1 / 19

RFI in the alpha band pass Murray Lewis

RFI in the alpha band pass Murray Lewis. N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R. Senior Research Associate Radio Astronomy Group. Propose to cover. N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R.

amable
Download Presentation

RFI in the alpha band pass Murray Lewis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. RFI in the alpha band pass Murray Lewis N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R Senior Research Associate Radio Astronomy Group

  2. Propose to cover N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R FCC frequency allocations in spectral region GPS Galileo PR Radars in band RFI Mitigation possibilities radar blankers! nine level sampling! algorithms! cross correlation between feeds Reinforcement of AO anti-RFI activity!

  3. The frequency range covered by alpha is from 1225 to 1525 MHz N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R

  4. N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R

  5. N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R

  6. GPS L1, L2, L5 N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R L5 L2 L1 General coverage -158 dBW Spot Beam -138 dBW Alpha 1225 - 1525

  7. GPS N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R L1 & L2 -157 dBW for C/A -160 dBW for Y L5 -154 dBW ≈24 MHz, full time occupancy This is 6dB stronger than present L1 & L2 L5 spfd ~-205 dBW/m^2/Hz 1164-1188 MHz ~-197 dBW/m^2/Hz in center 5 - 8 satellites always available Also, of concern, GPS L3 circa 1381 MHz

  8. Galileo -- full set due 2008 N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R E5A_E5B 1164-1215 MHz (WRC2000) E6 1260-1300 MHz (WRC2000) E2,L1,E1 1559-1591 MHz Use of C_band under consideration To have 30 satellites, in 3 planes, inclination 56 deg 14 hr orbits, radius 23616 km Power 50 W amplifiers peak power 120 W

  9. Galileo N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R On orbit validation 2001-5 2/4 satellites Deployment 2006-7 26-28 sats Commercial Ops. 2008 Concern is their presence at 1260-1300 MHz

  10. N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R Details of Common/Unusual RFI Available on AO Web Page

  11. Hilltop Monitor 1200-1450 MHz N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R

  12. N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R Blanking San Juan Airport Radars? Examples Surroundings of 1400-1427 MHz band US has proposed a satellite system Uplink circa 1400, downlink circa 1427 MHz Timing explorer in Space Lab was at 1427 MHz L3 (GPS) at 1381 MHz

  13. Fractional occupation of 0.1 MHz bins N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R

  14. N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R

  15. 400 0 0 500 1000 1500 2000 RATAN-500 1116+28 20 0 0 500 1000 1500 2000

  16. Arecibo anti-RFI activity N A T I O N A L A S T R O N O M Y A N D I O N O S P H E R E C E N T E R importance of L_band to alpha Do you want radar blankers How bothersome is the 1350 MHz birdie? Should you be using 9-level sampling? Algorithm development

More Related