A Brief Introduction for Designing a Patch Antenna Using CST
1. Accessing CST MWS
a. From start menu select Programs > CST STUDIO SUITE 2006 > CST
DESIGN ENVION!ENT
". T#e ma$n %$n&o% s#o%n $n F$g. ' %$ll "e o(ene&
c. From t#e ma$n %$n&o% cl$c) on *CST !$cro%a+e Stu&$o, $con t#en cl$c)
O-
F$g. ' CST ma$n %$n&o%
&. . ne% (o(/u( %$n&o% calle& *Create a Ne% (ro0ect, %$ll a((ear1 2rom t#$s
%$n&o% t#at s#o%n $n F$g. 2 3ou can select t#e t3(e o2 (ro0ect 3ou are
%or)$ng on1 $.e. .ntenna 4on (lanar su"strate5 $n case o2 &es$gn$ng a
Click Here
then click OK
m$crostr$( (atc# antenna or .ntenna $n 2ree s(ace $n case o2 &es$gn$ng a
&$(ole or a mono(ole.
Note: the purpose from selecting the project type is to adjust the boundary
condition automatically, if you dont like this you can select None and
you can adjust the boundary conditions later.
F$g. 2 Create ne% (ro0ect %$n&o%
e. .2ter cl$c) on O- t#e ma$n la3out %$n&o% %$ll a((ear as s#o%n $n F$g. 6.
No% %e nee& to g$+e a name to t#e (ro0ect an& sa+e $t.
2. From !a$n !enu select > F$le > Sa+e as1 no% 3ou s#oul& %r$te t#e name o2
3our (ro0ect $n t#e s(ec$2$e& area e.g. *ectangular Patc#, as s#o%n $n F$g. 7
F$g. 6 !a$n 8a3out %$n&o%
F$g. 7 Sa+$ng t#e %or)$ng (ro0ect
Write the
project
name here
2. Rectangular patch antenna design
Step 1 specifying the project units
From ma$n menu select > Sol+e > Un$ts1 t#en 2rom t#e un$ts %$n&o% select
t#e &$mens$ons to "e $n mm1 Fre9uenc3 $n G:; an& t$me to "e $n ns as s#o%n $n
F$g.<.
F$g. < !a$n un$ts &e2$n$t$on
Step 2 Assigning the Background aterial
From ma$n menu select > Sol+e > =ac)groun& !ater$al1 No% a ne%
%$n&o% calle& *=ac)groun& (ro(ert$es, %$ll (o( u(. C#oose !ater$al t3(e to "e
normal an& )ee( all ot#er (arameters as t#e &e2aults as s#o%n $n F$g. 6
F$g. 6 =ac)groun& mater$al &e2$n$t$on
Step ! Antenna su"strate definition
From ma$n menu select > O"0ects > =as$c S#a(es > =r$c)1 T#en &ou"le
cl$c) on t#e %or)$ng area an& &rag t#e mouse an& &ou"le cl$c) aga$n to en& t#e
&ra%$ng mo&e. No% a ne% %$n&o% calle& *=r$c), %$ll a((ear1 2rom t#$s %$n&o%
t#at s#o%n $n F$g.> 3ou can a&0ust t#e re9u$re& &$mens$ons o2 t#e su"strate1 $ts
name an& $ts mater$al.
In t#$s (ro0ect %e nee& to a&0ust t#e su"strate &$mens$ons to "e '00?'00
mm
2
"3 c#ang$ng Xmin to "e /<0 an& Xmax to "e <0 an& min to "e /<0 an& max
to "e <0. .n& $n t#$s e@am(le %e %$ll c#oose t#e t#$c)ness o2 t#e su"strate to "e
'.<>< mm1 so c#ange !min to "e /'.<>< an& !max to "e 0.
For t#e su"strate mater$al %e nee& to c#ange $t to T <AA0 4B
r
C2.25 to &o t#at
cl$c) on t#e mater$al select "o@ an& c#oose *8oa& 2rom mater$al l$"rar3, t#en
select t#e mater$al state& "e2ore as s#o%n $n F$g.A
F$g. > Su"strate &e2$n$t$on
F$g. A C#ang$ng t#e !ater$al o2 t#e su"strate to T <AA0
Click here
to assign
the
substrate
material
Click here
to change
the
dimension
s
Step # Antenna ground definition
For t#e antenna groun& 3ou nee& to create anot#er "r$c) *same as state&
"e2ore, %$t# a +er3 t#$n t#$c)ness 4I c#oose $t to "e 0.' mm5 as s#o%n $n F$g.D an&
c#ange $ts mater$al to "e co((er
F$g. D .&&$ng t#e groun& (lane o2 t#e antenna
Step $ %ra&ing the radiating patch
To &ra% a rectangular (atc# create anot#er "r$c) %$t# t#e 2ollo%$ng
(arameters Xmin C 4/7D.7E251 Xmax C 47D.7E25 an& min C 4/7'.6E251 max C
47'.6E25. .n& !min C 01 !max C 0.' an& ass$gn $ts mater$al to "e co((er as s#o%n
$n F$g.'0.
Step ' %ra&ing inset feed slot
Create a "r$c) %$t# t#e 2ollo%$ng (arameters Xmin C 4/7'.6E251 Xmax C 4/
7'.6E2 F'7.<5 an& min C /6.<1 max C 6.<. .n& !min C 01 !max C 0.' an& ass$gn
$ts mater$al to "e co((er as s#o%n $n F$g.''.
F$g. '0 Dra%$ng t#e ra&$ator (atc#
F$g.'' Dra%$ng t#e $nset 2ee& slot
Step ( Cutting the inset feed slot fro the patch
a. From t#e le2t (ane cl$c) on *Coponent1) to s#o% all t#e com(onents o2 3our
(ro0ects
". Cl$c) on (atc# to select $t
c. Cl$c) on *=oolean su"tract 4/5, $con 2rom t#e tool"ar1 see F$g.'2
&. No%1 cl$c) on slot an& (ress enter )e31 see F$g. '6
e. Gou s#oul& no% see somet#$ng loo)s l$)e F$g.'7
F$g. '2 Cutt$ng t#e $nset 2ee& slot 2rom t#e (atc# 4a1"1c5
Boolean
subtract
icon
Select
Patch
F$g. '6 Cutt$ng t#e $nset 2ee& slot 2rom t#e (atc# 4&5
F$g. '7 Cutt$ng t#e $nset 2ee& slot 2rom t#e (atc# 4e5
Select
slot
Step * %ra&ing the $+ oh feed line
Create a "r$c) %$t# t#e 2ollo%$ng (arameters Xmin C 4/7.A<E251 Xmax C
47.A<E25 an& min C /<01 max C 0. .n& !min C 01 !max C 0.' an& ass$gn $ts
mater$al to "e co((er as s#o%n $n F$g.'<.
F$g.'< Dra%$ng t#e <0 o#m 2ee& l$ne
Step , Merging the feed line &ith the patch
a. From t#e le2t (ane un&er "omponent # su"/menu cl$c) on $eedline t#en #ol&
t#e ctrl )e3 $n t#e )e3"oar& an& cl$c) on %atch to select "ot# o2 t#em
". From t#e tool"ar cl$c) on *=oolean a&& 4F5,1 see F$g.'6
c. No% t#e3 are merge& toget#er an& "ecome one com(onent as s#o%n $n F$g.'>
F$g.'6 !erg$ng t#e 2ee& l$ne %$t# t#e (atc#
Boolean
Add icon
Select
feedline
and Patch
F$g.'> T#e 2ee& l$ne an& t#e (atc# a2ter merg$ng
Step 1+ %efining the &a-e port for the antenna
a. From ma$n menu select > Sol+e > %a+egu$&e (orts or "3 cl$c) on %a+egu$&e
(orts $con $n t#e tool"ar
". From t#e &a'eguide (ort %$n&o% select Normal to "e
c. Select 2ree $n t#e (os$t$on "o@ an& enter t#e 2ollo%$ng &$mens$ons 2or t#e %a+e
(ort H Xmin C /201 Xmax C 20 an& !min C /'.<><1 !max C '0
&. C#ec) *2ree normal (os$t$on, $n (os$t$on "o@ an& c#ange pos to be ()* as
s#o%n $n F$g.'A
e. .2ter 3ou cl$c) o) 3ou s#oul& see (ort ' &e2$ne& as s#o%n $n F$g.'D
F$g.'A De2$n$t$on o2 t#e %a+e (ort
F$g.'D De2$n$t$on o2 t#e %a+e (ort
Select Y
Select
ree
Check free
normal
position
Step 11 %efining the siulation fre.uency range
a. From ma$n menu select > Sol+e > Fre9uenc3 or "3 cl$c) on 2re9uenc3 range
$con $n t#e tool"ar
". Enter t#e 2re9uenc3 range o2 3our s$mulat$on as $min C'1 $maxC< t#en cl$c) o)
F$g.20 De2$n$t$on s$mulat$on 2re9uenc3 range
Step 12 Adding radiation pattern and surface current to your siulation results
a. From ma$n menu select > Sol+e > F$el& !on$tors or "3 cl$c) on 2$el& mon$tors
$con $n t#e tool"ar
". From !on$tor %$n&o% select $arfield+,"- 2or (lott$ng t#e ra&$at$on (attern an&
t3(e t#e mon$tor$ng 2re9uenc3 4$n t#$s e@am(le $t $s 2.7 G:;5 t#en cl$c) a((l3
as s#o%n $n F$g.2'
c. To (lot t#e sur2ace current &$str$"ut$on select .(field+-urface current an& t3(e
t#e mon$tor$ng 2re9uenc3 t#en cl$c) a((l3
F$g.2' .&&$ng ra&$at$on (attern4s5 an& sur2ace current to t#e s$mulat$on results
!onitoring
fre"uenc#
ield
monitor
icon
Step 1! Running the siulation
a. From ma$n menu select > Sol+e > Trans$ent sol+er or "3 cl$c) on Trans$ent
sol+er $con $n t#e tool"ar
". Form trans$ent sol+er %$n&o% 3ou can a&0ust t#e sol+er accurac3 *t#e error
marg$n, $n t#$s e@am(le I c#oose $t to "e /60 &= t#en cl$c) start as s#o%n $n
F$g.22
F$g.22 unn$ng t#e trans$ent sol+er
Notes:
#. /ncreasing the accuracy resulting in slo&er simulation
0. 1here are more sol'ers in "-1 package like fre2uency domain sol'er and eigen
mode sol'er but in this example &e choose only the transient sol'er to be
presented
$ransient
sol%er
icon
Step 1# %isplaying the siulation results
a. To s#o% t#e S/ (arameter cur+es 4$.e. l$near1 &=1 (#ase1 sm$t# c#art1I.. 5 go to t#e
le2t (ane t#en cl$c) on #3 ,esults t#en select t#e cur+e 3ou %ant to &$s(la3 as
s#o%n $n F$g.26
". To s#o% t#e current &$str$"ut$on (lots go to t#e le2t (ane t#en cl$c) on 03+43
,esults t#en select Sur2ace current > #/2$el&s as s#o%n $n F$g.27
c. To s#o% t#e ra&$at$on (attern4s5 (lots go to t#e le2t (ane t#en cl$c) on 03+43
,esults t#en select Far2$el&s > 2ar2$el& 42C2.75 as s#o%n $n F$g.2<
F$g.26 D$s(la3$ng S/(arameter cur+es
&ispla#
S
''
in dB
F$g.26 D$s(la3$ng current &$str$"ut$on (lots
&ispla#
the
current
distributi
on
F$g.27 D$s(la3$ng ra&$at$on (atterns (lots
&ispla#
the
radiation
pattern(s)
Step 1$ %isplaying the post processing results
a. To s#o% some (ost (rocesse& results 4$.e. VSJ1 K/(arameters1 grou( &ela31
II.5 go to t#e ma$n menu > Tem(late "ase& (ost(rocess$ng as s#o%n $n F$g.2<
". From Tem(late "ase& (ost(rocess$ng %$n&o% select t#e gra(# 3ou %ant to &$s(la3
4$n t#$s e@am(le I ($c) VSJ5 t#en cl$c) E+aluate as s#o%n $n F$g.26
c. No%1 go to t#e le2t (ane t#en select 'D esults > Ta"les > ' D results > VSJ to
s#o% t#e (lot as s#o%n $n F$g. 2>
F$g.2< D$s(la3$ng t#e (ost (rocess$ng results 4a5
F$g.26 D$s(la3$ng t#e (ost (rocess$ng results 4"5
F$g.2> D$s(la3$ng t#e (ost (rocess$ng results 4c5
References:
For &eta$ls o2 CST &ocumentat$on 3ou ma3 seeH
http://www.cst.com/Content/Products/MWS/Overview.aspx
