All things DBE…Francois Kapp

Sub-system Manager: DBEFrancois.kapp@ska.ac.za

On behalf of the DBE team present and past...S Rajan, E Bauermeister, A Rust, L Sofeya, P Gibbs, S Malan, W New, R van Rooyen, A Barta, A Martens, J

Manley, P Prozesky, V Moss, D George

What we do…

Outline

• Context• CASPER

• HW Tools• SW Tools• Community

• KAT-7• KAT-7 DBE

• MeerKAT• MeerKAT Requirements• MeerKAT System Architecture Aspects• MeerKAT Cost• MeerKAT Schedule

Context

• We are engineers…

Context

• We use acronyms like:• PCB, FPGA, ROACH, MSSGE, PFB, ADC, DBE…

Context

• We typically add them together…

+ =

+ =

Context

• and we keep doing this…

+

=

Context

• And sometimes we use multiplication…

16 x=

• CASPER – Collaboration for Astronomy Signal Processing and Electronics Research

• Started at U.C. Berkeley• Trying to create the “PC” of RA• Re-configurable computing• Use low cost commodity hardware

(common to many observatories)• Develop few platforms quickly• Upgrade often• Accelerate the application development

CASPER

CASPER Generic Architecture

ROACH

CASPER and ROACH

CASPER, ROACH and MIC?

ROACH in the future

CASPER SW/FW/GW Tools ..1

• MSSGE Toolflow• Matlab/Simulink/System Generator/Embedded Development Kit• But…

• Current Matlab/Simulink tool-flow is becoming unstable and is not scaling well with FPGA size -> we need a new solution

• MyHDL: Python based tool to simulate python code and convert it to Verilog or VHDL

• Designing a set of DSP libraries using combination of Verilog and MyHDL (Python)

• Implementing a Python framework to manage design simulation and synthesis of Radio Astronomy Instruments on FPGA hardware

• Wesley New - poster

CASPER SW/FW/GW Tools ..2

• SPEAD• Streaming Protocol for Exchange of Astronomical Data• High “speed” data protocol• https://casper.berkeley.edu/wiki/SPEAD

• KATCP• A text based language for devices on the KAT network• Now: ?request, !reply, #inform• Future: would like to describe complex tasks in KATCP fashion

• Need: • A way to describe tasks (statemachines)• An Interpreter• Sets of modules containing operations and conditions

• Meet ?sm – Adam Barta to handle a proper introduction – poster

CASPER SW/FW/GW Tools ..3

• BORPH• Berkeley Operating system for ReProgrammable Hardware• http://www.eee.hku.hk/~hso/borph.html

• Corr – Python library for CASPER packetised Correlators• Linux Driver work

• Automated Gateware Discovery Using Open Firmware• Research framework to describe FPGA designs, facilitate

detection by OS, interaction using conventional device drivers.

• Specific to KAT digital backends • Provides an alternative approach to reduce time and effort

spent on writing software for each piece of gateware generated

• Shanly Rajan – talk

• https://casper.berkeley.edu/• Workshops, mini workshops, mailing lists and friendly ghosts

CASPER Community

KAT-7 ASC

22

Inside KAT-7 ASC

Network Switch

Fibre Patch Panels

RFE Stage 7

DBE ROACH Board

CSS Sun Servers

GPS Rubidium Clock

KAT-7 DBE

MeerKAT

MeerKAT – PhasesPhase 1

(current planning)Phase 2

Estimated completion date 2016 2018

Frequency bands (GHz) 1-1.75 0.58 – 1.0158-14.5

RF bandwidth (MHz) 850 6500

Sampling frequency (GSPS) ~2 ~15?

Processed bandwidth (MHz) 850 6500?

Max baseline (km) 8 50?

• All current planning for phase1 – funded, well defined• Subsequent phases not finalized, but considered in design• Phase 2

• Added Receivers (frequency upgrade)• Added antennae (baseline upgrade)

MeerKAT Subsystems on antenna

Antenna structures

Receivers

Digitiser?

• Move the Digitisation up the signal chain and onto the Antenna (close to the feed)

• Feed selector• Sub-arrays mean that different

feeds can be selected on different antennae

• Signals transported to the KAPB digitally

• Time and Frequency References to be distributed

MeerKAT DBE

MeerKAT Digitiser

MeerKAT TFR

• Time and Frequency Reference Sub-system• Distributes a Reference Clock and Synchronisation Pulse• For phase 2:

• Must compensate for thermal and mechanical effects in fibre• Buried 1m deep, but exposed at antenna• Cable wrap effects• Measure round-trip phase• Compensate by controlling clock phase or in correlator

Site

Com

plex

Upgra

de

MeerKAT DBE Cost

MeerKAT DBE Cost ..2

MeerKAT Schedule

MeerKAT Schedule

• 2013 – Dish 1• Start with ROACH2 based test system, prototype Digitiser• Build up to:

• 5 (end 2014, ROACH2)• 20 (end 2015, ROACH2)• Full 64 (2016, ROACH3)

• ROACH3 into production – 2013• Final Digitiser Qualification 2013• System acceptance end 2016• And then there’s phase 2...• And SKA?