A digital beamformer for the advanced focal array demonstrator (AFAD)

Stephen T. Harrison; Gary J. Hovey; Bruce Veidt; Zoran Ljusic; Tom Burgess

doi:10.1117/12.2311504

9 July 2018 A digital beamformer for the advanced focal array demonstrator (AFAD)

Stephen T. Harrison, Gary J. Hovey, Bruce Veidt, Zoran Ljusic, Tom Burgess

Proceedings Volume 10708, Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX; 1070834 (2018) https://doi.org/10.1117/12.2311504
Event: SPIE Astronomical Telescopes + Instrumentation, 2018, Austin, Texas, United States

Abstract

Phased array feeds (PAFs) are an active research area in radio astronomy, as they offer potential advantages over traditional single-pixel feeds. Their key advantage is increased field of view and survey speed, however they also permit tailoring the antenna beam for A_e=T_sys, or other objectives such as attenuating strong radio frequency interference (RFI). A primary research goal is to improve the noise temperature performance of a PAF over comparable single-pixel feeds.

In this work we have constructed a small 16-element digital beamformer with 384 MHz of bandwidth to evaluate the performance of NRCs Advanced Focal Array Demonstrator (AFAD) operating from 750 to 1500 MHz. We compare measured sensitivity results to previous measurements made with an analog beamformer. The digital beamformer is implemented using NRCs Kermode platform, a Virtex6-based compute blade. We take a standards-based approach, using the AdvancedTCA (ATCA) form factor for the Kermode board, ANSI/VITA-49.0 framing for all chip-to-chip and chip-to-host communications, and AXI4-Stream format for all internal datapaths. The Kermode system can be expanded with a standard ATCA full-mesh backplane to support up to 128 inputs with over 1 GHz of bandwidth.

This expanded capability will ultimately be used to evaluate the performance of the full 96-element AFAD PAF mounted on a re ector antenna. To achieve this goal, we are well into developing a digitizer system that will handle at least 96 elements with up to 1.5 GHz of bandwidth per element. We present an overview of the digitizer system in the context of the PAF beamformer system, and provide an update on the progress to date.

Citation Download Citation

Stephen T. Harrison, Gary J. Hovey, Bruce Veidt, Zoran Ljusic, and Tom Burgess "A digital beamformer for the advanced focal array demonstrator (AFAD)", Proc. SPIE 10708, Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX, 1070834 (9 July 2018); https://doi.org/10.1117/12.2311504

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available