1. An Instrumental test observation for 22GHz and 43GHz quasi-optical circuit of KVN receivers March 18 th 2009 Seog-Tae Han, Jung-Won Lee, Jiman Kang, Sang-Sung Lee, Do-young Byun, Do-Heung Je, Moon-Hee Chung, Seog-Oh Wi.

2. Outline - Eevaluation of Quasi-optical circuit for 22GHz and 43GHz bands - Test observation for quasi-optics circuit - Summary

3. Total Quasi-optical Circuit Evaluation for 22GHz and 43GHz bands Outline(I)

4. ( 단위 : 백만원 ) Quasi-optical circuit for Multi-band receivers

5. ( 단위 : 백만원 ) Frequency (GHz) Loss (dB) Cross- Pol. (dB) Beam Deviation (mm) LPF1Transmission220.2 35 <1mm 430.2 35 <1mm Reflection860.230<1mm 1290.130<1mm LPF2Transmission 220.230<1mm Reflection430.235<1mm LPF3Transmission860.130<1mm Reflection1290.130<1mm It took about more than 4years for design and test Good results to be used quasi-optical components Summary of the experimental results of LPFs

6. ( 단위 : 백만원 ) 22/43GHz band Quasi-optics circuit for simultaneous observation.

7. ( 단위 : 백만원 ) HPBW at Cass. focus @ 43GHz : approx. 30mm @ 22GHz : approx. 60 mm Beam Deviation between two beams : less than 1mm Beam deviation 22/43GHz for total Q.O circuit Red : 22GHz Green : 43GHz

8. ( 단위 : 백만원 ) Cass. focus Comparison between theoretical and measured beam size at cassegrain focus

9. ( 단위 : 백만원 ) Beam radii near Cass. focus at 22GHz 2mm (2/50) difference Without LPFWith LPF 49.4mm 47.6mm (Transmission through LPF2)

10. ( 단위 : 백만원 ) 2mm ( 2/26.4 ) difference Without LPF With LPF 26.4mm24.5mm Beam radii near Cass. focus at 43GHz (Reflection by LPF2)

11. ( 단위 : 백만원 ) w0a=3λ Woa/Wob : 26.5/24.7 @ 43GHz : 49.5/47.4@22GHz 1.05 both 22/43GHz Beam coupling loss due to mismatch both 22/43GHz apporxi. less than 1% Evaluation axial beam mismatch between theo. and exp.

12. LPF Loss Measurement Setup

13. The additional Receiver Noise Temperature Due to the LPFs

14. ( 단위 : 백만원 ) Quasi-optical circuit for Multi-band receivers

15. ( 단위 : 백만원 ) Quasi-optical circuit at Lab LPF1 LPF2 LPF3 M1 M2 M3 Flat M Horn 22G M4 Flat M M5 Cal chopper

16. ( 단위 : 백만원 ) Quasi-optical circuit installed at receiver room of antenna Quasi-optical circuit installed at receiver room of antenna M5 Cal chopper 22GHz RX 43GHz RX M4 M1 M2 M3

17. Outline(II) Test observation for Evaluation of Quasi-optics Circuit

18. Contour Map of Jupiter for 22GHz and 43GHz bands

19. 22GHz ( Red ) 43GHz ( Black ) Bold lines show HPBW

20. 22GHz ( Red ) 43GHz ( Black ) The Pointing offset between 22GHz and 43GHz band at Jupiter October 28 th 2008

21. 43GHz ( Black ) The Pointing offset between 22GHz and 43GHz band at Jupiter 22GHz ( Red ) March 6 th 2009

22. Radiation patterns of Jupiter for 22GHz and 43GHz bands

23. Orion-KL H 2 O and S i O Maser Line Simultaneous Observation Results !!!!! on October 28 th 2008

24. Aperture efficiencies at 22GHz/ 43GHz Efficiency (%) EL (°) RemarkT B * (K) Aperture efficiencies at 22GHz Venus68(70)30LPF2505+-25** Aperture efficiencies at 43GHz Venus68.8(70)32LPF2450+-32

25. Summary  Pointing offset between 22GHz and 43GHz - less than 1” ( Pointing error of KVN antennas : 4”)  Successfully done simultaneous observation - 22GHz and 43GHz bands  Aperture efficiency 68%(70%) at both 22/43GHz  Quasi-optical evaluation for 86GHz and 129GHz - must be harder than that of previous ones  Development of 86GHz and 129GHz receiver optics - at least 2011.

26. Thanks for your attention