RadioAstron Monthly Notices

July-August 2003

 

Tasks and developments completed in the ASC

 

1.       Monitoring of the development of the on-board 92-cm receiver (R-SRT-92 cm) ongoing at the KB GORIZONT in Nizhnii Novgorod:

a)       Printed-circuit plates for the flight model were manufactured and assembled;

2.       Monitoring of the development of the on-board 1.35-cm receiver (R-SRT-1.35 cm) ongoing at the OKB IRE in Fryazino:

a)       Development of the programs and the methods of the receiver tests were continued, namely:

ž         Specifications on the reliability test;

ž         Specifications on the control checks;

ž         Plan of the constructive rework;

ž         Plan of the integrated tests;

b)       Technical specifications on the secondary power supply unit were approved; constructive documentation on the device was created, the mockup was manufactured and tested in the laboratory.

3.       SRT test sets were delivered to LA and used for the checkout of the engineering models in assembled configuration as 'open' complex.

4.       Adjusting and testing of Formatter blocks (input quadrature convertor - heterodyne frequency selector and digital processing and forming blocks) were going in July-August. The positive results were obtained in digital SSB conversion and filtering.

5.       Formatter EGSE was tested in SRT configuration in LA

6.       Kalyazin 64-m radio telescope, the main Russian ground telescope for the RadioAstron project ,was equipped with the new 18-cm dual-polarization feed and receiver. Initial tests carried out in July 2003 showed that the telescope efficiency is close to 0.5, and the system temperature is 75 K, with the uncooled LNA temperature of 35 K.

 

Tasks and developments completed in Lavochkin Association

 

a.       All engineering devices delivered from the ASC were assembled and successfully checked as 'open' complex.

 

b.       Now all engineering models of scientific equipment are being assembled in standard flight configurations for the final check before delivering the assembled configuration to Pushchino.

 

c.       Thermal tests of special ground receiver cooling system (NSOTR) were successfully accomplished. NSOTR will be used in Pushchino to cool on-board receivers..

 

d.       Report on the accuracy of orbit measurements and orbit prediction has been issued by the Institute of Applied Mathematics under contract with LA for RadioAstron high orbit.

 

Appendix - the list of used acronyms

 

ASC Astro Space Center of Lebedev Physical Instutute

Cold Plate cooled LNAs and antenna feed

DC hermetic device container (part of payload); it contains Formatter, Rb oscillators,

synthesizer, control unit and is placed under dish

DM Device Module = DC + H-maser

EGSE Electronic Ground Support Equipment

Electronic Complex - all SRT electronics

 

EM Engineering Model

FC Focal Container - hermetic package with the scientific payload; it contains receivers,

microwave synthesizer, control unit and is placed in focal site of dish

FM Focal Module = Focal Container+Cold Plate

LA Lavochkin Association

OHCFS-SRT Space Radio Telescope On-board Heterodyne and Clock Frequency Synthesizer set

OHFS-SRT Space Radio Telescope On-board Hydrogen Frequency Standard

ORFS-SRT Space Radio Telescope On-board Rubidium Frequency Standard

Service Module, Spacecraft bus - spacecraft itself (without payload).

SRT Space Radio Telescope (all scientific payload including 10-m dish)

TMS Spacecraft Telemetry System (technical)

TVT Thermo-Vacuum Tests

VIRK Scientific high rate (up to 2x72 Mbit/s) radio complex, including transponder

ZBIT Zero Baseline Interferometer Tests (ZBIT)