Wideband ADCs and FPGAs are changing the way RF Telescopes Process Data

RF telescopes using wideband ADCs and FPGAs

In the realm of scientific endeavors, determining when and how to upgrade a system for Radio Frequency (RF) telescopes can be a challenging task. Using RF telescopes one can determine with precision the speed and distance of a far off planet or explore the way in which our vast universe expands and more. Unfortunately, many of today’s legacy systems make it difficult to generate timely and efficient results.

RF telescopes and standard optical telescopes differ in that the RF telescope is specifically designed to amplify radio frequencies in the GHz domain rather than light waves. But, as the front-end of these telescopes are continuously being improved, back-end processing sometimes lack the full bandwidth needed to process large amounts of incoming data and therefore routine upgrades are required.

Today’s research scientists and astronomers alike are seeking to take full advantage of the latest advancements in technology. 

When a dated system for a 12-meter radio telescope needed an upgrade, Curtiss-Wright was called upon to provide hardware to enable a much more efficient and powerful spectrometer. The challenge, for one observatory, was to process a continuous 4-8 GHz IF input signal from an RF telescope, develop a digital spectrometer utilizing a 4 GHz wide Fast Fourier Transform (FFT) and to also minimize analog circuity for better reliability and noise immunity.

To solve this problem, an analog-to-digital (ADC) converter capable of supporting dual 12.5 Gsps inputs was required. Curtiss-Wright’s CHAMP-WB-A25G was selected for the task.

Wideband ADCs and FPGA Technology at Work

Why CHAMP-WB-A25G?

The CHAMP-WB-A25G in its unique design, couples the dense processing resources of a single large Xilinx Virtex-7 Field Programmable Gate Array (FPGA) with a high-bandwidth 25 Gsps 8-bit ADC module in a 6U OpenVPX form factor module. The 25G ADC module also has the ability to operate in a dual channel 12.5 Gsps mode, which was required. A FPGA module with the capacity to take in and process 25 GB/s of ADC data, along with a user-friendly FPGA toolkit that enabled integration of an 8192 point FFT core were also key factors.

CHAMP-WB-A25G Xilinx Virtex-7 6U OpenVPX Card Features:

  • OpenVPX (VITA 65)
  • Single user-programmable Xilinx Virtex-7 FPGAs X690T, with 8 GB DDR3L SDRAM
  • Single-channel 25 Gsps, dual-channel 12.5 Gsps 8-bit ADC
  • 20 x backplane SerDes capable of 10.3 Gbps each
  • Onboard PCIe Gen3 switch

CHAMP-WB-A25G key features

The size, weight and power (SWaP) optimized CHAMP-WB-A25G resulted in a smaller, but more efficient replacement than the customers’ existing spectrometer. With its ability to capture and process dual 4-8 GHz input signals, the A25G solution now provides the necessary enhanced capabilities needed for an esteemed 12-meter radio telescope. As a leader in FPGA technology, Curtiss-Wright’s trusted CHAMP-WB-A25G’s FPGA with its two 12.5 GHz ADCs and sample and hold device proved to be a perfect fit for the customers’ application saving time and money.