Presentation is loading. Please wait.

Presentation is loading. Please wait.

S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 EVLA FEEDS DESIGN S. Srikanth NRAO/Charlottesville.

Published byClifton Trevor Blair Modified over 8 years ago

Similar presentations

Presentation on theme: "S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 EVLA FEEDS DESIGN S. Srikanth NRAO/Charlottesville."— Presentation transcript:

1 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 EVLA FEEDS DESIGN S. Srikanth NRAO/Charlottesville

2 VLA Cassegrain Geometry Drawing

3 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Current Receiver Bands

4 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 VLA Vertex Feed Cone

5 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 EVLA Receiver Bands

6 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Selection of Bands Minimize number of receivers Use existing technology Performance at the band edges - feeds, polarizers, amplifiers etc.

7 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Selection of Feed Type and Parameters Nominal taper of -13 dB at 9.25 degrees Compact horns where space is limited Ring-loaded slots (except for Q-band) Number of corrugations/wavelength - 3.8

8 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Conventional Corrugations

9 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Ring-Loaded Corrugations

10 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 VSWR – Conventional and Ring-Loaded

11 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002

12 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002

13 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002

14 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002

15 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002

16 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002

17 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Linear Taper Horn 75" OD – 1.0 GHz

18 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Linear Taper Horn 75" OD – 1.4 GHz

19 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002

20 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of 75" OD and 62" OD Feeds

21 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Compact Horn – 75" OD 1.0 GHz

22 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Compact Horn – 62" OD 1.0 GHz

23 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Compact Horn – 75" OD 1.4 GHz

24 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Compact Horn – 62" OD 1.4 GHz

25 VLA Cassegrain Geometry Drawing

26 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 ANALYSIS METHODOLOGY

27 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 ANALYSIS METHODOLOGY  =  /  max  =  /sin  max 6. Grids on the reflector surface

28 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of Subreflector Patterns at 1.5 GHz (  = 0°) JPL Software NRAO Software

29 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of Subreflector Patterns at 1.5 GHz (  = 90°) JPL SoftwareNRAO Software

30 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of Main Reflector Patterns at 1.465 GHz Measured NRAO Software - 4 -2 0 2 4

31 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 1.4 GHz Compact Horn - 75" OD Symmetric Plane

32 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 1.4 GHz Compact Horn - 62" OD Symmetric Plane

33 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 1.4 GHz Compact Horn - 75" OD Asymmetric Plane

34 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 1.4 GHz Compact Horn - 62" OD Asymmetric Plane

35 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 1.4 GHz Compact Horn - 62" OD Symmetric Plane

36 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 1.4 GHz Compact Horn - 62" OD Asymmetric Plane

37 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Main Reflector Pattern – 1.4 GHz Compact Horn - 75" OD

38 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Main Reflector Pattern – 1.4 GHz Compact Horn - 62" OD

39 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of 75" OD and 62" OD Feeds

40 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Compact Horn –75" OD

41 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Compact Horn – 62" OD

42 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of 75" OD and 62" OD Feeds

43 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of 75" OD and 62" OD Feeds

44 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison of 75" OD and 62" OD Feeds

45 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 The hybrid lens feed

46 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Measured Pattern – Current Feed

47 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Corrected Pattern – Current Feed

48 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Measured Pattern – Current Feed

49 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Corrected Pattern – Current Feed

50 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison: New Design & Current Feed L-Band

51 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison: New Design & Current Feed L-Band

52 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison: New Design & Current Feed L-Band

53 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison: New Design & Current Feed L-Band

54 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison: New Design & Current Feed L-Band

55 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison: New Design & Current Feed L-Band

56 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Comparison: New Design & Current Feed L-Band

57 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 3.0 GHz -11 dB Taper

58 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Subreflector Scatter Pattern – 3.0 GHz -18 dB Taper

59 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Gain/T sys Analysis

60 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Gain/T sys Analysis

61 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Gain/T sys Analysis

62 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 EVLA – Predicted Performance

63 S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 Future Work

Download ppt "S. SrikanthEVLA Feed/FE PDR February 12-13, 2002 EVLA FEEDS DESIGN S. Srikanth NRAO/Charlottesville."

Similar presentations

Chalmers University of Technology Development of a Coolable Decade Bandwidth Eleven Feed System for SKA & VLBI 2010 Radio Telescopes Per-Simon Kildal Chalmers.

Chalmers University of Technology Development of a Coolable Decade Bandwidth Eleven Feed System for SKA & VLBI 2010 Radio Telescopes Per-Simon Kildal Chalmers.
Microstrip Reflectarrays Myths and Realities JINA Conference David M

Microstrip Reflectarrays Myths and Realities JINA Conference David M
Nasimuddin1 and Karu Esselle2

Nasimuddin1 and Karu Esselle2
Rick PerleyEVLA Advisory Committee Meeting December 14-15, 2004 1 EVLA Hardware Testing Rick Perley With much essential help from Barry Clark, Ken Sowinski,

Rick PerleyEVLA Advisory Committee Meeting December 14-15, EVLA Hardware Testing Rick Perley With much essential help from Barry Clark, Ken Sowinski,
NRAO Receivers Richard Prestage

NRAO Receivers Richard Prestage
Compact and Spherical Range Design, Application and Evaluation Walter D. Burnside and Inder J. Gupta The Ohio State University ElectroScience Laboratory.

Compact and Spherical Range Design, Application and Evaluation Walter D. Burnside and Inder J. Gupta The Ohio State University ElectroScience Laboratory.
2001 APCO/NENA State Training Conference January 19, 2001.

2001 APCO/NENA State Training Conference January 19, 2001.
SIW 2003 The antenna element Ravi ATNF, Narrabri 1.The role of the antenna in a Fourier synthesis radio telescope 2.The Compact array antenna.

SIW 2003 The antenna element Ravi ATNF, Narrabri 1.The role of the antenna in a Fourier synthesis radio telescope 2.The Compact array antenna.
ALMA workshop - Leiden, December 18-20th ALMA Bandpass Calibration: Standing Waves Aurore Bacmann (ESO) Stéphane Guilloteau (IRAM)

ALMA workshop - Leiden, December 18-20th ALMA Bandpass Calibration: Standing Waves Aurore Bacmann (ESO) Stéphane Guilloteau (IRAM)
Satellite Communications A Part 2

Satellite Communications A Part 2
Twelfth Synthesis Imaging Workshop 2010 June 8-15 Antennas & Receivers in Radio Astronomy Mark McKinnon.

Twelfth Synthesis Imaging Workshop 2010 June 8-15 Antennas & Receivers in Radio Astronomy Mark McKinnon.
B-pol optical configurations Telescopes and Focal plane options B. Maffei for the B-pol collaboration G. Pisano A. Murphy T. Peacocke.

B-pol optical configurations Telescopes and Focal plane options B. Maffei for the B-pol collaboration G. Pisano A. Murphy T. Peacocke.
Lindgren Quadridge Feeds S. Weinreb and W. Imbriale SKA Antenna Working Group May 6, 2009.

Lindgren Quadridge Feeds S. Weinreb and W. Imbriale SKA Antenna Working Group May 6, 2009.
1 National Radio Astronomy Observatory EVLA Status -- Jim Ulvestad, for Mark McKinnon, Rick Perley, and the EVLA Team.

1 National Radio Astronomy Observatory EVLA Status -- Jim Ulvestad, for Mark McKinnon, Rick Perley, and the EVLA Team.
Technical University of Gdansk Department of Radio Communications

Technical University of Gdansk Department of Radio Communications
E. Szpindor, J. Ruff Advisory Committee Briefing June 10-11, 2002 1 Antennas and Feeds.

E. Szpindor, J. Ruff Advisory Committee Briefing June 10-11, Antennas and Feeds.
AuthorMeeting Title Date 1 EVLA Systems PDR Receivers/Feeds Daniel (Mert) MertelyEVLA System PDR:Receivers/Feeds 28 November, 2001.

AuthorMeeting Title Date 1 EVLA Systems PDR Receivers/Feeds Daniel (Mert) MertelyEVLA System PDR:Receivers/Feeds 28 November, 2001.
Antennas The primary elements of a synthesis array M. Kesteven ATNF 25/September/2001.

Antennas The primary elements of a synthesis array M. Kesteven ATNF 25/September/2001.
Tenth Summer Synthesis Imaging Workshop University of New Mexico, June 13-20, 2006 Antennas in Radio Astronomy Peter Napier.

Tenth Summer Synthesis Imaging Workshop University of New Mexico, June 13-20, 2006 Antennas in Radio Astronomy Peter Napier.
P.Napier, Synthesis Summer School, 18 June 2002 1 Antennas in Radio Astronomy Peter Napier Interferometer block diagram Antenna fundamentals Types of antennas.

P.Napier, Synthesis Summer School, 18 June Antennas in Radio Astronomy Peter Napier Interferometer block diagram Antenna fundamentals Types of antennas.

Similar presentations

Ads by Google