Road to MeerKATKAT-7 DBE

Alan Langman

meerKAT

Overview

• Objectives of meerKAT• Location Location Location• MeerKAT Engineering Specification• Prototypes to MeerKAT• KAT-7• Mention Control Interface• Other research• Questions?

Build a world class radio telescope (up to 80 dishes)Choose a frequency range that is likely to have high science impact. Commission a 7 dish system from end of 2009, engineering risk mitigation and do some early science.Train a new generation of scientists and engineers who are capable to participate in large international projects, such as the SKA. Provide an excellent facility for local and international scientists.Implement mission-driven innovation to mobilise industry, academia and research fraternity.SKA pathfinder

KAT/MeerKAT Objectives

SKA Bid - Remote site

The SKA & KAT site

South African Radio Frequency Measurement Campaign

Radio Frequency Environment HartRAO

MeerKAT SpecificationsParameter Minimum scenario Goal scenario

Frequency range 0.5-2.5 GHz 0.5 - 3 GHz

Expandable to include bands >8 GHz

Ae/Tsys 200 m2/K 300 m2/K

Feed & FoV Single-pixel wideband feed giving natural

primary beam FoV

Dish diameter 12 m

Number of dishes 80 100

Tsys 30 K 25 K

Array configuration 70% core array with 500m max. baseline.

30% extended array with 10km max.

baseline.

Instantaneous bandwidth 512 MHz 1024 MHz

Number of channels 16 k 64 k

Polarisation purity -25dB -25dB

Dynamic Range 50 dB

Phased array beams 5 > 5

MeerKAT DBE Functions

• Imaging (continuum + spectral line)• Beamforming(continuum + spectral line)• Pulsar Timing• Transient Detection• Baseband recording• VLBI• (and more … scope is still under revision)

Operations Centre(Cape Town)

Station Controller (Karoo)

Internet access

Front end station processor

Digital Receiver

Back end station processor

User (Scientist)

Optical RF links:80 x 2 optical links (80 dishes, 2 polarisations)

Station data:High speed, large data volume, long distance data transfer Karoo Station to off-site data processing facility.

Station data:Distribution internationally, typically over TCP/IP.

Key interfaces

Dishes and Feeds:80 x 12 m dishes, each equipped with a single pixel prime focus feed

What is the KAT/MeerKAT?

The prototyping phases

KAT-7 construction & commissioning

Experimental development model (XDM)

Phased Experimental Demonstrator (PED) 4x3x2 FPA

Completed

Current – at HartRAO

Current – at SAAO

On the proposed SKA site in Karoo – 2008 onwards

MeerKAT roll-out & commissioning

Same site in the Karoo – 2009 onwards

11 April 2007

Drift scan across Cygnus A

First extra-galactic object recorded by XDM – 17/07/2007

KAT-7

7

KAT-7 SpecificationsParameter Spec

Dish diameter 12 m

Number of dishes 7

Tsys 30 K

Frequency range 0.5-3 GHz

Array configuration < 100 m

Feed configuration Single pixel

feed, prime

focus

Instantaneous

bandwidth

256 MHz

Number of channels 16 k

MeerKAT DBE Functions

• Imaging (continuum + spectral line)• Beamforming(continuum + spectral line)• Pulsar Timing• Baseband recording• VLBI

KAT-7 Functional View

System health state displays

Radio sources

Task execution control

Task signal displays

Task definition

Task data products

Telescope

Data capturing machine

Task planning

tool

Post-processing

Task parameters

Raw data:(a i) Dish baseband(a ii) Tied-array baseband(a iii) Tied-array auto-correlation(b) Visibilities

Task instruction set

Task execution & resource

management

Modes:(a) Tied-array(b) Correlator

Task types:Single-dish tasks:- Single-dish tipping curve- Single-dish gain curve

Single-dish/tied-array tasks:- Tied-array operator control- Tied-array raw data capture- Tied-array spectroscopy- Tied-array pulsar monitoring- Tied-array pointing & gain measurement

Correlator tasks:- Gain&phase stability- Correlator operator control- Correlator raw data capture- Baseline calibration- Pointing calibration- Holography- Imaging

Operator

Observer

Operator

Task list

Raw data

Raw data Operator

Observer

- Tied-array displays- Correlator displays

Generate signal

displays

Operator

Task instruction set

Operator control(for manual tasks)

Task instruction set

Real-time (scan level) control

Contextual information

Generate system health

displays

Operator

Maintainer

RF in

Maintainer

Maintainer

KAT-7 Physical Architecure

ANTENNA SERVICES CONTAINER

Antenna Assembly (1 of 7)

Trench Trench

COMPUTING CONTAINER

CONTROL & MONITORING CONTAINER

Fibre

SITE COMPLEX

SW – LAN Switch n – (Antennas 1 to 7)VOIP – Voice Over IP terminalTRF – Time & Frequency ReferenceC&M – Monitor & Control PC – Personal Computer RF – Radio Frequency

Installation Interfaces

Key: Responsibilities

Telescope

Telescope

Ancillaries

Ancillaries

Infrastructure

Infrastructure

System Engineering Diagram seriesDiagram 3f: Installation Interfaces: Telescope to Ancillaries/Infrastructure25 June 2008

Fire SystemIntrusion SensorVOIP Point

Ancillary Equipment

C&M Network SW

C&M PC

Power System

Telescope Cabinet

C&M Network SW

Telescope Cabinet

Data Network SW

Fire System Intrusion SensorVOIP Point

Ancillary Equipment

Power System

TransformersUPS/DC SystemDiesel GeneratorPower Monitor

Fire Sensor

POWER ROOM

Shed

Network SW

Patch Panel

Fire SystemIntrusion SensorVOIP PointCCTV

Telescope Cabinet

Ancillary Equipment

Power SystemCooling Plant

Weather StationInterface Unit

Network SW

Antenna Drives

Antenna Controller

RF Stage 5

Heat Exchanger

Cooling Sensor

Ancillary Equipment

Power System

Telescope Cabinet

Cooling Splitter

Fibre

Accommodation

/3

/3

/3

Cooling Plant

ICD-M-01

ICD-M-05ICD-M-06

ICD-M-07

ICD-M-04

ICD-M-03

ICD-M-02

ICD-M-09

ICD-M-08

ICD-M-13

ICD-M-12

ICD-M-14

FEED ASSEMBLY

ICD-M-11

ICD-M-10

Operator Panel

Operator Panel

Cape Town Support Base

Carnavon Support Base

ICD-M-16

Air

Con

ditio

ner

Com

pres

sor

Air

Con

ditio

ner

Com

pres

sor

Network SW

Long distance Fibre Terminal Unit

SITE COMPLEX CONTAINER

DBE & RF Subsystem

Fire SystemIntrusion SensorVOIP Point

Ancillary Cabinet

ICD-M-15

BMS PC

Ancillary Equipment

TBD

DBE Architecture for KAT-7

Mechanical

Roach

katADC Requirements

• The katADC shall include an E2PROM to store configuration information.

• The katADC shall operate from 50MHz to 1GHz (goal 1.5GHz).

• The katADC shall sample data with more than 6.5 ENOB over the full operating frequency range.

• The katADC shall have a 50 ohm termination on the input, switchable via a suitable RF switch.

• The katADC shall have 30dB RF gain control• The katADC shall have an onboard PLL clock generator. • The katADC shall have RFI shielding.

katADC

Gateware/Firmware

• 100% CASPER tools• Developed Board Support Package for

ROACH• Integrated into toolchain• U-boot port on board• Ready for ROACH

Control / Monitoring

• Control interface are lines of text– Similar to tinysh, but with two differences:

• Syntax somewhat more formal, more amenable to machine parsing

• Not only set and get commands – commands defined for application domain (eg: start a data capture)

• In concept similar to a shell, but also SMTP, IMAP, POP, FTP

Implementation

• Runs out of FPGA blockrams on PPC• Control protocol runs over serial port• Multiple simultaneous data products over

network interfaces (100Mbit, 10Gbit):– Histograms (2 * 256 bins)– Radiometers (2 * integrated power value)– Spectrometer (1024 channels, IQUV

integrated)– Raw (2 * 1024 complex values)

Datastream control

• Create and destroy streams• Set up parameters for data products• Start and stop data streams• Data transfer

– High speed data products emitted autonomously by gateware over 10Gbit

– Lower bandwidth data products transferred by processor via 100Mbit interface

Example Command

• Broadcast histogram data for 15 seconds:• ?capture-create stream1• ?capture-source stream1 hist• ?capture-destination stream1

xdp1:192.168.20.255:7002• ?channel-dump-rate stream1 4• ?capture-start stream1 1194508376• ?capture-stop stream1 1194508391• ?capture-destroy stream1

Other control and monitoring

• Set time• Configure network interfaces• Dump and restore settings to survive

reprogramming• Report log events• ...

hiBOB (M. Aitken)

hubbleADC (J. Salkinder)

www.ska.ac.zawww.kat.ac.za

www.hartrao.ac.za