Possible Instrumentation Development Items for SKA at ASIAA Chau-Ching Chiong (ASIAA) and Yuh-Jing Hwang, Homin Jiang, Chao-Te Li

Outlines Back-end –ADC + ROACH –Fast Fourier Transform Spectrometer Front-end –Antenna, MMIC devices for SKA-mid : 500MHz -10GHz SKA-high : 10-25GHz Summary

AMiBA Backend Upgrade Digital backend using Gsps ADC + ROACH (Re-configurable Open Architecture Computing Hardware - a stand-alone FPGA processing board from CASPER) for molecular line observation, solve bandwidth smearing Wideband (2 GHz), high-resolution (2 MHz) digital correlator Integrate phase switching technique to reduce systematics cross power spectra with and without phase switching

LO2 + IF backend Additional LO (LO2) + IF circuits + Digital backend for AMiBA 2

5 Gsps ADC e2V 5Gsps chip 4 bits, demux 1:2/8 bits no demux 2GHz Bandwidth.Users: 1.UC Berkeley. USA 2.Green Bank, NRAO 3.SKA South Africa, South Africa. 4.University of British Columbia, Canada. CHIME project. 5.Haystack, MIT, USA 6.Smithsonian Astrophysical Observatory 7.Shanghai Observatory

4-bit LVDS/2.5GHz GTX Transceiver OSERDES 4-bit/1.25GHz D7 : D0 CLK D7 : D0 CLKDIV CLK OSERDES 4-bit/1.25GHz D7 : D0 CLKDIV CLK 4-bit LVDS/2.5GHz GTX Transceiver OSERDES 4-bit/1.25GHz D7 : D0 CLK D7 : D0 CLKDIV CLK OSERDES 4-bit/1.25GHz D7 : D0 CLKDIV CLK 4-bit LVDS/2.5GHz GTX Transceiver OSERDES 4-bit/1.25GHz D7 : D0 CLK D7 : D0 CLKDIV CLK OSERDES 4-bit/1.25GHz D7 : D0 CLKDIV CLK 4-bit LVDS/2.5GHz GTX Transceiver OSERDES 4-bit/1.25GHz D7 : D0 CLK D7 : D0 CLKDIV CLK OSERDES 4-bit/1.25GHz D7 : D0 CLKDIV CLK MMCM OSERDES 1-bit/1.25GHz D7 : D0 CLKDIV CLK OSERDES 1-bit/1.25GHz D7 : D0 CLKDIV CLK CH A CH B CH C CH D ZDOK 10Gsps ADC ANST7120-KMA Xilinx FPGA XC6VLX130T BRAM 10Gsps ADC Design Concept – Parallel Port Prototype at the coming August

One Baseline Correlator for AMiBA 2 Studying the possibility of low-z red shift. Stay at W band, only migrate analog correletor to digital correlator Deployment could be in the coming Autumn 2012 Original analog correlator ROACH digital correlator

4 Antenna Packetized Correlator Collaborate with CASPER

The Fast Fourier Transform Spectrometer CIDRE is a project of an heterodyne receiver embedded under a stratospheric balloon Its goal is to detect the OH and HD molecules with fundamental transitions near 2.5THz and 2.7THz The IF signal coming out from the mixer will be at 3GHz. The most challenging points about this FFTS are: -Its processing frequency (3GHz) -Its power consumption and its cooling At this altitude (40km), there is almost no air so it is very difficult to cool the FFTS. That is why we need to create a power efficient FFTS.

Packaged MMIC LNA MMIC mixer MMIC filter We are working on MMIC key components for many years… MMIC VCO PLL board

Feed Antenna Broadband dual-polarization planar antennas to eliminate the requirement of waveguide orthomode transducer, thus reduce the mechanical size. Low-loss MEMS switch would be used to switch between different bands. Slot antenna for two polarizations (Berkeley) + Horn (NRAO)

RF and IF Low-Noise Amplifier Experience on ALMA Band-1 development. T sys < 30-35K, T n for LNA should be < 15K Use low-noise GaAs or InP HEMT technology with cryogenic cooled down to 77K or 15K Cryogenically cooled IBM SiGe BiCMOS as alternative choice If un-cooled, we need 100x numbers of element to reach the same noise level.

Feedhorn SIW with planar probe (NRAO) LNA LO source and PLL or VCO as ADC clock signal 180˚ hybrid + filter (NTUEE) Mixer + IF amp. or ADC Antenna Integrated Rx Module Or Slot antenna for two polarizations (Berkeley)

Summary Possible items on SKA instrumentation are identified. For back-end, high speed ADC and new digital correlator are the core technologies. For front-end, MMIC-based devices might be the main contribution from ASIAA, mainly for SKA- mid and –high. Detailed evaluation on each development plan will be available later. Additional interested itemsAdditional interested items –SKA.TEL.SADT Signal and Data Transport –SKA.TEL.CSP Central Signal Processor