Future Radio Frequencies and Feeds Wettzell / Hoellenstein (Germany), Development … ·  ·...

IVS VLBI 2010 Workshop on

Future Radio Frequencies and Feeds

Wettzell / Hoellenstein (Germany),

March 18 - 20, 2009

Development of a Compact VLBI System for

Providing over 10-km Providing over 10-km Baseline Calibration

Ishii A.(1),(2),(3), ICHIKAWA R.(1), Takiguchi H.(1),

Kuboki H. (1), Kimura M. (1), Nakajima J. (1), Koyama

Y. (1), Kondo T. (1), Machida M. (2), Kurihara S. (2), Y. (1), Kondo T. (1), Machida M. (2), Kurihara S. (2),

Kokado K. (2), and Matsuzaka S. (2)

(1) Kashima Space Research Center, NICT(2) Geographical Survey Institute

(3) Advanced Engineering Services Co.,Ltd.

Contents

• Objective

•• Observation Concept

• First Prototype of Compact

VLBI System

• First VLBI Experiments

2/20

• First VLBI Experiments

• Second Prototype

• Summary & Outlook

First Objective:First Objective:

Baseline Calibration

for GPS and EDM

SurveySurvey

Rover VLBI measurements are also available.

GSI Baseline Calibration Site

ReferenceReferenceBaseline(~10 km)

Tsukuba City

GSI

Observation

Concept

Station R(Large Antenna)

Correlation Processingis performed

No Correlation Processing

Calibration Baseline(~10 km)

Station YStation X

GPSVLBIGPS

VLBI

RX

XY

RY

Station Y(Compact Antenna)

Station X(Compact Antenna)

XY = RY - RX

Multiple Antenna Radio-interferometry

Baseline Length Evaluation

of

MARBLE

M A

B L E

R

MARBLESystem

Development

ofof

MARBLE

CompactCompact

VLBI System

Specifications of MARBLE

Compact VLBI Antenna

• Diameter: 1.5 – 1.8 m• Diameter: 1.5 – 1.8 m

• Feed Location: Primary Focus

• Mount: AZ/EL

• AZ/EL Slew Speed: > 5deg/sec

9/20

• AZ/EL Slew Speed: > 5deg/sec

• Transportability: The system is designed to be assembled with

muscle power.

Transportability of

MARBLE Compact VLBI

System

VLBI measurement

AZEL

Dish

AZELACU

DC

GPS measurement

Pillar

AZ

ACU

DCAZELACU

Prototype of Prototype of

MARBLE

Compact AntennaCompact Antenna

First Prototype

First Prototype (cont’d)

First Prototype (Front end)

Band-width of LNA1-11GHz

Feed: Quad-ridge Horn

Antenna [QRHA]

• ETS/LINDGREN 3164-05• ETS/LINDGREN 3164-05

• 2 GHz - 18 GHz Frequency Range

• Dual linear polarized

• weight: 0.7 kg

15/20

• weight: 0.7 kg

• size: 17.1 X 17.1 X 18.6 [cm]

Anechoic Chamber Test

S-band

X-band

First Fringe DetectionFeb. 12, 2009

ACUFS9

X-band

S-bandACU S-band

Fringe detection using ADS3000+ was also successful.

Second Prototype

•Dish Diameter: 1.5m•F/D: 0.49 (1 : •F/D: 0.49 (1st:

0.45)•Light Weight•100V AC power

1.5m

•100V AC power• The first prototype

needs 200V power supply.

Summary of

Present Status

• First Prototype is now available.• First Fringe Detection was performed

successfully on Feb. 12, 2009.•• Second Prototype is under development.

Outlook

• Second Prototype will be installed in GSI, • Second Prototype will be installed in GSI, Tsukuba.

• Geodetic VLBI Experiments using 1st and 2nd Prototypes are planned in the next fiscal year.

•next fiscal year.

• MARBLE Concept is under evaluation.• Local tie experiment is planned.