Instrumentation for the Effelsberg 100-m Telescope Max-Planck - - PowerPoint PPT Presentation

Instrumentation for the Effelsberg 100-m Telescope

Max-Planck Institut für Radioastronomie Presented by Gundolf Wieching 21.02.2018

100 m Effelsberg Telescope

• Inauguration: May 12, 1971

– Regular operations started on August 1, 1972

• Aperture: 7854 m2, Sensitivity > 1.5 K/Jy (≤ 20 GHz)
• Surface accuracy: ~0.5 mm
• Frequency coverage: 300 MHz – 90 GHz
• Resolution:

– 9’ @ 1.4 GHz – 10” @ 86 GHz, pointing accuracy ~2-3”

• Optics: Gregorian
• Homology structure
• Observing modes:

– continuum, – spectroscopy, – pulsars & transients, – VLBI (European, global, mm)

06.09.2016 TVN 2016

Effelsberg Instrumentation Overview

Receiver Abbr. RF start GHz RF stop GHz RF-BW GHz IF-BW GHz Channels

• No. of

beams Installation date

50cm P500 0,3 0,9 0,6 0,6 LCP/RCP 1 2011 PAF 0,7 1,7 0,4 0,3 H/V 37 2017 30cm (UHF) P300 0,8 1,3 0,5 0,1 LCP/RCP 1 1999 L-Band 7 Beam P217 1,3 1,6 0,3 0,3 LCP/RCP 7 2005 18/21cm P200 1,3 1,8 0,5 0,1 LCP/RCP 7 2006 UBB P170 0,6 3 2,4 2,4 H/V 1 2012 13cm S130 2,2 2,3 0,1 0,1 LCP 1 2004 11cm S110 2,6 2,7 0,1 0,1 LCP/RCP 1 2002 9cm P90 2,9 3,6 0,7 0,1 LCP 1 1985 6cm S60 4,6 5,1 0,5 0,5 LCP/RCP 2 1995 5cm P50 5,8 6,8 1 0,5 LCP/RCP 1 2003 C+-Band S45 4 9,3 7,3 4 H/V 1 (2*) 2014 3.6cm S36 8 9,2 1,2 0,5 LCP/RCP 1 2004 2.8cm S28 10,3 10,6 0,3 0,1 LCP/RCP 2 1980 2.2cm P22 12,1 13,6 1,5 0,1 LCP/RCP 1 1990 Ku-Band* 12 18 6 6 LCP/RCP 2 2017* 2cm S20 14 16 2 0,5 LCP/RCP 1 1998 1.9cm P19 13,5 18,7 5,2 0,5 H 1 2000 K-Band S14 18 26,5 8,5 8,5 H/V 2 2013 1cm P10 27 38,7 11,7 2 H 1 1996 9mm S9 30 34 4 LCP/RCP/H/V 7 2008 Q-Band* 33 50 17 4 LCP/RCP 2017* 7mm S7 41,6 44,4 2,8 0,5 RCP 1 1998 3mm P3 84 96 12 2 LCP/RCP 1 1999

Frequency coverage

0,1 1 10 100

50cm PAF* 30cm (UHF) L-Band 7 Beam 18/21cm UBB 13cm 11cm 9cm 6cm 5cm C+-Band 3.6cm 2.8cm 2.2cm Ku-Band* 2cm 1.9cm K-Band 1cm 9mm Q-Band* 7mm 3mm

RF Frequency in GHz

Effelsberg Focus System

Primary Focus

Secondary Focus

Ultra-Broad-Band Receiver

Designed for Pulsar observations

• increase in bandwidth -> sensitivity
• Feed covers 0.6GHz – 3.0GHz
• RFI requires filtering
• Trec < 20K
• Baseband detection (1.3 – 2.6GHz)

600 800 1000 1200 1400 1600 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 frequency (MHz) time (sec) L-BAND L-BAND

PSR$B1933+16$

credit to Paulo Freire

K-Band 18 – 26 GHz Receiver

• Two feeds
• IF Modes:

– Mode I: LCP, RCP at two feeds 8 x 2.5GHz res: 45KHz – Mode II: LCP at one feed 28 x 300 MHz, res: 5.4 kHz – 4 GHz VLBI IF

K-Band IF modules K-Band synthesizer

K-Band 18 – 26 GHz Receiver

Sensitivity: Trec < 20K TSys < 55K (weather dominated)

C+-Band Receiver

Design Specifications RF frequency range 4.0 - 8.0 GHz 5.3 - 9.3 GHz number of feeds 1 (final implementation: 2) polarization linear polarisation, cross-polar. < -20 dB system sensitivity Trec: <20 K full band IFspectroscopic 4 x 2.5 GHz, res: 44.3 kHz (1.6 km/s @ 8 GHz) zoom IFspectroscopic 4 x 300 GHz, res: 5.3 kHz (0.29 km/s @ 8 GHz) IFgeneric/VLBI 2 x 0 – 4.0 GHz calibration source noise source, line source

Q-Band Receiver

Design Specifications RF frequency range 38 - 50 GHz feeds Dual cryogenic horn Polarization Circual polarisation cross-polar. < -20 dB System sensitivity Trec: < 45 K Full band IFspectroscopic 8 x 2.5 GHz, res: 44.3 kHz IFgeneric/VLBI 4 x 4.0 GH Calibration source noise source, line source

, instantaneous bandwidth 4x 4GHz ( 4 channels ) spectrometers possible

Ku- Band Receiver

Design Specifications RF frequency range 12.0 - 18.0 GHz number of feeds 2 corrugates horns polarization 2 x circular polarized (cross-pol. <-20dB) system sensitivity Trec: 20K full band IFspectroscopic 12 x 2.5GHz, res: 44.3kHz IFgeneric/VLBI 2 x 4.0GHz calibration source noise source, line source

Phased Array Feed (PAF) for Effelsberg

• Modified ASKAP PAF
• 188 dipole antennas

(94 per polarization)

• Frequency range 0.7GHz – 1.8GHz
• 300 MHz instantaneous bandwidth
• 36x2 independent beams
• Science commissioning Dec 2017

Xinping Deng et. al. IAU 2017

Band ASKAP (MHz) MPIfR (MHz 1 700-1200 700-1200 2 840-1440 1200-1480 3 1400-1800 1340-1740 4 600-700 600-700

Phased Array Feeds

• Massive digital beam forming allows to populate the FOV with individual

beams

– increases the survey capability of big single dish telescopes such as Effelsberg

• Nulling of RFI sources

– accessing “lost” frequencies

• Broad bandwidth
• Reduction of baseline variation due to standing waves
• Post detection beam forming e.g. for FRB search
• Sensitivity has to be compatible with single pixel receivers, approx. 20K/Beam
• > cryogenic PAFs
• cryoPAFs will help to secure the long-term sustainability of the telescopes by

– increasing the survey capabilities – reducing the impact of the increased RFI emission – introducing new generic design for various RF frequencies

Activities

Project B2: Development of cryogenic PAFs

– direct sampling, low power ADCs – development of cryoPAF design – assessment and implementation of requirements as variations for individual the telescopes e.g. for Effelsberg, FAST, QTT – design of low-loss transitions between antenna and LNAs – design, fabrication and measurements of a small-scale prototype of the integrated passive front-end unit – multifunctional cryogenic On-Chip Integration of e.g. LNA, RF-switches, broadband amplifier, phase shifter – ryogenic cooling and mounting concept for e.g. of Antennas, LNAs, Windows, IR filters etc. – digital beam forming concepts, simulation and implementations – evaluation on efficient RFI mitigation algorithms

Supporting Infrastructure

• RFI tight supporting infrastructure

– receiver control and monitor system – time distribution – RF over fibre system – IF switching system – Total Power Backend

• –

“Clipboards”

: InteRCoM 19‘‘

InteRCoM GUI

Spectropolametrie Backend

Receiver OMT ADC0 ADC1 FPGA Stokes Parameter computation 10GbE Server IF channel IF channel I,Q,U,V I,Q,U,V

Specpol

Blank/Sync signal

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Requirements for new receivers

• Increase efficiency

– increase of sensitivity – increase stability – increase number of pixels/FOV coverage – increase bandwidth(?)

• Adapt to RFI increase

– increase of dynamic range – RFI mitigation technics

• Reduction of maintenance effort

– reduction of receiver system – use of COTS components, e.g. networking, computing

Rx design

OMT Hybrid Dewar IF Processor Optical Transmitter Optial Receiver IF Processor

• Spec. (incl. ADC)

Pulsar (incl. ADC) VLBI (incl. ADC) Polarimetry Frontend IF System Backend

Future Rx

OMT Hybrid Dewar IF Processor Optical Transmitter Optial Receiver IF Processor

• Spec. (incl. ADC)

Pulsar (incl. ADC) VLBI (incl. ADC) Polarimetry Frontend IF System Backend

Future RX

OMT Dewar ADC Ethernet Switch Spec. Pulsar VLBI Polarimetry Frontend Digitizer Backend FPGA IF Converter

Ø reduced analogue parts Ø digital interfaces Ø higher () stability Ø expandable Ø industrial standard Ø reduced cost (capital and operational) Ø increased flexibility

MPIfR MeerKAT S-Band Frontend

11.01.2017 Lunch Talk MPIfR

Frontend Specifications Number of Rx 2 prototypes (spare) 64 production Rx Bandwidth 1.75 - 3.50 GHz Digitizer Bandwidth 1.75 - 3.50 GHz (12 bit) Backend Interface 40 GB Ethernet, SPEAD protocol Sensitivity Tsys < 25 K Stability spectroscopic Allan time(1 MHz Bandwidth) > 1000 sec. Polarisation H and V polarisation, cross coupling < 20 dB System Setup cryogenic Dipole and LNA @ 15 Kelvin GM cooler baseband digitizing @ receiver Additional Requirements highly reliability maintainability weight limit 65kg integration in MeerKAT infrastructure and maintenance plan Operating temperature 0 - 40DegC full-fill MeerKAT RFI requirements

MPIfR Backend Concept

Beamformer 32-nodes 2x Titan X (pascal) 2x 40 GbE NIC 512 GB RAM

Antenna data

FRB Search 66-nodes 2x Titan X (pascal) Pulsar Search 50-nodes 2x Titan X (pascal) 2.2 PB storage

credit E. Barr

Upcoming Systems

• Systems for Effelsberg

– Q-Band Receiver (33-50GHz) – Ku-Band Receiver (12-18 GHz) – UBB Upgrade (1.3-2.6 GHz) – Ka-Band Receiver (26.5-40GHz) – BRoad-bAND EVN (Brand) Receiver (1.5-15 GHz) – Cryogenic PAF (high S-Band? tbc) – Generic Backend incl. direct digitization

• MeerKAT S-Band Receiver System
• SKA Prototype Antenna

– workshop "Science with the MPIfR-MT SKA Prototype Telescope“, 16th of April 2018

Many thanks to all involved!