1 / 14

Evolution of the 2-PAD Front-End

This document presents the latest developments in the 2-PAD front-end system, focusing on its dual-polarization capabilities and applications within the SKA framework. The paper, presented at the 3rd SKADS Workshop in April 2008, highlights design improvements, including custom analog and digital chips, signal processing architecture, and challenges encountered during development. Key insights into RFI shielding, interconnect solutions, and upcoming revisions aim for enhanced functionality suitable for next-generation radio astronomy arrays.

elkan
Télécharger la présentation

Evolution of the 2-PAD Front-End

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. Oxford Astrophysics Jodrell Bank Observatory • Hamid Dabiri Khah • Kris Zarb-Adami • Mark Jones • Mike Jones • Peter Hastings • Sascha Schediwy • Andy Faulkner • Aziz Ahmedsaid • Chris Shenton • Georgina Harris • Richard Morrow • Tim Ikin Evolution of the 2-PAD Front-End 2-PAD: Dual-Polarisation All Digital Aperture Array (DS4T6) 3rd SKADS Workshop – April 2008

  2. 2-PAD Analogue Signal Path Bunker RFI Shield Custom Analog Chip Custom Digital Chip Ant. polarisation PCB Plug HSS interface 4 off Beamformer Processors Processor Switch Noise source 4-bit ADC PSU Beamformer Processor Beam combing Processor +ve Reg } 4 i/ps each ....... PCB Station processors Custom Analog Chip(s) ....... From other beamformer proc. Analog Twisted Pair PSU 4-bit ADC LNA 256 elements x2 polarisations 128 analog i/ps Digital beams out 4 i/ps each ... Total 512 inputs ... Analog sig. conditioning control Control Processor Line Tx/Rx Station Control Buffers Time standard 3rd SKADS Workshop – April 2008

  3. Eventual Goal MMIC LNA 2-PAD Front-End Module Shielded Bunker Wall Front-End Module Line Driver LNA Amplification CoaxialCable TwisterPair ReceiverBoard Antenna Noise Diode Power Regulator 3rd SKADS Workshop – April 2008

  4. Previous Front-End Prototypes Gain Chain v1 Gain Chain v3 Gain Chain v2 Several Issues Identified! 3rd SKADS Workshop – April 2008

  5. Next Generation Front-End • Address identified issues, plus: • Dual-polarisation front-end module • Mass production plastic enclosure • Cheap metallisation of surfaces • Temperature stabilisation/cooling Still More Outstanding Issues! 3rd SKADS Workshop – April 2008

  6. Antenna Specific LNAs Embrace Tile Oxford Log-Period Dipole Flowpad 3rd SKADS Workshop – April 2008

  7. Output – Twisted Pair Cable • Coaxial cable problematic • Results in very high connector densities • Expensive • Twisted pair (CAT7) • Cheaper and more channels per area • Requires differential output 3rd SKADS Workshop – April 2008

  8. Current Front-End Version Antenna Specific LNA Quad Channel Amplifier Box Coax / Semi Rigid (~1m) CAT7(~20m) Amp2 Balun SMA Amp1 Amp3 TERA LNA Amp? SMA SMA 3rd SKADS Workshop – April 2008

  9. Conclusion and Further Work • First revision of current version nearing completion • We will continue to evolve the 2-PAD front-end until it reaches the functionality appropriate for the SKA 3rd SKADS Workshop – April 2008

  10. Gain Chain Versions 1 to 3 3rd SKADS Workshop – April 2008

  11. Gain Chain Version 4 Design • Commercial Front-end Module • http://www.nuwaves-ltd.com/pdf/uHILNA%20Data%20Sheet.pdf 3rd SKADS Workshop – April 2008

  12. Oxford Log-Periodic Dipole • Physical Properties • beam width: 22° (HPHW) • forward gain: 11.5dBi • low horizon side lobes • frequency range: 0.3-1.0GHz • return loss: better than −15dB 3rd SKADS Workshop – April 2008

  13. Oxford Log-Periodic Dipole forward gain simulation limitation cross-polarisation • Physical Properties • beam width: 22° (HPHW) • forward gain: 11.5dBi • low horizon side lobes • frequency range: 0.3-1.0GHz • return loss: better than −15dB 3rd SKADS Workshop – April 2008

  14. Complete Test Chain • Commercial LNA • (for testing this antenna only) Amplifier Box SignalConditioningModule 3rd SKADS Workshop – April 2008

More Related