Dual-Band VHF/UHF Monopole with

Double Loop Antenna for Nanosatellites

SpaceConcordia,ConcordiaUniversity,

Montreal,QC,Canadah"p://www.spaceconcordia.ca

ZouhairBriqech,KentonNeustaeter,MariyaKrasteva,EmmanuelPapanagiotou,JanClarenceDee,andAbdelrazikSebak

1CSCA 2016 Toronto, ON, Canada February 2-3, 2016

Outlines

! Aleksandr’sAntennas! Communica3onSystemDiagram

! Dual-BandVHF/UHFMonopoleAntenna

! Dual-Band VHF/UHF Monopole withDoubleLoopAntenna

! ParametricalStudies

! Radia3onPaGerns! RealizedGainComparison

! Prototypesandpreliminaryresult

! Summary

2

Version1.0Dual-BandVHF/UHFMonopoleAntenna

Aleksandr’s Antennas

Version2.0Dual-BandVHF/UHFMonopolewith

DoubleLoopAntenna

3

Helium100Transceiver

CentralProcessor

Rx

Tx

Diplexer438MHz146MHz Deployable

MonopoleAntenna

VHF/UHVAntenna

[*]T.F.C.Leao,,V.M.Chopin,Ch.W.Trueman,andS.Gleason."DesignandImplementaXonofaDiplexerandaDual-BandVHF/UHFAntennaforNanosatellites."AntennasandWirelessPropagaXonLe\ers,IEEE12,pp.1098-1101,2013

[*]

Communication System

4

Frequency (MHz)100 200 300 400 500

S 11

(dB)

-30

-25

-20

-15

-10

-5

0

5

L = 450 mmL = 500 mmL = 550 mmL= 600 mmL = 650 mmL = 700 mm

600 mm

550 mm 450 mm

438MHz 146MHz

L

The current density magnitude on theantenna element at 146MHz is a λ/4standingwave,andat438MHzisa3λ/4standingwave.

Dual-Band VHF/UHF Monopole Antenna

5

Zin

La

rb

rc

gb

gc

Lc

Lc

kc

kb

vb

vc

Isolators

438MHz 146MHz

Calculation Software Tool: Computer System Technology Microwave Studio (CST MWS) based on finite integration technique (FIT) in time domain

Dual-Band VHF/UHF Monopole with Double Loop Antenna

6

La

Frequency (MHz)

100 200 300 400 500

S 11

(dB)

-60

-50

-40

-30

-20

-10

0

La = 510 mmLa = 528 mmLa = 546 mmLa = 564 mmLa = 582 mmLa = 600 mm

Increasing the La leads to decreasing the main center frequency of the VHF and UHF band.

Parametrical studies

7

0

+

-

Zb

265 mm

Frequency (MHz)

100 200 300 400 500

S 11

(dB)

-40

-30

-20

-10

0

Zb = -20.75 mmZb = -8.75 mmZb= 15.25 mmZb = 27.25 mmZb = 39.25 mm

UHF - band

VHF - band

Changing Zb “the large loop position” has an effect on the antenna matching bandwidth at VHF band, while it has no varying impact on UHF band.

Parametrical studies (cont.)

8

Lb

Frequency (MHz)

100 200 300 400 500

S 11

(dB)

-60

-50

-40

-30

-20

-10

0

Lb = 393 mmLb = 409 mmLb = 434 mmLb = 467 mmLb = 505 mmLb = 547 mm

Changing Lb “the length of large loop” has an effect on the antenna matching bandwidth at both VHF band and UHF band.

Parametrical studies (cont.)

9

0

+

Zc

104 mm

Frequency (MHz)100 200 300 400 500

S 11

(dB)

-60

-50

-40

-30

-20

-10

0

Zc = 125 mmZc = 100 mmZc = 75 mmZc = 50 mmZc = 25 mmZc = 0 mm

UHF - band

Changing Zc “the small loop position” has an effect on the antenna matching bandwidth at UHF band, while it has very small impact on VHF band.

Parametrical studies (cont.)

10

Lc

Frequency (MHz)

100 200 300 400 500

S 11

(dB)

-60

-50

-40

-30

-20

-10

0

Lc = 149 mmLc = 164 mmLc = 181 mmLc = 201 mmLc = 223 mmLc = 251 mm

UHF - bandVHF - band

Changing Lc “the length of the small loop” has an effect on the antenna matching bandwidth at UHF band, while it has no varying impact on VHF band.

Parametrical studies (cont.)

11

150 Mhz 0

30

60

90

120

150180

210

240

270

300

330

-25 -20 -15 -10 -5 0-25

-20

-15

-10

-5

0

-25-20-15-10-50-25

-20

-15

-10

-5

0

E-PlaneH-PlaneHPBWE = 80.3

o

143 Mhz 0

30

60

90

120

150180

210

240

270

300

330

-25 -20 -15 -10 -5 0-25

-20

-15

-10

-5

0

-25-20-15-10-50-25

-20

-15

-10

-5

0

E-PlaneH-PlaneHPBWE = 81.2

o

146 Mhz 0

30

60

90

120

150180

210

240

270

300

330

-25 -20 -15 -10 -5 0-25

-20

-15

-10

-5

0

-25-20-15-10-50-25

-20

-15

-10

-5

0

E-PlaneH-PlaneHPBWE = 80.8

o

Radiation Patterns at VHF Band

3D Radiation Pattern at 146 MHz 12

442 Mhz 0

30

60

90

120

150180

210

240

270

300

330

-25 -20 -15 -10 -5 0-25

-20

-15

-10

-5

0

-25-20-15-10-50-25

-20

-15

-10

-5

0

E-PlaneH-PlaneHPBWE = 37.1

o

434 Mhz 0

30

60

90

120

150180

210

240

270

300

330

-25 -20 -15 -10 -5 0-25

-20

-15

-10

-5

0

-25-20-15-10-50-25

-20

-15

-10

-5

0

E-PlaneH-PlaneHPBWE = 36.1

o

438 Mhz 0

30

60

90

120

150180

210

240

270

300

330

-25 -20 -15 -10 -5 0-25

-20

-15

-10

-5

0

-25-20-15-10-50-25

-20

-15

-10

-5

0

E-PlaneH-PlaneHPBWE = 36.5

o

Radiation Patterns at UHF Band

3D Radiation Pattern at 438 MHz 13

Realized gain (dB)

Frequency (MHz)100 200 300 400 500

(dB

)

-10

-8

-6

-4

-2

0

2

4

6

Ant. Vesion 1.0Ant. Vesion 2.0

The total realized gain of the antenna Version 2.0 at 146 MHz and at 438 MHz is greater than the antenna Version 1.0 about 0.5 dB and 1.0 dB, respectively.

Realized Gain Comparison

14

Prototype #1

15

Thespring-steelantennaelements

Theantennamount

SMAconnectorTeflonclampparts

Spring steel loops problem, when the twoloopsa\achedtothemainmonopoleantennacreates a\enXon at the a\ached pointscausedbending.

16

Reflection Coefficient

Frequency (MHz)100 200 300 400 500

S 11

(dB)

-40

-30

-20

-10

0

MeasuredSimulated (CST)

BW < -10dB

Prototype #2 and Preliminary result

SoluXon:Replacingthetwoloopsofspring-steelwithlightandflexiblesteelwire.

Flexible steel wire

Spring-steel

DeployableMonopoleAntenna

Summary

17

•  A new Dual-Band VHF/UHF monopole with double loopantennafornanosatelliteapplica3onsispresented.

•  The monopole antenna employs double loop to op3mizeand to tune the matching impedance of dual-bandindividually.

•  TheantennaV2.0 realizedgain isaround2dBat146MHzand3.85dBat438MHz.

•  TherealizedgainoftheantennaV2.0at146MHzandat438MHzisgreaterthantheantennaV1.0about0.5dBand1.0dB,respec3vely.

•  ThisnewdesignmodelispreferableforreducingthereturnlossandincreasestheHPBW.

•  The antenna characters make it as a good candidate fornanosatelliteLEOrangecommunica3on.

Thank You

18

Our Sponsors: