a RF *ath Anal%sis from the /ater Tan0 to *um+ Site ,1.

- 2 M ) + s - 2 M )

+ s

9 M)+s

Water Tank to P%m" Site L@

RF Pat# Analysis



*ath Distance= 3.3 miles


/ater Tan0 B2< 1< mni!Dir.

*um+ Site ,1 3 1< Directional

Site 8nformation

RF Pat# AnalysisWater Tank to P%m" Site L@

RF Pat# Analysis



RF Pat# AnalysisWater Tank to P%m" Site L@


• *a!im%m "ossi&le data rate is @0 *&"s

Pole *o%nting



• Pro&lem areas– Fresnel Zone Warning

• Increase #eig#t of t#e P%m" Site L@ Antenna – )eed to increase from >G ft: to @@ ft: to &e a&ove t#e minim%m #eig#t re$%irements for t#e

Fresnel /one:

– In t#is e!am"le I increased #eig#t to H1 ft: for a margin of error:

Pole *o%ntingWater Tank to P%m" Site L@



*odel >3Gg *a!im%m Range

•

Two Directional Antennas– AA?1Hg is t#e #ig#est gain antenna t#at t#e %nit is ty"e

acce"ted for:

– >3 dB gain

• ,a&le 7oss

– :0 dB &eca%se t#e %nit is "ole mo%nted:

•

Range– >3 miles > *&"s 0 dB Fade *argin

– N miles GH *&"s 0 dB Fade *argin



•

Range– >3 miles > *&"s 0 dB Fade *argin

• Antenna .eig#t 6 HM1>1 ft at eac# end

• Fresnel /one 40125 6 >NG feet

• This would probably be usable only from mountain topto mountain top

– N miles GH *&"s 0 dB Fade *argin

• Antenna .eig#t 6 GH ft: at eac# end• T#is is a "ractical #eig#t




• Two Omni+Directional Antennas

– AA?1g

– 0 dB gain

• ,a&le 7oss

– :0 dB &eca%se t#e %nit is "ole mo%nted

• Range 0 dB wit# Fade *argin

1 !p ' 9&0 mile minimum antenna /ei%/t o+ 45 +t&

5&5 !p ' 5&7 mile minimum antenna /ei%/t o+ 36 +t&

11 !p ' 4&0 mile minimum antenna /ei%/t o+

31 +t& 24 !p ' 2&0 mile minimum antenna /ei%/t

o+ 26 +t& 54 !p ' 0&4 mile minimum antenna

/ei%/t o+ 14 +t&




,oncl%sions

•

d%cation is Best *eans to ,onfidence– Relia&ility is only as good as t#e system design

• Use t#e Tools

– ,om"are different vendor;s #ardware– Review s"ecifications and claims

• Radio A""lications Are )ot Diffic%lt

– Planing and eval%ation are &est keys to s%ccess

SECTION 4 - RF System Design.ppt

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Transcript of SECTION 4 - RF System Design.ppt