In
he i s case, one inpu o he analyse is used o p ocess he
il e ou pu node and he o he cons i u es he addi ional obse a-
ion poin . Ob iously, his poin has o be judiciously chosen o be
able o ob ain an inc ease in aul co e age.
So,
he wo analyse
inpu s a e connec ed o (i) he ou pu node o he d e and (ii) he
ou pu node o he op-amp di e en ial s age
as
shown in Fig.
2.
The
HSPICE
aul simula ions show ha in his si ua ion, only
one aul is no de ec ed. The co esponding aul co e age is
equal o:
FC,,
(V,,, and
V&)
=
97.9%.
1
Salien
-key
il e
I
“0”
TC
A5
Fig.
3 Mixed
ol uge/cu en
es ing
In
he second case, one inpu o he analyse is used o p ocess
he il e ou pu and he o he o obse e he supply cu en . Since
he analyse is designed o ol age in eg a ion, an addi ional sub-
ci cui is equi ed o p o ide a ol age
V,,,
which is an image o
he supply cu en I, o he CUT. The wo analyse inpu s a e
hen connec ed o (i) he ou pu node
V,,,
o he il e and (ii) he
ou pu node
V,,
o he
I-V
con e e . as illus a ed in Fig.
3.
The
I-V
con e e we use is based on wo k ela ed in [7] o he a ea o
cu en senso de elopmen . Faul simula ion esul s show ha
his s uc u e allows
us
o de ec
47
o he 48 aul s o he il e .
The esul ing aul co e age is equal o:
FC,,
(E,,
and I,>
=
So
in bo h cases, we can obse e a signi ican inc ease in he
aul co e age achie ed when compa ed o
a
classical ime-domain
analysis: om
85.4%
up o 97.9%. This imp o emen in ci cui
es abili y is achie ed while main aining a easonable a ea o e -
head since a single opamp is equi ed o build he analogue signa-
u e. Fu he mo e, i has o be emphasised ha usually, when
using signa u e analysis echniques, he p oblem is o minimise he
numbe o e o masking phenomena in o de o ob ain
a
aul
co e age as close as possible o he aul co e age achie ed by an
ex e nal es . Wi h he mul iple-inpu analogue analyse , no only
can we pa ially o e come aliasing p oblems by in oducing edun-
dancy, bu also we gain an imp o emen in aul co e age. This
solu ion consequen ly goes beyond he classical objec i es o sig-
na u e analysis echniques.
97.9%.
Conclusion: Based on he use o he in eg a ion unc ion as an
analogue compac ion echnique, we ha e p oposed
a
sys em o
de i ing a signa u e o analogue ci cui s.
A
signa u e analyse can
he e o e be de ined and easily implemen ed using an on-chip op-
amp-based in eg a o . This pe mi s us o eplace he ha d- o-man-
age ex e nal moni o ing o a con inuous ime- a ying esponse by
a
simple single-sho analogue measu emen . Fu he mo e, he abil-
i y
o
ou mul iple-inpu analyse o concu en ly moni o di e -
en in e nal es poin s allows us o pa ly o e come he aliasing
p oblem and o imp o e ci cui es abili y. I is shown ha by
using mul iple-node ol age es ing, we can d as ically inc ease he
aul co e age achie ed o a Sallen-key il e .
Also,
i is shown
ha ou sys em allows he implemen a ion o concu en con ol
o bo h ol age and cu en le els, hus allowing
us
o ully p o i
om he complemen a i y be ween ol age and I,, es echniques.
0
IEE
1996
4
Oc obe
I996
Elec onics Le e s Online No: 19961511
M. Reno ell,
F.
Azals and Y. Be and (Labo a oi e d’ln o ma ique,
Robo ique e Mic oClec onique
de
Mon pellie (LIRMM), UMR
55506,
Uni e si C de Mon pellie
IUCNRS,
161,
Rue
Ada,
34392
Mon pellie
Cedex
5,
F ance)
Re e ences
ABRAMOVICI,
M.,
BRAUER, M.A.,
and
FRIEDMAN,
A.D.:
‘Digi al sys ems
es ing and es able designs’ (Compu e Science P ess, New Yo k,
1995)
RAJSKI,
J.,
and
TYSZER,
J.: ‘The analysis o digi al in eg a o s o es
esponse compac ion’,
IEEE
T ans. Ci cui s Sys .
11,
1992, pp.
OHLETZ,
M.J.:
‘Hyb id buil -in sel - es (HBIST) o mixed analogue/
digi al in eg a ed ci cui s’. P oc. Eu opean Tes Con ., 1991, pp.
307-3 16
NAGI,
N.,
CHATTERJEE,
A.,
and
ABRAHAM,
J.A.:
‘A
signa u e analyze
o analog and mixed-signal ci cui s’. P oc. In . Con . Co npu .-
Aided-Des., 1994,
pp.
286287
BELL,
I.M.,
CAMPLIN,
D.A.,
TAYLOR,
G.E.,
and
BANNISTER,
B.R.:
‘Supply
cu en es ing o mixed analogue and digi al ICs’, Elec on. Le .,
1991, 27, (17). pp. 1581-1583
MACHADO
DA
SILVA,
J.,
MATOS,
JS.,
BELL,
I.M.,
and
TAYLOR,
G.E.:
‘C oss co ela ion be ween
I,,
and
V,,,
signals o es ing analog
ci cui s’, Elec on. Le ., 1995, 31, (19), pp. 1617-1618
ROCA,
M.,
and
RUBIO,
A.:
‘Sel es ing CMOS ope a ional ampli ie ’,
Elec on. Le ., 1992,
28,
(5),
pp. 1452-1454
293-301
Pe u ba ion
o
he Sie pinski an enna o
alloca e ope a ing bands
C.
Puen e,
J.
Romeu, R. Ba olemi:
and
R.
Pous
Indexing e ms: An ennas, F ac als, An enna a ays
A
scheme o modi ying he spacing be ween he bands
o
he
Sie pinslu an enna
is
in oduced. Expe imen al esul s o wo
no el designs o ac al an ennas sugges ha he ac al s uc u e
can be pe u bed o enable he log-pe iod o be changed while s iU
main aining he mul iband beha iou o he an enna.
In oduc ion: The applica ion
o
ac al s uc u es o he design
o
an ennas has been ecen ly desc ibed [l
-
31.
In he Sie pinski
an enna, p esen ed in
[2,
41,
bo h he inpu and he adia ion pa -
e ns ha e a log-pe iodic beha iou . The log-pe iod
(6)
had a ac-
o o
2
(6
=
2),
he same scale ac o ha cha ac e ised he
geome ical sel -simila i y p ope ies o he ac al objec . He e, we
desc ibe some expe imen al esul s on wo no el s uc u es based
on he Sie pinski gaske , which p esen di e en log-pe iods
(6
=
1.66 and
6
=
1.5). The esul s sugges a me hod o pe u bing he
Sie pinski s uc u e in such a way as o con ol he posi ion o
mul iple bands whe e necessa y.
P3/
5SPK
P2
/3SPK
a
b
Fig.
1
Two
no el designs and o iginal Sie pinski an enna
a
P3I5SPK an enna
b P213SPK an enna
c
O iginal Sie pinski an enna
Design: The beha iou o he Sie pinski an enna has been
explained h ough he exis ence
o
a
cu en densi y ac i e egion
2186
ELECTRONICS LETTERS
21s
No embe
1996
Vol.
32
No.
24
o e a ac al su ace
[4].
Such an ac i e egion sel -scales a each
wa eleng h in an analogous way, which has been p e iously
desc ibed o he log-pe iodic dipole a ay and o he spi al
an enna
[5].
Tha is, a sho wa eleng hs, he cu en ends o
concen a e owa ds he eeding poin in a egion whe e a small
copy o he o e all shape o he an enna is loca ed. This egion o
he an enna has he mos signi ican con ibu ion o adia ion and
he es o he an enna ou side i becomes e ec i ely disconnec ed.
This Le e aims o show how, by pe u bing he cha ac e is ic
scale ac o o he ac al shape, he adia ing bands can be
shi ed.
The wo no el designs a e plo ed in Fig.
1
oge he wi h he
o iginal Sie pinski an enna
[2].
Bo h ha e he o e all o m epli-
ca ed a i e di e en scales a he base o he an enna, he smalle
copy being a single iangle. The an ennas a e designed by means
o an i e a i e algo i hm ha basically consis s in sub ac ing a
scaled iangle om he o iginal iangula o m [6]. A each i e a-
ion, a educ ion ac o o 315 is ound on he lowe iangula
clus e o he i s an enna (he ea e P315SPK) and
a
educ ion
ac o o 213 is ound on he second one (he ea e P213SPK). We
no e ha he wo uppe iangula clus e s ha emain a e each
sub ac ion a e no p opo ional copies o he o e all shape bu
a e a he dis o ed.
An
a ine ans o ma ion a he han a simi-
la i y ans o ma ion should be applied o go om he o e all
s uc u e o hese skewed gaske s, and hence he o m is said o be
sel -a ine
[6]
ins ead o sel -simila . Ne e heless,
a
simila i y ela-
ion holds o he lowe clus e whe e he ac i e egion is expec ed
o be concen a ed, and hence a sel -simila elec omagne ic
beha iou can be expec ed o bo h s uc u es.
P315SPK
"6
LJ"6-l
-
0.45
161 3.51
2.76 1.71
4.54 1.65
7.52 1.66
300
4
-
200
0
2
100
0
P2/3SPK Sie pinski
"6
"6/"6-l
"6
L/ -l
0.44 ~ 0.46
1.54 3.46 1.75 3.77
2.43 1.57 3.51 2.00
3.69 1.51 7.01 2.00
5.43 1.47 13.89 1.98
-
200
100
-0
--200
N
m
,.-IO0
200,
, , ,
, ,
, , ,
,
,
,
,
100
-0
--200
N
m
,.-IO0
2
L
6
8
10
12
,
GHz
Fig.
2
Inpu e ec ion coe icien ela i e o
1500
( zn'50"),
inpu esis -
ance
and
eac ance
o
h ee an ennas
P315SPK
P213SPK
. . . . .
. . . .
. .
Sie pinski
~-~~
Expe imen al esul s:
The an ennas we e p in ed o e
a
Cuclad
250
dielec ic subs a e
(E,
=
2.5
and h
=
1.58Smm)
using s anda d
p in ed ci cui echniques, and moun ed on a monopole con igu a-
ion o e
a
80
x
80cm squa e conduc o g ound plane. The an en-
nas' inpu e lec ion coe icien ela i e o
50Q
we e measu ed
om 200MHz o 12GHz using an HP8510B. Such coe icien s
we e eno malised wi h espec o
1500
which is he impedance
ha be e i s he an enna inpu impedance a each band (an i-
esonan equencies). Such e lec ion coe icien s
nlson)
oge he
wi h he eal and imagina y pa s o he inpu impedance
(ZJ
a e
plo ed in Fig.
2;
he co esponding pa ame e s o he p e iously
epo ed Sie pinski an enna
[4]
a e shown o compa ison as well.
To
show he log-pe iodic beha iou
o
he h ee an ennas, he es-
onan equencies oge he wi h he spacing ac o among hem
a e lis ed in Table 1. The da a display an almos log-pe iodic dis-
ibu ion o he uppe bands wi h log-pe iods
6
=
1.66 (513) o he
P3/5SPK an enna and
6
=
1.5 (3/2) o he P2/3SPK an enna,
which a e he scale ac o s ha cha ac e ise hei ac al body. The
lowe bands a e shi ed owa ds he o igin due o he unca ion
e ec and a e close o ha o a bow- ie an enna as desc ibed in
The pa e ns o he wo no el designs we e measu ed in an ane-
choic chambe a he cen e o he ou uppe bands (Figs. 3 and 4).
[41.
15
30
0
180
06
60
6
D
90
90
90
90
21
30
240
270
3w
I20
90
KO
1
30
KO
-6
0
18
0
90-90
30
210
300
120
90
60
1
30
0
30
0
0
180
(3
-6
E:
90
90-90
90
21
d
240
270
300
8
=
q=O"
(p=QO"
e=w
m
Fig.
3 Main cu s
(cp
=
Oo,
cp
=
904
8
=
909
o adia ion pa e ns
o
P3/5SPK an enna
P2l3
SPK
0
0
120
90
60
30
0
8
60
60
6
90
90
90
30
120
60
8
30
30
1
30
8
-6
60
6
0
0
180
p
90
90.90
90
21
30
77"
_.
120
60
240
270
300
(p'0"
(p=90" 0=90"
ma
Fig.
4
Main
cu s
(cp
=
O",
@
=
90°,
8
=
909
o
adia ion pa e ns o
P2/3SPK an enna
ELECTRONICS LETTERS 21s No embe
1996
Vol.
32
No.
24
2187
Conclusions:
Two no el designs o ac al mul iband an ennas
ha e been in oduced. The an ennas we e designed by pe u bing
he shape o he Sie pinski an enna. The spacing be ween bands is
again ela ed o he cha ac e is ic scale ac o
o
he ac al s uc-
u e, which sugges s a p ocedu e o uning he an enna o a
equi ed se o bands. The mul iband beha iou is consis en bo h
om he inpu impedance and adia ion pa e n poin s o iew.
Acknowledgmen s:
The au ho s would like o hank P.Mayes om
he Uni e si y o Illinois o encou aging his wo k. They also
hank A.Hijazo and M.Na a o €o con ibu ions on he an enna
design and measu emen s. This wo k has been mancially sup-
po ed by he ‘Spanish Commission o Science and Technology’
unde g an TIC-96-0724-‘206-04,
0
IEE
1996
Elec onics Le e s Online
No:
19961476
C. Puen e,
J.
Romeu, R. Ba olem and R. Pous (D3-Elec omagne ics
and Pho onics Enginee ing G oup, Signal Theo y and Communica ions
Depa men , Uni e si a Pol dcnica de Ca alunya, G an Capi d
s/n,
MddulD3, 08034 Ba celona, Spain)
7 Oc obe 1996
Re e ences
1
PUENTE,
c.,
and
POUS,
R.:
‘F ac al design
o
mul iband and low side-
lobe a ays’, IEEE T ans. An ennas P opag., 1996,
44,
(5),
pp.
730-
739
2
PUENTE,
c.,
ROMEU,
J.,
POUS,
R,
GARCIA,
x,
and
BEN~TEZ,
F.:
‘F ac al
mul iband an enna based on he Sie pinslci gaske ’, Elec on. Le .,
1996,
32,
(l), pp. 1-2
3
COHEN,
N.,
and
HOHLFELD,
R.G.:
‘F ac al loops and he small loop
app oxima ion’, Commun. Qua e ly, 1996, pp.
77-8
1
4
PUENTE,
c.,
ROMEU,
J.,
POUS,
R.,
and
CARDAMA, A.:
‘On he
beha iou o he Sie pinski mul iband ac al an enna’, IEEE
T ans. An ennas P opag., 1996, (Submi ed)
5
RUMSEY,
V.H.:
‘F equency independen an ennas’ (Academic P ess,
New Yo k, 1966)
6
PEITGEN,
H.o., JURGENS,
H.,
and
SAUPE,
D.: ‘Chaos and ac als, new
on ie s o science’ (Sp inge -Ve lag, New Yo k, 1992)
40Gbi /s
OTDM
soli on ansmission o e
ansoceanic dis ances
G.
Aubin,
T.
Mon alan , J. Moulu,
F.
Pi io,
J.-B.
Thomine and
F.
De aux
Indexing e ms: Soli on ansmission, Time di ision mul iglexing
40GbiVs soli on ansmission is achie ed in a eci cula ing
loop
o e 100001m, o he i s ime o he au ho s’ knowledge, wi h a
single ca ie wa eleng h. P opaga ion has been es ed wi h and
wi hou pola isa ion mul iplexing hanks o low pola isa ion
dependency elec oabso p ion modula o s o in-line con ol and
o he
ime
demul iplexing ecei e .
In oduc ion:
Soli on ansmission is an a ac i e candida e on
which o base op ical ansoceanic sys ems al hough i equi es in-
line passi e o ac i e con ol o achie e high capaci y o e long
dis ances [2]. Thanks o i s nonlinea cha ac e is ic, i allows noise
ejec ion ou o he signal bandwid h. In pa icula , op ical egen-
e a ion can be achie ed by inco po a ing equency il e ing and
in-line synch onous in ensi y modula ion. This echnique limi s he
inc ease in ampli ude noise and iming ji e , allows ansmission
o e unlimi ed dis ance [2] and
a
la ge epea e span
[3].
I was
shown o be possible by he simula ion esul s in
[4]
and i is dem-
ons a ed he e expe imen ally o he i s ime o ou knowledge
ha 40Gbi is ansoceanic ansmission can be ache ed on a sin-
gle ca ie wa eleng h when he longes haul epo ed wi h pe i-
odic dispe sion compensa ion is
500Okm
[5].
This me hod does no p eclude he use o WDM ansmission,
as i has been demons a ed wi h a bina y e o a e (BER) o
<
1@* a l0000km [6] and could be compe i i e wi h he sliding
echnique [7].
2188
ELECTRON1
Expe imen :
The se up includes a 180km long eci cula ing loop
ope a ing as in ou p e iously published expe imen s
[3,
41 and is
shown in Fig. 1.
T ansmission has been es ed wi h wo di e en 40Gbi ls pulses
ansmi e s. Adjacen pulse pola isa ion
is
o hogonal in one and
pa allel in he o he .
pa e n
20GHz
aene a o
UU
.
I”
op ical clack
ecei e eco e y
ib e
EDFA
ib e
-
4
imes
Fig.
1
Expe imen al se up
The i s ansmi e gene a es 2OGbi /s 27-1 pseudo andom
pa e n pulses om a 1.5572~ DFB lase and h ough wo
InGaAsP-InGaAsP mul iquan um well (MQW) elec oabso p ion
idge modula o s and an ampli ie in eg a ed on he same chip
using a common ac i e laye
[XI.
The sho pa e n leng h is lim-
i ed by he elec onic d i e made in ou labo a o y.
A
second
s age eshapes hese pulses using a Mach-Zehnde li hium nioba e
op ical in ensi y modula o d i en a 2OGHz. Op ical ime mul i-
plexing is ealised a e spli ing a 20Gbi /s s eam. The pulse ain
is in e lea ed wi h i sel a e an adequa e delay ob ained using
p ecise ib e leng h. A pola isa ion combine p o ides o hogonal
s a es be ween consecu i e pulses wi h an ex inc ion a io
>
han
25dB.The ou pu a e age pulsewid h measu emen gi es 17ps wi h
a s eak came a.
The second 1.5572~ sou ce uses he same 20GbiUs modula-
ion bu 20GHz pulses come by a mode-locked ib e ing lase
ins ead o an elec oabso p ion modula o (EAM) and a DFB
lase . An iden ical passi e echnique achie es
2040
Gbi is op ical
mul iplexing o p o ide 27-1 pseudo andom pa e n. Howe e ,
ela i e pola isa ion s a es a e managed he e in each b anch o a
con en ional couple in o de o op imise he ou pu alignmen
h ough he main axis
o
a pola ise ha main ains he same pa -
allel pola isa ion o e e y launched pulses. The 7ps a e age
pulsewid h is sho e han he p e ious one and be e ex inc ion
allows us o ansmi hem wi hou any esidual in e e ence bea -
ing.
The p opaga ion pa h con ains a modula ion con ol sec ion
ollowed
by
ou
45km
long ib e spans.
Loss
compensa ion is
ealised by 980nm pumped ampli ying and il e ing by an in e e -
en ial de ice
in
each sec ion. The
loop
expe imen needs ano he
ampli ie o balance swi ch and couple a enua ion and o each
sui able powe s. The a e age ib e inpu powe measu ed h ough
99:l couple s placed jus in on
o
he 12.5dB loss ib e spools
is
hen -5dBm. The combina ion o in-line op ical bandpass d e s
leads o a 0.77nm
FWHM
Gaussian shaped il e ing pe 180km.
A sho piece o 17psld km s ep-index ib e has been spliced o
dispe sion-shi ed ib es (DSF) in o de o se he ch oma ic dis-
pe sion a 0.2ps/nm/km in each ampli ying span. The esynch o-
nising sec ion comp ises a
hgh
bandwid h op ical ecei e o
eco e he 40GHz clock s aigh om 40Gbi is pulses and an
EAM
[9]
d i en by esul ing 40GHz, 20dBm sinusoid o eshape
in-line pulses wi h a o al pola isa ion dependency loss (PDL) o
<
1 dB.
S aigh 40 o lOGbi is demul iplexing is ealised wi h ano he
MQW
EAM [9] d i en sinusoidally a l0GHz wi h c ea ed sub-
ha monics coming om a second 40GHz clock eco e y de ice.
The BER is measu ed a e his op ical ime demul iplexing by
using a 10Gbi is comme cial BER coun e igge ed wi h a
delayed ga e co espondmg o he p opaga ion dis ance. A he
‘CS LETTERS
21s
No embe
7996
Vol.
32
No.
24