Dual-Band VHF/UHF Monopole with Double Loop Antenna for Nanosatellites

Transcription

1 Dual-Band VHF/UHF Monopole with Double Loop Antenna for Nanosatellites Zouhair Briqech, Kenton Neustaeter, Mariya Krasteva, Emmanuel Papanagiotou, Jan Clarence Dee, and Abdelrazik Sebak Space Concordia, Concordia University, Montreal, QC, Canada h"p:// CSCA 216 Toronto, ON, Canada February 2-3, 216 1

2 Outlines! Aleksandr s Antennas! Communica3on System Diagram! Dual-Band VHF/UHF Monopole Antenna! Dual-Band VHF/UHF Monopole with Double Loop Antenna! Parametrical Studies! Radia3on PaGerns! Realized Gain Comparison! Prototypes and preliminary result! Summary 2

3 Aleksandr s Antennas Version 1. Dual-Band VHF/UHF Monopole Antenna Version 2. Dual-Band VHF/UHF Monopole with Double Loop Antenna 3

4 Communication System VHF/UHV Antenna [*] Central Processor Helium 1 Transceiver R x T x Diplexer 438 MHz 146 MHz Deployable Monopole Antenna [*] T. F. C. Leao,, V. M. Chopin, Ch. W. Trueman, and S. Gleason. "Design and ImplementaXon of a Diplexer and a Dual- Band VHF/UHF Antenna for Nanosatellites." Antennas and Wireless PropagaXon Le\ers, IEEE 12, pp , 213 4

5 Dual-Band VHF/UHF Monopole Antenna 438 MHz 146 MHz 5 L = 45 mm L = 5 mm L = 55 mm L= 6 mm L = 65 mm L = 7 mm S11 (db) -1 L -2 6 mm mm 45 mm Frequency (MHz) The current density magnitude on the antenna element at 146MHz is a λ/4 standing wave, and at 438 MHz is a 3λ/4 standing wave. 5

6 Dual-Band VHF/UHF Monopole with Double Loop Antenna 438 MHz 146 MHz L c r b v b L a r c L c k b g b v c Isolators g c k c Calculation Software Tool: Computer System Technology Microwave Studio (CST MWS) based on finite integration technique (FIT) in time domain Z in 6

7 Parametrical studies S11 (db) La = 51 mm La = 528 mm La = 546 mm La = 564 mm La = 582 mm La = 6 mm L a Frequency (MHz) Increasing the L a leads to decreasing the main center frequency of the VHF and UHF band. 7

8 Parametrical studies (cont.) S11 (db) VHF - band Z b = mm Z b = mm Z b = mm Z b = mm Z b = mm UHF - band Z b mm Frequency (MHz) Changing Z b the large loop position has an effect on the antenna matching bandwidth at VHF band, while it has no varying impact on UHF band. 8

9 Parametrical studies (cont.) L b S11 (db) L b = 393 mm L b = 49 mm L b = 434 mm L b = 467 mm L b = 55 mm L b = 547 mm Frequency (MHz) Changing L b the length of large loop has an effect on the antenna matching bandwidth at both VHF band and UHF band. 9

10 Parametrical studies (cont.) UHF - band S11 (db) Z c = 125 mm Z c = 1 mm Z c = 75 mm Z c = 5 mm Z c = 25 mm Z c = mm 14 mm + Z c Frequency (MHz) Changing Z c the small loop position has an effect on the antenna matching bandwidth at UHF band, while it has very small impact on VHF band. 1

11 Parametrical studies (cont.) VHF - band UHF - band S11 (db) L c = 149 mm L c = 164 mm L c = 181 mm L c = 21 mm L c = 223 mm L c = 251 mm L c Frequency (MHz) Changing L c 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. 11

12 Radiation Patterns at VHF Band Mhz Mhz 3 3 HPBW E = 81.2 o E-Plane H-Plane HPBW E = 8.8 o E-Plane H-Plane Mhz HPBW -2 E = 8.3 o -1 E-Plane H-Plane D Radiation Pattern at 146 MHz 12

13 Radiation Patterns at UHF Band Mhz Mhz E-Plane -2 HPBW H-Plane E = 36.1 o E-Plane -2 HPBW H-Plane E = 36.5 o Mhz HPBW E = 37.1 o -1 E-Plane H-Plane D Radiation Pattern at 438 MHz 13

14 Realized Gain Comparison 6 Realized gain (db) 4 2 (db) Ant. Vesion 1. Ant. Vesion Frequency (MHz) The total realized gain of the antenna Version 2. at 146 MHz and at 438 MHz is greater than the antenna Version 1. about.5 db and 1. db, respectively. 14

15 Prototype #1 Teflon clamp parts SMA connector The antenna mount The spring-steel antenna elements Spring steel loops problem, when the two loops a\ached to the main monopole antenna creates a\enxon at the a\ached points caused bending. 15

16 Prototype #2 and Preliminary result SoluXon: Replacing the two loops of spring-steel with light and flexible steel wire. Spring-steel Flexible steel wire Reflection Coefficient S11 (db) -1-2 BW < -1dB -3 Measured Simulated (CST) Frequency (MHz) Deployable Monopole Antenna 16

17 Summary A new Dual-Band VHF/UHF monopole with double loop antenna for nanosatellite applica3ons is presented. The monopole antenna employs double loop to op3mize and to tune the matching impedance of dual-band individually. The antenna V2. realized gain is around 2 db at 146 MHz and 3.85 db at 438 MHz. The realized gain of the antenna V2. at 146 MHz and at 438 MHz is greater than the antenna V1. about.5 db and 1. db, respec3vely. This new design model is preferable for reducing the return loss and increases the HPBW. The antenna characters make it as a good candidate for nanosatellite LEO range communica3on. 17

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